Give strokerectbatch a proper home

src/gpu/GrStrokeRectBatch.h

+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrStrokeRectBatch_DEFINED
+#define GrStrokeRectBatch_DEFINED
+
+#include "GrBatch.h"
+#include "GrColor.h"
+#include "GrDefaultGeoProcFactory.h"
+
+class GrStrokeRectBatch : public GrBatch {
+public:
+    struct Geometry {
+        GrColor fColor;
+        SkMatrix fViewMatrix;
+        SkRect fRect;
+        SkScalar fStrokeWidth;
+    };
+
+    static GrBatch* Create(const Geometry& geometry, bool snapToPixelCenters) {
+        return SkNEW_ARGS(GrStrokeRectBatch, (geometry, snapToPixelCenters));
+    }
+
+    const char* name() const override { return "GrStrokeRectBatch"; }
+
+    void getInvariantOutputColor(GrInitInvariantOutput* out) const override {
+        // When this is called on a batch, there is only one geometry bundle
+        out->setKnownFourComponents(fGeoData[0].fColor);
+    }
+
+    void getInvariantOutputCoverage(GrInitInvariantOutput* out) const override {
+        out->setKnownSingleComponent(0xff);
+    }
+
+    void initBatchTracker(const GrPipelineInfo& init) override {
+        // Handle any color overrides
+        if (!init.readsColor()) {
+            fGeoData[0].fColor = GrColor_ILLEGAL;
+        }
+        init.getOverrideColorIfSet(&fGeoData[0].fColor);
+
+        // setup batch properties
+        fBatch.fColorIgnored = !init.readsColor();
+        fBatch.fColor = fGeoData[0].fColor;
+        fBatch.fUsesLocalCoords = init.readsLocalCoords();
+        fBatch.fCoverageIgnored = !init.readsCoverage();
+    }
+
+    void generateGeometry(GrBatchTarget* batchTarget, const GrPipeline* pipeline) override {
+        SkAutoTUnref<const GrGeometryProcessor> gp;
+        {
+            using namespace GrDefaultGeoProcFactory;
+            Color color(this->color());
+            Coverage coverage(this->coverageIgnored() ? Coverage::kSolid_Type :
+                                                        Coverage::kNone_Type);
+            LocalCoords localCoords(this->usesLocalCoords() ? LocalCoords::kUsePosition_Type :
+                                                              LocalCoords::kUnused_Type);
+            gp.reset(GrDefaultGeoProcFactory::Create(color, coverage, localCoords,
+                                                     this->viewMatrix()));
+        }
+
+        batchTarget->initDraw(gp, pipeline);
+
+        size_t vertexStride = gp->getVertexStride();
+
+        SkASSERT(vertexStride == sizeof(GrDefaultGeoProcFactory::PositionAttr));
+
+        Geometry& args = fGeoData[0];
+
+        int vertexCount = kVertsPerHairlineRect;
+        if (args.fStrokeWidth > 0) {
+            vertexCount = kVertsPerStrokeRect;
+        }
+
+        const GrVertexBuffer* vertexBuffer;
+        int firstVertex;
+
+        void* verts = batchTarget->makeVertSpace(vertexStride, vertexCount,
+                                                 &vertexBuffer, &firstVertex);
+
+        if (!verts) {
+            SkDebugf("Could not allocate vertices\n");
+            return;
+        }
+
+        SkPoint* vertex = reinterpret_cast<SkPoint*>(verts);
+
+        GrPrimitiveType primType;
+
+        if (args.fStrokeWidth > 0) {;
+            primType = kTriangleStrip_GrPrimitiveType;
+            args.fRect.sort();
+            this->setStrokeRectStrip(vertex, args.fRect, args.fStrokeWidth);
+        } else {
+            // hairline
