Add shadowrrect geometry processor

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=4233

Change-Id: I637099709cfe30f7d3c1883e23840a47a7a25c10
Reviewed-on: https://skia-review.googlesource.com/4233
Commit-Queue: Jim Van Verth <jvanverth@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>

1 files changed, 964 insertions, 0 deletions

diff --git a/src/gpu/batches/GrShadowRRectBatch.cpp b/src/gpu/batches/GrShadowRRectBatch.cpp
new file mode 100755
index 0000000000..08f7e86952
--- /dev/null
+++ b/src/gpu/batches/GrShadowRRectBatch.cpp
@@ -0,0 +1,964 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "GrShadowRRectBatch.h"
+
+#include "GrBatchFlushState.h"
+#include "GrBatchTest.h"
+#include "GrResourceProvider.h"
+#include "GrStyle.h"
+
+#include "effects/GrShadowGeoProc.h"
+
+///////////////////////////////////////////////////////////////////////////////
+
+// We have two possible cases for geometry for a circle:
+
+// In the case of a normal fill, we draw geometry for the circle as an octagon.
+static const uint16_t gFillCircleIndices[] = {
+    // enter the octagon
+    0, 1, 8, 1, 2, 8,
+    2, 3, 8, 3, 4, 8,
+    4, 5, 8, 5, 6, 8,
+    6, 7, 8, 7, 0, 8,
+};
+
+// For stroked circles, we use two nested octagons.
+static const uint16_t gStrokeCircleIndices[] = {
+    // enter the octagon
+    0, 1, 9, 0, 9, 8,
+    1, 2, 10, 1, 10, 9,
+    2, 3, 11, 2, 11, 10,
+    3, 4, 12, 3, 12, 11,
+    4, 5, 13, 4, 13, 12,
+    5, 6, 14, 5, 14, 13,
+    6, 7, 15, 6, 15, 14,
+    7, 0, 8, 7, 8, 15,
+};
+
+static const int kIndicesPerFillCircle = SK_ARRAY_COUNT(gFillCircleIndices);
+static const int kIndicesPerStrokeCircle = SK_ARRAY_COUNT(gStrokeCircleIndices);
+static const int kVertsPerStrokeCircle = 16;
+static const int kVertsPerFillCircle = 9;
+
+static int circle_type_to_vert_count(bool stroked) {
+    return stroked ? kVertsPerStrokeCircle : kVertsPerFillCircle;
+}
+
+static int circle_type_to_index_count(bool stroked) {
+    return stroked ? kIndicesPerStrokeCircle : kIndicesPerFillCircle;
+}
+
+static const uint16_t* circle_type_to_indices(bool stroked) {
+    return stroked ? gStrokeCircleIndices : gFillCircleIndices;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+class ShadowCircleBatch : public GrVertexBatch {
+public:
+    DEFINE_BATCH_CLASS_ID
+
+    static GrDrawBatch* Create(GrColor color, const SkMatrix& viewMatrix, SkPoint center,
+                               SkScalar radius, SkScalar blurRadius, const GrStyle& style) {
+        SkASSERT(viewMatrix.isSimilarity());
+        const SkStrokeRec& stroke = style.strokeRec();
+        if (style.hasPathEffect()) {
+            return nullptr;
+        }
+        SkStrokeRec::Style recStyle = stroke.getStyle();
+
+        viewMatrix.mapPoints(&center, 1);
+        radius = viewMatrix.mapRadius(radius);
+        SkScalar strokeWidth = viewMatrix.mapRadius(stroke.getWidth());
+
+        bool isStrokeOnly = SkStrokeRec::kStroke_Style == recStyle ||
+                            SkStrokeRec::kHairline_Style == recStyle;
+        bool hasStroke = isStrokeOnly || SkStrokeRec::kStrokeAndFill_Style == recStyle;
+
+        SkScalar innerRadius = -SK_ScalarHalf;
+        SkScalar outerRadius = radius;
+        SkScalar halfWidth = 0;
+        if (hasStroke) {
+            if (SkScalarNearlyZero(strokeWidth)) {
+                halfWidth = SK_ScalarHalf;
+            } else {
+                halfWidth = SkScalarHalf(strokeWidth);
+            }
+
+            outerRadius += halfWidth;
+            if (isStrokeOnly) {
+                innerRadius = radius - halfWidth;
+            }
+        }
+
+        // TODO: still needed?
+        // The radii are outset for two reasons. First, it allows the shader to simply perform
+        // simpler computation because the computed alpha is zero, rather than 50%, at the radius.
+        // Second, the outer radius is used to compute the verts of the bounding box that is
+        // rendered and the outset ensures the box will cover all partially covered by the circle.
+        outerRadius += SK_ScalarHalf;
+        innerRadius -= SK_ScalarHalf;
+        bool stroked = isStrokeOnly && innerRadius > 0.0f;
+        ShadowCircleBatch* batch = new ShadowCircleBatch();
+        batch->fViewMatrixIfUsingLocalCoords = viewMatrix;
+
+        SkRect devBounds = SkRect::MakeLTRB(center.fX - outerRadius, center.fY - outerRadius,
+                                            center.fX + outerRadius, center.fY + outerRadius);
+
+        batch->fGeoData.emplace_back(Geometry{
+            color,
+            outerRadius,
+            innerRadius,
+            blurRadius,
+            devBounds,
+            stroked
+        });
+
+        // Use the original radius and stroke radius for the bounds so that it does not include the
+        // AA bloat.
