C++ SkTLazy::init方法代码示例

    void onPrepareDraws(Target* target) const override {

        SkMatrix invert;
        if (fUsesLocalCoords && !fViewMatrix.invert(&invert)) {
            SkDebugf("Could not invert viewmatrix\n");
            return;
        }

        // Setup GrGeometryProcessors
        SkAutoTUnref<GrPLSGeometryProcessor> triangleProcessor(
                PLSAATriangleEffect::Create(invert, fUsesLocalCoords));
        SkAutoTUnref<GrPLSGeometryProcessor> quadProcessor(
                PLSQuadEdgeEffect::Create(invert, fUsesLocalCoords));

        GrResourceProvider* rp = target->resourceProvider();
        SkRect bounds;
        this->bounds().roundOut(&bounds);
        triangleProcessor->setBounds(bounds);
        quadProcessor->setBounds(bounds);

        // We use the fact that SkPath::transform path does subdivision based on
        // perspective. Otherwise, we apply the view matrix when copying to the
        // segment representation.
        const SkMatrix* viewMatrix = &fViewMatrix;

        // We avoid initializing the path unless we have to
        const SkPath* pathPtr = &fPath;
        SkTLazy<SkPath> tmpPath;
        if (viewMatrix->hasPerspective()) {
            SkPath* tmpPathPtr = tmpPath.init(*pathPtr);
            tmpPathPtr->setIsVolatile(true);
            tmpPathPtr->transform(*viewMatrix);
            viewMatrix = &SkMatrix::I();
            pathPtr = tmpPathPtr;
        }

        GrMesh mesh;

        PLSVertices triVertices;
        PLSVertices quadVertices;
        if (!get_geometry(*pathPtr, *viewMatrix, triVertices, quadVertices, rp, bounds)) {
            return;
        }

        if (triVertices.count()) {
            const GrBuffer* triVertexBuffer;
            int firstTriVertex;
            size_t triStride = triangleProcessor->getVertexStride();
            PLSVertex* triVerts = reinterpret_cast<PLSVertex*>(target->makeVertexSpace(
                    triStride, triVertices.count(), &triVertexBuffer, &firstTriVertex));
            if (!triVerts) {
                SkDebugf("Could not allocate vertices\n");
                return;
            }
            for (int i = 0; i < triVertices.count(); ++i) {
                triVerts[i] = triVertices[i];
            }
            mesh.init(kTriangles_GrPrimitiveType, triVertexBuffer, firstTriVertex,
                      triVertices.count());
            target->draw(triangleProcessor, mesh);
        }

        if (quadVertices.count()) {
            const GrBuffer* quadVertexBuffer;
            int firstQuadVertex;
            size_t quadStride = quadProcessor->getVertexStride();
            PLSVertex* quadVerts = reinterpret_cast<PLSVertex*>(target->makeVertexSpace(
                    quadStride, quadVertices.count(), &quadVertexBuffer, &firstQuadVertex));
            if (!quadVerts) {
                SkDebugf("Could not allocate vertices\n");
                return;
            }
            for (int i = 0; i < quadVertices.count(); ++i) {
                quadVerts[i] = quadVertices[i];
            }
            mesh.init(kTriangles_GrPrimitiveType, quadVertexBuffer, firstQuadVertex,
                      quadVertices.count());
            target->draw(quadProcessor, mesh);
        }

        SkAutoTUnref<GrGeometryProcessor> finishProcessor(
                PLSFinishEffect::Create(fColor,
                                        pathPtr->getFillType() ==
                                                            SkPath::FillType::kEvenOdd_FillType,
                                        invert,
                                        fUsesLocalCoords));
        const GrBuffer* rectVertexBuffer;
        size_t finishStride = finishProcessor->getVertexStride();
        int firstRectVertex;
        static const int kRectVertexCount = 6;
        SkPoint* rectVerts = reinterpret_cast<SkPoint*>(target->makeVertexSpace(
                finishStride, kRectVertexCount, &rectVertexBuffer, &firstRectVertex));
        if (!rectVerts) {
            SkDebugf("Could not allocate vertices\n");
            return;
        }
        rectVerts[0] = { bounds.fLeft, bounds.fTop };
        rectVerts[1] = { bounds.fLeft, bounds.fBottom };
        rectVerts[2] = { bounds.fRight, bounds.fBottom };
        rectVerts[3] = { bounds.fLeft, bounds.fTop };
//.........这里部分代码省略.........