+            primType = kLineStrip_GrPrimitiveType;
+            vertex[0].set(args.fRect.fLeft, args.fRect.fTop);
+            vertex[1].set(args.fRect.fRight, args.fRect.fTop);
+            vertex[2].set(args.fRect.fRight, args.fRect.fBottom);
+            vertex[3].set(args.fRect.fLeft, args.fRect.fBottom);
+            vertex[4].set(args.fRect.fLeft, args.fRect.fTop);
+        }
+
+        GrVertices vertices;
+        vertices.init(primType, vertexBuffer, firstVertex, vertexCount);
+        batchTarget->draw(vertices);
+    }
+
+    SkSTArray<1, Geometry, true>* geoData() { return &fGeoData; }
+
+private:
+    GrStrokeRectBatch(const Geometry& geometry, bool snapToPixelCenters) {
+        this->initClassID<GrStrokeRectBatch>();
+
+        fBatch.fHairline = geometry.fStrokeWidth == 0;
+
+        fGeoData.push_back(geometry);
+
+        // setup bounds
+        fBounds = geometry.fRect;
+        SkScalar rad = SkScalarHalf(geometry.fStrokeWidth);
+        fBounds.outset(rad, rad);
+        geometry.fViewMatrix.mapRect(&fBounds);
+
+        // If our caller snaps to pixel centers then we have to round out the bounds
+        if (snapToPixelCenters) {
+            fBounds.roundOut();
+        }
+    }
+
+    /*  create a triangle strip that strokes the specified rect. There are 8
+     unique vertices, but we repeat the last 2 to close up. Alternatively we
+     could use an indices array, and then only send 8 verts, but not sure that
+     would be faster.
+     */
+    void setStrokeRectStrip(SkPoint verts[10], const SkRect& rect, SkScalar width) {
+        const SkScalar rad = SkScalarHalf(width);
+        // TODO we should be able to enable this assert, but we'd have to filter these draws
+        // this is a bug
+        //SkASSERT(rad < rect.width() / 2 && rad < rect.height() / 2);
+
+        verts[0].set(rect.fLeft + rad, rect.fTop + rad);
+        verts[1].set(rect.fLeft - rad, rect.fTop - rad);
+        verts[2].set(rect.fRight - rad, rect.fTop + rad);
+        verts[3].set(rect.fRight + rad, rect.fTop - rad);
+        verts[4].set(rect.fRight - rad, rect.fBottom - rad);
+        verts[5].set(rect.fRight + rad, rect.fBottom + rad);
+        verts[6].set(rect.fLeft + rad, rect.fBottom - rad);
+        verts[7].set(rect.fLeft - rad, rect.fBottom + rad);
+        verts[8] = verts[0];
+        verts[9] = verts[1];
+    }
+
+
+    GrColor color() const { return fBatch.fColor; }
+    bool usesLocalCoords() const { return fBatch.fUsesLocalCoords; }
+    bool colorIgnored() const { return fBatch.fColorIgnored; }
+    const SkMatrix& viewMatrix() const { return fGeoData[0].fViewMatrix; }
+    bool hairline() const { return fBatch.fHairline; }
+    bool coverageIgnored() const { return fBatch.fCoverageIgnored; }
+
+    bool onCombineIfPossible(GrBatch* t) override {
+        //if (!this->pipeline()->isEqual(*t->pipeline())) {
+        //    return false;
+        //}
+        // GrStrokeRectBatch* that = t->cast<StrokeRectBatch>();
+
+        // NonAA stroke rects cannot batch right now
+        // TODO make these batchable
+        return false;
+    }
+
+    struct BatchTracker {
+        GrColor fColor;
+        bool fUsesLocalCoords;
+        bool fColorIgnored;
+        bool fCoverageIgnored;
+        bool fHairline;
+    };
+
+    const static int kVertsPerHairlineRect = 5;
+    const static int kVertsPerStrokeRect = 10;
+
+    BatchTracker fBatch;
+    SkSTArray<1, Geometry, true> fGeoData;
+};
+
+#endif