OpenGL Programming/Shaders reference

Vertex shader1 Input variables Output variables vec4 gl_Position : vertex homogeneous coordinates in projection space float gl_PointSize : using rendering points, size of the point Fragment shader Input variables vec4 gl_FragCoord : pixel coordinates (x,y) + fragment depth (z) bool gl_FrontFacing : is pixel facing the camera or the opposite direction? (used in two-sided lighting) vec2 gl_PointCoord : when using Point Sprites, position within the point Output variables vec4 gl_FragColor : RGBA color to use vec4 gl_FragData[gl_MaxDrawBuffers] : alternative to gl_FragColor when drawing to multiple buffers References http://www.khronos.org/registry/gles/specs/2.0/GLSL_ES_Specification_1.0.17.pdf OpenGL ES Shading Language 1.0.17 Specification Khronos.org 2009-05-12 2011-09-25