    void onPrepareDraws(Target* target) const override {
#ifndef SK_IGNORE_LINEONLY_AA_CONVEX_PATH_OPTS
        if (this->linesOnly()) {
            this->prepareLinesOnlyDraws(target);
            return;
        }
#endif

        int instanceCount = fGeoData.count();

        SkMatrix invert;
        if (this->usesLocalCoords() && !this->viewMatrix().invert(&invert)) {
            SkDebugf("Could not invert viewmatrix\n");
            return;
        }

        // Setup GrGeometryProcessor
        sk_sp<GrGeometryProcessor> quadProcessor(
                QuadEdgeEffect::Make(this->color(), invert, this->usesLocalCoords()));

        // TODO generate all segments for all paths and use one vertex buffer
        for (int i = 0; i < instanceCount; i++) {
            const Geometry& args = fGeoData[i];

            // We use the fact that SkPath::transform path does subdivision based on
            // perspective. Otherwise, we apply the view matrix when copying to the
            // segment representation.
            const SkMatrix* viewMatrix = &args.fViewMatrix;

            // We avoid initializing the path unless we have to
            const SkPath* pathPtr = &args.fPath;
            SkTLazy<SkPath> tmpPath;
            if (viewMatrix->hasPerspective()) {
                SkPath* tmpPathPtr = tmpPath.init(*pathPtr);
                tmpPathPtr->setIsVolatile(true);
                tmpPathPtr->transform(*viewMatrix);
                viewMatrix = &SkMatrix::I();
                pathPtr = tmpPathPtr;
            }

            int vertexCount;
            int indexCount;
            enum {
                kPreallocSegmentCnt = 512 / sizeof(Segment),
                kPreallocDrawCnt = 4,
            };
            SkSTArray<kPreallocSegmentCnt, Segment, true> segments;
            SkPoint fanPt;

            if (!get_segments(*pathPtr, *viewMatrix, &segments, &fanPt, &vertexCount,
                              &indexCount)) {
                continue;
            }

            const GrBuffer* vertexBuffer;
            int firstVertex;

            size_t vertexStride = quadProcessor->getVertexStride();
            QuadVertex* verts = reinterpret_cast<QuadVertex*>(target->makeVertexSpace(
                vertexStride, vertexCount, &vertexBuffer, &firstVertex));

            if (!verts) {
                SkDebugf("Could not allocate vertices\n");
                return;
            }

            const GrBuffer* indexBuffer;
            int firstIndex;

            uint16_t *idxs = target->makeIndexSpace(indexCount, &indexBuffer, &firstIndex);
            if (!idxs) {
                SkDebugf("Could not allocate indices\n");
                return;
            }

            SkSTArray<kPreallocDrawCnt, Draw, true> draws;
            create_vertices(segments, fanPt, &draws, verts, idxs);

            GrMesh mesh;

            for (int j = 0; j < draws.count(); ++j) {
                const Draw& draw = draws[j];
                mesh.initIndexed(kTriangles_GrPrimitiveType, vertexBuffer, indexBuffer,
                                 firstVertex, firstIndex, draw.fVertexCnt, draw.fIndexCnt);
                target->draw(quadProcessor.get(), mesh);
                firstVertex += draw.fVertexCnt;
                firstIndex += draw.fIndexCnt;
            }
        }
    }

GrGLPath::GrGLPath(GrGLGpu* gpu, const SkPath& origSkPath, const GrStrokeInfo& origStroke)
    : INHERITED(gpu, origSkPath, origStroke),
      fPathID(gpu->glPathRendering()->genPaths(1)) {

    if (origSkPath.isEmpty()) {
        InitPathObjectEmptyPath(gpu, fPathID);
        fShouldStroke = false;
        fShouldFill = false;
    } else {
        const SkPath* skPath = &origSkPath;
        SkTLazy<SkPath> tmpPath;
        const GrStrokeInfo* stroke = &origStroke;
        GrStrokeInfo tmpStroke(SkStrokeRec::kFill_InitStyle);

        if (stroke->isDashed()) {
            // Skia stroking and NVPR stroking differ with respect to dashing
            // pattern.
            // Convert a dashing to either a stroke or a fill.
            if (stroke->applyDashToPath(tmpPath.init(), &tmpStroke, *skPath)) {
                skPath = tmpPath.get();
                stroke = &tmpStroke;
            }
        }

