diff options
Diffstat (limited to 'src/ftcrfont.c')
| -rw-r--r-- | src/ftcrfont.c | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/src/ftcrfont.c b/src/ftcrfont.c index ddd3cc9be64..db417b3e77d 100644 --- a/src/ftcrfont.c +++ b/src/ftcrfont.c @@ -84,7 +84,12 @@ ftcrfont_glyph_extents (struct font *font, cache->lbearing = floor (extents.x_bearing); cache->rbearing = ceil (extents.width + extents.x_bearing); cache->width = lround (extents.x_advance); - cache->ascent = ceil (- extents.y_bearing); + /* The subtraction of a small number is to avoid rounding up due + to floating-point inaccuracies with some fonts, which then + could cause unpleasant effects while scrolling (see bug + #44284), since we then think that a glyph row's ascent is too + small to accommodate a glyph with a higher phys_ascent. */ + cache->ascent = ceil (- extents.y_bearing - 1.0 / 256); cache->descent = ceil (extents.height + extents.y_bearing); } @@ -200,7 +205,8 @@ ftcrfont_open (struct frame *f, Lisp_Object entity, int pixel_size) block_input (); cairo_glyph_t stack_glyph; - font->min_width = font->average_width = font->space_width = 0; + font->min_width = font->max_width = 0; + font->average_width = font->space_width = 0; for (char c = 32; c < 127; c++) { cairo_glyph_t *glyphs = &stack_glyph; @@ -224,6 +230,8 @@ ftcrfont_open (struct frame *f, Lisp_Object entity, int pixel_size) && (! font->min_width || font->min_width > this_width)) font->min_width = this_width; + if (this_width > font->max_width) + font->max_width = this_width; if (c == 32) font->space_width = this_width; font->average_width += this_width; @@ -278,6 +286,7 @@ ftcrfont_open (struct frame *f, Lisp_Object entity, int pixel_size) font->relative_compose = 0; font->default_ascent = 0; font->vertical_centering = false; + eassert (font->max_width < 512 * 1024 * 1024); return font_object; } @@ -340,14 +349,13 @@ ftcrfont_encode_char (struct font *font, int c) struct font_info *ftcrfont_info = (struct font_info *) font; unsigned code = FONT_INVALID_CODE; unsigned char utf8[MAX_MULTIBYTE_LENGTH]; - unsigned char *p = utf8; + int utf8len = CHAR_STRING (c, utf8); cairo_glyph_t stack_glyph; cairo_glyph_t *glyphs = &stack_glyph; int num_glyphs = 1; - CHAR_STRING_ADVANCE (c, p); if (cairo_scaled_font_text_to_glyphs (ftcrfont_info->cr_scaled_font, 0, 0, - (char *) utf8, p - utf8, + (char *) utf8, utf8len, &glyphs, &num_glyphs, NULL, NULL, NULL) == CAIRO_STATUS_SUCCESS) |