Follow cl-textrender 6097148: glyph IDs a font lacks drawn as .notdef
Every function that takes a glyph ID answers for one the font does not
have as for its .notdef, glyph 0, so the reference entries say so, the
Errors page drops the rasterizer's error for such an ID and lists it
among what is not an error, and the backends' pages follow. The Fonts
page and the API reference describe face-glyph-count, font-glyph-count
and font-glyph-or-notdef, and font-glyph-id's NIL for a character map
that points past the last glyph, which fallback treats as a character the
font lacks. The rasterizer's remaining error has its new hint.
Follow cl-textrender 60a0b22: FreeType's errors as textrender-error
The raster backend and the glyph atlas report what FreeType cannot draw
as textrender-error: a glyph ID the font does not have, with how many
glyphs the font has, or FreeType's own message otherwise. Errors lists
both, and the backends' pages and reference entries say so.
Follow cl-textrender 9432835: declared types checked on entry
Every exported function declares its arguments' full types, which SBCL
checks as the function is entered, and a constant of the wrong type
makes SBCL warn as it compiles the call; Errors shows both, with the
message SBCL prints. An empty font list given to layout-text is a
type-error now, a span's empty font list still reports itself, and
tab stops must be positive reals in increasing order. The API
Reference says that glyph IDs are below 2^32.
Follow cl-textrender 03ab0f6: no global nickname textrender
The package cl-textrender has no global nickname any more. The
examples run in a package that gives it the local nickname tr, which
Home and Getting Started show, and prose names its symbols in full.
Follow cl-textrender 08f8561: faces, what fonts keep, and :WRAP NIL
Fonts describes faces, FACE-FONT, the fonts and faces freed once nothing
holds them, DESTROY-FACE, and FACE-CACHE and FONT-CACHE. The outlines,
rasterizer images and atlases are kept with the faces and fonts they come
from: CACHED-OUTLINE and CACHED-QUADRATICS take the font, the rasterizer
and the atlases need no releasing, and FONT-ATLAS and FACE-ATLAS give a
font's or face's pages. Laying Out Text and Typography describe :WRAP
NIL and lines cut short, and the references, Errors, Threads and
Lifetimes and the recipes follow.
font-glyph-id, glyph-text-index, the outline cache, map-layout-glyphs in
the raster backend, glyph-region and glyph-image-offset; line-box,
line-content and run-box in place of line and run edges; and
map-layout-fields for distance fields.
The ellipsis takes its fonts from the fallback list, cached lookups and
drawing allocate nothing, font errors name the file, glyph-outline's
tolerance defaults inside the call, and draw-layout returns no values.
Guides to fonts, layout, styled text and fallback, typography, vertical
text, coordinates, carets and selection, glyph outlines and the three
optional systems; recipes; a full API reference for every exported
symbol; errors, threads and lifetimes, the layout pipeline, limitations,
and platforms and testing.
