registering a new prop in bpy.types.VertexGroups I'm trying to make a panel for a addon i'm working on and one of the things i need is a checkbox for each vertex group of the active object. i have registered a boolean property for the VertexGroup type and am trying to use it as the bool value of the checkbox. no checkboxes have shown up and i am getting this error.

rna_uiItemR: property not found: VertexGroup.VisableBool

if i change to code so the new property is added to the Object type it works fine and shows the checkboxes but i need the bool props in VertexGroups not in Objects.

What am i doing wrong? i've been fighting with this for hours and can't seem to figure it out.

code snippet:

for i in context.active_object.vertex_groups:
        col1.label(text=str(i.name))
        col3.operator("mesh.dummy_op", icon="RESTRICT_VIEW_OFF", text="")
        col2.prop(i, "VisableBool")
        print(i)
        print(i.name)
        print(type(i))
def register():
        bpy.utils.register_class(DummyOp)
        bpy.utils.register_class(MainPanel)
        bpy.types.VertexGroup.VisableBool = bpy.props.BoolProperty(name = "Test", default = True)

Unfortunatly I have solved (not really) the problem myself. It turns out that the VertexGroup type is "Read Only" meaning you cannot add properties to it. The reason that it worked with the Object type is that it is not "Read Only". I guess i am going to have to come up with a new solution to the problem.


Creating dynamic, shaded backgrounds for animations I am still new to blender and am working on an animation of a light-responsive protein network in blender-python. I have been asked to create a shaded background whose color changes in accordance with the frequency of light shining on it. My question: how do I code a shaded background in python whose color I can change over the course of the animation:

Implementing the basic background using Blender's UI was straight forward: add blend-sky to the world and adjust its color's accordingly (Picture 1). Using the info tab, I attempted to recreate these commands in python:

 bpy.context.space_data.context = 'WORLD'
 bpy.context.scene.world.use_sky_blend = True
 self.world.horizon_color = (0, 0, 0)
 self.world.zenith_color = (1.0, 0.0, 1.0)

This however only results in "AttributeError: 'SpaceTextEditor' object as no attribute 'context'".

Next, I used a snippet of code from a previous answer I found on this very site (source: Creating cycles background light (world lighting) from Python), which produced a colored background but lacked the shading of the desired result (Picture 1).

 enter codbpy.data.scenes['Scene'].render.engine = 'CYCLES'
 world = bpy.data.worlds['World']
 world.use_nodes = True
 bg = world.node_tree.nodes['Background']
 bg.inputs[0].default_value[:3] = (0.5, .1, 0.6)
 bg.inputs[1].default_value = 1.0e here

Even if one of these two methods had worked, I would still be unsure how to program a change in background color. Can I create background animations using keyframes similar to object animation?  How do I even create the desired type of background in the first place?

Your help is much appreciated.

Pictures: http://imgur.com/a/IAA6G

Here's my solution. It provides for altering the Horizon Color and the Zenith Color, and assumes you are using the Blender Internal render engine.

It also allows you to provide a list of frame numbers and colour values for setting up multiple keyframes.

Also, the default interpolation type for animation curves is Bezier which would give you smooth transitions between colors. Because you want abrupt color changes I added code to alter the interpolation mode to Constant for the new animation curves.

import bpy

scn = bpy.context.scene
world = bpy.context.scene.world
world.use_sky_blend = True

#bgColorList[frameNumber, horizonColor, zenithColor)
bgColorList = [
[1,     (1.0, 1.0, 1.0),    (0.8, 0.8, 0.8)   ],
[15,    (0.8, 0.8, 0.8),    (0.8, 0.8, 0.8)   ],
[30,    (0.5, 0.5, 0.5),    (0.2, 0.2, 0.2)   ],
[45,    (0.8, 0.8, 0.8),    (0.8, 0.8, 0.8)   ],
[60,    (1.0, 1.0, 1.0),    (0.8, 0.8, 0.8)   ],
[75,    (0.5, 0.5, 0.5),    (0.2, 0.2, 0.2)   ]
]

#set up all keyframes for background colors
for bg in bgColorList:
    frame = bg[0]
    hColor = bg[1]
    zColor = bg[2]

    scn.frame_current = frame
    world.horizon_color = hColor
    world.zenith_color = zColor
    world.keyframe_insert("zenith_color")
    world.keyframe_insert("horizon_color")

#modify the interploation mode of the animationt curve to be consant for immediate changes on frame entry
for f in world.animation_data.action.fcurves:
    if f.data_path == "zenith_color" or f.data_path == "horizon_color":
        for kf in f.keyframe_points:
            kf.interpolation = 'CONSTANT'


Should I make my model into 1 whole or multiple parts? I have a human model.
It has 1 mesh for the body and legs. 2 for the feet, 2 for the hands, 1 for the hair and 1 for the head.
Should I make them into 1 model?
I want to use this in a game.

Whenever I rig, sometimes, say, the hand clips through the arm, or is completely detatched from it (Imagine it like a hand that's been only been sawed off about 75%, with a little piece of flesh keeping it attacked to the body. Twisted example, I know)

Also, if I want to make a background environment, should I make it all one whole, or multiple parts, such as say, one mesh for the ground, and multiple meshes for the trees?

I would say model all separate objects as separate meshes and group all objects that form a single continuous surface.

In the case of the human model it should probably be a single mesh object, since it is a "continuous single skin surface", that way you won't get discontinuities, artifacts or seams while rendering.

Edit: I am not into character modeling so my view here is bound to be inaccurate, as suggested below, a clothed character can optimally be subdivided into the several visible patches of skin, like say head, hands, legs, etc.

As for the background scene divide it sensibly as much as possible.
Take advantage of cloning and instances whenever possible for scene optimization. It can save a lot in file size, memory management while rendering and a lot of manual work updating different objects.
Terrain can be one single big mesh, each individual tree and vegetation should be single objects, etc.


Subdivide face with nice random effect I've stumbled upon a nice assets of low poly rocks and I'd like to create a similar effect. The transition between faces for these rocks are very smooth, I wonder if there is a tool/plugin I can use to create a similar effect (image attached).

This 3 modifiers produce similar effect:

We have remesh for create huge amount of square faces, next adding randomness by displace with noize texture, and decimate for creating big irregular faces. You can tune all settings to get different results.

Maybe, instead of creating geometry, try to use texture (as you suggest voronoi):

I use node group from here: Voronoi Cracks Fac?


Invisible Object Show Up In Final Render I am using Blender 2.79 I have an object that appears in the Cycles render that is not in the original scene. I have closed the file down and reloaded it. I checked everything in the outliner window looking for something. I am sure the object is a straggler as it was something I created before. I checked all the eye icons and they are all turned on. I tried to box select to see if I could snag the hidden item but nothing is selected.

If I use the render in the display viewports mode the invisible object does not show up. It only appears in the main render window. Any help with this would be appreciated. Thanks

I finally figured this problem out. I keep moving objects around then would render to see if the invisible object would move with it. After about a half hour of moving objects around I found the one object that was attached to the invisible object. It must have come in when I appended an object to the scene.  This invisible object was attached to many objects joined together. Which one is the culprit attached to the invisible one is beyond me.  It would be very time consuming to separate them all so just deleted. This fixed the problem.  But this still does not explain why the object came in invisible when it was appended into the scene.


Is there add-on to skip rendering for identical frames? I've googled a lot about it, but everyone suggests to skip them manually. It's not easy.

Maybe there is some add-on or script to make Blender render identical frames only once?
And then I can make the needed frames longer using video editors. It could save many hours of rendering.

Good news, everyone!

I found it! One Canadian guy created the add-on for this. It's called Dopplerender (lol).

Here is more info and link to download: http://creativityhacker.ca/2017/08/08/dopplerender-a-turbo-boost-for-blender-animation-rendering/


How to animate a mask with interval steps and not consecutive flow animation I'm animating a mask using the screw modifier and Boolean. but as the mask starts to reveal the LED lights, because its a consecutive flow animation, it's revealing bit by bit the LEDs, rather than one full LED at a time. How can I make the LEDs animate one at a time as the goes around revealing the LEDs.
https://streamable.com/1hwbei

At last, a use for the Build modifier?
Create a fan-filled circle-mask with the same number of segments as you have LEDs, rotate in Z to the desired start-point. Give it a Build modifier, set to the appropriate frame start/end, and 'Reverse'.

Segments are made visible one at a time.
@blender breath Thanks for the comment.. 'mask' is a bit vague - it could be so many things..

For a 3D mask, as you have done, assign a Solidify modifier to the circle, to get a cylinder disappearing in chunks, which can be used in a Boolean to cut away the LEDs
2D, a perfectly black Diffuse BSDF mask in a black world,
Or, as here, 2D, a Holdout mask through to transparent film, composited against a coloured background -

or, I'm sure, many other possibilities, for use in compositing, or as a texture.


Beveling a rounded corner until the beveled edges meet at a point I'm trying to continue beveling this rounded corner until it meets at a point without beveling too high on the z-axis.

If I use percent and set it to 100.00% it only works on the two long sides and not the corner. Could there be something wrong with my topology?

To bevel right to your edges you need to change the bevel tool from offset mode to percent mode and then set the value to 100%.


Can't get rid of shadow on mesh I'm a beginner and can't seem to understand nor get rid of this shadow over the mesh... I'm guessing it has something to do with the faces behind the plane (extruded from an edge). No modifier besides mirror, and smooth shading is enabled.

It's my first modeling attempt, so I may have done a lot of things wrong. Any suggestions?

What you are seeing aren't actually shadows. The dark area is caused due to an issue wit the normals of your mesh. The normals are the direction in which a face/edge/vertex is pointing, essentially which side is the outside and which side is the inside. The rest of your mesh is fine because blender can easily tell which section of the mesh is the inside and which is the outside. The reason for the dark area is because blender can't tell which section is facing out, since the front face is an exterior face, as well as the faces that are lying horizontal.

How you have the faces connected on the edge of where you have them highlighted isn't a good way to do it, since it can cause a lot of problems, one of them being the weird shading. You have a couple of options to fix it.