+        radius += halfWidth;
+        batch->setBounds({ center.fX - radius, center.fY - radius,
+                         center.fX + radius, center.fY + radius },
+                         HasAABloat::kNo, IsZeroArea::kNo);
+        batch->fVertCount = circle_type_to_vert_count(stroked);
+        batch->fIndexCount = circle_type_to_index_count(stroked);
+        return batch;
+    }
+
+    const char* name() const override { return "ShadowCircleBatch"; }
+
+    SkString dumpInfo() const override {
+        SkString string;
+        for (int i = 0; i < fGeoData.count(); ++i) {
+            string.appendf("Color: 0x%08x Rect [L: %.2f, T: %.2f, R: %.2f, B: %.2f], "
+                           "OuterRad: %.2f, InnerRad: %.2f, BlurRad: %.2f\n",
+                           fGeoData[i].fColor,
+                           fGeoData[i].fDevBounds.fLeft, fGeoData[i].fDevBounds.fTop,
+                           fGeoData[i].fDevBounds.fRight, fGeoData[i].fDevBounds.fBottom,
+                           fGeoData[i].fOuterRadius, fGeoData[i].fInnerRadius,
+                           fGeoData[i].fBlurRadius);
+        }
+        string.append(INHERITED::dumpInfo());
+        return string;
+    }
+
+    void computePipelineOptimizations(GrInitInvariantOutput* color,
+                                      GrInitInvariantOutput* coverage,
+                                      GrBatchToXPOverrides* overrides) const override {
+        // When this is called on a batch, there is only one geometry bundle
+        color->setKnownFourComponents(fGeoData[0].fColor);
+        coverage->setUnknownSingleComponent();
+    }
+
+private:
+    ShadowCircleBatch() : INHERITED(ClassID()) {}
+    void initBatchTracker(const GrXPOverridesForBatch& overrides) override {
+        // Handle any overrides that affect our GP.
+        overrides.getOverrideColorIfSet(&fGeoData[0].fColor);
+        if (!overrides.readsLocalCoords()) {
+            fViewMatrixIfUsingLocalCoords.reset();
+        }
+    }
+
+    void onPrepareDraws(Target* target) const override {
+        SkMatrix localMatrix;
+        if (!fViewMatrixIfUsingLocalCoords.invert(&localMatrix)) {
+            return;
+        }
+
+        // Setup geometry processor
+        sk_sp<GrGeometryProcessor> gp(GrRRectShadowGeoProc::Make(localMatrix));
+
+        struct CircleVertex {
+            SkPoint  fPos;
+            GrColor  fColor;
+            SkPoint  fOffset;
+            SkScalar fOuterRadius;
+            SkScalar fBlurRadius;
+        };
+
+        int instanceCount = fGeoData.count();
+        size_t vertexStride = gp->getVertexStride();
+        SkASSERT(vertexStride == sizeof(CircleVertex));
+
+        const GrBuffer* vertexBuffer;
+        int firstVertex;
+        char* vertices = (char*)target->makeVertexSpace(vertexStride, fVertCount,
+                                                        &vertexBuffer, &firstVertex);
+        if (!vertices) {
+            SkDebugf("Could not allocate vertices\n");
+            return;
+        }
+
+        const GrBuffer* indexBuffer = nullptr;
+        int firstIndex = 0;
+        uint16_t* indices = target->makeIndexSpace(fIndexCount, &indexBuffer, &firstIndex);
+        if (!indices) {
+            SkDebugf("Could not allocate indices\n");
+            return;
+        }
+
+        int currStartVertex = 0;
+        for (int i = 0; i < instanceCount; i++) {
+            const Geometry& geom = fGeoData[i];
+
+            GrColor color = geom.fColor;
+            SkScalar outerRadius = geom.fOuterRadius;
+            SkScalar innerRadius = geom.fInnerRadius;
+            SkScalar blurRadius = geom.fBlurRadius;
+
+            const SkRect& bounds = geom.fDevBounds;
+            CircleVertex* ov0 = reinterpret_cast<CircleVertex*>(vertices + 0 * vertexStride);
+            CircleVertex* ov1 = reinterpret_cast<CircleVertex*>(vertices + 1 * vertexStride);
+            CircleVertex* ov2 = reinterpret_cast<CircleVertex*>(vertices + 2 * vertexStride);
+            CircleVertex* ov3 = reinterpret_cast<CircleVertex*>(vertices + 3 * vertexStride);
+            CircleVertex* ov4 = reinterpret_cast<CircleVertex*>(vertices + 4 * vertexStride);
+            CircleVertex* ov5 = reinterpret_cast<CircleVertex*>(vertices + 5 * vertexStride);
+            CircleVertex* ov6 = reinterpret_cast<CircleVertex*>(vertices + 6 * vertexStride);
+            CircleVertex* ov7 = reinterpret_cast<CircleVertex*>(vertices + 7 * vertexStride);
+
+            // The inner radius in the vertex data must be specified in normalized space.
