gfx/cairo/quartz-optimize-OVER.patch

   1 From: Robert O'Callahan <robert@ocallahan.org>
   2 Bug 579885. Part 4: Paint opaque surfaces using kPrivateCGCompositeCopy when possible. r=jrmuizel,a=blocking
   3
   4 diff --git a/gfx/cairo/cairo/src/cairo-quartz-surface.c b/gfx/cairo/cairo/src/cairo-quartz-surface.c
   5 --- a/gfx/cairo/cairo/src/cairo-quartz-surface.c
   6 +++ b/gfx/cairo/cairo/src/cairo-quartz-surface.c
   7 @@ -122,16 +122,17 @@ static void (*CGContextClipToMaskPtr) (C
   8  static void (*CGContextDrawTiledImagePtr) (CGContextRef, CGRect, CGImageRef) = NULL;
   9  static unsigned int (*CGContextGetTypePtr) (CGContextRef) = NULL;
  10  static void (*CGContextSetShouldAntialiasFontsPtr) (CGContextRef, bool) = NULL;
  11  static bool (*CGContextGetShouldAntialiasFontsPtr) (CGContextRef) = NULL;
  12  static bool (*CGContextGetShouldSmoothFontsPtr) (CGContextRef) = NULL;
  13  static void (*CGContextSetAllowsFontSmoothingPtr) (CGContextRef, bool) = NULL;
  14  static bool (*CGContextGetAllowsFontSmoothingPtr) (CGContextRef) = NULL;
  15  static void (*CGContextReplacePathWithClipPathPtr) (CGContextRef) = NULL;
  16 +static CGFloat (*CGContextGetAlphaPtr) (CGContextRef) = NULL;
  17
  18  static SInt32 _cairo_quartz_osx_version = 0x0;
  19
  20  static cairo_bool_t _cairo_quartz_symbol_lookup_done = FALSE;
  21
  22  /*
  23   * Utility functions
  24   */
  25 @@ -157,16 +158,17 @@ static void quartz_ensure_symbols(void)
  26      CGContextDrawTiledImagePtr = dlsym(RTLD_DEFAULT, "CGContextDrawTiledImage");
  27      CGContextGetTypePtr = dlsym(RTLD_DEFAULT, "CGContextGetType");
  28      CGContextSetShouldAntialiasFontsPtr = dlsym(RTLD_DEFAULT, "CGContextSetShouldAntialiasFonts");
  29      CGContextGetShouldAntialiasFontsPtr = dlsym(RTLD_DEFAULT, "CGContextGetShouldAntialiasFonts");
  30      CGContextGetShouldSmoothFontsPtr = dlsym(RTLD_DEFAULT, "CGContextGetShouldSmoothFonts");
  31      CGContextReplacePathWithClipPathPtr = dlsym(RTLD_DEFAULT, "CGContextReplacePathWithClipPath");
  32      CGContextGetAllowsFontSmoothingPtr = dlsym(RTLD_DEFAULT, "CGContextGetAllowsFontSmoothing");
  33      CGContextSetAllowsFontSmoothingPtr = dlsym(RTLD_DEFAULT, "CGContextSetAllowsFontSmoothing");
  34 +    CGContextGetAlphaPtr = dlsym(RTLD_DEFAULT, "CGContextGetAlpha");
  35
  36      if (Gestalt(gestaltSystemVersion, &_cairo_quartz_osx_version) != noErr) {
  37         // assume 10.4
  38         _cairo_quartz_osx_version = 0x1040;
  39      }
  40
  41      _cairo_quartz_symbol_lookup_done = TRUE;
  42  }
  43 @@ -1698,16 +1700,28 @@ _cairo_quartz_setup_state (cairo_quartz_
  44
  45      if (source->type == CAIRO_PATTERN_TYPE_RADIAL) {
  46         const cairo_radial_pattern_t *rpat = (const cairo_radial_pattern_t *)source;
  47         _cairo_quartz_setup_radial_source (surface, rpat, extents, &state);
  48         return state;
  49      }
  50
  51      if (source->type == CAIRO_PATTERN_TYPE_SURFACE) {
  52 +        if (op == CAIRO_OPERATOR_OVER && _cairo_pattern_is_opaque (source) &&
  53 +            CGContextGetAlphaPtr &&
  54 +            CGContextGetAlphaPtr (surface->cgContext) == 1.0) {
  55 +            // Quartz won't touch pixels outside the bounds of the
  56 +            // source surface, so we can just go ahead and use Copy here
  57 +            // to accelerate things.
  58 +            // Quartz won't necessarily be able to do this optimization internally;
  59 +            // for CGLayer surfaces, we can know all the pixels are opaque
  60 +            // (because it's CONTENT_COLOR), but Quartz won't know.
  61 +            CGContextSetCompositeOperation (context, kPrivateCGCompositeCopy);
  62 +        }
  63 +
  64         const cairo_surface_pattern_t *spat = (const cairo_surface_pattern_t *) source;
  65          _cairo_quartz_setup_surface_source (surface, spat, extents, &state);
  66          return state;
  67      }
  68
  69      state.action = DO_UNSUPPORTED;
  70      return state;
  71  }