    [noVelocityVsSource, drawFShader], 
                [quadVSSource, blurFSSource]
            ),
            utils.loadImages(["img/webgl-logo.png"])
        ]).then(([
            [program, noVelocityProgram, blurProgram],
            [image]
        ]) => {
            let texture = app.createTexture2D(image, { 
                flipY: true,
                maxAnisotropy: PicoGL.WEBGL_INFO.MAX_TEXTURE_ANISOTROPY 
            });

            const NUM_SPHERES = 10;
            let spheres = new Array(NU