+            innerRadius = innerRadius / outerRadius;
+            
+            SkPoint center = SkPoint::Make(bounds.centerX(), bounds.centerY());
+            SkScalar halfWidth = 0.5f*bounds.width();
+            SkScalar octOffset = 0.41421356237f;  // sqrt(2) - 1
+
+            ov0->fPos = center + SkPoint::Make(-octOffset*halfWidth, -halfWidth);
+            ov0->fColor = color;
+            ov0->fOffset = SkPoint::Make(-octOffset, -1);
+            ov0->fOuterRadius = outerRadius;
+            ov0->fBlurRadius = blurRadius;
+
+            ov1->fPos = center + SkPoint::Make(octOffset*halfWidth, -halfWidth);
+            ov1->fColor = color;
+            ov1->fOffset = SkPoint::Make(octOffset, -1);
+            ov1->fOuterRadius = outerRadius;
+            ov1->fBlurRadius = blurRadius;
+
+            ov2->fPos = center + SkPoint::Make(halfWidth, -octOffset*halfWidth);
+            ov2->fColor = color;
+            ov2->fOffset = SkPoint::Make(1, -octOffset);
+            ov2->fOuterRadius = outerRadius;
+            ov2->fBlurRadius = blurRadius;
+
+            ov3->fPos = center + SkPoint::Make(halfWidth, octOffset*halfWidth);
+            ov3->fColor = color;
+            ov3->fOffset = SkPoint::Make(1, octOffset);
+            ov3->fOuterRadius = outerRadius;
+            ov3->fBlurRadius = blurRadius;
+
+            ov4->fPos = center + SkPoint::Make(octOffset*halfWidth, halfWidth);
+            ov4->fColor = color;
+            ov4->fOffset = SkPoint::Make(octOffset, 1);
+            ov4->fOuterRadius = outerRadius;
+            ov4->fBlurRadius = blurRadius;
+
+            ov5->fPos = center + SkPoint::Make(-octOffset*halfWidth, halfWidth);
+            ov5->fColor = color;
+            ov5->fOffset = SkPoint::Make(-octOffset, 1);
+            ov5->fOuterRadius = outerRadius;
+            ov5->fBlurRadius = blurRadius;
+
+            ov6->fPos = center + SkPoint::Make(-halfWidth, octOffset*halfWidth);
+            ov6->fColor = color;
+            ov6->fOffset = SkPoint::Make(-1, octOffset);
+            ov6->fOuterRadius = outerRadius;
+            ov6->fBlurRadius = blurRadius;
+
+            ov7->fPos = center + SkPoint::Make(-halfWidth, -octOffset*halfWidth);
+            ov7->fColor = color;
+            ov7->fOffset = SkPoint::Make(-1, -octOffset);
+            ov7->fOuterRadius = outerRadius;
+            ov7->fBlurRadius = blurRadius;
+
+            if (geom.fStroked) {
+                // compute the inner ring
+                CircleVertex* iv0 = reinterpret_cast<CircleVertex*>(vertices + 8 * vertexStride);
+                CircleVertex* iv1 = reinterpret_cast<CircleVertex*>(vertices + 9 * vertexStride);
+                CircleVertex* iv2 = reinterpret_cast<CircleVertex*>(vertices + 10 * vertexStride);
+                CircleVertex* iv3 = reinterpret_cast<CircleVertex*>(vertices + 11 * vertexStride);
+                CircleVertex* iv4 = reinterpret_cast<CircleVertex*>(vertices + 12 * vertexStride);
+                CircleVertex* iv5 = reinterpret_cast<CircleVertex*>(vertices + 13 * vertexStride);
+                CircleVertex* iv6 = reinterpret_cast<CircleVertex*>(vertices + 14 * vertexStride);
+                CircleVertex* iv7 = reinterpret_cast<CircleVertex*>(vertices + 15 * vertexStride);
+
+                // cosine and sine of pi/8
+                SkScalar c = 0.923579533f;
+                SkScalar s = 0.382683432f;
+                SkScalar r = geom.fInnerRadius;
+
+                iv0->fPos = center + SkPoint::Make(-s*r, -c*r);
+                iv0->fColor = color;
+                iv0->fOffset = SkPoint::Make(-s*innerRadius, -c*innerRadius);
+                iv0->fOuterRadius = outerRadius;
+                iv0->fBlurRadius = blurRadius;
+
+                iv1->fPos = center + SkPoint::Make(s*r, -c*r);
+                iv1->fColor = color;
+                iv1->fOffset = SkPoint::Make(s*innerRadius, -c*innerRadius);
+                iv1->fOuterRadius = outerRadius;
+                iv1->fBlurRadius = blurRadius;
+
+                iv2->fPos = center + SkPoint::Make(c*r, -s*r);
+                iv2->fColor = color;
+                iv2->fOffset = SkPoint::Make(c*innerRadius, -s*innerRadius);
+                iv2->fOuterRadius = outerRadius;
+                iv2->fBlurRadius = blurRadius;
+
+                iv3->fPos = center + SkPoint::Make(c*r, s*r);
+                iv3->fColor = color;
+                iv3->fOffset = SkPoint::Make(c*innerRadius, s*innerRadius);
+                iv3->fOuterRadius = outerRadius;
+                iv3->fBlurRadius = blurRadius;
+
+                iv4->fPos = center + SkPoint::Make(s*r, c*r);
+                iv4->fColor = color;
+                iv4->fOffset = SkPoint::Make(s*innerRadius, c*innerRadius);
+                iv4->fOuterRadius = outerRadius;
+                iv4->fBlurRadius = blurRadius;
+
+                iv5->fPos = center + SkPoint::Make(-s*r, c*r);
+                iv5->fColor = color;
+                iv5->fOffset = SkPoint::Make(-s*innerRadius, c*innerRadius);
+                iv5->fOuterRadius = outerRadius;
+                iv5->fBlurRadius = blurRadius;
+
+                iv6->fPos = center + SkPoint::Make(-c*r, s*r);
+                iv6->fColor = color;
+                iv6->fOffset = SkPoint::Make(-c*innerRadius, s*innerRadius);
+                iv6->fOuterRadius = outerRadius;
+                iv6->fBlurRadius = blurRadius;
+
+                iv7->fPos = center + SkPoint::Make(-c*r, -s*r);
+                iv7->fColor = color;
+                iv7->fOffset = SkPoint::Make(-c*innerRadius, -s*innerRadius);
+                iv7->fOuterRadius = outerRadius;
+                iv7->fBlurRadius = blurRadius;
+            } else {
+                // filled
+                CircleVertex* iv = reinterpret_cast<CircleVertex*>(vertices + 8 * vertexStride);
