gles3 Emscripten

[Jonathhhan]

If I add #include <GLES3/gl3.h> for Emscripten in ofConstants.h I can use additional stuff like texture3D. (still the ofxVolumetrics example https://github.com/timscaffidi/ofxVolumetrics does not work with Emscripten - maybe I made some mistake porting the shader to GLES)

[ranjithshegde]

@Jonathhhan Are you removing GLES2/gl2.h? How do you handle GLES3/gl3ext.h?

I am trying to use some GLES3 features and failing because the browser complains the feautres I need are only in GLES3 I am even specifying gl version to be 3 in main.cpp