As Mr Zak pointed out above, you could just delete them since they likely won't be visible in a render.
Detach the outer edge of the selected area from the faces its connected to. TO do this, you will need to be in either vertex or edge select mode, and select the outer edge of what you currently have selected (not the middle ones where the mirror line is though). Then press V to rip the two edge loop apart.

I would think that the first option would be the way to go if you can get away with it.


Color Management panel in Blender I have some question about the Color Management panel in Blender

Display Device (Scene panel)

Now it seems to me that I have two options for Display Device in the Color Management Panel, either sRGB or None. I guess the color space for the monitor will be sRGB when I chose sRGB ? What happens when I chose none ? Will I see the linear color space ?

Exposure/Gamma
I guess under normal circumstances there are no reasons to correct exposure or Gamma ? When would this be useful ?

Render (Scene panel)

When choosing "Default" this means "Does no extra conversion besides the conversion for the display device.". That seems fine to me.

Sequencer (Scene panel)

The manual says:

  The color space that the sequencer operates in. By default the
  sequencer operates in sRGB space, but it can also be set to work in
  Linear space like the Compositing nodes, or another color space.
  Different color spaces will give different results for color
  correction, cross fades, and other operations.

Is this about rendering image sequences ? Or video editing ? I am not sure what is meant here.

The CM panel is somewhat confusing due to some unfortunate labelling.

  Now it seems to me that I have two options for Display Device in the
  Color Management Panel, either sRGB or None. I guess the color space
  for the monitor will be sRGB when I chose sRGB ?

Display Device is nothing more than a collection of View transforms. Think of it as a grouping.

  What happens when I chose none ? Will I see the linear color space

Close but not quite. You will see whatever the reference space sees. If you assign a different colour space to an image in the UV Viewer for example, you will see whatever you have set the image to, as transformed to reference. If you properly linearize a display referred sRGB to display linear via a correct transform, you would see those values dumped directly to display. In the case of a typical LCD panel however, we have to remember that such electronic displays, though they operate almost strictly linearly, will have a 2.2 power curve baked into their lower level hardware. So the not-so-simple answer is that you would be seeing display linear values dumped to a 2.2 power curve in all likelihood.

  I guess under normal circumstances there are no reasons to correct
  exposure or Gamma ? When would this be useful ?

One could correct exposure via the exposure control, however in most typical situations, the two controls are used to check compositing. Bending values can reveal problematic keys, comps, and other details, as well as previewing looks / creative grades, and how materials respond.

  When choosing "Default" this means "Does no extra conversion besides
  the conversion for the display device.". That seems fine to me.

Default is simply a label. It is the sRGB specification's transfer curve. While default, the sRGB transfer curve was never intended for rendering, and has many implications. See some of my other answers on wide dynamic range for further information.

  Is this about rendering image sequences ? Or video editing ? I am not
  sure what is meant here.

This is a byproduct of the VSE being hacked around how OpenColorIO was designed to work. It is how the VSE sees image data in its reference. That is, it is a hack around how OCIO was designed to give the VSE a unique reference space.


Get the active/current clip in Motion Tracking tab I'm trying to get/set tracking values of the currenct active clip in the motion tracking tab, but I'm having some problems.
Is there a way to get the currently loaded clip without knowing the name? I thought that using context.active_clip would work, but that returns None.
Currently I need to loop over all clips with:
for clip in bpy.data.movieclips:
    for o in clip.tracking.objects:
        print(o)

It seems bpy.context.edit_movieclip is doing that I was looking for.


Saving intermediate stages during rendering I am using cycles and progressive rendering.
What I need to do is save all the images coming from intermediate stages.
For example, I set the sample number to 500 and what I need to get is having 500 images with more and more samples used. Is it possible?
I am new to blender. Sorry if I am asking for a very simple thing.

Best,
Krzysztof

Unfortunately, it's not possible to automatically save multiple stages of the progressive render. The nearest you can get to this is to render multiple images with a small number of samples and then combine them to produce a result - similar to the progressive render.

To achieve this you need each 'frame' to be rendered with different 'seed' setting. The 'seed' is the source of the 'noise' in the render. Different seeds produce different noise and when these are combined it results in the noise effectively cancelling out. The seed for the render is available in the Sampling render properties. Alongside the Seed value is a clock icon - clicking this will use the frame number as the seed and this will result in a different seed being used per frame.

As an example, here are multiple frames rendered with 1 sample each, each with a different seed :

Combining multiple images is most easily achieved using tools outside Blender - such as ImageMagick. To combine multiple images using ImageMagick you can use the following command line :

magick convert *png -average result.png

This produces the following result :

To produce the 'progressive' result (multiple images at different stages) you would simply combine fewer images for each 'earlier' stage in the process (for example, images 1-20, images 1-40, images 1-60, etc. for progressively more detail).

Note, however, that better results will be produced from the 'actual' progressive render due to losses resulting in each individual frame - for example, values outside the 0.0 to 1.0 normal range are not stored in individual PNG renders. This will result in the loss of some details such as caustics.


How can I disable auto ease in So we all know its there, and we all know how to fix it, but adding the extra steps to have to change the interpolation on every new animation just plain sucks. To be honest I don't find this feature useful as a default at all because more times than not we have to correct for it.

Is there an option somewhere to turn auto ease in off? (I personally think this should be the default and should require user to turn it on if they want it).

It is a matter of opinions,... most movement in animation and in real life starts from zero, then reaches a certain speed, then decelerates and stops gradually, constant linear motion can feel robotic.

In the user preferences you can set the default interpolation for New F-curves
to one that suits your needs:


Bend extruded svg around sphere or extrude svg along sphere normals I am trying to cut out the rebel alliance symbol from a hollow half sphere the size of a golfball to 3D print a golf ball marking stencil. I tried this with tinkercad and already printed it successfully like this:

As you can see, I simply extruded an svg and cut out straight down. This works somehow, but of course it is a straight cut, which especially on the outer curve produces quite an angled border compared to the normal of the golf ball, which makes painting the edges harder than it could be.
Now I wanted to bend the symbol along the normals of the sphere curvature using blender and a technique I found here: https://blender.stackexchange.com/a/115121/116795 , bind object with SurfaceDeform modifier to plane, bind Plane with shrinkwrap to Sphere. And it worked, but it somehow looks ragged especially on the inner curvature:

I have played around with the modifier settings like an offset for the shrinkwrap, increasing subdivision, even using the Remesh Modifier to get a different distribution of vertices along the edges. But nothing was really clean.
Basically what I would really want is to extrude an arbitrary svg along the normals of a sphere - in my imagination this should deliver the cleanest result.
So any tips to improve the quality of the edge curvature or pointers to a completely different technique would be highly appreciated, thank you!

I tried the suggested Solidify on a single-skin sphere, but I didn't manage to get the result I wanted. But I worked out a similar approach - with a little more work and without modifiers, that did the trick:

Create Sphere of approriate size
Use Boolean to cut off lower half to get to the desired half sphere and cut out the desired SVG symbol as I did before
Use "Edit Mode" to remove all inner vertices created by the booleans to produce a single skin sphere with cutout as suggested by Robin.

Duplicate the object, scale it so there is a second, slightly larger version of it - as desired for the thickness
Join the two objects and "stitch" the edges with CTRL-E - "Bridge Edge loops"

I had to select the inner cutouts manually, "select loop" didn't work there. But in the end, the result was worth the effort:

Thanks for your help, I hope somebody finds this useful!
UPDATE: I also found out why the solidify didn't work before, I didn't actually use a singleskin sphere (Step 3 from above), but instead I used a boolean operation to cut out the inner side with an only slightly smaller sphere. Which LOOKED single, but actually was a normal doubleskinned sphere. With the singleskinned sphere, it worked like a charm. So, thanks again Robin for the suggestion, you were spot on, if only I had done it right in the first place, this would have worked perfectly!
So, alternative to my more time-intensive method:

Create Sphere of approriate size
Use Boolean to cut off lower half to get to the desired half sphere and cut out the desired SVG symbol as I did before
Use "Edit Mode" to remove all inner vertices created by the booleans to produce a single skin sphere with cutout as suggested by Robin.
Switch back to "Object Mode" and use the Solidify modifier to get the desired effect with a lot less effort :).

Update 2: Yep, it works :)


Is there a way to navigate the file system more efficiently in Blender? I feel like I waste a lot of time clicking around trying to find files in Blender's file navigation system. Is there any way to use the python shell or some plugin for navigating the file system more easily? The "Recent" folders is helpful, but not quite fast enough...

If you know the path you want, You can copy and paste it into the address bar. That'll take you straight to where you want to go!

For me, I keep all of my related files local to the blender file, as if the blender file is a main project.


Paint on UV'ed model with external editor The thing is that the guide I'm following uses 3Dcoat to have the texture projected from the one side to the other side. I figured that Blender would be able to do this also, but I'm not quite sure how it works. I've tried to search the internet and there's probably guide, but I do really not know what to search for to find what I'm looking for.

Guide that I'm following: https://www.youtube.com/watch?v=FiNASmArkxA

EDIT

Thanks for the help, I found what I was looking for. https://www.youtube.com/watch?v=hb-OZTNFatw

UV unwap the object, enter edit mode, go to the UV editor, click UVs at the bottom and finally click Export UV layout. It will give you an image with a UV template image, which you can paint over and then load back into blender.

Update: Based on your comment, try cutting the object in half using K and deleted one half. Then use the mirror modifier to restore the other side. Then position the viewport in the position you would like the final 2D texture coordinates to be. Now go into edit mode, press U and then unwrap from view. Follow the remainder of my steps from there.


