Camera3D projection setup not working on Windows

[MarkOates]

In some cases, projection is not changing the context as expected. The exact case has not been isolated, but in Camera3D::setup_projection_on, commenting out these two lines:

   al_set_render_state(ALLEGRO_DEPTH_TEST, 1);
   al_set_render_state(ALLEGRO_WRITE_MASK, ALLEGRO_MASK_DEPTH | ALLEGRO_MASK_RGBA);

...has shown to restore the rendering (without testing for any side-effects).

Some other ideas

• These may have been put in place to ensure depth is handled (in case other procedures disabled it).
• It's possible other parts of the game system may be writing depth values and the remaining 3D rendering is unable to render.
• It's odd that it works on mac but not on windows. Both are OpenGL.

Not there is a similar setup_dimensional_projection that is used in Camera2D and seems to work fine.

There has not yet been an isolated minimal test made. It also could be related to the framework, backgrounds.

[MarkOates]

More detailed doc here: https://docs.google.com/document/d/1V-q_qlUhvK6aAT9Y78ZOZsWUCzlB9mdENM4GxU47DsE/edit

Solution was identified:

SOLUTION: The problem appears to have been related to Frameworks/Full, when the primary_render_surface is rendered to the display backbuffer. At that point, the depth buffer content is unknown, but ALLEGRO_DEPTH_TEST at 0 still allows it to render, while ALLEGRO_DEPTH_TEST at 1 would check for depth, causing it not to render. The problem was fixed by having ALLEGRO_DEPTH_TEST set to 0 in Frameworks/Full before drawing the primary_render_surface to the backbuffer. This appears to have fixed the problem on Windows and the behavior now appears to be aligned.