1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
[require] GLSL >= 1.10 [vertex shader] void main() { gl_Position = gl_Vertex; } [fragment shader] uniform float v; void main() { gl_FragColor = vec4(1.0) * v; } [test] uniform float v 0.5 draw rect -1 -1 2 2 probe all rgba 0.5 0.5 0.5 0.5