Looping through selected objects one at a time? OK, from the selected objects, I need to join one selected object with the active object and execute some other code. Then from the others select the next selected object and then execute the code again. I thought the following would work ,but it does all at the same.

import bpy

SEL_OBJS = bpy.context.selected_objects
ACT_OBJ = bpy.context.active_object

#Join one at a time and execute more code
for OBJS in SEL_OBJS:
    bpy.ops.object.join()
    #More code here

Got my code working with the following.

import bpy

SEL_OBJS = bpy.context.selected_objects
ACT_OBJ = bpy.context.active_object

#List of all objects but the active object
SEL_NO_ACT = [o for o in SEL_OBJS if ACT_OBJ != o]

#Deselect list objects
for OBJS in SEL_NO_ACT:
    OBJS.select_set(state=False)

#Loop list objects
while len(SEL_NO_ACT) >= 1:
    OBJS = SEL_NO_ACT.pop()
    OBJS.select_set(state=True)
    bpy.ops.object.join()
    #Run code for each object after joining

Essentially you need to create a list of objects based on the current selection that will not change if the selection changes.

import bpy
# store selection in list that in future will not change with selection
sel_objs = [obj for obj in bpy.context.selected_objects if obj.type == 'MESH']
bpy.ops.object.select_all(action='DESELECT')
if sel_objs:
    obj1 = sel_objs.pop()
    obj1.select = True
    bpy.context.scene.objects.active = obj1
while len(sel_objs) >= 1:
    obj2 = sel_objs.pop()
    obj2.select = True
    bpy.ops.object.join()


Physical iridescence in Cycles? Having recently seen the Siggraph paper A Practical Extension to Microfacet Theory for the Modeling of Varying Iridescence, I of course said to myself "I have to have this in Blenderrrrr!" and started to experiment with a node setup to at least simulate it.

The paper, while not too long, is quite technical and mathy, and over my head. But I did glean some basic information from it (please point out any mistakes):

Iridescence is the result of a phase shift during refraction.

The colors of iridescence can be represented by drawing a spiral curve through a color space.

The color banding changes with the incident angle. So, of course the good ol' Fresnel effect is at play here. Seems logical to assume we need to have physically accurate Fresnel if we want to have physically accurate iridescence.

It seems all this complex math can be represented in approximation by a color ramp! Heyyyy, I use color ramps all the time. Maybe this won't be so hard after all.

I don't know what $\mathcal{D}_\text{inc}$ is though... (no dinc jokes in the comments, please). If you know what it means, please comment or answer.

Could this approximation be perhaps close enough for our practical rendering purposes?

Let's take our screen shot of the gradient and crop it:

Instead of painstakingly setting hundreds of gradient stops for the color bands we can plug in the cropped image of the gradient with the vector data from a Layer Weight node like this:

Now we have fake iridescent color!

From here I've been experimenting with PBR node setups and trying to plug this gradient color data in in some meaningful way. I've made some neat looking materials, but as far as physical accuracy goes, I can't say I've made much progress. Since my understanding of the paper is incomplete, I'm asking the community: Can we create an iridescence shader like the one described in this paper, in Cycles?

"You DO have this in Blenderrrrr!" since POV-Ray does support Newton's thin-film coating under the iridescence keyword:


Delete output image file on error I am currently supervising a render farm which is working using the simple "create empty file when starting a frame" and "don't overwrite existing files" on a shared network file system approach. Unfortunately, one of the computers bugged out a few days ago (without me noticing) with a Cuda error and kept rendering hundreds of black images.
The problem is that these black images prevent other computers from taking over where that one computer failed.
The other PCs stopped as they thought there's nothing to do anymore.

Is it possible to set Blender to not create a black image if there is an error, but instead delete the placeholder file?

With a lot of trying and testing I came up with the following solution, which is a bit of a hack but it works so far.

I did not find any direct way to find out if there was an error in the rendered image. So I am resorting to analyzing the rendered image after it has been generated.

def PostRender(scene):
    print("Post render: Frame {} of scene {}.".format(scene.frame_current, scene.name))
    if scene != bpy.context.scene:
        # this is not the main scene. skip
        return

    file_invalid = 1
    try:
        print("Retrieving last output file [{0}]".format(last_output_file))
        image_object = bpy.data.images.load(last_output_file)

        num_pixels = len(image_object.pixels)
        width = image_object.size[0]
        height = image_object.size[1]

        # in every 10x10 pixel rectangle, test one pixel. this makes total 1% of the pixels spread all over the image
        for x in range(0, width-1, 10):
            for y in range(0, height-1, 10):
                xoff = int(random.uniform(0, 9))
                yoff = int(random.uniform(0, 9))
                pix_at = 4*(x+xoff + (y+yoff)*width)
                for i2 in range(3):
                    if image_object.pixels[pix_at+i2] != 0.0:
                        file_invalid = 0
                        break

    except Exception:
        # error accessing data. file is assumed to be invalid
        pass

    if file_invalid == 1:
        print("Image seems to be invalid.")
        # handle the error case here

bpy.app.handlers.render_post.append(PostRender)

By checking only 1% of the pixels, the loop is very fast even for huge images. If you want to be one hundred percent sure, you can add a second loop afterwards for scanning all the pixels if file_invalid is still 1.

This approach has the obvious shortcoming that it will not work if you have black images in your animation.

Possible options what to do to handle the error:

Leave a log file entry
Optionally delete the file
If you suspect a CUDA error (as in my case) it might be a good idea to reboot the computer
Restart rendering after reboot

I found the last two points especially interesting and implementing that has increased the productivity drastically, since I don't have much downtime anymore. I will not post the implementation here, since it is out of the scope of the question.


Material and Textures looks Completely different in Unity I'm modelling a Curved Gate/Door in Blender, rverything looks fine in Blender, but in Unity, it looks dull and stretched.
I even tried to tweak the material's settings (tiling is uniform 1, 1) but I couldn't get the desired result.
Here are some pics:
https://ibb.co/F3fZ8GG
https://ibb.co/kx9VCTJ
https://ibb.co/ThjyG6K

I think it might be the reason that josh sanfelici mentioned.
Also check this https://forum.unity.com/threads/can-blender-2-8-eevee-shaders-still-be-used-with-unity.645271/, that someone mentioned about using HDPR. I am also looking for the answer.


Transparency animation not working with a plane I'm trying to create a simple animation. I have have a plane and a line, first the line fades out, then the plane fades out. For that I am using the transparency value. The line fades out just fine, but I am having problems with the plane. I set a key frame with the transparency value at 0 in the frame 260:

And then I set another key frame at the frame 320, with the transparency value at 1.

But the plane is still there, still visible, I do the same with the line and it works fine. What am I doing wrong.

I found out the problem. I had to change the setting in the render properties, light paths, to allow more transparency.


Adjacent faces are separated on the UV map I have a truncated cone, open on both sides, laced near the top, with rims/curves along the top and bottom edges:

However, whenever I unwrap the object using the cylinder method (which seems to give the best layout solution overall), several faces that are adjacent on the model appear on the other side from their counterparts on the UV map:

This happened to the faces near the marked seam, but removing the seam - having no seams at all - results in the exact same layout.
The model does not have any modifier.
Does anyone know why this happens and how I can prevent it, or change this behaviour during unwrapping?

Additional images of the model (click for larger versions):

There's a problem in your model's topology.  Do this experiment.  In the UV editor, after you've done the cylinder projection, deselect everything and then carefully select the top row of vertices:

Since you've enabled UV Sync Selection, the same row of vertices shows up in the 3D view:

But if you zoom in to the active vertex you can see an issue:

It might be easier to see in edge select mode:

the path jumps from one edge loop to the other.  I don't know how to solve this directly, but my horrible work around is this:
select one of the vertical edge loops:

delete everything else:

add a screw modifier with the same number of steps:

and apply the screw modifier, in object mode.  The result is:

Notice that I didn't mark a seam, because I didn't know where you'd want it.
I don't honestly know what the topology issue is, but this "fixes" it.


Creating a procedural stone texture I am trying to create a really worn-out stone texture. Here are some images similar to what I'm looking for:

I'm looking for something that looks like the first image. Dirty and greyish-black. But I want it cracked like the second image. What kind of procedural texture nodes can/should I use for this? Here's what I got so far:

I have made a node setup that renders like this:

It consists of two diffuse shaders. One is your stone texture from above (well almost). The other is a simple green "dirt" material. The real trick is to combine the dirt with the stone in a believable pattern. I tried multiplying two noise textures with some distortion. Distortion makes noise be liked two colors of paint where you have stirred it some. You get a swirling pattern.

To get this further, I would add some bump to the dirt shader. Also, I would bake an AO map and use that in the mask, letting it influence the mask so that there is more dirt in crevices.

Here is the node setup.


Where is the Symmetrize option under Remesh is located now? where is the "symmetrize" option that used to be under "Dyntopo" > "Remesh" now? I'm using 2.9, and I couldn't find it

Just expand the ► Symmetry section (next section in your screenshot), at the bottom there is the Symmetrize button. (Blender 2.91)


Smoke being generated blocky I was trying to render this two smokes being generated by following particles along a path determined by a force, I already applied all transforms for both domain and emitters and it still renders like this.
The last thing I tried, before posting, was to change density in hopes it was going to become more soft but it stills renders like its.
The smoke is emitted from a cube and I dont know if this changed anything but right know I just truly dont know how to fix this blocky look.

Also, here is the blend file, I cleared the scene and just left the particles there.

I also have this problem regularly and i figured out this is because of low Resolution , you need to increase Resolution Divisions of your domain to something like 400 or 500 for good results but WARNING if you are working on a low spec device like a normal consumer laptop , Even with 4 gb or 8bg ram this could be problematic but if you have a good build with some OKAY graphics , 500 divisions should not be a problem but on a simple laptop Blender will HANG as hell of you even crank up to 200


2.8. background image doesn't show up in final render I added a background image with ADD>IMAGE>BACKGROUND
The image appears in viewport but when I hit F12 to render, it does not show up. What did I do wrong?

The Reference and Background images actually insert viewport-only Empties, with images referenced on them. This feature is primarily for displaying blueprints or plans, reference items used during modelling, not intended for final render.

