/* * 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 "GrClipStackClip.h" #include "GrAppliedClip.h" #include "GrContextPriv.h" #include "GrDrawingManager.h" #include "GrDrawContextPriv.h" #include "GrFixedClip.h" #include "GrGpuResourcePriv.h" #include "GrRenderTargetPriv.h" #include "GrStencilAttachment.h" #include "GrSWMaskHelper.h" #include "effects/GrConvexPolyEffect.h" #include "effects/GrRRectEffect.h" #include "effects/GrTextureDomain.h" typedef SkClipStack::Element Element; typedef GrReducedClip::InitialState InitialState; typedef GrReducedClip::ElementList ElementList; static const int kMaxAnalyticElements = 4; bool GrClipStackClip::quickContains(const SkRect& rect) const { if (!fStack || fStack->isWideOpen()) { return true; } return fStack->quickContains(rect.makeOffset(SkIntToScalar(fOrigin.x()), SkIntToScalar(fOrigin.y()))); } bool GrClipStackClip::quickContains(const SkRRect& rrect) const { if (!fStack || fStack->isWideOpen()) { return true; } return fStack->quickContains(rrect.makeOffset(SkIntToScalar(fOrigin.fX), SkIntToScalar(fOrigin.fY))); } bool GrClipStackClip::isRRect(const SkRect& origRTBounds, SkRRect* rr, bool* aa) const { if (!fStack) { return false; } const SkRect* rtBounds = &origRTBounds; SkRect tempRTBounds; bool origin = fOrigin.fX || fOrigin.fY; if (origin) { tempRTBounds = origRTBounds; tempRTBounds.offset(SkIntToScalar(fOrigin.fX), SkIntToScalar(fOrigin.fY)); rtBounds = &tempRTBounds; } if (fStack->isRRect(*rtBounds, rr, aa)) { if (origin) { rr->offset(-SkIntToScalar(fOrigin.fX), -SkIntToScalar(fOrigin.fY)); } return true; } return false; } void GrClipStackClip::getConservativeBounds(int width, int height, SkIRect* devResult, bool* isIntersectionOfRects) const { if (!fStack) { devResult->setXYWH(0, 0, width, height); if (isIntersectionOfRects) { *isIntersectionOfRects = true; } return; } SkRect devBounds; fStack->getConservativeBounds(-fOrigin.x(), -fOrigin.y(), width, height, &devBounds, isIntersectionOfRects); devBounds.roundOut(devResult); } //////////////////////////////////////////////////////////////////////////////// // set up the draw state to enable the aa clipping mask. Besides setting up the // stage matrix this also alters the vertex layout static sk_sp create_fp_for_mask(GrTexture* result, const SkIRect &devBound) { SkMatrix mat; // We use device coords to compute the texture coordinates. We set our matrix to be a // translation to the devBound, and then a scaling matrix to normalized coords. mat.setIDiv(result->width(), result->height()); mat.preTranslate(SkIntToScalar(-devBound.fLeft), SkIntToScalar(-devBound.fTop)); SkIRect domainTexels = SkIRect::MakeWH(devBound.width(), devBound.height()); return sk_sp(GrTextureDomainEffect::Make( result, nullptr, mat, GrTextureDomain::MakeTexelDomain(result, domainTexels), GrTextureDomain::kDecal_Mode, GrTextureParams::kNone_FilterMode, kDevice_GrCoordSet)); } // Does the path in 'element' require SW rendering? If so, return true (and, // optionally, set 'prOut' to NULL. If not, return false (and, optionally, set // 'prOut' to the non-SW path renderer that will do the job). bool GrClipStackClip::PathNeedsSWRenderer(GrContext* context, bool hasUserStencilSettings, const GrDrawContext* drawContext, const SkMatrix& viewMatrix, const Element* element, GrPathRenderer** prOut, bool needsStencil) { if (Element::kRect_Type == element->getType()) { // rects can always be drawn directly w/o using the software path // TODO: skip rrects once we're drawing them directly. if (prOut) { *prOut = nullptr; } return false; } else { // We shouldn't get here with an empty clip element. SkASSERT(Element::kEmpty_Type != element->getType()); // the gpu alpha mask will draw the inverse paths