+                iv->fPos = center;
+                iv->fColor = color;
+                iv->fOffset = SkPoint::Make(0, 0);
+                iv->fOuterRadius = outerRadius;
+                iv->fBlurRadius = blurRadius;
+            }
+
+            const uint16_t* primIndices = circle_type_to_indices(geom.fStroked);
+            const int primIndexCount = circle_type_to_index_count(geom.fStroked);
+            for (int i = 0; i < primIndexCount; ++i) {
+                *indices++ = primIndices[i] + currStartVertex;
+            }
+
+            currStartVertex += circle_type_to_vert_count(geom.fStroked);
+            vertices += circle_type_to_vert_count(geom.fStroked)*vertexStride;
+        }
+
+        GrMesh mesh;
+        mesh.initIndexed(kTriangles_GrPrimitiveType, vertexBuffer, indexBuffer, firstVertex,
+                         firstIndex, fVertCount, fIndexCount);
+        target->draw(gp.get(), mesh);
+    }
+
+    bool onCombineIfPossible(GrBatch* t, const GrCaps& caps) override {
+        ShadowCircleBatch* that = t->cast<ShadowCircleBatch>();
+        if (!GrPipeline::CanCombine(*this->pipeline(), this->bounds(), *that->pipeline(),
+                                    that->bounds(), caps)) {
+            return false;
+        }
+
+        if (!fViewMatrixIfUsingLocalCoords.cheapEqualTo(that->fViewMatrixIfUsingLocalCoords)) {
+            return false;
+        }
+
+        fGeoData.push_back_n(that->fGeoData.count(), that->fGeoData.begin());
+        this->joinBounds(*that);
+        fVertCount += that->fVertCount;
+        fIndexCount += that->fIndexCount;
+        return true;
+    }
+
+    struct Geometry {
+        GrColor  fColor;
+        SkScalar fOuterRadius;
+        SkScalar fInnerRadius;
+        SkScalar fBlurRadius;
+        SkRect   fDevBounds;
+        bool     fStroked;
+    };
+
+    SkSTArray<1, Geometry, true> fGeoData;
+    SkMatrix                     fViewMatrixIfUsingLocalCoords;
+    int                          fVertCount;
+    int                          fIndexCount;
+
+    typedef GrVertexBatch INHERITED;
+};
+
+///////////////////////////////////////////////////////////////////////////////////////////////////
+
+// We have two possible cases for geometry for a shadow roundrect.
+//
+// In the case of a normal stroke, we draw the roundrect as a 9-patch without the center quad.
+//    ____________
+//   |_|________|_|
+//   | |        | |
+//   | |        | |
+//   | |        | |
+//   |_|________|_|
+//   |_|________|_|
+//
+// In the case where the stroke width is greater than twice the corner radius (overstroke),
+// we add additional geometry to mark out the rectangle in the center. The shared vertices
+// are duplicated so we can set a different outer radius for the fill calculation.
+//    ____________
+//   |_|________|_|
+//   | |\ ____ /| |
+//   | | |    | | |
+//   | | |____| | |
+//   |_|/______\|_|
+//   |_|________|_|
+//
+// For filled rrects we reuse the overstroke geometry but make the inner rect degenerate
+// (either a point or a horizontal or vertical line).
+
+static const uint16_t gOverstrokeRRectIndices[] = {
+    // corners
+    0, 1, 5, 0, 5, 4,
+    2, 3, 7, 2, 7, 6,
+    8, 9, 13, 8, 13, 12,
+    10, 11, 15, 10, 15, 14,
+
+    // edges
+    1, 2, 6, 1, 6, 5,
+    4, 5, 9, 4, 9, 8,
+    6, 7, 11, 6, 11, 10,
+    9, 10, 14, 9, 14, 13,
+
+    // overstroke quads
+    // we place this at the end so that we can skip these indices when rendering as stroked
+    16, 17, 19, 16, 19, 18,
+    19, 17, 23, 19, 23, 21,
+    21, 23, 22, 21, 22, 20,
+    22, 16, 18, 22, 18, 20,
+};
+// standard stroke indices start at the same place, but will skip the overstroke "ring"
+static const uint16_t* gStrokeRRectIndices = gOverstrokeRRectIndices;
+
+// overstroke count
+static const int kIndicesPerOverstrokeRRect = SK_ARRAY_COUNT(gOverstrokeRRectIndices);
+// simple stroke count skips overstroke indices
+static const int kIndicesPerStrokeRRect = kIndicesPerOverstrokeRRect - 6 * 4 + 6;
+static const int kVertsPerStrokeRRect = 16;
+static const int kVertsPerOverstrokeRRect = 24;
+
+enum RRectType {
+    kFill_RRectType,
+    kStroke_RRectType,
+    kOverstroke_RRectType,
+};
+
+static int rrect_type_to_vert_count(RRectType type) {
+    static const int kTypeToVertCount[] = {
+        kVertsPerOverstrokeRRect,
+        kVertsPerStrokeRRect,
+        kVertsPerOverstrokeRRect,
+    };
+
+    return kTypeToVertCount[type];
+}
+
+static int rrect_type_to_index_count(RRectType type) {
+    static const int kTypeToIndexCount[] = {
+        kIndicesPerOverstrokeRRect,
+        kIndicesPerStrokeRRect,
+        kIndicesPerOverstrokeRRect,
+    };
+
+    return kTypeToIndexCount[type];
+}
+
+static const uint16_t* rrect_type_to_indices(RRectType type) {
+    static const uint16_t* kTypeToIndices[] = {
+        gOverstrokeRRectIndices,
+        gStrokeRRectIndices,
+        gOverstrokeRRectIndices,
+    };
+
+    return kTypeToIndices[type];
+}
+
+// For distance computations in the interior of filled rrects we:
+//
+//   add a interior degenerate (point or line) rect
+//   each vertex of that rect gets -outerRad as its radius
+//      this makes the computation of the distance to the outer edge be negative
+//      negative values are caught and then handled differently in the GP's onEmitCode
+//   each vertex is also given the normalized x & y distance from the interior rect's edge
+//      the GP takes the min of those depths +1 to get the normalized distance to the outer edge
+
+class ShadowCircularRRectBatch : public GrVertexBatch {
+public:
+    DEFINE_BATCH_CLASS_ID
+
+    // A devStrokeWidth <= 0 indicates a fill only. If devStrokeWidth > 0 then strokeOnly indicates
+    // whether the rrect is only stroked or stroked and filled.