What you're looking for is to add an actual mesh plane into your scene, and texture map it with an image. That's such a common operation, there is a built in script to do it. I do not know why it isn't enabled by default when you install Blender.
To enable it:

Go into Edit > Preferences, then Addons on the left-hand column.
In the search field type 'images'. You'll see "Import-Export: Import Images as Planes" appear.
Enable the checkbox next to the addon's name.
Close the Preferences window.

A new third image option will now appear: Add > Image > Images as Planes.

This script opens one or multiple images at once, properly adds and proportions a plane for each, and adds correct texture, material and UV settings. That's what you'd need to do, end-to-end, to have a "real" image in the scene that shows up during render.


Is there a way to lock edge lengths of a mesh in edit mode? I want to edit a mesh without distorting it, so that only the angles between the edges change but not the length of the edges.

I basically need this to model realistic clothing where I model the 2d shape (that one would also cut out of real fabric) and then "sew" it together manually.

I already tried doing that by actually using sewing with a cloth simulation but that is not very efficient and does not leave a lot of freedom.

It sounds like using a curve modifier might be the most practical and fastest solution. This might distort the shape of the thread (if it is a mesh) slightly but should (as far as i know) preserve length.

But if it has to be in edit mode you could alternatively use the rotation tool when the rotation center is set at "active". Then, for example, if you select half of the string and the middle vertex is active you can change the angle between both halves of the string without changing any lengths.

Happy Blending! :)


Texture disappear on joining I am making a tree, in which I have a texture for the central tree object or bark, and branches have a different texture.

I applied the branches on tree with particle system.  Till then the textures were fine.

Then I convert the particle system and delete the particle system.

Then ctrl+j join to the main bark texture with the branches, with the bark or central stem as parent.

Doing this, texture from my branch material disappears.

Please anyone help me out.  ASAP.! Thanks

Be sure that both UV Maps have the same name, otherwise the textures will not share the same space when they are a single object.


Changing a material's name with Python I can do a LOT of things with Python in Blender, but for some reason I'm struggling with changing the material name.

When I import an FBX Blender renames the material names if they are dupes.  So I get a "Glass.001", "Glass.002" but I really need them to all just be "Glass".  I can rename them manually with no problems, but my code to do so fails.

for obj in bpy.data.objects:
    for num, m in list(enumerate(obj.material_slots)): #rename materials with . numbers
        if m.material:
            myhold = m.material.name
            if myhold.find(".") > -1:
                print ("Material is", m.material.name)
                tempholder = myhold[:myhold.find(".")]
                m.material.name = tempholder
                print ("Material is now", tempholder)
                print ("So should be", m.material.name)

which prints something like:

"Material is Glass.001"
"Material is now Glass"
"So should be Glass.001"

It must be something obvious but I don't get it.  TIA for any help.

Each material has a unique name

Each ID object in blender has a unique name. Internally blender does this for us if needed. Eg duplicate the cube. This is often referred to as the "naming system".

For example, If another material already has the name you are trying to assign, to test bpy.materials.get("Glass") is not None then cannot name another material "Glass". Can try to, `anothermaterial.name = "Glass", but the naming system will rename it with a .nnn extension.

This explains the behaviour described in your question.

  I can rename them manually with no problems

Seriously doubt that claim. Contend that instead you are also unwittingly renaming the original. (or selecting it from material drop down)

Rename green material to "Material" just like blue

If you want to link to only one;  assign the material to the "Glass" original, eg using the tempholder name from script above

m.material = bpy.data.materials.get(tempholder)

Assigning each slot linked to  "Material.nnn" to "Material"

Prevent Blender to add numbers behind materials when importing a FBX

Disable Material Duplication


Where are the other AO settings in blender internal? Where can I find the extended AO settings just like in the viewport one?

Most of those have similar properties in the gather panel in your screenshot for the Blender Internal ambient occlusion:

Samples - in gather panel
Distance (attenuation distance in BI) - in gather panel
Strength - Factor in AO panel
Attenuation - Falloff Strength ("Falloff" must be enabled)

Note: You will probably want to change the AO to multiply instead of add to further mimic these settings. It is also important to mention that these are two different AO systems and don't have the same functionality.


Shading issues after normals baking a). I baked normal map and applyed it to lowpoly mesh and I made 3 clones of it with different options for demonstration purposes
b). I got the issue with shading
What I want to be: lowpoly mesh without additional geometry and with correct shading and smooth
At the screenshot you can see (from right to left):
1.highpoly mesh that I baked from
2.smoothed lowpoly mesh with additional geometry I want to reduce, but it has correct shading and smoothing
3, 4 and the second screenshot. lowpoly meshes that I want to produce, but with correct shading and smoothing
So how can I do this?

blend_file

To fix to shading in Blender, select the 2nd object in Object mode ...

go to Object Data Properties tab

expand ► Normals, and activate ☑ Auto Smooth, 30°
expand ► Geometry Data, and clear the x Custom Split Normals Data

go to Modifiers tab

remove the WeightedNormals modifier


How to display names of objects in viewport Is there anyway to display the names of objects in a scene, all at once like the option we have for bones? Yes,we can do it individually..but if there are many objects its better to have have common control
I am working with a mechanical assembly,its very difficult to keep track of objects.
Any hidden option or  add-on information would be helpful.

Thanks.

Select all objects by hiting A. Then in the
Properties areas Object tabs Display
group check the checkbox Name for name display.
Then right click the checkbox and select the option
Copy To Selected. Works on almost all options.

Edit: In current versions, using alt-click on
properties applies them for every selected object.


Align loopcuts (so it looks like one big face) i have a problem that loopcuts are throwing shadows when i render. I basicly want an area to look like it was one face instead of multiple. Her is an exeample what i mean:
This is my model:

and this is it rendered. The red circles show what i mean.
It's more pronnouned when i look from other angles.

The lines in the first red circle i could life with, but the lines in the 2nd look really ugly from other viewpoints. If i delete all the faces and make one big ngon face from it it looks nice, but i of couse want to avoid ngons.
So how can i fix/align this, so that it looks like it was one face?

A series of narrow/thin faces like this will easily lead to such problem if the "big face" isn't as flat as they were coplanar. So the main problem here is about topology actually.

Try following steps to solve this issue:

Select all narraow/thin faces that form the "big face", then press F (or X > Dissolve Faces) to make it as a big Ngon face;
Press Spacebar and search for Split Non-Planar Faces (or access from Mesh > Clean up > Split Non-Planar Faces); F6 to adjust the max split angle until you get the expected result. (In your particular case, setting to 0° will triangulate it too, which means you can ignore step 3 below);
CtrlT to split Ngon faces into triangles. (optional)

Tip: For Step 2, You can also split it manually instead. Two nice ways are:

Press K to enable Knife tool, then cut line(s) on the big face;
Select two vertices, then J to connect them by adding a new edge on that face.

Either way above can help when doing retopology.

If you really don't want to change the topology too much, then a quick and dirty way at least would be:


Little problem with arm movement in my character's walk cycle It's obvious not right when both arms move backward. There are some little 'Khực khực' there. Oh sorry I could only describe that in my language LOL.
   Anyways, that's like some robotic displacement causing false action (false movement?). Oh just take a look in the blend. file here LOL

Your arm IK control bones (Arm.L and Arm.R) are positioned too far in parts of animation, so the arms need to extend too much and are no longer bent in elbow. That causes the elbow popping in the walk cycle.

Also the same bones are not looped, so that causes another discontinuity when looping the animation.

Keyframe these bones more carefully to not overextend the arms and loop them and the animation will be fine.


A restricted view I can't turn off in Solid & Wireframe preview For some reason I keep getting this strange restricted view only in solid & wireframe viewport mode. Doesn't appear in render preview. See the attached pics to see what I mean. Can anyone tell me what this is and how to remove it please. In solid preview:
And in render preview:

It looks like you've enabled a Clipping Region. Select it again from the menu or use shortcut ALT + B to clear it:


How to create a horizontal strip inside a circlular plane? I need to create a horizontal strip from one side of the circular plane to another circular plane inside it.
The result needs to be like this:

I got the outer circles using the inset key like this:

I got this now only an intersecting rectanglular face is to be added but i dont know how to.

It really depends on your final goal but you could do it with the help of the knife tool (K then C to cut orthogonally). Also, use a Mirror modifier to make it simpler:


Why the water hasn't the right strenght to reach and to fall at the end of the road? I'm playing with the fluid simulation and I want to reach this result. Instead,this is the result that I get. In short words,the water hasn't the right strenght to reach and to fall at the end of the road but it falls on the way. What's wrong ? thanks.

blender file

There are couple of issues with your file.

Your pipe obstacle has wrong normals. The solidify modifier is applied only after the fluid simulation (see the order of modifiers), so the simulation is done using only the inner shell with flipped normals. Remove the fluid obstacle modifier, apply the solidify (check normals) and add the obstacle again.
Your inflow is highly suboptimal. Not only is it inside of the pipe, I would recommend an inflow plane altogether (if so, switch to shell)

The inflow has very weird inflow velocities They should point in negative y direction (and from some tests, they should have much smaller values).


weight painting in blender displaying black color While weight painting the mesh only shows two colors Red and black in solid mode. It is not showing intermediate values like green and blue. if I switch to wireframe mode the weight colors are displaying correctly. How to rectify this? I am using blender ver 2.83

Perhaps the shading of the viewport is shaded to the maximum. Reduce from 1.0 to .25. If you want you can also set Lighting for FLAT.
Hope this helps.


Why can't I find my render? I can't find my render anywhere. Now matter what folder I choose, when I go to that folder I don't find my render. And the only option left is to screenshot and crop or something. Please help. Blender version: 2.79

Blender sticks rendered images in /tmp on Mac and probably Linux. (I don't know about Windows.) It'll be called something like 0003.png.

You can save your rendered image somewhere by pressing F3 (Fn+F3 on a laptop) instead of trying to dig for it. This also lets you conveniently name it.


Cutting bevel in mesh surface In the picture I've selected the edge loop I would like to see "cut out" like a bevel, so like a kind of groove in the cube's surface. The Bevel Modifier only seems to work on edges that are at the cube's actual edges. I tried assigning the loop edge to a vertex group, and then select "vertex group" in the bevel modifier, but to no avail. Please advise

Do 3 loop cuts (Ctrl+R) really close to eachother. Then select the one in the middle (Alt+Right Click) and scale it down (S).

