1[require] 2GLSL >= 1.10 3 4# GL_ARB_color_buffer_float provides a way to disable vertex color clamping, 5# but without it, the vertex colors must be clamped. 6 7[vertex shader] 8void main() 9{ 10 gl_Position = ftransform(); 11 gl_FrontColor = vec4(-2, -1, 0.5, 3); /* (0, 0, 0.5, 1) */ 12 gl_FrontSecondaryColor = vec4(2, 0.5, 1.5, -0.5); /* (1, 0.5, 1, 0) */ 13} 14 15[fragment shader] 16uniform vec4 arg0; 17void main() 18{ 19 gl_FragColor = (gl_Color + gl_SecondaryColor) * 0.5; 20} 21 22[test] 23draw rect -1 -1 2 2 24probe rgba 1 1 0.5 0.25 0.75 0.5 25