ShaderMaterial, why varying rather than out?

I’m working through the OpenGL manual on GLSL and the syntax for passing a variable from the vertex shader to the fragment shader is to use the word ‘out’. When using ShaderMaterial we use the word ‘varying’. Why the difference?

Different spec, webgl 1 conforms to opengl es2. If you look up the reference for that you’ll find the familiar syntax.

1 Like

Thanks for that.