Another option would be to separate the mesh by the selected loop. I don't remember if you can do that, but you can always select half the cube and make it a new object (P), then join it back again (Ctrl+J).

Excuse my poor answer but I don't have Blender on this computer to give you some pictures.


Array Modifier with Offset Object Issue I'm going through Roland Hess' Blender Foundations book and I am having issues with the array modifier (using offset object).

I am trying to make feet for a table, my issue is that rotating the offset object (an empty named "empty" in the file) does nothing.

All I can see is the single object with the array copied right in the same position.

The blend is here, help is greatly appreciated!!

You need to disable "Manipulate Center Points" to be able to rotate the object the way that you are thinking:

Funniest thing is, I went through that same book years ago and had the same problem while making that table :-)


Attach swords to mesh/skeleton for exporting as FBX Is it possible to join a separate sword like the one in the picture to a preexisting humanoid mesh. Then have that sword be linked to the wrist bone with a bone in the handle and have the sword be controllable on its own, even though its apart of the humanoid mesh and armature?

Im desperate for an answer on this. Any sort of input would be greatly appreciated.

If you want the swords as part of the character mesh, you want to add sword bones that are children of each hand and use them to control the swords.

In the armature, add a bone for each sword, let's call them sword_l and sword_r. Position them where the sword handles are and have them as children of the hand bones. As children they will follow the hand bone but can be moved separately when desired.
For each sword, remove the child of constraint, and create a vertex group matching the bone name, sword_l for swordL and sword_r for swordR. In edit mode select all vertices and assign them a weight of 1.0 to the vertex group. This will make the entire sword move with the bone.

In object mode select both swords and the character and press ⎈ CtrlJ to join them into one mesh. The vertex groups from the swords will also be part of the combined mesh and each sword will now move with the sword bone. As the sword bones are a child of each hand bone, they will follow the hand movements unless you keyframe their location away from the hand.

This is your model with both sword bones.


Light trough the object on render I have lamp model and point light inside of it. You can see lights on preview, but i can't see the lights on render. How to make them glow correctly?

There are numerous possibilities as to what causes this. I tried to list them in order of likelihood

your material for the lamp's glass material does not look transparent (you can set it to translucent, but be ready for some serious noise)
your lamp is too weak for cycles
your lamp's cycles visibility options don't make it show up where it's supposed to illuminate.

There's more, but please make sure the ones above don't apply and if not send another screenshot with the lamp selected, meaning showing its settings as well as its place in the outliner.


Freestyle multi-color per object? New Blender user--
Can you mark edges for a single object to different linesets in order to assign different colors (in line style)?
Many thanks

I'm adding this drawing-- solid geometric object with selected edges marked for freestyle render-- but in different colors, thickness etc.
(Sorry i didn't do this originally, and just saw response after Thanksgiving travel.)

I would suggest using the Material modifier for the freestyle edges.

Apply different materials to the object for the parts you want to color.

To control a property, use the Material modifier and select the material property.

Select the Freestyle Line color as you wish. I'll use the Diffuse Red channel to control the thickness and the Diffuse Blue channel to control the Opacity.

Note that the color channels can have any float value.

The green material has a Priority of 1.


How to make a material change based on the light it recieves? I want to make something that has a black glossy shader when a light hits it, e.g. the sun, but when no light hits it at all it turns into an emission shader. I can't figure out how to actually do this, I've tried using the Light Ray inputs but it didn't work.

I am sure Rich Sedman can figure out a mathematical way with nodes.

However I think I would just use drivers for this.

For your material have your glossy shader mixed in with an emission shader.

Right click on the fac of the mix node and choose single driver "set up later"

Make sure you have auto run python in the user pref.

In the graph editor make sure you have it set up like I did. You will need to set up your variable and name it correctly. Choose the spot light and rotation as the object to link the driver to.

When you move the spot light it changes the fac amount on your mix node.


How to change the speed of an action in bge without interrupting the loop? I have an analog controller and I want to change action speed on the runtime, but without interrupting the loop of the action. I tried this but it doesn't work. The loop restart all the time when the variable_that_changes changes.

armature_object.playAction("run",0,30,play_mode = bge.logic.KX_ACTION_MODE_LOOP, speed= variable_that_changes)

I suggest to use skip the automatic play modes and implement an on counter.

You can do this even without python. Define a float property "frame" that is supposed to hold the frame of the pose to be played.

Whenever the property change activate an action actuator in property mode with that property.

Now you can implement logic that manipulates the property frame.


How to make Blender remember STL export settings as default I model in millimeters inside Blender, for 3D printing.
Every time I want to Export STL, I have to untick Scene Units and change the Scale to 10.0. These settings aren't remembered.

How do I save them as defaults?

Solution

Manually

To remember unit settings make your adjustments then File > Save Startup File (Ctrl-U)
To change STL Export defaults navigate to
C:\Program Files\Blender Foundation\Blender\2.74\scripts\addons\io_mesh_stl
and open the __init__.py file.

global_scale is at __init__.py#L166, change default=1.0 to 10.0

use_scene_unit is below at __init__.py#L172, change default=True to False

Windows PowerShell Script

Configure Blender STL Export default settings - GitHub Gist


Delete multiple keyframes at a time? How do you delete multiple keyframes at a time? Pressing space and having to click buttons seems inefficient.

In the graph editor or dope sheet select all of the keyframes you want to delete and then you can delete all selected items at once.


Can we modify the code of blender and use it as a analysis software? Can we modify the code for blender, create our own addons and use it as the analysis softwares like catia, ansys eyc.,

What do you mean "Can we"?

"Can we"  as in are we able to legally do it, or "Can we"  as in is it technically feasible?

Either way the answer is probably yes to both.

Blender is Open Source software so you are mostly free to modify it as you see fit, as long as you publish it under a compatible Open Source license if you make it publicly available.

Quoting the license:

  Blender is released under the GNU General Public License (GPL, or
  “free software”).

  This license grants people a number of freedoms:

  You are free to use Blender, for any purpose
  You are free to distribute Blender
  You can study how Blender works and change it
  You can distribute changed versions of Blender

  The GPL strictly aims at protecting these freedoms, requiring everyone
  to share their modifications when they also share the software in
  public. That aspect is commonly referred to as Copyleft.

Technically speaking, I have no clue but Blender codebase is very adaptable, you could probably do it too if you are willing to roll up your sleeves and put some elbow grease in.

Whether it will be easy or hard is another matter, the source code may require substancial changes to support that kind of features, to the point of no longer being worth it to build on top of Blender.

That being said Blender as proved to be very flexible and versatile, and it has been adapted for many different workflows and industries, so it could probably be adapted for that too.


dupliframe alternative for 2.8 I'm trying to create this image in Blender:

My first thought was:

rotscale animation
adjust the curves in the graph editor (the rotation step is smaller at the outside vs )
dupliframe

I see dupliframe got dropped in 2.8 though. Is there an alternative that would work in Blender 2.8?

I've been trying to achieve it with an array modifier using object offset for rotation and scale. This doesn't work though because of the need to vary the rotation step

I've also been trying to adapt this answer, but so far unsuccessful.

From this base figure:

We can place a Bezier curve:

And add a screw modifier to it (360 degrees with 3 steps):

And add an empty as pivot point for the modifier, then move it up until triangles are aligned:

You can play with the curve resolution to vary the amount of triangles.

To render it after that (did not pay attention to the edit mode above):

Convert the result to a mesh and add a wireframe modifier with a low thickness:


Can I save rendered images as PNG with a sRGB color profile? It is my understanding that I can save rendered images at best as PNG files. But what about color profiles ?

The manual says:

  The other place to keep color management in mind is when loading and
  saving image files. File formats such as PNG or JPEG will typically
  store colors in a color space ready for display, not in a linear
  space.

  When working with image files, the default color space is usually the
  right one. If this is not the case, the color space of the image file
  can be configured in the image settings.

Where can I find those settings ??? Where can I set the color space of images ? In this post it is said that

  Saving to a JPEG or TIFF at 8 bits per channel will apply a nonlinear
  sRGB curve to the data, and may change the internal float format to
  the respective format's storage type. Saving to an EXR will transfer
  the internal reference space buffers unchanged which, by nature of
  EXR, is a linearized float scene referred format.

What does this mean ?? Does this mean the image are saved in sRGB by default but no color profile is attached to the image ? So best to assign sRGB to the image when opened in Photoshop ?

There is a sizable degree of erroneous information listed here; some lacking clarity, while other bits could be classified as entirely misinformation or misleading.

  Where can I set the color space of images?

Complex question that requires a deeper understanding of colour management and in particular, how OpenColorIO is designed, but the short answer is from the UV Image Viewer's Properties panel.

  Does this mean the image are saved in sRGB by default but no color
  profile is attached to the image ?

If you do nothing to the default configuration, yes.

  So best to assign sRGB to the image
  when opened in Photoshop?

Yes.

  How is Blender saving the images ... with to without color profile?

Yes.

  And is that sRGB?

Complex question, but simple answer is “Yes.”


How can unused tracks be removed from the NLA? With autokeying enabled I accidentally moved a few objects, unfortunately they now appear in the NLA editor. I removed the actions saved and reload but I can't get rid of the entries.

This behavior has been changed after 2.66a. Just tried to discuss with the designer. As explained, it is one of the main ways to prepare some places to add NLA strips from pre-made actions, and got its advantages, too.

To make them invisible, click the third toggle on the header to exclude them from displaying.


Where is emission color in Cycles Render Engine with reference to my previous post (Equivalent color settings in Blender with Autodesk Navisworks), I am changing the render engine from Blender Render to Cycles Render.

I could not find the settings for Emissive color in Cycles Render.

I managed to find Emissive color in Blender Render:

I have searched for Emissive color in Cycles Render Manual, but to no avail.

Where can I set the Emissive Color in Cycles Render?

