New text::Font::getGlyphAdvance() to get whitespace bounds correctly

aseprite · Aug 26, 2024 · af450af · af450af
1 parent 06279da
commit af450af
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Showing 8 changed files with 24 additions and 3 deletions.
diff --git a/text/empty_font_mgr.cpp b/text/empty_font_mgr.cpp
@@ -39,6 +39,7 @@ class EmptyFont : public Font {
 
   glyph_t codePointToGlyph(codepoint_t) const override { return false; }
   gfx::RectF getGlyphBounds(glyph_t) const override { return gfx::RectF(); }
+  float getGlyphAdvance(glyph_t glyph) const override { return 0; }
 };
 
 class EmptyFontStyleSet : public FontStyleSet {

diff --git a/text/font.h b/text/font.h
@@ -52,6 +52,7 @@ namespace text {
 
     virtual glyph_t codePointToGlyph(codepoint_t cp) const = 0;
     virtual gfx::RectF getGlyphBounds(glyph_t glyph) const = 0;
+    virtual float getGlyphAdvance(glyph_t glyph) const = 0;
 
     Font* fallback() const {
       return m_fallback;

diff --git a/text/freetype_font.cpp b/text/freetype_font.cpp
@@ -119,6 +119,11 @@ gfx::RectF FreeTypeFont::getGlyphBounds(glyph_t glyph) const
   return gfx::RectF();        // TODO impl
 }
 
+float FreeTypeFont::getGlyphAdvance(glyph_t glyph) const
+{
+  return 0;                     // TODO impl
+}
+
 base::Ref<FreeTypeFont> FreeTypeFont::LoadFont(
   ft::Lib& lib,
   const char* filename,

diff --git a/text/freetype_font.h b/text/freetype_font.h
@@ -41,6 +41,7 @@ namespace text {
 
     glyph_t codePointToGlyph(codepoint_t cp) const override;
     gfx::RectF getGlyphBounds(glyph_t glyph) const override;
+    float getGlyphAdvance(glyph_t glyph) const override;
 
     Face& face() { return m_face; }
 

diff --git a/text/skia_font.cpp b/text/skia_font.cpp
@@ -129,4 +129,11 @@ gfx::RectF SkiaFont::getGlyphBounds(glyph_t glyph) const
   return os::from_skia(bounds);
 }
 
+float SkiaFont::getGlyphAdvance(glyph_t glyph) const
+{
+  float widths = 0.0f;
+  m_skFont.getWidthsBounds(&glyph, 1, &widths, nullptr, nullptr);
+  return widths;
+}
+
 } // namespace text
diff --git a/text/skia_font.h b/text/skia_font.h
@@ -35,6 +35,7 @@ namespace text {
 
     glyph_t codePointToGlyph(codepoint_t codepoint) const override;
     gfx::RectF getGlyphBounds(glyph_t glyph) const override;
+    float getGlyphAdvance(glyph_t glyph) const override;
 
     SkFont& skFont() { return m_skFont; }
 

diff --git a/text/sprite_sheet_font.h b/text/sprite_sheet_font.h
@@ -105,6 +105,10 @@ class SpriteSheetFont : public Font {
     return getCharBounds(128);
   }
 
+  float getGlyphAdvance(glyph_t glyph) const override {
+    return getGlyphBounds(glyph).w;
+  }
+
   gfx::RectF getGlyphBoundsOnSheet(glyph_t glyph) const {
     if (glyph >= 0 && glyph < (int)m_glyphs.size())
       return m_glyphs[glyph];

diff --git a/text/text_blob.cpp b/text/text_blob.cpp
@@ -68,9 +68,10 @@ gfx::RectF TextBlob::RunInfo::getGlyphBounds(const size_t i) const
 
   // Get bounds of whitespace from a space glyph.
   if (bounds.isEmpty()) {
-    auto glyph = font->getGlyphBounds(' ');
-    bounds.w = glyph.w - glyph.x;
-    bounds.h = glyph.h - glyph.y;
+    FontMetrics metrics;
+    font->metrics(&metrics);
+    bounds.w = font->getGlyphAdvance(font->codePointToGlyph(' '));
+    bounds.h = std::abs(metrics.capHeight);
   }
 
   ASSERT(!bounds.isEmpty());