Interleaving draw_rect calls with and without a texture forces every rect to
have its own draw call. In this case it meant that there is a draw call for every single
tile in the atlas. This change makes it so the renderer can batch draw calls
which reduced the draw call count by a factor of 512
This allows using texture_2d_get on all platforms which is needed for the get_image function
This commit also fixes some OpenGL warnings on the Web platform that came from attempting to map a buffer with zero length
This removes the countless small UBO writes we had before
and replaces them with a single large write per render pass.
This results in much faster rendering on low-end devices
but improves speed on all devices.
Fixes include using proper depth buffer format in 3D (this had previously been fixed already but the changes were lost in a rebase), Remove unused lighting and shadowing code in 2D, and update 2D UBOs using glBufferSubData so that they remain the appropriate size.
At this time, it works best in the Vulkan Renderers as they support using multiple samplers with the same texture.
In GLES3 this feature really only allows you to use the screen texture without mipmaps if you want to save the cost of generating them.
Implement built-in classes Vector4, Vector4i and Projection.
* Two versions of Vector4 (float and integer).
* A Projection class, which is a 4x4 matrix specialized in projection types.
These types have been requested for a long time, but given they were very corner case they were not added before.
Because in Godot 4, reimplementing parts of the rendering engine is now possible, access to these types (heavily used by the rendering code) becomes a necessity.
**Q**: Why Projection and not Matrix4?
**A**: Godot does not use Matrix2, Matrix3, Matrix4x3, etc. naming convention because, within the engine, these types always have a *purpose*. As such, Godot names them: Transform2D, Transform3D or Basis. In this case, this 4x4 matrix is _always_ used as a _Projection_, hence the naming.
Convert method signature parameters to const where it is possible
# Conflicts:
# drivers/gles3/rasterizer_canvas_gles3.cpp
# drivers/gles3/rasterizer_canvas_gles3.h
# editor/plugins/animation_state_machine_editor.cpp
# editor/plugins/animation_state_machine_editor.h