Thank you.

In Cycles Render you find the emissive material by
a) > Properties Editor > Material > Surface > Use Nodes > Surface Emission or more easily:
b) within the Node Editor by > Shift+A > Shader > Emission. Connect this to the Surface input of the Material Output node.

Or give this Add-On a try:
https://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/Material/Blender_Cycles_Materials_Converter


Why can't I get a clean result from cycles? In 2.79, I could get easily acceptable quality from the native renderer. I'd like to move to 2.80 but can't get a good quality render from cycles and eevee is far worse.

The files below are an old practice image that used many of the basic techniques that I needed to practice. I'm more interested in technical drawings but needed something a bit more capable than the free Sketchup offered.

http://www.bcae1.com/temp/blender%20help/

Can I get a clean render (no fireflies?), proper clear transparencies, clean reflections in cycles? In blender render, it was so simple. In cycles, I'm having no luck.

To make it easier to show new settings:
http://www.bcae1.com/temp/blender%20help/hydrauliccylindertransparenttube01.blend

This will allow anyone helping to change the materials for the tube without having to try to go through the mess I have on the larger file.

Thanks to all who posted.

I think, for now, I've found a solution that will work for me (Radeon ProRender). The controls work as I expect. I'm sure that Cycles works as well or better since I've heard very little about the Radeon renderer but I can make ProRender do what I need it to do for now where Cycles just baffles me. Thanks again.

Either crank up your samples or try denoising with AI or Photoshop / AfterEffects.
The former takes a little longer to render, the latter produces artifacts at times.

I am not too sure about the current implementation of denoising into cycles, but there is an addon called dnoise you could try out. Otherwise go into the "Properties" Editor, into the "Render" Context and and put a higher value into the "Render" textfield under "Sampling".

The thing is, that Cycles does a lot more realistic calculations than BlenderRenderer ever did, so it takes longer to produce a clean result...


How to make water flow from the certain areas of an object? How to make water flow from the certain areas of an object?

I am making an animated character, made of water.
I was going to make the illusion of water, with shaders and different deformations, but I also wanted to make that the water drains from the character to the ground, so I started thinking about the possibility of making some areas of the character as the source of water.

It's better to use a special object to be the emitter, by duplicating the part of the mesh you need the fluid to emitt from Shift + D your selection in edit mode, then  P and choose "Selection" to separate the mesh to a new object, assign the particles to the new object, position your vertices were you want the water to emitt.
You can use "Vertices" option instead of "Faces" in the Particles Tab parameters, Under "Emission" panel > "Emit From:". Remember to uncheck the "Emitter" check box if you don't want the emitting object to show in render.

Edit: Adding images for better explanation.


How do I resolve a path with backpaths (..) in the image.filepath? I'm trying to find the directory where an image file for a slot texture is located.  It works fine for most paths, but when the paths are qualified with .. (to back up a directory) it will then crash when I try to use os.listdir.

So, for example, this works if the image path is straightforward (Windows only -- not interested in any other OS since this only runs for Windows):

V:\somepath\geo\this image.png

mypath = mtex_slot.texture.image.filepath
for filename in os.listdir(mypath)

but this fails if the image location includes backpathing:

V:\somepath\geo\..\textures\this image.png

where the directory structure where the file is located is:
V:\somepath\textures\this image.png

The image location works in Blender with back paths -- which is to say specifying it that way in the image path will correctly resolve.  But it will not resolve in the os.listdir function.  So is there a way to read this in Python, or must I parse it myself by writing my own backpath function?

Crap -- I have GOT to stop asking questions until I spend more hours looking for an answer.

Sorry, folks, but os.path.realpath(mypath) works for me.  Sigh.  Nothing to see here, move along.


Using Cycles Render, how do I produce a material with a transparent section of the texture? I have tries a bunch of methods using the nodes and various node configurations as explained in a number of other how-tos and tutorials, and every result is the same, no transparency. The alpha layer of my image is either solid black, or solid white, not transparent.

How to I creat a material using nodes with the Cycles Render using a texture image (.png file) which a center area that is transparent (alpha channel).

Make sure you are using mixing transparent node with your material. And that the Transparent node is in the top input of the mix shader.

The Blend file I attached is the file the screenshot is from.


How to use Blender object rotation style using Maya Navigation? I just switched to Blender Navigation to test a few things and shortcuts, and noticed Blender Rotation style is different than Maya, when I press R it goes in Rotation mode, when I press R again it goes in trackball rotation mode I can see this could be useful in some situations, but how do I use this in Maya Navigation
mode, any shortcut or command for this ?

I don't know how it work in Maya, but in Blender you have this options:

1: Turn ON "Transformation manipulate"

2: Use this shortcuts: (I recommend)

"R" and after "X" = rotation arround X axis in global coordinates
"R" and after two times "X" = rotation around X axis - in local coordinates
"R" and after "SHIFT+X" - for rotate around Y and Z axes (no X)

This work for all axes obliviously and for "G" - grab, "S" - scale and "R" - rotation.


How do I type on a Bézier curve? How can I get an effect like this?

This is what I have right now:

I'm trying to make the words follow the line so I can curve sentences downward.

Credits: https://www.behance.net/gallery/60396931/BLACK-SERIES-1-POSTER-COLLECTION

You could do it this way:

Create a spiral with shift A > Curve > Curve Spirals > Archemedian (maybe it needs the Extra Objects addon?).
Play with the parameters on the bottom of the T panel (left of the 3D View), give it a Height value.
Put the origin of the spiral on its bottom. Check the direction so that it goes up.
Keep the spiral selected and in the Properties panel > Data > Shape > Twisting dropdown menu > choose Z-up, so that the text will stand up.
Create your text with shift A > Text and type what you want in Edit mode.
Convert your text to mesh with alt C > Mesh From Curve.
Put the text at the same point as the spiral origin.
Give your text an Array modifier.
Give your text a Curve modifier with the Spiral as Object.
Now play with the Array Count, with the Array Relative Offset, with the Curve Deformation Axis, and with the text object rotation, until the text correctly follows the spiral.
Maybe your text mesh will need some work and additional edge loops so that it bends correctly.


Splitting a Character's Body I've gone crazy to find the solution to my problem, but I can't get anything clear. I want to separate my character's body into parts so I can hide them in the Unity project I work on. But some lines appear in the cuts that I have made in the character that are also seen in Unity. I asked Unity about the subject, and one answered me, saying something about what I have to preserve the normal ones before cutting, this way the cuts will not be noticed. Is there this function or similar in blender2.8? Is there any other method?

When you split a smooth shaded object, the normals are recalculated. Their direction is depending on the vertex before and the one after each vertex. If you take the vertex "after" out of the equasion, the normals at the very edge will be modified. Hence the lighting will be treated differently exactly where the split has occured (which is what you are seeing).

The ppl. in the Unity forums were correct, however I am unaware of a method of splitting an object directly and keeping the normals at the split.
Using multiple materials (can be the same material in multiple slots) does pretty much that, but internally, not visibly.
So a crude approach could be to hide submeshes in Unity.
Have not tried this, since most ppl. don't split naked characters, but rather hide the seams, but:
Split your object by material slots (assigning them to the faces in edit mode).
In Unity use:
myMesh.GetTriangles(mySubmeshIndex);
to show only the triangles that belong to the body part.
There might be a better solution, but not one I can think of right now.


How to create Light smear in blender animation In this picture, I'd like to make Light smears to express much more speeds in animation. How can I do this?

The glow can be created by using a glare node in the compositor.  Since the second accomplishes most of what you want, here's an example:
I created a simple sphere and give it two materials, a shiny dark blue, and a white emission:

dark blue shader:

emission shader:

This is all basic stuff, of course.  Next I rendered the image with F12 and then I went to the Compositing work space and created the glow:

The result looks like this:

You can control the strength and size of the fog flow of course.


How do you control the number of loops on a bevel of a path? Changing the resolution just doesn't do the trick. How can I control the bevel on a path to change the number of loops it uses to comprise the bevel?

It is in the resolution of the host path, not of the target bevel path.


How to correctly use the Collada exporter? I finally managed to finish creating a complete character in Blender and i wanted to export it for the Godot game engine, so i wanted to use Collada (i tried both the Blender default exporter and the better Collada exporter from the Godot website) as my exporting format but when i tried to export i stumbled upon some weird errors that i couldn't really find an answer on google. Here is an image with the errors i'm getting :

I imported the .dae file into the Godot engine to see if it has any problems and the shirt of the character is invisible but only the front side and when i play the idle animation the hands deform weirdly.

I would appreciate if you guys could help me with this or tell me what i should search to fix and avoid these errors in the future.

Try applying scale, rotation and location(Ctrl + A) on the rig and then the mesh, while in Object Mode.

You'll have to redo the animation


How to make the measuring grid larger? When starting the blender, there is always a cube on the floor. The floor is actually a grid. My question is how to make this grid bigger so that we can measure big stuff?

You can change the size of the grid to accommodate your needs, or you can change the scale of the whole scene.
To change the scale of the grid in the 3D view.
For 2.8X Open the overlay controls.

And change the scale and number of subdivisions.
For 2.7X
Press N to reveal the properties shelf.
On the Display section you can change the grid floor number of lines and scale.
The left side of the screen will show info on the scale of the units used.
From the wiki:

Lines defines the number of lines that will make the "floor grid" up. If N is the number defined, there will be a total amount of N/2 lines at each side of X and Y axes. For odd values of N, the amount of lines will be rounded down.
Scale defines the distance between grid lines, either in the "floor grid" and the infinite grid.
Subdivisions defines the amount of lines into which the infinite grid should be subdivided. Level of subdivision depends on zoom, in predefined orthographic views.

To change the scale used for the scene:
Other way to deal with large (or very small) objects is changing the scale on Properties->Scene->Units->Scale

Note that changing the scale for the scene in the Units Section will affect the size of the grid, but changing the size of the grid in the 3d viewport will not change the scene's scale.
Besides the floor grid, Blender has some built in measuring tools that you might find useful.
For 2.8, in Edit mode (Tab), open the Overlays section and you can choose to enable the boxes for Edge Length, Edge Angle, Face Area or Face Angle.