+    ShadowCircularRRectBatch(GrColor color, const SkMatrix& viewMatrix,
+                             const SkRect& devRect, float devRadius, float blurRadius,
+                             float devStrokeWidth, bool strokeOnly)
+        : INHERITED(ClassID())
+        , fViewMatrixIfUsingLocalCoords(viewMatrix) {
+        SkRect bounds = devRect;
+        SkASSERT(!(devStrokeWidth <= 0 && strokeOnly));
+        SkScalar innerRadius = 0.0f;
+        SkScalar outerRadius = devRadius;
+        SkScalar halfWidth = 0;
+        RRectType type = kFill_RRectType;
+        if (devStrokeWidth > 0) {
+            if (SkScalarNearlyZero(devStrokeWidth)) {
+                halfWidth = SK_ScalarHalf;
+            } else {
+                halfWidth = SkScalarHalf(devStrokeWidth);
+            }
+
+            if (strokeOnly) {
+                // Outset stroke by 1/4 pixel
+                devStrokeWidth += 0.25f;
+                // If stroke is greater than width or height, this is still a fill
+                // Otherwise we compute stroke params
+                if (devStrokeWidth <= devRect.width() &&
+                    devStrokeWidth <= devRect.height()) {
+                    innerRadius = devRadius - halfWidth;
+                    type = (innerRadius >= 0) ? kStroke_RRectType : kOverstroke_RRectType;
+                }
+            }
+            outerRadius += halfWidth;
+            bounds.outset(halfWidth, halfWidth);
+        }
+
+        // TODO: still needed?
+        // The radii are outset for two reasons. First, it allows the shader to simply perform
+        // simpler computation because the computed alpha is zero, rather than 50%, at the radius.
+        // Second, the outer radius is used to compute the verts of the bounding box that is
+        // rendered and the outset ensures the box will cover all partially covered by the rrect
+        // corners.
+        outerRadius += SK_ScalarHalf;
+        innerRadius -= SK_ScalarHalf;
+
+        this->setBounds(bounds, HasAABloat::kYes, IsZeroArea::kNo);
+
+        // Expand the rect for aa to generate correct vertices.
+        bounds.outset(SK_ScalarHalf, SK_ScalarHalf);
+
+        fGeoData.emplace_back(Geometry{color, outerRadius, innerRadius, blurRadius, bounds, type});
+        fVertCount = rrect_type_to_vert_count(type);
+        fIndexCount = rrect_type_to_index_count(type);
+    }
+
+    const char* name() const override { return "ShadowCircularRRectBatch"; }
+
+    SkString dumpInfo() const override {
+        SkString string;
+        for (int i = 0; i < fGeoData.count(); ++i) {
+            string.appendf("Color: 0x%08x Rect [L: %.2f, T: %.2f, R: %.2f, B: %.2f],"
+                           "OuterRad: %.2f, InnerRad: %.2f, BlurRad: %.2f\n",
+                           fGeoData[i].fColor,
+                           fGeoData[i].fDevBounds.fLeft, fGeoData[i].fDevBounds.fTop,
+                           fGeoData[i].fDevBounds.fRight, fGeoData[i].fDevBounds.fBottom,
+                           fGeoData[i].fOuterRadius, fGeoData[i].fInnerRadius,
+                           fGeoData[i].fBlurRadius);
+        }
+        string.append(INHERITED::dumpInfo());
+        return string;
+    }
+
+    void computePipelineOptimizations(GrInitInvariantOutput* color,
+                                      GrInitInvariantOutput* coverage,
+                                      GrBatchToXPOverrides* overrides) const override {
+        // When this is called on a batch, there is only one geometry bundle
+        color->setKnownFourComponents(fGeoData[0].fColor);
+        coverage->setUnknownSingleComponent();
+    }
+
+private:
+    void initBatchTracker(const GrXPOverridesForBatch& overrides) override {
+        // Handle any overrides that affect our GP.
