 binding points.

BINDINGS should be a list of the following format:
  BINDINGS      ::= BINDING-POINT*
  BINDING-POINT ::= (resource :SIZE size :OFFSET offset :STRIDE stride)
  resource      --- A vertex buffer
  size          --- The number of elements in the binding, 1/2/3/4
  offset        --- The offset (in bytes) to the start of the element
  stride        --- The stride (in bytes) between the elements

For instance, the following GLSL vertex shader input spec:

  layout (location = 0) in vec2 pos;
  