#version 440 layout(vertices = 3) out; layout(location = 0) in vec3 inColor[]; layout(location = 0) out vec3 outColor[]; layout(location = 1) patch out float a_per_patch_output_variable; void main() { if (gl_InvocationID == 0) { gl_TessLevelOuter[0] = 4.0; gl_TessLevelOuter[1] = 4.0; gl_TessLevelOuter[2] = 4.0; gl_TessLevelInner[0] = 4.0; } gl_out[gl_InvocationID].gl_Position = gl_in[gl_InvocationID].gl_Position; outColor[gl_InvocationID] = inColor[gl_InvocationID]; a_per_patch_output_variable = 1.0; }