Copy glyph pixels to font page texture only when there is room left

src/SFML/Graphics/Font.cpp

@@ -573,6 +573,10 @@ Glyph Font::loadGlyph(std::uint32_t codePoint, unsigned int characterSize, bool
  glyph.lsbDelta = static_cast<int>(face->glyph->lsb_delta);
  glyph.rsbDelta = static_cast<int>(face->glyph->rsb_delta);
 
+ // Compute the glyph's bounding box
+ glyph.bounds.position = Vector2f(Vector2i(bitmapGlyph->left, -bitmapGlyph->top));
+ glyph.bounds.size = Vector2f(Vector2u(bitmap.width, bitmap.rows));
+
  Vector2u size(bitmap.width, bitmap.rows);
 
  if ((size.x > 0) && (size.y > 0))
@@ -588,64 +592,64 @@ Glyph Font::loadGlyph(std::uint32_t codePoint, unsigned int characterSize, bool
 
  // Find a good position for the new glyph into the texture
  glyph.textureRect = findGlyphRect(page, size);
+ if (glyph.textureRect.size == Vector2i(size))
+ {
+ // Make sure the texture data is positioned in the center
+ // of the allocated texture rectangle
+ glyph.textureRect.position += Vector2i(padding, padding);
+ glyph.textureRect.size -= 2 * Vector2i(padding, padding);
 
- // Make sure the texture data is positioned in the center
- // of the allocated texture rectangle
- glyph.textureRect.position += Vector2i(padding, padding);
- glyph.textureRect.size -= 2 * Vector2i(padding, padding);
-
- // Compute the glyph's bounding box
- glyph.bounds.position = Vector2f(Vector2i(bitmapGlyph->left, -bitmapGlyph->top));
- glyph.bounds.size = Vector2f(Vector2u(bitmap.width, bitmap.rows));
-
- // Resize the pixel buffer to the new size and fill it with transparent white pixels
- m_pixelBuffer.resize(static_cast<std::size_t>(size.x) * static_cast<std::size_t>(size.y) * 4);
+ // Resize the pixel buffer to the new size and fill it with transparent white pixels
+ m_pixelBuffer.resize(static_cast<std::size_t>(size.x) * static_cast<std::size_t>(size.y) * 4);
 
- std::uint8_t* current = m_pixelBuffer.data();
- std::uint8_t* end = current + size.x * size.y * 4;
+  std::uint8_t* current = m_pixelBuffer.data();
+  std::uint8_t* end = current + size.x * size.y * 4;
 
- while (current != end)
- {
- (*current++) = 255;
- (*current++) = 255;
- (*current++) = 255;
- (*current++) = 0;
- }
+  while (current != end)
+  {
+  (*current++) = 255;
+  (*current++) = 255;
+  (*current++) = 255;
+  (*current++) = 0;
+  }
 
- // Extract the glyph's pixels from the bitmap
- const std::uint8_t* pixels = bitmap.buffer;
- if (bitmap.pixel_mode == FT_PIXEL_MODE_MONO)
- {
- // Pixels are 1 bit monochrome values
- for (unsigned int y = padding; y < size.y - padding; ++y)
+ // Extract the glyph's pixels from the bitmap
+ const std::uint8_t* pixels = bitmap.buffer;
+ if (bitmap.pixel_mode == FT_PIXEL_MODE_MONO)
  {
- for (unsigned int x = padding; x < size.x - padding; ++x)
+ // Pixels are 1 bit monochrome values
+ for (unsigned int y = padding; y < size.y - padding; ++y)
  {
- // The color channels remain white, just fill the alpha channel
- const std::size_t index = x + y * size.x;
- m_pixelBuffer[index * 4 + 3] = ((pixels[(x - padding) / 8]) & (1 << (7 - ((x - padding) % 8)))) ? 255 : 0;
+ for (unsigned int x = padding; x < size.x - padding; ++x)
+ {
+ // The color channels remain white, just fill the alpha channel
+ const std::size_t index = x + y * size.x;
+ m_pixelBuffer[index * 4 + 3] = ((pixels[(x - padding) / 8]) & (1 << (7 - ((x - padding) % 8))))
+ ? 255
+ : 0;
+ }
+ pixels += bitmap.pitch;
  }
- pixels += bitmap.pitch;
  }
- }
- else
- {
- // Pixels are 8 bits gray levels
- for (unsigned int y = padding; y < size.y - padding; ++y)
+ else
  {
- for (unsigned int x = padding; x < size.x - padding; ++x)
+ // Pixels are 8 bits gray levels
+ for (unsigned int y = padding; y < size.y - padding; ++y)
  {
- // The color channels remain white, just fill the alpha channel
- const std::size_t index = x + y * size.x;
- m_pixelBuffer[index * 4 + 3] = pixels[x - padding];
+ for (unsigned int x = padding; x < size.x - padding; ++x)
+ {
+ // The color channels remain white, just fill the alpha channel
+ const std::size_t index = x + y * size.x;
+ m_pixelBuffer[index * 4 + 3] = pixels[x - padding];
+ }
+ pixels += bitmap.pitch;
  }
- pixels += bitmap.pitch;
  }
- }
 
- // Write the pixels to the texture
- const auto dest = Vector2u(glyph.textureRect.position) - Vector2u(padding, padding);
- page.texture.update(m_pixelBuffer.data(), size, dest);
+ // Write the pixels to the texture
+ const auto dest = Vector2u(glyph.textureRect.position) - Vector2u(padding, padding);
+ page.texture.update(m_pixelBuffer.data(), size, dest);
+ }
  }
 
  // Delete the FT glyph
@@ -698,7 +702,7 @@ IntRect Font::findGlyphRect(Page& page, const Vector2u& size) const
  if (!newTexture.create(textureSize * 2u))
  {
  err() << "Failed to create new page texture" << std::endl;
- return {{0, 0}, {2, 2}};
+ return {{0, 0}, {0, 0}};
  }
 
  newTexture.setSmooth(m_isSmooth);
@@ -710,7 +714,7 @@ IntRect Font::findGlyphRect(Page& page, const Vector2u& size) const
  // Oops, we've reached the maximum texture size...
  err() << "Failed to add a new character to the font: the maximum texture size has been reached"
  << std::endl;
- return {{0, 0}, {2, 2}};
+ return {{0, 0}, {0, 0}};
  }
  }