C++ SkPath::isVolatile方法代码示例

bool GrAADistanceFieldPathRenderer::canDrawPath(const GrDrawTarget* target,
                                                const GrPipelineBuilder* pipelineBuilder,
                                                const SkMatrix& viewMatrix,
                                                const SkPath& path,
                                                const GrStrokeInfo& stroke,
                                                bool antiAlias) const {
    
    // TODO: Support inverse fill
    // TODO: Support strokes
    if (!target->caps()->shaderCaps()->shaderDerivativeSupport() || !antiAlias 
        || path.isInverseFillType() || path.isVolatile() || !stroke.isFillStyle()) {
        return false;
    }

    // currently don't support perspective
    if (viewMatrix.hasPerspective()) {
        return false;
    }
    
    // only support paths smaller than 64x64, scaled to less than 256x256
    // the goal is to accelerate rendering of lots of small paths that may be scaling
    SkScalar maxScale = viewMatrix.getMaxScale();
    const SkRect& bounds = path.getBounds();
    SkScalar maxDim = SkMaxScalar(bounds.width(), bounds.height());
    return maxDim < 64.f && maxDim * maxScale < 256.f;
}

void GrBlurUtils::drawPathWithMaskFilter(GrContext* context,
                                         GrDrawContext* drawContext,
                                         const GrClip& clip,
                                         const SkPath& origPath,
                                         const SkPaint& paint,
                                         const SkMatrix& origViewMatrix,
                                         const SkMatrix* prePathMatrix,
                                         const SkIRect& clipBounds,
                                         bool pathIsMutable) {
    SkASSERT(!pathIsMutable || origPath.isVolatile());

    GrStyle style(paint);
    // If we have a prematrix, apply it to the path, optimizing for the case
    // where the original path can in fact be modified in place (even though
    // its parameter type is const).

    const SkPath* path = &origPath;
    SkTLazy<SkPath> tmpPath;

    SkMatrix viewMatrix = origViewMatrix;

    if (prePathMatrix) {
        // Styling, blurs, and shading are supposed to be applied *after* the prePathMatrix.
        if (!paint.getMaskFilter() && !paint.getShader() && !style.applies()) {
            viewMatrix.preConcat(*prePathMatrix);
        } else {
            SkPath* result = pathIsMutable ? const_cast<SkPath*>(path) : tmpPath.init();
            pathIsMutable = true;
            path->transform(*prePathMatrix, result);
            path = result;
            result->setIsVolatile(true);
        }
    }
    // at this point we're done with prePathMatrix
    SkDEBUGCODE(prePathMatrix = (const SkMatrix*)0x50FF8001;)

void GrBlurUtils::drawPathWithMaskFilter(GrContext* context,
                                         GrDrawContext* drawContext,
                                         const GrClip& clip,
                                         const SkPath& origSrcPath,
                                         const SkPaint& paint,
                                         const SkMatrix& origViewMatrix,
                                         const SkMatrix* prePathMatrix,
                                         const SkIRect& clipBounds,
                                         bool pathIsMutable) {
    SkASSERT(!pathIsMutable || origSrcPath.isVolatile());

    GrStrokeInfo strokeInfo(paint);
    // comment out the line below to determine if it is the reason that the chrome mac perf bot
    // has begun crashing
    // strokeInfo.setResScale(SkDraw::ComputeResScaleForStroking(origViewMatrix));

    // If we have a prematrix, apply it to the path, optimizing for the case
    // where the original path can in fact be modified in place (even though
    // its parameter type is const).
    SkPath* pathPtr = const_cast<SkPath*>(&origSrcPath);
    SkTLazy<SkPath> tmpPath;
    SkTLazy<SkPath> effectPath;
    SkPathEffect* pathEffect = paint.getPathEffect();

    SkMatrix viewMatrix = origViewMatrix;

    if (prePathMatrix) {
        // stroking, path effects, and blurs are supposed to be applied *after* the prePathMatrix.
        // The pre-path-matrix also should not affect shading.
        if (!paint.getMaskFilter() && !pathEffect && !paint.getShader() &&
            (strokeInfo.isFillStyle() || strokeInfo.isHairlineStyle())) {
            viewMatrix.preConcat(*prePathMatrix);
        } else {
            SkPath* result = pathPtr;

            if (!pathIsMutable) {
                result = tmpPath.init();
                result->setIsVolatile(true);
                pathIsMutable = true;
            }
            // should I push prePathMatrix on our MV stack temporarily, instead
            // of applying it here? See SkDraw.cpp
            pathPtr->transform(*prePathMatrix, result);
            pathPtr = result;
        }
    }
    // at this point we're done with prePathMatrix
    SkDEBUGCODE(prePathMatrix = (const SkMatrix*)0x50FF8001;)

void GrPath::ComputeKey(const SkPath& path, const GrStrokeInfo& stroke, GrUniqueKey* key,
                        bool* outIsVolatile) {
    if (compute_key_for_line_path(path, stroke, key)) {
        *outIsVolatile = false;
        return;
    }

    if (compute_key_for_oval_path(path, stroke, key)) {
        *outIsVolatile = false;
        return;
    }

    if (compute_key_for_simple_path(path, stroke, key)) {
        *outIsVolatile = false;
        return;
    }

    compute_key_for_general_path(path, stroke, key);
    *outIsVolatile = path.isVolatile();
}