SkColorSpaceXformer: Add SkShader::makeColorSpace()

Just a refactor - reimplements the shader xforms with makeColorSpace().

11 gms have diffs.  Some are down to floating precision.  The old
implementation would go float->fixed->float in some cases.  Others
are due to improvements with gradient shaders inside local matrix
shaders.

Bug: skia:6516
Change-Id: I424406990c5c58a47833cf4c9ef146cd3ea6c37e
Reviewed-on: https://skia-review.googlesource.com/13769
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Matt Sarett <msarett@google.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/include/core/SkShader.h b/include/core/SkShader.h
index e49ad5f6a6..b3b5faaa1f 100644
--- a/include/core/SkShader.h
+++ b/include/core/SkShader.h
@@ -20,6 +20,7 @@
 class SkArenaAlloc;
 class SkColorFilter;
 class SkColorSpace;
+class SkColorSpaceXformer;
 class SkImage;
 class SkPath;
 class SkPicture;
@@ -497,6 +498,16 @@ protected:
                                 const SkMatrix&, const SkPaint&,
                                 const SkMatrix* /*local matrix*/) const;
 
+    /**
+     *  Returns a shader transformed into a new color space via the |xformer|.
+     */
+    sk_sp<SkShader> makeColorSpace(SkColorSpaceXformer* xformer) const {
+        return this->onMakeColorSpace(xformer);
+    }
+    virtual sk_sp<SkShader> onMakeColorSpace(SkColorSpaceXformer*) const {
+        return sk_ref_sp(const_cast<SkShader*>(this));
+    }
+
 private:
     // This is essentially const, but not officially so it can be modified in
     // constructors.
@@ -505,6 +516,8 @@ private:
     // So the SkLocalMatrixShader can whack fLocalMatrix in its SkReadBuffer constructor.
     friend class SkLocalMatrixShader;
     friend class SkBitmapProcLegacyShader;    // for computeTotalInverse()
+    friend class SkComposeShader;
+    friend class SkColorSpaceXformer;
 
     typedef SkFlattenable INHERITED;
 };