For 2.7X, in Edit mode (Tab), enable the numeric panel (Kbd>N) and look for the Mesh Display section, to enable display of edge and face info of an object.

When dealing with very large or very small objects they might seem to disappear from view due to the clip distance on the viewport. If that happens you might need to change the start and end clip values.
See this question: Why does part of my model disappear when I zoom in on it in the 3D Viewport?


No "obstacle" option in fluid type I'm trying to make gas flow through a tube.
I've watched many videos demonstrating similar procedure.
And they simply add a cube or any other object, go to the 'physics properties', click 'fluid',
then choose type as 'obstacle'

In their screens, the options are "Control, Particle, Outflow, Inflow, Obstacle, Fluid, Domain, None".

With my Blender 2.82, if I follow the same procedure, I see "None, Domain, Flow, Effector".
Where is it?

That would be the new updates in Blender 2.82 involving mantaflow etc.

I'd suggest that you go look for Mantaflow tutorials such as this one by CG Geek:

However, here's a quick summary of the four options that you have in 2.82:

None - Nothing.

Domain - The area that the fluid simulation stays within. None of the smoke/liquid will ever leave this area.

Flow - This is the actual smoke/liquid/fire emitter. You can change the type and additional settings within the settings of the Flow type.

Effector - These are your obstacles to the liquid simulation.


Rendering Clear Glass with Shadow Catcher and Transparent Background (Glass looks white instead of clear) This is the coffee cup that I made and it is rendered with the cycles engine on top of a white plane:

This is the coffee cup that I made and it is rendered with the cycles engine on top of a white plane acting as a shadow catcher. AKA for the plane I selected "Object Properties" > "Visibility" > then checked the box "Shadow Catcher". I also checked the box labeled "transparent" under "film" in the "Render Properties" tab:

I am trying to composite this cup into a video (using davinci resolve) so I need the background to be transparent but the cup just ends up looking white instead of clear. Is there a way to make the cup have a shadow while still being mostly transparent?
Btw, I'm using Blender 2.83.5

Under "Film" also check "Transparent Glass"
You must use a Glass Shader on your glass, adding a Gloss Shader mixing a with Fresnel works, too.

It is possible to save the alpha channel separately.


Disable the 'see though mode' in edit mode I am currently modeling an ear and it becomes very hard to see some vertices

I know that I could hide some geometry in the background, but is it possible to completely disable the see though mode so that I only see the vertices on the surface?

Enable limit selection to visible in the bottom tool bar.


Rendered textures different to 3D View I UV smart unwrapped the model to a layout and applied the relevant materials and textures. In 3D View, the textures look fine (as shown above). However on rendering, the brick and wood textures become distorted (see below) (notice the roof is fine). What is the cause of this?

I have been asked to detail the process by which I apply a material / texture so here it goes. Firstly, I smart unwrapped the model as shown.

I then create a new material (in this case a brick material).

I then add my brick texture to the material as shown:

I do some mapping of the X/Y coordinates in order to resize my image texture to fit the face.

Finally I select the face to which I wish to apply the material and hit assign.

Occassionally, the bricks will have the wrong rotation and so I will rotate the UV island within the UV layout in order to have the brick texture rotate into the correct position.

In 3D view, the textures look perfect, when rendered, something is going very wrong.

After some playing around, I've identified my mistake. The XYZ coordinates under 'Mapping' in the texture properties were different for the distorted textures. I corrected these so that the order of the XYZ is the same for all textures. The image now renders correctly.

Example:

Bricks (distorted) was:

Roof (not distorted) was:


Is it possible to animate alpha of a dupligroup? I have a model, in its own blend file.  I link it into another file.  At some point in an animation I want it to gradually disappear. I've gone looking for ways to do this, with no luck. Is there a way to do this in blender-render?

No. There's not.  I ended up building two scenes, one with the objects, one without, and using a transition between them.  It isn't exactly what I was looking to do, but it works well enough.


Export fluid simulation data INSIDE file I am planning to use a render farm (render.st) to render an animation containing a mantaflow fluid simulation. Blender stores fluid simulation data outside of the .blend file, which I am unable to upload.
The "Automatically pack all into .blend" feature doesn't seem to pack the fluid data, as my fluid data folder is a whopping 14.4GB while the .blend file after packing is only 14.4MB.
Is there a way I can send mantaflow fluid sim data to a renderfarm?

The answer to that question is in our (RenderStreet's) knowledge base, search for 'baking'. This is a quote from the first section in the article:

For uploading there are 4 options:

Use our plug-in. The plug-in will collect automatically all baked caches and all project assets and will upload them to our servers. You can download the plug-in from the link in your RenderStreet account
Zip the entire folder and upload via the "add render job page". You'll receive an error message saying that we were not able to find the blend file in the archive. In the process, the archive will get unzipped and then you'll be able to find the uploaded folder at the bottom of the page, in the FTP files section.
Via Dropbox or another cloud storage account .
Via FTP .
Also, when having a question regarding our service, asking our support will get you an answer :)


Why does my model look messy and contains dents when I turn on the multi-resolution modifier? I wanted to see what my model looked like so far in sculpt mode with the multi-resolution modifier and it looks like total garbage. I'm new to blender so my model does have a lot of overlapping vertices and edges but I'm not sure that's the reason. During my last attempt, I thought it was because the image was asymmetric so I used mirror modifier to make the model totally symmetric. I know that the model is very messy in it of itself, but I'm just trying to narrow the problem to specifics. Honestly, I have no idea what's happening.

Here's the file I'm struggling with:

Before I start from scratch AGAIN could someone give me a clue as to why this is happening?

Thanks

There are 3 main issues that can cause problems for Catmull-Clark subdivision (the algorithm that both MultiRes and Subsurf use).

Non-quad faces.  When modeling in general try to use all quads, i.e. faces with 4 sides.  Subsurf requires quads or tris (3-sided faces), so any non-quad faces will be automatically triangulated which can give undesirable results.  An occasional well-placed tri can be fine, but in general stick to quads.

Inside geometry.  Geometry inside a mesh should be avoided at all costs.  Inside geometry occurs when an edge is shared by more than 2 faces.  This can cause major issues for Subsurfing.  (It seems to be the biggest problem in your case.)

Stretched faces.  Try to avoid extremely non-regular faces, i.e. long, extremely non squarish or equilateral-trianglish faces.  These can create some messy stretched looking and pinching in the resulting mesh.  Your faces don't have to be perfect regular polygons, but long skinny faces will cause problems.

As an aside, your normals are a bit messed up (indicated by the darker faces).  While normals don't play a factor in Subsurfing, messed up normals can cause a lot of other problems.  After removing inside geometry you should select your entire mesh and hit Ctrl+N to recalculate the normals.


Blender Image compression from command line I am running blender from command line and using some scripts.In order to reduce the output size, I'd like compress the .png output file.I understand that this can be done in Blender GUI. However, I am struggling to find a way of doing it in command line or in script file.


Can't install latest blender on windows I go to the blender website
Select the 64 bit US instillation for my Windows 7 Desktop Computer.
After downloading I open the Blender Set Up Wizard and I am given three options: Change/Repair/Remove
I have tried to Change and Repair but once completed if I open Blender the Update has not been installed and the blender is still the older version.
I am considering uninstalling everything and trying again but I have several projects on the current blender and I can't risk loosing them

Can anyone help explain to me what steps I can take to safely install and apply the latest version of blender. I have version 2.66a and I'm trying to get the latest 2.76b.

Any help would be greatly appreciated!

From the manual:

Download the .zip or .exe for your architecture (64bit is preferable if your machine supports it).

The .exe will run an installer to choose where to place Blender and to configure MS-Windows to have an entry on the menu and to open .blend files with Blender. Administrator rights are needed to install Blender on your system.

Note:
With .zip you have to manually extract Blender to the desired folder, where you can double-click the executable to run Blender.

There is no installer to place Blender on the menu, but there is also no need for administrator rights. With this option it is possible to have multiple versions of Blender without conflicting, as they are not actually installed on the system.

https://www.blender.org/manual/getting_started/installing_blender/windows.html


Camera angle should follow path angle (I'm a blender beginner but know a handful of techniques with other similar programs/systems)

I've created a NURBS to make a tracking shot. Creating a follow path object constraint on the camera lets the camera follow the track in terms of translation, however the rotation of the camera is fixed this way. In other words the camera should look to the exact way the path currently points.

I'm pretty sure this is possible with blender (everything should be possible with blender :), I just don't know which object constraints I have to use in order for the camera to do this.

Set Parent To -> Follow Path

This effect can be achieved with the following method:

Add a curve for your path: SHIFTA -> Curve -> select a curve
Edit your curve to be your desired camera path
Make sure you have the green frame cursor set to the frame on the Timeline you want to begin having the camera follow the path
Select the curve and in Edit mode, select the point of the curve you want to be the first place you want the camera to be
Then snap the 3D cursor to that point: SHIFTS -> Cursor to Selected:

Now select the camera, then snap it to the 3D cursor: SHIFTS -> Selection to Cursor:

Adjust the rotation of your camera so that it looks forward along the path
Now first select the camera, then hold down SHIFT while selecting the path, then make the path the parent of the camera with the Follow Path option:  CTRLP -> Follow Path:

(NOTE: The order you select the two objects is very important when setting parent/child relationships: first select the child, then the parent)
Now when you play your animation, the camera will follow the path and stay oriented to the direction of the path:


Cycles: Glass not rendering as transparent in CPU mode AMD Ryzen 7 2700 8-core 4.1, 32 GB RAM, RTX 2060 (6GB VRAM)
I have a glass and transparent BSDF set up correctly in Blender, and the texture set to alpha clip, and alpha hashed for shadows. The glass works perfectly in GPU mode but is not showing the image behind it in CPU mode - simply switching from one to the other.
The scene, even with optimisations, is still too large to render on the GPU for my card. Simply switching from GPU to CPU to allow for rendering the image results in the glass/transparnet shader no longer being see-through.
Is this a bug or is there something I have missed?

