This fixes a few of the bad design descisions of previous shader
iterations. This uses a dedicated class for managing the resources and
uniform locations of a shader program.
Uniforms are also stored in this object which makes a lot more sense
than storing them in the OpenGL state where they had to be reset every
time a new shader was used.
There are still a lot of possible enhancments to make, e.g. by using
uniform blocks and buffers instead of standard uniforms which would make
uniform location handling easier.
Another optimization that I will investigate is reducing the amount or
different compiled shaders by turning some of the current compile-time
defines into bool uniforms.
This uses GL_KHR_debug for exposing debug group information. This is
very useful for tools like apitrace where it's used for assiciating
OpenGL commands with a specific application function.
The groups are created using a utility macro which is removed in release
builds so it should have no impact on the release performance.
Replaces calls to double-precision floating point trig functions with
calls to single-precision floating point trig functions as follows:
cos() -> cosf()
sin() -> sinf()
tan() -> tanf()
acos() -> acosf()
asin() -> asinf()
atan() -> atanf()
This allows the compiler to avoid generating unnecessary instructions
that convert a float to a double and then a double back to a float.
Signed-off-by: Peter Mitsis <[email protected]>