#version 150 core uniform sampler2D tex; in Vertex { vec2 texCoord; vec4 colour; } IN; //In the tutorial notes, I've used gl_FragColor for the output variable. This is fine on the uni machines, but //doesn't play very nicely with some intel and amd graphics drivers, due to the gl_ prefix. For this reason, //it's better to use a different variable name - so pick something sensible. out vec4 fragColour; void main(void) { //fragColour = IN.colour * texture(tex, IN.texCoord); fragColour = texture(tex, IN.texCoord); }