Texture Buffers

Texture-buffers allow access to any jit.gl.mesh buffer (position, normal, vertex_attr, etc.) as a 1D texture in the mesh's shader programs, using the texelFetch command.

You can declare a mesh's buffer as a texture-buffer by connecting a jit.gl.buffer to the mesh, setting the attribute texbuf 1 and specifying the name of the buffer to bind as a texture (position, normal, vertex_attr, etc.) using the attribute type. It is important to note that any normal textures will be bound first, and then texture-buffers. Texture-buffers are declared in the shader as samplerBuffer uniforms.

So if you have two texture-buffers patched into a jit.gl.mesh that look like this:

[ jit.gl.buffer @type vertex_attr0 @texbuf 1 ]
      [ jit.gl.buffer @type vertex_attr1 @texbuf 1 ]

then in your shader params declaration you need something like:

<param name="tex1" type="int" default="0" />
      <param name="tex2" type="int" default="1" />
      <param name="texbuf1" type="int" default="2" />
      <param name="texbuf2" type="int" default="3" />

and in the program body:

uniform sampler2DRect tex1;
      uniform sampler2DRect tex2;
      uniform samplerBuffer texbuf1;
      uniform samplerBuffer texbuf2;

This allows you access to the sampled texture for use in the rest of the shader using texelFetch:

vec3 bufval = texelFetch(texbuf1, index).xyz;

where index is an integer between 0 and the buffer width minus one.

For an example patch, check out tb.pl.disco.duck.

See Also

Name	Description
Working with OpenGL	Working with OpenGL
jit.gl.buffer
jit.gl.mesh	Generate GL geometry from matrices
jit.gl.tf