- use in/out instead of attribute/varying
- use named output instead of gl_FragColor
- use texture() instead of the multitude of older texture sampling functions
The #if __VERSION__ == 120 paths (needed on Mac) will be removed after we switch to 3.3 core profile.
Part of T49165 (general OpenGL upgrade)
Builtin names staring with gl_ will not be available in core profile. Same with the ftransform function. New matrix API provides the same names minus the gl_ prefix.
Part of T49450
Beside the obvious ARB -> GLSL change, the texture slicing algorithm had
to be rewritten.
Although this new algorithm has the same behaviour as the old one (view
aligned slicing), it works with an arbitrary number of slices (which
could eventually be set by the user), which means we can preallocate the
buffer. The previous algorithm would slice from the begining to the end
of the volume's bbox, and draw the slices as it generates them.
Also support for ARB program was removed.
Patch by myself, with some minor fixes by Brecht.
Reviewers: brecht, #opengl_gfx
Differential Revision: https://developer.blender.org/D1694