+        overrides.getOverrideColorIfSet(&fGeoData[0].fColor);
+        if (!overrides.readsLocalCoords()) {
+            fViewMatrixIfUsingLocalCoords.reset();
+        }
+    }
+
+    struct CircleVertex {
+        SkPoint  fPos;
+        GrColor  fColor;
+        SkPoint  fOffset;
+        SkScalar fOuterRadius;
+        SkScalar fBlurRadius;
+    };
+
+    static void FillInOverstrokeVerts(CircleVertex** verts, const SkRect& bounds,
+                                      SkScalar smInset, SkScalar bigInset, SkScalar xOffset,
+                                      SkScalar outerRadius, GrColor color, SkScalar blurRadius) {
+        SkASSERT(smInset < bigInset);
+
+        // TL
+        (*verts)->fPos = SkPoint::Make(bounds.fLeft + smInset, bounds.fTop + smInset);
+        (*verts)->fColor = color;
+        (*verts)->fOffset = SkPoint::Make(xOffset, 0);
+        (*verts)->fOuterRadius = outerRadius;
+        (*verts)->fBlurRadius = blurRadius;
+        (*verts)++;
+
+        // TR
+        (*verts)->fPos = SkPoint::Make(bounds.fRight - smInset, bounds.fTop + smInset);
+        (*verts)->fColor = color;
+        (*verts)->fOffset = SkPoint::Make(xOffset, 0);
+        (*verts)->fOuterRadius = outerRadius;
+        (*verts)->fBlurRadius = blurRadius;
+        (*verts)++;
+
+        (*verts)->fPos = SkPoint::Make(bounds.fLeft + bigInset, bounds.fTop + bigInset);
+        (*verts)->fColor = color;
+        (*verts)->fOffset = SkPoint::Make(0, 0);
+        (*verts)->fOuterRadius = outerRadius;
+        (*verts)->fBlurRadius = blurRadius;
+        (*verts)++;
+
+        (*verts)->fPos = SkPoint::Make(bounds.fRight - bigInset, bounds.fTop + bigInset);
+        (*verts)->fColor = color;
+        (*verts)->fOffset = SkPoint::Make(0, 0);
+        (*verts)->fOuterRadius = outerRadius;
+        (*verts)->fBlurRadius = blurRadius;
+        (*verts)++;
+
+        (*verts)->fPos = SkPoint::Make(bounds.fLeft + bigInset, bounds.fBottom - bigInset);
+        (*verts)->fColor = color;
+        (*verts)->fOffset = SkPoint::Make(0, 0);
+        (*verts)->fOuterRadius = outerRadius;
+        (*verts)->fBlurRadius = blurRadius;
+        (*verts)++;
+
+        (*verts)->fPos = SkPoint::Make(bounds.fRight - bigInset, bounds.fBottom - bigInset);
+        (*verts)->fColor = color;
+        (*verts)->fOffset = SkPoint::Make(0, 0);
+        (*verts)->fOuterRadius = outerRadius;
+        (*verts)->fBlurRadius = blurRadius;
+        (*verts)++;
+
+        // BL
+        (*verts)->fPos = SkPoint::Make(bounds.fLeft + smInset, bounds.fBottom - smInset);
+        (*verts)->fColor = color;
+        (*verts)->fOffset = SkPoint::Make(xOffset, 0);
+        (*verts)->fOuterRadius = outerRadius;
+        (*verts)->fBlurRadius = blurRadius;
+        (*verts)++;
+
+        // BR
+        (*verts)->fPos = SkPoint::Make(bounds.fRight - smInset, bounds.fBottom - smInset);
+        (*verts)->fColor = color;
+        (*verts)->fOffset = SkPoint::Make(xOffset, 0);
+        (*verts)->fOuterRadius = outerRadius;
+        (*verts)->fBlurRadius = blurRadius;
+        (*verts)++;
+    }
+
+    void onPrepareDraws(Target* target) const override {
+        // Invert the view matrix as a local matrix (if any other processors require coords).
+        SkMatrix localMatrix;
+        if (!fViewMatrixIfUsingLocalCoords.invert(&localMatrix)) {
+            return;
+        }
+
+        // Setup geometry processor
+        sk_sp<GrGeometryProcessor> gp(GrRRectShadowGeoProc::Make(localMatrix));
+
+        int instanceCount = fGeoData.count();
+        size_t vertexStride = gp->getVertexStride();
+        SkASSERT(sizeof(CircleVertex) == vertexStride);
+
+        const GrBuffer* vertexBuffer;
+        int firstVertex;
+
+        CircleVertex* verts = (CircleVertex*)target->makeVertexSpace(vertexStride, fVertCount,
+                                                                     &vertexBuffer, &firstVertex);
+        if (!verts) {
+            SkDebugf("Could not allocate vertices\n");
+            return;
+        }
+
+        const GrBuffer* indexBuffer = nullptr;
+        int firstIndex = 0;
+        uint16_t* indices = target->makeIndexSpace(fIndexCount, &indexBuffer, &firstIndex);
+        if (!indices) {
+            SkDebugf("Could not allocate indices\n");
+            return;
+        }
+
+        int currStartVertex = 0;
+        for (int i = 0; i < instanceCount; i++) {
+            const Geometry& args = fGeoData[i];
+
+            GrColor color = args.fColor;
+            SkScalar outerRadius = args.fOuterRadius;
+
+            const SkRect& bounds = args.fDevBounds;
+
+            SkScalar yCoords[4] = {
+                bounds.fTop,
+                bounds.fTop + outerRadius,
+                bounds.fBottom - outerRadius,
+                bounds.fBottom
+            };
+
+            SkScalar yOuterRadii[4] = { -1, 0, 0, 1 };
+            // The inner radius in the vertex data must be specified in normalized space.
+            // For fills, specifying -1/outerRadius guarantees an alpha of 1.0 at the inner radius.
