Draw the TUI's cells as pixels with the symbols' glyphs

vega pixels runs the same scripts as tui --dump and writes each frame as
an image: the view's cells (only those on screen are evaluated) become
glyphs, each drawn once per size with the exact area of its curves, in its
tone's colour on its row's background. No page, no scene in between. A
1920x1350 grid takes 12 ms a frame here, writing the image included.

Symbol files carry the font's line now (format 3: ascent and descent where
format 2 kept zeros), the cell height and baseline; and the build tool takes
fonts in order, later ones filling the codes earlier ones lack: a CJK font
alone drew ambiguous-width arrows two cells wide in a one-cell grid, which
the new check caught, so a monospace Latin font comes first and Hangul after.

1 files changed, 2 insertions, 10 deletions

diff --git a/symbols/symbols-gl.c b/symbols/symbols-gl.c
index c1ce64e..d91a5dc 100644
--- a/symbols/symbols-gl.c
+++ b/symbols/symbols-gl.c
@@ -87,14 +87,6 @@ bool vega_gl_open(VegaGl *gl, char *error, size_t error_size) {
     return true;
 }
 
-/* The pixels a symbol reaches at scale, one more on each side. */
-static VegaPlace place_of(const VegaSymbol *symbol, float scale) {
-    if (!symbol->count) return (VegaPlace){0};
-    int left = (int)floorf(symbol->left * scale) - 1, right = (int)ceilf(symbol->right * scale) + 1;
-    int top = (int)ceilf(symbol->top * scale) + 1, bottom = (int)floorf(symbol->bottom * scale) - 1;
-    return (VegaPlace){0, 0, right - left, top - bottom, left, top};
-}
-
 bool vega_gl_atlas(VegaGl *gl, const VegaSymbols *s, float scale, const uint32_t *wanted, uint32_t count, VegaAtlas *out,
                    char *error, size_t error_size) {
     (void)gl;
@@ -112,7 +104,7 @@ bool vega_gl_atlas(VegaGl *gl, const VegaSymbols *s, float scale, const uint32_t
         uint32_t index = wanted ? wanted[i] : i;
         if (index >= s->symbols) continue;
         VegaSymbol symbol = vega_symbol_at(s, index);
-        VegaPlace p = place_of(&symbol, scale);
+        VegaPlace p = vega_symbol_place(&symbol, scale);
         area += (uint64_t)p.width * (uint64_t)p.height;
     }
     int width = 64;
@@ -122,7 +114,7 @@ bool vega_gl_atlas(VegaGl *gl, const VegaSymbols *s, float scale, const uint32_t
         uint32_t index = wanted ? wanted[i] : i;
         if (index >= s->symbols) continue;
         VegaSymbol symbol = vega_symbol_at(s, index);
-        VegaPlace p = place_of(&symbol, scale);
+        VegaPlace p = vega_symbol_place(&symbol, scale);
         if (!p.width) continue;
         if (p.width > width) width = p.width;
         if (x + p.width > width) { x = 0; y += shelf; shelf = 0; }