#25 3D Game Engine Tutorial: Directional Light

Implementation of the "Directional Light " Tutorial:
Part 1:
https://www.youtube.com/watch?v=WIY8tsSoALo
Part 2:
https://www.youtube.com/watch?v=zoZ-1TOy71E

Note:
The Ambient Light is still darker than the one displayed in the
tutorial. I guess is some side effect of the missing
"GL_FRAMEBUFFER_SRGB" apparently not available in WebGL.