make SkColorFilter::onAppendStages() pure

Change-Id: I2851e19648fb0478db9b940e86c6ddb2020000b3
Reviewed-on: https://skia-review.googlesource.com/18264
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Mike Reed <reed@google.com>

5 files changed, 29 insertions, 32 deletions

diff --git a/include/core/SkColorFilter.h b/include/core/SkColorFilter.h
index 1c320ba30f..75401627fd 100644
--- a/include/core/SkColorFilter.h
+++ b/include/core/SkColorFilter.h
@@ -184,12 +184,7 @@ private:
     }
 
     virtual void onAppendStages(SkRasterPipeline*, SkColorSpace*, SkArenaAlloc*,
-                                bool shaderIsOpaque) const;
-
-
-    virtual void onFilterStage(const SkPM4f[], int, SkPM4f[]) const {
-        SkASSERT(false);
-    }
+                                bool shaderIsOpaque) const = 0;
 
     friend class SkColorSpaceXformer;
     friend class SkComposeColorFilter;
diff --git a/src/core/SkColorFilter.cpp b/src/core/SkColorFilter.cpp
index 9304c7c803..65b5c45308 100644
--- a/src/core/SkColorFilter.cpp
+++ b/src/core/SkColorFilter.cpp
@@ -48,24 +48,6 @@ void SkColorFilter::appendStages(SkRasterPipeline* p,
     this->onAppendStages(p, dstCS, alloc, shaderIsOpaque);
 }
 
-void SkColorFilter::onAppendStages(SkRasterPipeline* p,
-                                   SkColorSpace* dstCS,
-                                   SkArenaAlloc* alloc,
-                                   bool) const {
-    struct Ctx : SkJumper_CallbackCtx {
-        sk_sp<SkColorFilter> cf;
-    };
-    auto ctx = alloc->make<Ctx>();
-    ctx->cf = dstCS ? SkColorSpaceXformer::Make(sk_ref_sp(dstCS))->apply(this)
-                    : sk_ref_sp(const_cast<SkColorFilter*>(this));
-    ctx->fn = [](SkJumper_CallbackCtx* arg, int active_pixels) {
-        auto ctx = (Ctx*)arg;
-        auto buf = (SkPM4f*)ctx->rgba;
-        ctx->cf->onFilterStage(buf, active_pixels, buf);
-    };
-    p->append(SkRasterPipeline::callback, ctx);
-}
-
 SkColor SkColorFilter::filterColor(SkColor c) const {
     SkPMColor dst, src = SkPreMultiplyColor(c);
     this->filterSpan(&src, 1, &dst);
diff --git a/src/effects/SkOverdrawColorFilter.cpp b/src/effects/SkOverdrawColorFilter.cpp
index bbeb028144..a4e13f9935 100644
--- a/src/effects/SkOverdrawColorFilter.cpp
+++ b/src/effects/SkOverdrawColorFilter.cpp
@@ -5,9 +5,12 @@
  * found in the LICENSE file.
  */
 
+#include "SkArenaAlloc.h"
 #include "SkOverdrawColorFilter.h"
 #include "SkPM4f.h"
+#include "SkRasterPipeline.h"
 #include "SkReadBuffer.h"
+#include "../jumper/SkJumper.h"
 
 void SkOverdrawColorFilter::filterSpan(const SkPMColor src[], int count, SkPMColor dst[]) const {
     for (int x = 0; x < count; x++) {
@@ -20,14 +23,28 @@ void SkOverdrawColorFilter::filterSpan(const SkPMColor src[], int count, SkPMCol
     }
 }
 
-void SkOverdrawColorFilter::onFilterStage(const SkPM4f src[], int count, SkPM4f dst[]) const {
-    for (int i = 0; i < count; ++i) {
-        uint8_t alpha = (int)(src[i].a() * 255);
-        if (alpha >= kNumColors) {
-            alpha = kNumColors - 1;
+void SkOverdrawColorFilter::onAppendStages(SkRasterPipeline* p,
+                                           SkColorSpace* dstCS,
+                                           SkArenaAlloc* alloc,
+                                           bool shader_is_opaque) const {
+    struct Ctx : public SkJumper_CallbackCtx {
+        const SkPMColor* colors;
+    };
+    // TODO: do we care about transforming to dstCS?
+    auto ctx = alloc->make<Ctx>();
+    ctx->colors = fColors;
+    ctx->fn = [](SkJumper_CallbackCtx* arg, int active_pixels) {
+        auto ctx = (Ctx*)arg;
+        auto pixels = (SkPM4f*)ctx->rgba;
+        for (int i = 0; i < active_pixels; i++) {
+            uint8_t alpha = (int)(pixels[i].a() * 255);
+            if (alpha >= kNumColors) {
+                alpha = kNumColors - 1;
+            }
+            pixels[i] = SkPM4f::FromPMColor(ctx->colors[alpha]);
         }
-        dst[i] = SkPM4f::FromPMColor(fColors[alpha]);
-    }
+    };
+    p->append(SkRasterPipeline::callback, ctx);
 }
 
 void SkOverdrawColorFilter::toString(SkString* str) const {
diff --git a/src/effects/SkOverdrawColorFilter.h b/src/effects/SkOverdrawColorFilter.h
index 09c5173bf6..41d7988577 100644
--- a/src/effects/SkOverdrawColorFilter.h
+++ b/src/effects/SkOverdrawColorFilter.h
@@ -46,7 +46,7 @@ private:
         memcpy(fColors, colors, kNumColors * sizeof(SkPMColor));
     }
 
-    void onFilterStage(const SkPM4f src[], int count, SkPM4f result[]) const override;
+    void onAppendStages(SkRasterPipeline*, SkColorSpace*, SkArenaAlloc*, bool) const override;
 
     SkPMColor fColors[kNumColors];
 
diff --git a/tools/sk_tool_utils.cpp b/tools/sk_tool_utils.cpp
index 95f4cb1a6e..c792c48475 100644
--- a/tools/sk_tool_utils.cpp
+++ b/tools/sk_tool_utils.cpp
@@ -40,6 +40,9 @@ public:
     void filterSpan(const SkPMColor src[], int count, SkPMColor dst[]) const override {
         SK_ABORT("SkSRGBColorFilter is only implemented for GPU");
     }
+    void onAppendStages(SkRasterPipeline*, SkColorSpace*, SkArenaAlloc*, bool) const override {
+        SK_ABORT("SkSRGBColorFilter is only implemented for GPU");
+    }
     Factory getFactory() const override { return nullptr; }
 
 #ifndef SK_IGNORE_TO_STRING