This may or may not help your problem but you shouldn't use glass and transparent shader mix, instead, for realistic results, use Principled BSDF with transmission of 1, if you're using eevee, you will need to enable screen space reflections and refraction in render settings, check refraction checkbox in material settings and set refraction depth to something other than 0.


How to unwrap part of a body to a single material I imported an FBX (from Character Creator 3) that had 8 textures associated with one mesh.  The FBX imports and looks great.

I want to look at the UV mapping for the "head" material to see how it is unwrapped. (I plan on wrapping the texture on another model).

Looking at the mesh in the outliner and property panel shows it has 8 materials.
Looking at the vertexes in the properties panel shows that is has only one UV map.

Selecting the mesh and selecting the "head" material and viewing the unwrap in the Texture view, shows the unwrap for all 8 materials simultaneously.

I can't select "just the head", as it appears to be fully part of the body.

I'm missing something that's probably obvious. How can I view and edit just one materials UV?

OK. The obvious part I missed is that I need to just select the vertices. I still don't see how it has a single UV map that spans 8 different materials, but that doesn't actually matter for what I'm doing.


Model is moving while playing animation I have re-targeted an animation on my model and except the movement everything worked.

Problem is that model moves forward while the animation plays, it has to be stationary.

Here is example GIF:

Is there an option to fix this?

Here is the Blender file:

I've played around with the file, to me it seems that the "rigpelvis bone" has X and Y location keyframes that make the whole model "move". By muting them it seems better (but it's still not perfect to me... feet are still sliding, maybe they need to be animated differently... (I'm not a rigging expert)


How do I fix an out-of-bounds object? You know how if you move an object too far off within your blender space it starts to glitch out and moves to spaces that are in large numbers, like "D:78453876956487 along global X," well that's a problem that I'm having and was wondering if there is any shortcut button to center the object to the 3D cursor or something?

Select your object, use Shift+S, then select "Selection to Cursor" in the menu.


How to model a simple semi-organic form like this effectively? I tried to recreate a simple ribcage model from these reference images:

I ended up achieving something similar with crease edges and subdiv modifier:

But it was basically modeling by trials and errors. I just manually move vertices after vertices until they somehow resembled the reference. It took me ages and I think if I do it again it won't be much faster.
How could I approach this kind of task effectively?


White ceramic- irrespective of lighting In blender, we can get a green reflective color irrespective of the lighting:

or a yellow ceramic :

But I've been thinking of a way to get white ceramic like these cups, irrespective of the lighting. We could fake through the use of HDR lighting or using the compositor, to seperately render out the cups and use a background. But, what would be a way to do so irrespective of the lighting.So, that we could take the same cup(or objects), to a bunch of different scenes and not get bugged with making adjustments. In a single scene, too much of lighting would occlude out the details. So, I'm really confused how to get this results.
All I get is a dull gray :

Please note that the main point of it is to be irrespective of lighting.

Environment texture:

First of all you'll need some Environment Map. I suggest to use HDRI imitating photo studio setup. You can find many of them, even for free.

After selecting one change Strenght accordingly to your needs. And you can see our environment.

Background:

To get gray background, or any other color create plane and extrude it with nice subtle curve.

Material:

I'm using simple Diffuse/Glossy mixed by Fresnel but you can go with any other setup. Remember that default color in Blender isn't pure white.

Blend file:

Here it's my blend file with HDRI map packed.


Where to report and discuss UI "bugs" and inconstancies? As UI/design inconstancies are not considered bugs (rightly so), they are off topic on the bug tracker.

Is there a place where these sorts of things can be reported and discussed?
Or a place to write issues/ideas where the new UI team will read them?

If you have a full proposal (detailed design docs), it should be ok to open a task on http://developer.blender.org/ and discuss there (staff only!)

You can discuss with the community at http://blenderartists.org/ to generate ideas, exchange mockups and find to a practical proposal. Then it's time to write it down on a wiki page for example.

Implement the ideas or find someone who does, then submit something working (a patch/diff) to the tracker. If there's no one to actually code it, it will likely be considered a feature request and not gain much attention there are just too many and not everyone will agree on a certain solution...


Customizing array objects with shared material I have an array of objects that share the same material. In addition to several other nodes, the material setup has a texture node hooked up to a mapping node. I would like to set the mapping rotation of the texture node independently for each object  in the array and keep everything else in the material the same. Is there anyway to do this?

Figured it out. In object mode, select the objects that need to be unlinked. Press U, select Materials+Tex.


What draws the Constraint menu completely? I am working on recreating the UI for displaying constraints inside the tool shelf. What does not work is listing the added constraint values.

Below is the code I wrote based on what I found inside the constraint py file.

# CONSTRAINTS ---------------------------------------------------------------------------
class Constratints(bpy.types.Panel):
    bl_label = "Constratints"
    bl_idname = "Constratints"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'TOOLS'
    bl_category = "Modeling Toolbox"

    @classmethod
    def poll(cls, context):
        return context.object and context.object.data

    def draw(self, context):
        layout = self.layout
  #      con = DATA_PT_constraints(context)
        ob = context.object

        layout = self.layout
        row = layout.row()

        row.operator_menu_enum("object.constraint_add", "type", text="Add Object Constraint")
        for con in ob.constraints:
            box = layout.template_constraint(con)
            if box:
                getattr(self, con.type)(context, box, con)

#        for con in obj.constraints:
#            self.draw_constraint(context, con)

This is the code I used to create this for modifiers:

# MODIFIER ---------------------------------------------------------------------------
class ObjectModifier(bpy.types.Panel):
    bl_label = "Modifiers"
    bl_idname = "ObjectModifier"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'TOOLS'
    bl_category = "Modeling Toolbox"

    @classmethod
    def poll(cls, context):
        return context.object and context.object.data

    def draw(self, context):
        mp = DATA_PT_modifiers(context)
        ob = context.object

        layout = self.layout
        row = layout.row()

        row.operator_menu_enum("object.modifier_add", "type")
        row.operator("object.make_links_data", text="Copy Modifiers From").type="MODIFIERS"
        for md in ob.modifiers:
            box = layout.template_modifier(md)
            if box:
                getattr(mp, md.type)(box, ob, md)

From the code in  startup/bl_ui/properties_constraints.py .
ConstraintsButtonsPanel class has a draw method defined for each constraint type, for example TRACK_TO

class ConstraintButtonsPanel:
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "constraint"

    # ....
    def TRACK_TO(self, context, layout, con):
        self.target_template(layout, con)

        row = layout.row()
        row.label(text="To:")
        row.prop(con, "track_axis", expand=True)

        row = layout.row()
        row.prop(con, "up_axis", text="Up")
        row.prop(con, "use_target_z")

        self.space_template(layout, con)

#....
class OBJECT_PT_constraints(ConstraintButtonsPanel, Panel):

Notice the OBJECT_PT_constraints class inherits the ConstraintButtonsPanel class, giving it all the attributes defined therein.

ConstraintsButtonsPanel.TRACK_TO is the layout code for a track-to constraint, without this, the line (when con.type == 'TRACK_TO')

getattr(self, con.type)(context, box, con)

will result in the error

AttributeError: 'Constratints' object has no attribute 'TRACK_TO'

A quick fix would be to import the ConstraintsButtonsPanel class and use it in the getattr(...) call, like so

import bpy

from bl_ui.properties_constraint import ConstraintButtonsPanel

class Constratints(bpy.types.Panel):
    bl_label = "Constratints"
    bl_idname = "Constratints"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'TOOLS'
    bl_category = "Modeling Toolbox"

    @classmethod
    def poll(cls, context):
        return context.object and context.object.data

    def draw(self, context):
        layout = self.layout
  #      con = DATA_PT_constraints(context)
        ob = context.object

        layout = self.layout
        row = layout.row()

        row.operator_menu_enum("object.constraint_add", "type", text="Add Object Constraint")
        for con in ob.constraints:
            box = layout.template_constraint(con)
            if box:
                getattr(ConstraintButtonsPanel, con.type)(ConstraintButtonsPanel, context, box, con)
                #getattr(self, con.type)(context, box, con)

bpy.utils.register_class(Constratints)


Achieving wipe effect in video with (motion tracked) mask revealing 3D object An object in a video clip should be tracked to move a mask across the screen, revealing a 3D object (extruded text). Imagine a shot of a sheet of paper on a desktop. The paper is pulled out of the view sideways, revealing the rendered object which appears to be on top of the desk.

So I imagine I need to composite the video in the background, and an animated mask on top of the text, so that the visibility of the text (= opacity of the mask) is zero where the paper is in the video, hiding it.

What I have: a video clip in the Timeline, an extruded text in the Scene, and two nodes "Render Layers -> Composite" in the Compositing Editor.
When Rendering, the result shows only the video, but not the object.

I'd be happy with a short outline of the easiest steps I need to take to achieve what I want. But a few pointers to the tools I need to use or a rephrasing of what I am trying to do in the proper terminology would help in searching the information on my own.
Motion tracking is not really necessary since it is a short clip and I'd gladly learn how to animate the mask manually.

I am using Blender 2.78a on Windows.

If I'm guessing right, you're moving a sheet of paper in a previously taken video to uncover some 3D (extruded) text that's sitting in Blender's 3D window.

I've done it here with a single animated masking plane.

The first example is the (pre-recorded) video I manufactured for the purpose.

The second is the end result when using the first as the bkd video and overlaying it's paper sheet with a matching sized plane. (in Blender's 3D work area)  The plane is textured with a screenshot of the video's paper sheet.

The text is there all the time.  It's the copycat paper (plane) that's hiding it from view.

The plane moves in unison with the video's paper using keyframes and shape keys to match it's changing dimensions as the frames progress.

It is in fact manual tracking and is not difficult in many circumstances.

Once the text is in view, the masking plane is dispensed with and the video can proceed on it's own.

This is but one solution.  Another might be to use Blender's tracking and inbuilt masking.