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Splitting this out from the Parley work as requested. This removes
`FontImage` and makes the font atlas use a `ColorImage`. It converts
alpha to coverage at glyph-drawing time, not at delta-upload time.
This doesn't do much now, but will allow for color emoji rendering once
we start using Parley.
I've changed things around so that we pass in `text_alpha_to_coverage`
to the `Fonts` the same way we do with `pixels_per_point` and
`max_texture_side`, reusing the existing code to check if the setting
differs and recreating the font atlas if so. I'm not quite sure why this
wasn't done in the first place.
I've left `ImageData` as an enum for now, in case we want to add support
for more texture pixel formats in the future (which I personally think
would be worthwhile). If you'd like, I can just remove that enum
entirely.
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Adds support for mipmaps in the `glow` backend.
Should be possible to implement for `wgpu` in the future as well, but
requires a custom compute kernel.
Removes `egui_assert` etc and replaces it with normal `debug_assert`
calls.
Previously you could opt-in to more runtime checks using feature flags.
Now these extra runtime checks are always enabled for debug builds.
You are most likely to encounter them if you use negative sizes or NaNs
or other similar bugs.
These usually indicate bugs in user space.
Exposes support in both glow and wgpu for texture wrap modes
This would be breaking for manual creations of TextureOptions but would
work with the current TextureOptions::NEAREST and LINEAR without change,
keeping those clamp to edge
I wasn't sure how best to expose the options to the user and added
consts for LINEAR_REPEAT LINEAR_MIRRORED_REPEAT NEAREST_REPEAT
NEAREST_MIRRORED_REPEAT
This does not include wrap mode clamp to border as it worked fine with
glow but with wgpu it panics due to Features
Features(ADDRESS_MODE_CLAMP_TO_BORDER) are required but not enabled on
the device, and I thought it was probably best not to try to enable that
feature, but happy to include that functionality also if that is okay to
be toggled

---------
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>