+            SkScalar blurRadius = args.fBlurRadius;
+            for (int i = 0; i < 4; ++i) {
+                verts->fPos = SkPoint::Make(bounds.fLeft, yCoords[i]);
+                verts->fColor = color;
+                verts->fOffset = SkPoint::Make(-1, yOuterRadii[i]);
+                verts->fOuterRadius = outerRadius;
+                verts->fBlurRadius = blurRadius;
+                verts++;
+
+                verts->fPos = SkPoint::Make(bounds.fLeft + outerRadius, yCoords[i]);
+                verts->fColor = color;
+                verts->fOffset = SkPoint::Make(0, yOuterRadii[i]);
+                verts->fOuterRadius = outerRadius;
+                verts->fBlurRadius = blurRadius;
+                verts++;
+
+                verts->fPos = SkPoint::Make(bounds.fRight - outerRadius, yCoords[i]);
+                verts->fColor = color;
+                verts->fOffset = SkPoint::Make(0, yOuterRadii[i]);
+                verts->fOuterRadius = outerRadius;
+                verts->fBlurRadius = blurRadius;
+                verts++;
+
+                verts->fPos = SkPoint::Make(bounds.fRight, yCoords[i]);
+                verts->fColor = color;
+                verts->fOffset = SkPoint::Make(1, yOuterRadii[i]);
+                verts->fOuterRadius = outerRadius;
+                verts->fBlurRadius = blurRadius;
+                verts++;
+            }
+            // Add the additional vertices for overstroked rrects.
+            // Effectively this is an additional stroked rrect, with its
+            // outer radius = outerRadius - innerRadius, and inner radius = 0.
+            // This will give us correct AA in the center and the correct
+            // distance to the outer edge.
+            //
+            // Also, the outer offset is a constant vector pointing to the right, which
+            // guarantees that the distance value along the outer rectangle is constant.
+            if (kOverstroke_RRectType == args.fType) {
+                SkASSERT(args.fInnerRadius <= 0.0f);
+
+                SkScalar overstrokeOuterRadius = outerRadius - args.fInnerRadius;
+                // this is the normalized distance from the outer rectangle of this
+                // geometry to the outer edge
+                SkScalar maxOffset = -args.fInnerRadius / overstrokeOuterRadius;
+
+                FillInOverstrokeVerts(&verts, bounds, outerRadius, overstrokeOuterRadius,
+                                      maxOffset, overstrokeOuterRadius, color, blurRadius);
+            }
+
+            if (kFill_RRectType == args.fType) {
+                SkScalar halfMinDim = 0.5f * SkTMin(bounds.width(), bounds.height());
+
+                SkScalar xOffset = 1.0f - outerRadius / halfMinDim;
+
+                FillInOverstrokeVerts(&verts, bounds, outerRadius, halfMinDim,
+                                      xOffset, halfMinDim, color, blurRadius);
+            }
+
+            const uint16_t* primIndices = rrect_type_to_indices(args.fType);
+            const int primIndexCount = rrect_type_to_index_count(args.fType);
+            for (int i = 0; i < primIndexCount; ++i) {
+                *indices++ = primIndices[i] + currStartVertex;
+            }
+
+            currStartVertex += rrect_type_to_vert_count(args.fType);
+        }
+
+        GrMesh mesh;
+        mesh.initIndexed(kTriangles_GrPrimitiveType, vertexBuffer, indexBuffer, firstVertex,
+                         firstIndex, fVertCount, fIndexCount);
+        target->draw(gp.get(), mesh);
+    }
+
+    bool onCombineIfPossible(GrBatch* t, const GrCaps& caps) override {
+        ShadowCircularRRectBatch* that = t->cast<ShadowCircularRRectBatch>();
+        if (!GrPipeline::CanCombine(*this->pipeline(), this->bounds(), *that->pipeline(),
+                                    that->bounds(), caps)) {
+            return false;
+        }
+
+        if (!fViewMatrixIfUsingLocalCoords.cheapEqualTo(that->fViewMatrixIfUsingLocalCoords)) {
+            return false;
+        }
+
+        fGeoData.push_back_n(that->fGeoData.count(), that->fGeoData.begin());
+        this->joinBounds(*that);
+        fVertCount += that->fVertCount;
+        fIndexCount += that->fIndexCount;
+        return true;
+    }
+
+    struct Geometry {
+        GrColor  fColor;
+        SkScalar fOuterRadius;
+        SkScalar fInnerRadius;
+        SkScalar fBlurRadius;
+        SkRect fDevBounds;
+        RRectType fType;
+    };
+
+    SkSTArray<1, Geometry, true> fGeoData;
+    SkMatrix                     fViewMatrixIfUsingLocalCoords;
+    int                          fVertCount;
+    int                          fIndexCount;
+
+    typedef GrVertexBatch INHERITED;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+
+static GrDrawBatch* create_shadow_circle_batch(GrColor color,
+                                               const SkMatrix& viewMatrix,
+                                               const SkRect& oval,
+                                               SkScalar blurRadius,
+                                               const SkStrokeRec& stroke,
+                                               const GrShaderCaps* shaderCaps) {
+    // we can only draw circles
+    SkScalar width = oval.width();
+    SkASSERT(SkScalarNearlyEqual(width, oval.height()) && viewMatrix.isSimilarity());
+    SkPoint center = { oval.centerX(), oval.centerY() };
+    return ShadowCircleBatch::Create(color, viewMatrix, center, width / 2.f,
+                                     blurRadius, GrStyle(stroke, nullptr));
+}
+
+static GrDrawBatch* create_shadow_rrect_batch(GrColor color,
+                                              const SkMatrix& viewMatrix,
+                                              const SkRRect& rrect,
+                                              SkScalar blurRadius,
+                                              const SkStrokeRec& stroke) {
+    SkASSERT(viewMatrix.rectStaysRect());
+    SkASSERT(rrect.isSimple());
+    SkASSERT(!rrect.isOval());
+
+    // Shadow rrect batchs only handle simple circular rrects
+    // do any matrix crunching before we reset the draw state for device coords
+    const SkRect& rrectBounds = rrect.getBounds();
+    SkRect bounds;
+    viewMatrix.mapRect(&bounds, rrectBounds);
+
+    SkVector radii = rrect.getSimpleRadii();
+    SkScalar xRadius = SkScalarAbs(viewMatrix[SkMatrix::kMScaleX] * radii.fX +
+                                   viewMatrix[SkMatrix::kMSkewY] * radii.fY);
+    SkScalar yRadius = SkScalarAbs(viewMatrix[SkMatrix::kMSkewX] * radii.fX +
+                                   viewMatrix[SkMatrix::kMScaleY] * radii.fY);
+    SkASSERT(SkScalarNearlyEqual(xRadius, yRadius));
+
+    SkStrokeRec::Style style = stroke.getStyle();
+
+    // Do (potentially) anisotropic mapping of stroke. Use -1s to indicate fill-only draws.
