…bject.

Set the texture_alpha uniform for meshes when rendering instead of in
make_renderable, this wasn't a problem before since each object had its
own instance of the shader.

Also removed unused setting of transparency uniform in Webcam.render.

Also added sorting back to front for transparent
objects based on distance to camera

Position, scale and color were not being set when preloading is
disabled since meshes were not yet loaded.
We now keep track of these properties and set them at load time.

Avoid recomputing the camera view-projection, light matrices
and model matrices every time an object is used for rendering.
This noticeably speeds up rendering with many objects.

…ture

get_projection_matrix() was returning the wrong matrix
causing fragment picking to not work correctly.

Moved and unified the logic for drawing other render passes
(shadows, fragmap and depth prepass) inside the Meshes class
since now it needs to ensure that vertex buffers are updated.

- Prioritize jpegs over pickle files when high_quality is set in from_directory.