C++ GrPipelineBuilder::clip方法代码示例

bool GrDrawTarget::setupDstReadIfNecessary(const GrPipelineBuilder& pipelineBuilder,
                                           const GrProcOptInfo& colorPOI,
                                           const GrProcOptInfo& coveragePOI,
                                           GrDeviceCoordTexture* dstCopy,
                                           const SkRect* drawBounds) {
    if (!pipelineBuilder.willXPNeedDstCopy(*this->caps(), colorPOI, coveragePOI)) {
        return true;
    }
    SkIRect copyRect;
    GrRenderTarget* rt = pipelineBuilder.getRenderTarget();
    pipelineBuilder.clip().getConservativeBounds(rt, &copyRect);

    if (drawBounds) {
        SkIRect drawIBounds;
        drawBounds->roundOut(&drawIBounds);
        if (!copyRect.intersect(drawIBounds)) {
#ifdef SK_DEBUG
            SkDebugf("Missed an early reject. Bailing on draw from setupDstReadIfNecessary.\n");
#endif
            return false;
        }
    } else {
#ifdef SK_DEBUG
        //SkDebugf("No dev bounds when dst copy is made.\n");
#endif
    }

    // MSAA consideration: When there is support for reading MSAA samples in the shader we could
    // have per-sample dst values by making the copy multisampled.
    GrSurfaceDesc desc;
    this->initCopySurfaceDstDesc(rt, &desc);
    desc.fWidth = copyRect.width();
    desc.fHeight = copyRect.height();

    SkAutoTUnref<GrTexture> copy(
        fContext->refScratchTexture(desc, GrContext::kApprox_ScratchTexMatch));

    if (!copy) {
        SkDebugf("Failed to create temporary copy of destination texture.\n");
        return false;
    }
    SkIPoint dstPoint = {0, 0};
    if (this->copySurface(copy, rt, copyRect, dstPoint)) {
        dstCopy->setTexture(copy);
        dstCopy->setOffset(copyRect.fLeft, copyRect.fTop);
        return true;
    } else {
        return false;
    }
}

bool GrDrawTarget::setupDstReadIfNecessary(const GrPipelineBuilder& pipelineBuilder,
                                           const GrPipelineOptimizations& optimizations,
                                           GrXferProcessor::DstTexture* dstTexture,
                                           const SkRect& batchBounds) {
    SkRect bounds = batchBounds;
    bounds.outset(0.5f, 0.5f);

    if (!pipelineBuilder.willXPNeedDstTexture(*this->caps(), optimizations)) {
        return true;
    }

    GrRenderTarget* rt = pipelineBuilder.getRenderTarget();

    if (this->caps()->textureBarrierSupport()) {
        if (GrTexture* rtTex = rt->asTexture()) {
            // The render target is a texture, so we can read from it directly in the shader. The XP
            // will be responsible to detect this situation and request a texture barrier.
            dstTexture->setTexture(rtTex);
            dstTexture->setOffset(0, 0);
            return true;
        }
    }

    SkIRect copyRect;
    pipelineBuilder.clip().getConservativeBounds(rt->width(), rt->height(), &copyRect);

    SkIRect drawIBounds;
    bounds.roundOut(&drawIBounds);
    if (!copyRect.intersect(drawIBounds)) {
#ifdef SK_DEBUG
        GrCapsDebugf(this->caps(), "Missed an early reject. "
                                   "Bailing on draw from setupDstReadIfNecessary.\n");
#endif
        return false;
    }

    // MSAA consideration: When there is support for reading MSAA samples in the shader we could
    // have per-sample dst values by making the copy multisampled.
    GrSurfaceDesc desc;
    if (!fGpu->initCopySurfaceDstDesc(rt, &desc)) {
        desc.fOrigin = kDefault_GrSurfaceOrigin;
        desc.fFlags = kRenderTarget_GrSurfaceFlag;
        desc.fConfig = rt->config();
    }

    desc.fWidth = copyRect.width();
    desc.fHeight = copyRect.height();

    static const uint32_t kFlags = 0;
    SkAutoTUnref<GrTexture> copy(fResourceProvider->createApproxTexture(desc, kFlags));

    if (!copy) {
        SkDebugf("Failed to create temporary copy of destination texture.\n");
        return false;
    }
    SkIPoint dstPoint = {0, 0};
    this->copySurface(copy, rt, copyRect, dstPoint);
    dstTexture->setTexture(copy);
    dstTexture->setOffset(copyRect.fLeft, copyRect.fTop);
    return true;
}

