Bug 1616587 - Implement conic-gradient for Skia graphics backend. r=lsalzman

Differential Revision: https://phabricator.services.mozilla.com/D63415

--HG--
extra : moz-landing-system : lando

gfx/2d/2D.h

@@ -290,6 +290,29 @@ class RadialGradientPattern : public Pattern {
   Matrix mMatrix;  //!< A matrix that transforms the pattern into user space
 };
 
+/**
+ * This class is used for Conic Gradient Patterns, the gradient stops are
+ * stored in a separate object and are backend dependent. This class itself
+ * may be used on the stack.
+ */
+class ConicGradientPattern : public Pattern {
+ public:
+  /// For constructor parameter description, see member data documentation.
+  ConicGradientPattern(const Point& aCenter, Float aAngle,
+                       GradientStops* aStops, const Matrix& aMatrix = Matrix())
+      : mCenter(aCenter), mAngle(aAngle), mStops(aStops), mMatrix(aMatrix) {}
+
+  PatternType GetType() const override { return PatternType::CONIC_GRADIENT; }
+
+  Point mCenter;  //!< Center of the gradient
+  Float mAngle;   //!< Start angle of gradient
+  RefPtr<GradientStops>
+      mStops;      /**< GradientStops object for this gradient, this
+                        should match the backend type of the draw target
+                        this pattern will be used with. */
+  Matrix mMatrix;  //!< A matrix that transforms the pattern into user space
+};
+
 /**
  * This class is used for Surface Patterns, they wrap a surface and a
  * repetition mode for the surface. This may be used on the stack.

gfx/2d/DrawCommands.h

@@ -68,6 +68,10 @@ class StoredPattern {
         new (mRadial) RadialGradientPattern(
             *static_cast<const RadialGradientPattern*>(&aPattern));
         return;
+      case PatternType::CONIC_GRADIENT:
+        new (mConic) ConicGradientPattern(
+            *static_cast<const ConicGradientPattern*>(&aPattern));
+        return;
     }
   }
 
@@ -98,6 +102,7 @@ class StoredPattern {
     char mColor[sizeof(ColorPattern)];
     char mLinear[sizeof(LinearGradientPattern)];
     char mRadial[sizeof(RadialGradientPattern)];
+    char mConic[sizeof(ConicGradientPattern)];
     char mSurface[sizeof(SurfacePattern)];
   };
 };

gfx/2d/DrawTargetSkia.cpp

@@ -494,6 +494,42 @@ static void SetPaintPattern(SkPaint& aPaint, const Pattern& aPattern,
       }
       break;
     }
+    case PatternType::CONIC_GRADIENT: {
+      const ConicGradientPattern& pat =
+          static_cast<const ConicGradientPattern&>(aPattern);
+      GradientStopsSkia* stops =
+          static_cast<GradientStopsSkia*>(pat.mStops.get());
+      if (!stops || stops->mCount < 2 || !pat.mCenter.IsFinite() ||
+          !IsFinite(pat.mAngle)) {
+        aPaint.setColor(SK_ColorTRANSPARENT);
+      } else {
+        SkMatrix mat;
+        GfxMatrixToSkiaMatrix(pat.mMatrix, mat);
+        if (aMatrix) {
+          mat.postConcat(*aMatrix);
+        }
+
+        SkScalar cx = SkFloatToScalar(pat.mCenter.x);
+        SkScalar cy = SkFloatToScalar(pat.mCenter.y);
+
+        // Skia's sweep gradient angles are relative to the x-axis, not the
+        // y-axis.
+        Float angle = (pat.mAngle * 180.0 / M_PI) - 90.0;
+        if (angle != 0.0) {
+          mat.preRotate(angle, cx, cy);
+        }
+
+        sk_sp<SkShader> shader = SkGradientShader::MakeSweep(
+            cx, cy, &stops->mColors.front(), &stops->mPositions.front(),
+            stops->mCount, 0, &mat);
+        if (shader) {
+          aPaint.setShader(shader);
+        } else {
+          aPaint.setColor(SK_ColorTRANSPARENT);
+        }
+      }
+      break;
+    }
     case PatternType::SURFACE: {
       const SurfacePattern& pat = static_cast<const SurfacePattern&>(aPattern);
       sk_sp<SkImage> image =

gfx/2d/PatternHelpers.h

@@ -52,6 +52,10 @@ class GeneralPattern final {
         mPattern = new (mRadialGradientPattern.addr()) RadialGradientPattern(
             static_cast<const RadialGradientPattern&>(aPattern));
         break;
+      case PatternType::CONIC_GRADIENT:
+        mPattern = new (mConicGradientPattern.addr()) ConicGradientPattern(
+            static_cast<const ConicGradientPattern&>(aPattern));
+        break;
       case PatternType::SURFACE:
         mPattern = new (mSurfacePattern.addr())
             SurfacePattern(static_cast<const SurfacePattern&>(aPattern));
@@ -86,6 +90,15 @@ class GeneralPattern final {
     return mRadialGradientPattern.addr();
   }
 
