Useful if we want to reduce the size of gl_video.c further.
To some degree this emulates traditional glDrawArrays() usage. It also
leaves a loophole for avoiding a reupload every time by leaving
ptr==NULL, although this is unused for now.
default_tex_params() and texture_size() are each called only once, so
move inline/reimplement them at the caller.
image_dw/dh were unused. texture_w/h, image_format, and component_bits
were rarely used, and can be replaced. Regroup some other fields.
Rename surface_num to surface_idx, because the former sounded like a
count, and not an index. Move fbosurface_next() closer to its callers
too.
Move the DebugMessageCallback() code to gl_utils.c (also simplify it
by always setting the callback, instead of only when it changes).
This is somewhat messy, because fbotex_init() itself was depending on
some gl_video parameters unrelated to FBO creation (like what scaler was
in use - what the fuck did this check do in this function?), so this
commit does a bit more than moving code around. In particular, the FBO
for the separate scaling intermediate step now always uses GL_NEAREST
sampling, and all FBOs are destroyed/recreated on renderer
reinitialization.
This also moves the function matrix_ortho2d() - trivial enough not to
put it into a separate commit.
Handles stupid boilerplate OpenGL requires you to handle. It's the same
code as in gl_video.c, although if no VAOs are available, the fallback
code rebinds them on every draw call instead of just once.
gl_common.c contained the function loader (which is big) and additional
utility functions (not so big, but will grow when moving more out of
gl_video.c). Just split them. There are no changes other than some
modifications to comments.
wm4