[require] GLSL >= 1.20 [vertex shader] void main() { gl_Position = gl_Vertex; } [fragment shader] #version 120 uniform vec4 a[3]; void main() { vec4 b[3] = a; gl_FragColor = b[2]; } [test] uniform vec4 a[2] 0.0 1.0 0.0 0.0 draw rect -1 -1 2 2 probe all rgba 0.0 1.0 0.0 0.0