* renderer: rewrite glyph cache
This commit splits the current GlyphSet-based system into 2 caches,
CharMap and GlyphMap, which maps codepoints -> glyph IDs and glyph IDs -> glyphs respectively.
Each GlyphMap contains a number of GlyphAtlas mapped by their width,
and each GlyphAtlas has a list of surfaces with the same width.
Surfaces within the GlyphAtlas acts like a bump allocator, but is flexible
enough to allow older GlyphAtlas surfaces to be recycled.
GlyphMetric now contains atlas_idx and surface_idx, which points to the correct surface.
Since GlyphAtlas supports rudimentary packing & allocation, we no longer render whole
GlyphSets and this speeds up rendering in most cases.
Tab width is no longer set with the hacky "modify the GlyphMetric" hack.
* renderer: set natlas to 0 after freeing
* renderer: fix printf warning
* renderer: fix memory leak
* renderer: better whitespace rendering
* renderer: fix ubsan warning when casting ints
* renderer: fix tab handling
There's a bug with inconsistent tab widths caused by fontgroups.
* renderer: fix glyphs being loaded over and over
* renderer: add glyphmap size
* renderer: store per-surface offset_y and use it to find best-fitting surface
* renderer: fix MSVC compiler error
* renderer: remove return value from ren_font_glyph
* renderer: refactor xadvance calculation
* renderer: fix double free SDL_RWops if FT_Set_Pixel_Size fail
* renderer: always try .notdef before U+25A1
* renderer: disable ren_font_dump yet again
Accidentally commited this change.
* renderer: remove unused imports
* renderer: fix double free with FT_Open_Face
* renderer: return SDL_Surface in font_find_glyph_surface
* renderer: bring back metric flags for future extension
* renderer: refactor xadvance calculation into macro
* renderer: fix comment
* renderer: store GlyphMetric directly in the surface
* renderer: remove duplicated comment
* renderer: rename font_find_glyph_surface to font_allocate_glyph_surface
* renderer: refactor glyphmetric retrieval into an inline function
* renderer: do not render glyphs with bitmap set to null
This is a weird edge case, but at least it shouldn't crash
* renderer: refactor face metric code into its own function
* renderer: actually check if glyph fits in surface
* renderer: rudimentary support for non-scalable faces
At least it won't render nothing on the screen
* renderer: check for font_surface instead of metric directly
This is safe and shorter
* renderer: fix indentation
* renderer: rename GLYPH_PER_ATLAS to GLYPHS_PER_ATLAS
* renderer: rename all GLYPH_PER_ATLAS correctly
* renderer: make utf8_to_codepoint slightly more durable
* renderer: fix compiler unsigned cast warning
27d95f63cb