The code was mixing logical and physical sizes, causing glyphs being
doubly scaled down. Instead, this patch introduces:
* Physical* and Logical* euclid length/size/rect aliases
* some extraction traits for getting the scalars in rects/sizes as lengths (until euclid has them
built-in)
* wrapper traits/types for safely extracting the physical font metrics the
compiler generates (i16)
* Fix a bug in the text height calculation where we failed to take the
descent into account
Move the specific data out of SceneItem into separate vectors. This makes the process of
sorting/moving scene items faster (less memory to move) and makes rectangle rich scenes
consume less memory.
This also paves the way for a "SimpleSceneTexture" vs. a more complex texture.
The README.md contains the warning that used to be in lib.rs.
Add README.md files to all internal crates
... pointing to the official public crate to use instead.
Rename internal crates
fixup: README files
fixup rename
