<FragmentName>
- begin (before main())
- main (in main())
- end (at end of file)
- <name> (direct replacement)
For example
// shader.vert
// #include<Screenspace>
#ifdef GL_ES
precision highp float;
#endif
attribute vec2 position;
void main() {
gl_Position = vec4(position, 0, 1);
}
// Screenspace/begin.vert
varying vec2 vPos;
// Screenspace/main.vert
vPos = position * 0.5 + 0.5;
becomes
// shader.vert
varying vec2 vPos;
precision highp float;
attribute vec2 position;
void main() {
vPos = position * 0.5 + 0.5;
gl_Position = vec4(position, 0, 1);
}