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| author |  commit-bot@chromium.org <commit-bot@chromium.org@2bbb7eff-a529-9590-31e7-b0007b416f81> | 2013-07-15 12:20:36 +0000 |
|---|---|---|
| committer | commit-bot@chromium.org <commit-bot@chromium.org@2bbb7eff-a529-9590-31e7-b0007b416f81> | 2013-07-15 12:20:36 +0000 |
| commit | e38e53b5327e2618a97fb26a697a477b74c44d3d (patch) | |
| tree | 32fc5f26d20195b701c8f1010c771d084ba82ceb | |
| parent | afbb685123a12886aab028c3b1378d09874a8ee9 (diff) | |
ARM Skia NEON patches - 07 - Equation simplification
Misc: simplify the equation of the exclusion Xfermode
The equation can be dramatically simplified. The results with gm are
the same except that the code is faster.
BUG=
R=djsollen@google.com, reed@google.com, bsalomon@google.com, cabanier@adobe.com
Author: kevin.petit.arm@gmail.com
Review URL: https://chromiumcodereview.appspot.com/18112016
git-svn-id: http://skia.googlecode.com/svn/trunk@10069 2bbb7eff-a529-9590-31e7-b0007b416f81
| -rw-r--r-- | src/core/SkXfermode.cpp | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/src/core/SkXfermode.cpp b/src/core/SkXfermode.cpp index 2cfdcfa4b3..020ea48b37 100644 --- a/src/core/SkXfermode.cpp +++ b/src/core/SkXfermode.cpp @@ -400,9 +400,12 @@ static SkPMColor difference_modeproc(SkPMColor src, SkPMColor dst) { } // kExclusion_Mode -static inline int exclusion_byte(int sc, int dc, int sa, int da) { +static inline int exclusion_byte(int sc, int dc, int, int) { // this equations is wacky, wait for SVG to confirm it - int r = sc * da + dc * sa - 2 * sc * dc + sc * (255 - da) + dc * (255 - sa); + //int r = sc * da + dc * sa - 2 * sc * dc + sc * (255 - da) + dc * (255 - sa); + + // The above equation can be simplified as follows + int r = 255*(sc + dc) - 2 * sc * dc; return clamp_div255round(r); } static SkPMColor exclusion_modeproc(SkPMColor src, SkPMColor dst) { |