consolidate logic for matrix stage

Bug: skia:
Change-Id: Id1559b31692a1aed9aa4d15620b2019ae9c7c22b
Reviewed-on: https://skia-review.googlesource.com/21404
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Florin Malita <fmalita@chromium.org>

5 files changed, 19 insertions, 21 deletions

diff --git a/src/core/SkRasterPipeline.cpp b/src/core/SkRasterPipeline.cpp
index 45d081bec5..6f5ae8c435 100644
--- a/src/core/SkRasterPipeline.cpp
+++ b/src/core/SkRasterPipeline.cpp
@@ -82,3 +82,14 @@ void SkRasterPipeline::append_from_srgb_dst(SkAlphaType at) {
         this->append(SkRasterPipeline::clamp_a_dst);
     }
 }
+
+void SkRasterPipeline::append_matrix(SkArenaAlloc* alloc, const SkMatrix& matrix) {
+    float* storage = alloc->makeArray<float>(9);
+    // TODO: consider adding special stages for scale+translate and possibly just translate.
+    if (matrix.asAffine(storage)) {
+        this->append(SkRasterPipeline::matrix_2x3, storage);
+    } else {
+        matrix.get9(storage);
+        this->append(SkRasterPipeline::matrix_perspective, storage);
+    }
+}
diff --git a/src/core/SkRasterPipeline.h b/src/core/SkRasterPipeline.h
index a4175c65a8..9a467a5024 100644
--- a/src/core/SkRasterPipeline.h
+++ b/src/core/SkRasterPipeline.h
@@ -127,6 +127,10 @@ public:
     void append_from_srgb(SkAlphaType);
     void append_from_srgb_dst(SkAlphaType);
 
+    // Appends a stage for the specified matrix. Tries to optimize the stage by analyzing
+    // the type of matrix.
+    void append_matrix(SkArenaAlloc*, const SkMatrix&);
+
     bool empty() const { return fStages == nullptr; }
 
 private:
diff --git a/src/shaders/SkImageShader.cpp b/src/shaders/SkImageShader.cpp
index 9538232cf0..064fe7b975 100644
--- a/src/shaders/SkImageShader.cpp
+++ b/src/shaders/SkImageShader.cpp
@@ -295,17 +295,11 @@ bool SkImageShader::onAppendStages(SkRasterPipeline* p, SkColorSpace* dstCS, SkA
     struct MiscCtx {
         std::unique_ptr<SkBitmapController::State> state;
         SkColor4f paint_color;
-        float     matrix[9];
     };
     auto misc = alloc->make<MiscCtx>();
     misc->state       = std::move(state);  // Extend lifetime to match the pipeline's.
     misc->paint_color = SkColor4f_from_SkColor(paint.getColor(), dstCS);
-    if (matrix.asAffine(misc->matrix)) {
-        p->append(SkRasterPipeline::matrix_2x3, misc->matrix);
-    } else {
-        matrix.get9(misc->matrix);
-        p->append(SkRasterPipeline::matrix_perspective, misc->matrix);
-    }
+    p->append_matrix(alloc, matrix);
 
     auto gather = alloc->make<SkJumper_GatherCtx>();
     gather->pixels  = pm.addr();
diff --git a/src/shaders/gradients/SkGradientShader.cpp b/src/shaders/gradients/SkGradientShader.cpp
index 40da6940fe..6e952ae17f 100644
--- a/src/shaders/gradients/SkGradientShader.cpp
+++ b/src/shaders/gradients/SkGradientShader.cpp
@@ -382,15 +382,7 @@ bool SkGradientShaderBase::onAppendStages(SkRasterPipeline* p,
     }
 
     p->append(SkRasterPipeline::seed_shader);
-
-    auto* m = alloc->makeArrayDefault<float>(9);
-    if (matrix.asAffine(m)) {
-        p->append(SkRasterPipeline::matrix_2x3, m);
-    } else {
-        matrix.get9(m);
-        p->append(SkRasterPipeline::matrix_perspective, m);
-    }
-
+    p->append_matrix(alloc, matrix);
     p->extend(tPipeline);
 
     switch(fTileMode) {
diff --git a/src/shaders/gradients/SkTwoPointConicalGradient.cpp b/src/shaders/gradients/SkTwoPointConicalGradient.cpp
index f79e78c310..f355971e43 100644
--- a/src/shaders/gradients/SkTwoPointConicalGradient.cpp
+++ b/src/shaders/gradients/SkTwoPointConicalGradient.cpp
@@ -190,11 +190,8 @@ bool SkTwoPointConicalGradient::adjustMatrixAndAppendStages(SkArenaAlloc* alloc,
         auto scale =  fRadius2 / dRadius;
         auto bias  = -fRadius1 / dRadius;
 
-        auto mad_matrix = SkMatrix::Concat(SkMatrix::MakeTrans(bias, 0),
-                                           SkMatrix::MakeScale(scale, 1));
-        auto m = alloc->makeArrayDefault<float>(6);
-        SkAssertResult(mad_matrix.asAffine(m));
-        p->append(SkRasterPipeline::matrix_2x3, m);
+        p->append_matrix(alloc, SkMatrix::Concat(SkMatrix::MakeTrans(bias, 0),
+                                                 SkMatrix::MakeScale(scale, 1)));
 
         return true;
     }