        bool didInit = false;
        if (stroke->needToApply() && stroke->getCap() != SkPaint::kButt_Cap) {
            // Skia stroking and NVPR stroking differ with respect to stroking
            // end caps of empty subpaths.
            // Convert stroke to fill if path contains empty subpaths.
            didInit = InitPathObjectPathDataCheckingDegenerates(gpu, fPathID, *skPath);
            if (!didInit) {
                if (!tmpPath.isValid()) {
                    tmpPath.init();
                }
                SkAssertResult(stroke->applyToPath(tmpPath.get(), *skPath));
                skPath = tmpPath.get();
                tmpStroke.setFillStyle();
                stroke = &tmpStroke;
            }
        }

        if (!didInit) {
            InitPathObjectPathData(gpu, fPathID, *skPath);
        }

        fShouldStroke = stroke->needToApply();
        fShouldFill = stroke->isFillStyle() ||
                stroke->getStyle() == SkStrokeRec::kStrokeAndFill_Style;

        fFillType = convert_skpath_filltype(skPath->getFillType());
        fBounds = skPath->getBounds();

        if (fShouldStroke) {
            InitPathObjectStroke(gpu, fPathID, *stroke);

            // FIXME: try to account for stroking, without rasterizing the stroke.
            fBounds.outset(stroke->getWidth(), stroke->getWidth());
        }
    }

    this->registerWithCache();
}

static void draw_path_with_mask_filter(GrContext* context,
                                       GrDrawContext* drawContext,
                                       const GrClip& clip,
                                       GrPaint* paint,
                                       const SkMatrix& viewMatrix,
                                       const SkMaskFilter* maskFilter,
                                       const GrStyle& style,
                                       const SkPath* path,
                                       bool pathIsMutable) {
    SkASSERT(maskFilter);

    SkIRect clipBounds;
    clip.getConservativeBounds(drawContext->width(), drawContext->height(), &clipBounds);
    SkTLazy<SkPath> tmpPath;
    SkStrokeRec::InitStyle fillOrHairline;

    // We just fully apply the style here.
    if (style.applies()) {
        SkScalar scale = GrStyle::MatrixToScaleFactor(viewMatrix);
        if (0 == scale || !style.applyToPath(tmpPath.init(), &fillOrHairline, *path, scale)) {
            return;
        }
        pathIsMutable = true;
        path = tmpPath.get();
    } else if (style.isSimpleHairline()) {
        fillOrHairline = SkStrokeRec::kHairline_InitStyle;
    } else {
        SkASSERT(style.isSimpleFill());
        fillOrHairline = SkStrokeRec::kFill_InitStyle;
    }

    // transform the path into device space
    if (!viewMatrix.isIdentity()) {
        SkPath* result;
        if (pathIsMutable) {
            result = const_cast<SkPath*>(path);
        } else {
            if (!tmpPath.isValid()) {
                tmpPath.init();
            }
            result = tmpPath.get();
        }
        path->transform(viewMatrix, result);
        path = result;
        result->setIsVolatile(true);
        pathIsMutable = true;
    }

    SkRect maskRect;
    if (maskFilter->canFilterMaskGPU(SkRRect::MakeRect(path->getBounds()),
                                     clipBounds,
                                     viewMatrix,
                                     &maskRect)) {
        // This mask will ultimately be drawn as a non-AA rect (see draw_mask).
        // Non-AA rects have a bad habit of snapping arbitrarily. Integerize here
        // so the mask draws in a reproducible manner.
        SkIRect finalIRect;
        maskRect.roundOut(&finalIRect);
        if (clip_bounds_quick_reject(clipBounds, finalIRect)) {
            // clipped out
            return;
        }

        if (maskFilter->directFilterMaskGPU(context->textureProvider(),
                                            drawContext,
                                            paint,
                                            clip,
                                            viewMatrix,
                                            SkStrokeRec(fillOrHairline),
                                            *path)) {
            // the mask filter was able to draw itself directly, so there's nothing
            // left to do.
            return;
        }

        sk_sp<GrTexture> mask(create_mask_GPU(context,
                                              finalIRect,
                                              *path,
                                              fillOrHairline,
                                              paint->isAntiAlias(),
                                              drawContext->numColorSamples()));
        if (mask) {
            GrTexture* filtered;

            if (maskFilter->filterMaskGPU(mask.get(), viewMatrix, finalIRect, &filtered)) {
                // filterMaskGPU gives us ownership of a ref to the result
                SkAutoTUnref<GrTexture> atu(filtered);
                if (draw_mask(drawContext, clip, viewMatrix, finalIRect, paint, filtered)) {
                    // This path is completely drawn
                    return;
                }
            }
        }
    }

    sw_draw_with_mask_filter(drawContext, context->textureProvider(),
                             clip, viewMatrix, *path,
                             maskFilter, clipBounds, paint, fillOrHairline);
}