+  ConicGradientPattern* InitConicGradientPattern(
+      const Point& aCenter, Float aAngle, GradientStops* aStops,
+      const Matrix& aMatrix = Matrix()) {
+    MOZ_ASSERT(!mPattern);
+    mPattern = new (mConicGradientPattern.addr())
+        ConicGradientPattern(aCenter, aAngle, aStops, aMatrix);
+    return mConicGradientPattern.addr();
+  }
+
   SurfacePattern* InitSurfacePattern(
       SourceSurface* aSourceSurface, ExtendMode aExtendMode,
       const Matrix& aMatrix = Matrix(),
@@ -113,6 +126,7 @@ class GeneralPattern final {
     AlignedStorage2<ColorPattern> mColorPattern;
     AlignedStorage2<LinearGradientPattern> mLinearGradientPattern;
     AlignedStorage2<RadialGradientPattern> mRadialGradientPattern;
+    AlignedStorage2<ConicGradientPattern> mConicGradientPattern;
     AlignedStorage2<SurfacePattern> mSurfacePattern;
   };
   Pattern* mPattern = nullptr;

gfx/2d/RecordedEvent.h

@@ -129,6 +129,13 @@ struct RadialGradientPatternStorage {
   Matrix mMatrix;
 };
 
+struct ConicGradientPatternStorage {
+  Point mCenter;
+  Float mAngle;
+  ReferencePtr mStops;
+  Matrix mMatrix;
+};
+
 struct SurfacePatternStorage {
   ExtendMode mExtend;
   SamplingFilter mSamplingFilter;
@@ -144,6 +151,7 @@ struct PatternStorage {
     char mColor[sizeof(ColorPatternStorage)];
     char mLinear[sizeof(LinearGradientPatternStorage)];
     char mRadial[sizeof(RadialGradientPatternStorage)];
+    char mConic[sizeof(ConicGradientPatternStorage)];
     char mSurface[sizeof(SurfacePatternStorage)];
   };
 };

gfx/2d/RecordedEventImpl.h

@@ -1564,6 +1564,12 @@ void RecordedEvent::RecordPatternData(S& aStream,
                        &aPattern.mStorage));
       return;
     }
+    case PatternType::CONIC_GRADIENT: {
+      WriteElement(aStream,
+                   *reinterpret_cast<const ConicGradientPatternStorage*>(
+                       &aPattern.mStorage));
+      return;
+    }
     case PatternType::SURFACE: {
       WriteElement(aStream, *reinterpret_cast<const SurfacePatternStorage*>(
                                 &aPattern.mStorage));
@@ -1596,6 +1602,11 @@ void RecordedEvent::ReadPatternData(S& aStream,
                                &aPattern.mStorage));
       return;
     }
+    case PatternType::CONIC_GRADIENT: {
+      ReadElement(aStream, *reinterpret_cast<ConicGradientPatternStorage*>(
+                               &aPattern.mStorage));
+      return;
+    }
     case PatternType::SURFACE: {
       SurfacePatternStorage* sps =
           reinterpret_cast<SurfacePatternStorage*>(&aPattern.mStorage);
@@ -1661,6 +1672,18 @@ inline void RecordedEvent::StorePattern(PatternStorage& aDestination,
       store->mStops = pat->mStops.get();
       return;
     }
+    case PatternType::CONIC_GRADIENT: {
+      ConicGradientPatternStorage* store =
+          reinterpret_cast<ConicGradientPatternStorage*>(
+              &aDestination.mStorage);
+      const ConicGradientPattern* pat =
+          static_cast<const ConicGradientPattern*>(&aSource);
+      store->mCenter = pat->mCenter;
+      store->mAngle = pat->mAngle;
+      store->mMatrix = pat->mMatrix;
+      store->mStops = pat->mStops.get();
+      return;
+    }
     case PatternType::SURFACE: {
       SurfacePatternStorage* store =
           reinterpret_cast<SurfacePatternStorage*>(&aDestination.mStorage);
@@ -1804,6 +1827,14 @@ inline void RecordedEvent::OutputSimplePatternInfo(
               << store->mCenter2.y << ") Radius 2: " << store->mRadius2;
       return;
     }
+    case PatternType::CONIC_GRADIENT: {
+      const ConicGradientPatternStorage* store =
+          reinterpret_cast<const ConicGradientPatternStorage*>(
+              &aStorage.mStorage);
+      aOutput << "ConicGradient (Center: (" << store->mCenter.x << ", "
+              << store->mCenter.y << ") Angle: " << store->mAngle;
+      return;
+    }
     case PatternType::SURFACE: {
       const SurfacePatternStorage* store =
           reinterpret_cast<const SurfacePatternStorage*>(&aStorage.mStorage);
@@ -2139,6 +2170,16 @@ struct GenericPattern {
             storage->mMatrix);
         return mPattern;
       }
+      case PatternType::CONIC_GRADIENT: {
+        ConicGradientPatternStorage* storage =
+            reinterpret_cast<ConicGradientPatternStorage*>(&mStorage->mStorage);
+        mPattern = new (mConGradPat) ConicGradientPattern(
+            storage->mCenter, storage->mAngle,
+            storage->mStops ? mTranslator->LookupGradientStops(storage->mStops)
+                            : nullptr,
+            storage->mMatrix);
+        return mPattern;
+      }
       default:
         return new (mColPat) ColorPattern(Color());
     }
@@ -2150,6 +2191,7 @@ struct GenericPattern {
     char mColPat[sizeof(ColorPattern)];
     char mLinGradPat[sizeof(LinearGradientPattern)];
     char mRadGradPat[sizeof(RadialGradientPattern)];
+    char mConGradPat[sizeof(ConicGradientPattern)];
     char mSurfPat[sizeof(SurfacePattern)];
   };
 

