speed-up 4f version of modecolorfilter and modulate

~20% faster

1. Don't call color4f::premul on every invocation
2. Inline modulate as its own special case (used by shadows)

Bug: skia:
Change-Id: I49ca565f589b9a7caac88e95468da7f8c395804a
Reviewed-on: https://skia-review.googlesource.com/15613
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Mike Klein <mtklein@chromium.org>

1 files changed, 19 insertions, 1 deletions

diff --git a/src/core/SkModeColorFilter.cpp b/src/core/SkModeColorFilter.cpp
index 7978f939f5..a5ec5e08ac 100644
--- a/src/core/SkModeColorFilter.cpp
+++ b/src/core/SkModeColorFilter.cpp
@@ -66,7 +66,7 @@ void SkModeColorFilter::filterSpan(const SkPMColor shader[], int count, SkPMColo
 
 void SkModeColorFilter::filterSpan4f(const SkPM4f shader[], int count, SkPM4f result[]) const {
     SkXfermodeProc4f  proc = SkXfermode::GetProc4f(fMode);
-    auto pm4f = SkColor4f::FromColor(fColor).premul();
+    auto pm4f = fPMColor4f;
     for (int i = 0; i < count; i++) {
         result[i] = proc(pm4f, shader[i]);
     }
@@ -80,6 +80,7 @@ void SkModeColorFilter::flatten(SkWriteBuffer& buffer) const {
 void SkModeColorFilter::updateCache() {
     fPMColor = SkPreMultiplyColor(fColor);
     fProc = SkXfermode::GetProc(fMode);
+    fPMColor4f = SkColor4f::FromColor(fColor).premul();
 }
 
 sk_sp<SkFlattenable> SkModeColorFilter::CreateProc(SkReadBuffer& buffer) {
@@ -167,6 +168,21 @@ private:
     typedef SkModeColorFilter INHERITED;
 };
 
+class Modulate_SkModeColorFilter final : public SkModeColorFilter {
+public:
+    Modulate_SkModeColorFilter(SkColor color) : INHERITED(color, SkBlendMode::kModulate) { }
+
+    void filterSpan4f(const SkPM4f shader[], int count, SkPM4f result[]) const override {
+        auto pm4f = fPMColor4f.to4f();
+        for (int i = 0; i < count; i++) {
+            (pm4f * shader[i].to4f()).store(result[i].fVec);
+        }
+    }
+
+private:
+    typedef SkModeColorFilter INHERITED;
+};
+
 ///////////////////////////////////////////////////////////////////////////////
 
 sk_sp<SkColorFilter> SkColorFilter::MakeModeFilter(SkColor color, SkBlendMode mode) {
@@ -207,6 +223,8 @@ sk_sp<SkColorFilter> SkColorFilter::MakeModeFilter(SkColor color, SkBlendMode mo
             return sk_make_sp<Src_SkModeColorFilter>(color);
         case SkBlendMode::kSrcOver:
             return sk_make_sp<SrcOver_SkModeColorFilter>(color);
+        case SkBlendMode::kModulate:
+            return sk_make_sp<Modulate_SkModeColorFilter>(color);
         default:
             return SkModeColorFilter::Make(color, mode);
     }