+    SkVector scaledStroke = { -1, -1 };
+    SkScalar strokeWidth = stroke.getWidth();
+
+    bool isStrokeOnly = SkStrokeRec::kStroke_Style == style ||
+                        SkStrokeRec::kHairline_Style == style;
+    bool hasStroke = isStrokeOnly || SkStrokeRec::kStrokeAndFill_Style == style;
+
+    if (hasStroke) {
+        if (SkStrokeRec::kHairline_Style == style) {
+            scaledStroke.set(1, 1);
+        } else {
+            scaledStroke.fX = SkScalarAbs(strokeWidth*(viewMatrix[SkMatrix::kMScaleX] +
+                                                       viewMatrix[SkMatrix::kMSkewY]));
+            scaledStroke.fY = SkScalarAbs(strokeWidth*(viewMatrix[SkMatrix::kMSkewX] +
+                                                       viewMatrix[SkMatrix::kMScaleY]));
+        }
+
+        // we don't handle anisotropic strokes
+        if (!SkScalarNearlyEqual(scaledStroke.fX, scaledStroke.fY)) {
+            return nullptr;
+        }
+    }
+
+    // The way the effect interpolates the offset-to-ellipse/circle-center attribute only works on
+    // the interior of the rrect if the radii are >= 0.5. Otherwise, the inner rect of the nine-
+    // patch will have fractional coverage. This only matters when the interior is actually filled.
+    // We could consider falling back to rect rendering here, since a tiny radius is
+    // indistinguishable from a square corner.
+    if (!isStrokeOnly && (SK_ScalarHalf > xRadius || SK_ScalarHalf > yRadius)) {
+        return nullptr;
+    }
+
+    return new ShadowCircularRRectBatch(color, viewMatrix, bounds, xRadius,
+                                        blurRadius, scaledStroke.fX, isStrokeOnly);
+}
+
+GrDrawBatch* CreateShadowRRectBatch(GrColor color,
+                                    const SkMatrix& viewMatrix,
+                                    const SkRRect& rrect,
+                                    const SkScalar blurRadius,
+                                    const SkStrokeRec& stroke,
+                                    const GrShaderCaps* shaderCaps) {
+    if (rrect.isOval()) {
+        return create_shadow_circle_batch(color, viewMatrix, rrect.getBounds(),
+                                          blurRadius, stroke, shaderCaps);
+    }
+
+    if (!viewMatrix.rectStaysRect() || !rrect.isSimple()) {
+        return nullptr;
+    }
+
+    return create_shadow_rrect_batch(color, viewMatrix, rrect, blurRadius, stroke);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+#ifdef GR_TEST_UTILS
+
+DRAW_BATCH_TEST_DEFINE(ShadowCircleBatch) {
+    do {
+        SkScalar rotate = random->nextSScalar1() * 360.f;
+        SkScalar translateX = random->nextSScalar1() * 1000.f;
+        SkScalar translateY = random->nextSScalar1() * 1000.f;
+        SkScalar scale = random->nextSScalar1() * 100.f;
+        SkMatrix viewMatrix;
+        viewMatrix.setRotate(rotate);
+        viewMatrix.postTranslate(translateX, translateY);
+        viewMatrix.postScale(scale, scale);
+        GrColor color = GrRandomColor(random);
+        SkRect circle = GrTest::TestSquare(random);
+        SkPoint center = { circle.centerX(), circle.centerY() };
+        SkScalar radius = circle.width() / 2.f;
+        SkStrokeRec stroke = GrTest::TestStrokeRec(random);
+        SkScalar blurRadius = random->nextSScalar1() * 72.f;
+        GrDrawBatch* batch = ShadowCircleBatch::Create(color, viewMatrix, center, radius,
+                                                       blurRadius, GrStyle(stroke, nullptr));
+        if (batch) {
+            return batch;
+        }
+    } while (true);
+}
+
+DRAW_BATCH_TEST_DEFINE(ShadowRRectBatch) {
+    SkMatrix viewMatrix = GrTest::TestMatrixRectStaysRect(random);
+    GrColor color = GrRandomColor(random);
+    const SkRRect& rrect = GrTest::TestRRectSimple(random);
+    SkScalar blurRadius = random->nextSScalar1() * 72.f;
+    return create_shadow_rrect_batch(color, viewMatrix, rrect,
+                                     blurRadius, GrTest::TestStrokeRec(random));
+}
+
+#endif