gfx/2d/Types.h

@@ -414,7 +414,8 @@ enum class PatternType : int8_t {
   COLOR,
   SURFACE,
   LINEAR_GRADIENT,
-  RADIAL_GRADIENT
+  RADIAL_GRADIENT,
+  CONIC_GRADIENT
 };
 
 enum class JoinStyle : int8_t {

gfx/thebes/gfxPattern.cpp

@@ -37,6 +37,12 @@ gfxPattern::gfxPattern(gfxFloat cx0, gfxFloat cy0, gfxFloat radius0,
                                         radius0, radius1, nullptr);
 }
 
+// conic
+gfxPattern::gfxPattern(gfxFloat cx, gfxFloat cy, gfxFloat angle)
+    : mExtend(ExtendMode::CLAMP) {
+  mGfxPattern.InitConicGradientPattern(Point(cx, cy), angle, nullptr);
+}
+
 // Azure
 gfxPattern::gfxPattern(SourceSurface* aSurface,
                        const Matrix& aPatternToUserSpace)
@@ -48,7 +54,8 @@ gfxPattern::gfxPattern(SourceSurface* aSurface,
 
 void gfxPattern::AddColorStop(gfxFloat offset, const Color& c) {
   if (mGfxPattern.GetPattern()->GetType() != PatternType::LINEAR_GRADIENT &&
-      mGfxPattern.GetPattern()->GetType() != PatternType::RADIAL_GRADIENT) {
+      mGfxPattern.GetPattern()->GetType() != PatternType::RADIAL_GRADIENT &&
+      mGfxPattern.GetPattern()->GetType() != PatternType::CONIC_GRADIENT) {
     return;
   }
 
@@ -136,6 +143,13 @@ Pattern* gfxPattern::GetPattern(const DrawTarget* aTarget,
       radialGradientPattern->mStops = mStops;
       break;
     }
+    case PatternType::CONIC_GRADIENT: {
+      ConicGradientPattern* conicGradientPattern =
+          static_cast<ConicGradientPattern*>(mGfxPattern.GetPattern());
+      conicGradientPattern->mMatrix = patternToUser;
+      conicGradientPattern->mStops = mStops;
+      break;
+    }
     default:
       /* Reassure the compiler we are handling all the enum values.  */
       break;

gfx/thebes/gfxPattern.h

@@ -22,10 +22,11 @@ class gfxPattern final {
 
  public:
   explicit gfxPattern(const mozilla::gfx::Color& aColor);
-  // linear
+  // gradients
   gfxPattern(gfxFloat x0, gfxFloat y0, gfxFloat x1, gfxFloat y1);  // linear
   gfxPattern(gfxFloat cx0, gfxFloat cy0, gfxFloat radius0, gfxFloat cx1,
-             gfxFloat cy1, gfxFloat radius1);  // radial
+             gfxFloat cy1, gfxFloat radius1);            // radial
+  gfxPattern(gfxFloat cx, gfxFloat cy, gfxFloat angle);  // conic
   gfxPattern(mozilla::gfx::SourceSurface* aSurface,
              const mozilla::gfx::Matrix& aPatternToUserSpace);
 

layout/painting/nsCSSRenderingGradients.cpp

@@ -951,8 +951,7 @@ void nsCSSGradientRenderer::Paint(gfxContext& aContext, const nsRect& aDest,
       matrix.PreTranslate(-mLineStart);
     }
   } else {
-    // conic-gradient is only implemented for WebRender
-    return;
+    gradientPattern = new gfxPattern(mCenter.x, mCenter.y, mAngle);
   }
   // Use a pattern transform to take account of source and dest rects
   matrix.PreTranslate(gfxPoint(mPresContext->CSSPixelsToDevPixels(aSrc.x),
@@ -962,7 +961,7 @@ void nsCSSGradientRenderer::Paint(gfxContext& aContext, const nsRect& aDest,
       gfxFloat(nsPresContext::CSSPixelsToAppUnits(aSrc.height)) / aDest.height);
   gradientPattern->SetMatrix(matrix);
 
-  if (stopDelta == 0.0) {
+  if (!mGradient->IsConic() && stopDelta == 0.0) {
     // Non-repeating gradient with all stops in same place -> just add
     // first stop and last stop, both at position 0.
     // Repeating gradient with all stops in the same place, or radial