////////////////////////////////////////////////////////////////////////////////
// sort out what kind of clip mask needs to be created: alpha, stencil,
// scissor, or entirely software
bool GrClipMaskManager::setupClipping(const GrPipelineBuilder& pipelineBuilder,
                                      GrPipelineBuilder::AutoRestoreStencil* ars,
                                      GrScissorState* scissorState,
                                      const SkRect* devBounds,
                                      GrAppliedClip* out) {
    if (kRespectClip_StencilClipMode == fClipMode) {
        fClipMode = kIgnoreClip_StencilClipMode;
    }

    GrReducedClip::ElementList elements(16);
    int32_t genID = 0;
    GrReducedClip::InitialState initialState = GrReducedClip::kAllIn_InitialState;
    SkIRect clipSpaceIBounds;
    bool requiresAA = false;
    GrRenderTarget* rt = pipelineBuilder.getRenderTarget();

    // GrDrawTarget should have filtered this for us
    SkASSERT(rt);

    SkIRect clipSpaceRTIBounds = SkIRect::MakeWH(rt->width(), rt->height());
    const GrClip& clip = pipelineBuilder.clip();
    if (clip.isWideOpen(clipSpaceRTIBounds)) {
        this->setPipelineBuilderStencil(pipelineBuilder, ars);
        return true;
    }

    // The clip mask manager always draws with a single IRect so we special case that logic here
    // Image filters just use a rect, so we also special case that logic
    switch (clip.clipType()) {
        case GrClip::kWideOpen_ClipType:
            SkFAIL("Should have caught this with clip.isWideOpen()");
            return true;
        case GrClip::kIRect_ClipType: {
            SkIRect scissor = clip.irect();
            if (scissor.intersect(clipSpaceRTIBounds)) {
                scissorState->set(scissor);
                this->setPipelineBuilderStencil(pipelineBuilder, ars);
                return true;
            }
            return false;
        }
        case GrClip::kClipStack_ClipType: {
            clipSpaceRTIBounds.offset(clip.origin());
            GrReducedClip::ReduceClipStack(*clip.clipStack(),
                                            clipSpaceRTIBounds,
                                            &elements,
                                            &genID,
                                            &initialState,
                                            &clipSpaceIBounds,
                                            &requiresAA);
            if (elements.isEmpty()) {
                if (GrReducedClip::kAllIn_InitialState == initialState) {
                    if (clipSpaceIBounds == clipSpaceRTIBounds) {
                        this->setPipelineBuilderStencil(pipelineBuilder, ars);
                        return true;
                    }
                } else {
                    return false;
                }
            }
        } break;
    }

    // An element count of 4 was chosen because of the common pattern in Blink of:
    //   isect RR
    //   diff  RR
    //   isect convex_poly
    //   isect convex_poly
    // when drawing rounded div borders. This could probably be tuned based on a
    // configuration's relative costs of switching RTs to generate a mask vs
    // longer shaders.
    if (elements.count() <= kMaxAnalyticElements) {
        SkVector clipToRTOffset = { SkIntToScalar(-clip.origin().fX),
                                    SkIntToScalar(-clip.origin().fY) };
        // When there are multiple color samples we want to do per-sample clipping, not compute
        // a fractional pixel coverage.
        bool disallowAnalyticAA = pipelineBuilder.getRenderTarget()->isUnifiedMultisampled();
        const GrFragmentProcessor* clipFP = nullptr;
        if (elements.isEmpty() ||
            (requiresAA && !disallowAnalyticAA &&
             SkToBool(clipFP = this->getAnalyticClipProcessor(elements, clipToRTOffset, devBounds)))) {
            SkIRect scissorSpaceIBounds(clipSpaceIBounds);
            scissorSpaceIBounds.offset(-clip.origin());
            if (nullptr == devBounds ||
                !SkRect::Make(scissorSpaceIBounds).contains(*devBounds)) {
                scissorState->set(scissorSpaceIBounds);
            }
            this->setPipelineBuilderStencil(pipelineBuilder, ars);
            out->fClipCoverageFP.reset(clipFP);
            return true;
        }
    }

    // If MSAA is enabled we can do everything in the stencil buffer.
    if (0 == rt->numStencilSamples() && requiresAA) {
        SkAutoTUnref<GrTexture> result;

//.........这里部分代码省略.........