as non-inverse to a temp buffer SkPath path; element->asPath(&path); if (path.isInverseFillType()) { path.toggleInverseFillType(); } GrPathRendererChain::DrawType type; if (needsStencil) { type = element->isAA() ? GrPathRendererChain::kStencilAndColorAntiAlias_DrawType : GrPathRendererChain::kStencilAndColor_DrawType; } else { type = element->isAA() ? GrPathRendererChain::kColorAntiAlias_DrawType : GrPathRendererChain::kColor_DrawType; } GrShape shape(path, GrStyle::SimpleFill()); GrPathRenderer::CanDrawPathArgs canDrawArgs; canDrawArgs.fShaderCaps = context->caps()->shaderCaps(); canDrawArgs.fViewMatrix = &viewMatrix; canDrawArgs.fShape = &shape; canDrawArgs.fAntiAlias = element->isAA(); canDrawArgs.fHasUserStencilSettings = hasUserStencilSettings; canDrawArgs.fIsStencilBufferMSAA = drawContext->isStencilBufferMultisampled(); // the 'false' parameter disallows use of the SW path renderer GrPathRenderer* pr = context->contextPriv().drawingManager()->getPathRenderer(canDrawArgs, false, type); if (prOut) { *prOut = pr; } return SkToBool(!pr); } } /* * This method traverses the clip stack to see if the GrSoftwarePathRenderer * will be used on any element. If so, it returns true to indicate that the * entire clip should be rendered in SW and then uploaded en masse to the gpu. */ bool GrClipStackClip::UseSWOnlyPath(GrContext* context, bool hasUserStencilSettings, const GrDrawContext* drawContext, const GrReducedClip& reducedClip) { // TODO: generalize this function so that when // a clip gets complex enough it can just be done in SW regardless // of whether it would invoke the GrSoftwarePathRenderer. // Set the matrix so that rendered clip elements are transformed to mask space from clip // space. SkMatrix translate; translate.setTranslate(SkIntToScalar(-reducedClip.left()), SkIntToScalar(-reducedClip.top())); for (ElementList::Iter iter(reducedClip.elements()); iter.get(); iter.next()) { const Element* element = iter.get(); SkRegion::Op op = element->getOp(); bool invert = element->isInverseFilled(); bool needsStencil = invert || SkRegion::kIntersect_Op == op || SkRegion::kReverseDifference_Op == op; if (PathNeedsSWRenderer(context, hasUserStencilSettings, drawContext, translate, element, nullptr, needsStencil)) { return true; } } return false; } static bool get_analytic_clip_processor(const ElementList& elements, bool abortIfAA, const SkVector& clipToRTOffset, const SkRect& drawBounds, sk_sp* resultFP) { SkRect boundsInClipSpace; boundsInClipSpace = drawBounds.makeOffset(-clipToRTOffset.fX, -clipToRTOffset.fY); SkASSERT(elements.count() <= kMaxAnalyticElements); SkSTArray> fps; ElementList::Iter iter(elements); while (iter.get()) { SkRegion::Op op = iter.get()->getOp(); bool invert; bool skip = false; switch (op) { case SkRegion::kReplace_Op: SkASSERT(iter.get() == elements.head()); // Fallthrough, handled same as intersect. case SkRegion::kIntersect_Op: invert = false; if (iter.get()->contains(boundsInClipSpace)) { skip = true; } break; case SkRegion::kDifference_Op: invert = true; // We don't currently have a cheap test for whether a rect is fully outside an // element's primitive, so don't attempt to set skip. break; default: return false; } if (!skip) { GrPrimitiveEdgeType edgeType; if (iter.get()->isAA()) { if (abortIfAA) { return false; } edgeType = invert ? kInverseFillAA_GrProcessorEdgeType : kFillAA_GrProcessorEdgeType; } else { edgeType = invert ? kInverseFillBW_GrProcessorEdgeType : kFillBW_GrProcessorEdgeType; } switch (iter.get()->getType()) { case SkClipStack::Element::kPath_Type: fps.emplace_back(GrConvexPolyEffect::Make(edgeType, iter.get()->getPath(), &clipToRTOffset)); break; case SkClipStack::Element::kRRect_Type: { SkRRect rrect = iter.get()->getRRect(); rrect.offset(clipToRTOffset.fX, clipToRTOffset.fY); fps.emplace_back(GrRRectEffect::Make(edgeType, rrect)); break; } case SkClipStack::Element::kRect_Type: { SkRect rect = iter.get()->getRect(); rect.offset(clipToRTOffset.fX, clipToRTOffset.fY); fps.emplace_back(GrConvexPolyEffect::Make(edgeType, rect)); break; } default: break; } if (!fps.back()) { return false; } } iter.next(); } *resultFP = nullptr; if (fps.count()) { *resultFP = GrFragmentProcessor::RunInSeries(fps.begin(), fps.count()); } return true; } //////////////////////////////////////////////////////////////////////////////// // sort out what kind of clip mask needs to be created: alpha, stencil, // scissor, or entirely software bool GrClipStackClip::apply(GrContext* context, GrDrawContext* drawContext, bool useHWAA, bool hasUserStencilSettings, GrAppliedClip* out) const { if (!fStack || fStack->isWideOpen()) { return true; } SkRect devBounds = SkRect::MakeIWH(drawContext->width(), drawContext->height()); if (!devBounds.intersect(out->clippedDrawBounds())) { return false; } const SkScalar clipX = SkIntToScalar(fOrigin.x()), clipY = SkIntToScalar(fOrigin.y()); SkRect clipSpaceDevBounds = devBounds.makeOffset(clipX, clipY); const GrReducedClip reducedClip(*fStack, clipSpaceDevBounds); if (reducedClip.hasIBounds() && !GrClip::IsInsideClip(reducedClip.ibounds(), clipSpaceDevBounds)) { SkIRect scissorSpaceIBounds(reducedClip.ibounds()); scissorSpaceIBounds.offset(-fOrigin); out->addScissor(scissorSpaceIBounds); } if (reducedClip.elements().isEmpty()) { return InitialState::kAllIn == reducedClip.initialState(); } SkASSERT(reducedClip.hasIBounds()); // Attempt to implement difference clip rects with window rectangles. This will eventually // become more comprehensive. if (drawContext->accessRenderTarget()->renderTargetPriv().supportsWindowRectangles() && 1 == reducedClip.elements().count() && !reducedClip.requiresAA() && InitialState::kAllIn == reducedClip.initialState()) { const Element* element = reducedClip.elements().head(); SkRegion::Op op = element->getOp(); if (Element::kRect_Type == element->getType() && (SkRegion::kDifference_Op == op || SkRegion::kXOR_Op == op)) { SkIRect window; element->getRect().round(&window); window.offset(-fOrigin); out->addWindowRectangle(window); return true; } } // 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 (reducedClip.elements().count() <= kMaxAnalyticElements) { // When there are multiple samples we want to do per-sample clipping, not compute a // fractional pixel coverage. bool disallowAnalyticAA = drawContext->isStencilBufferMultisampled(); if (disallowAnalyticAA && !drawContext->numColorSamples()) { // With a single color sample, any coverage info is lost from color once it hits the // color buffer anyway, so we may as well use coverage AA if nothing else in the pipe // is multisampled. disallowAnalyticAA = useHWAA || hasUserStencilSettings; } sk_sp clipFP; if (reducedClip.requiresAA() && get_analytic_clip_processor(reducedClip.elements(), disallowAnalyticAA, {-clipX, -clipY}, devBounds, &clipFP)) { out->addCoverageFP(std::move(clipFP)); return true; } } // If the stencil buffer is multisampled we can use it to do everything. if (!drawContext->isStencilBufferMultisampled() && reducedClip.requiresAA()) { sk_sp result; if (UseSWOnlyPath(context, hasUserStencilSettings, drawContext, reducedClip)) { // The clip geometry is complex enough that it will be more efficient to create it // entirely in software result = CreateSoftwareClipMask(context->textureProvider(), reducedClip); } else { result = CreateAlphaClipMask(context, reducedClip); // If createAlphaClipMask fails it means UseSWOnlyPath has a bug SkASSERT(result); } if (result) { // The mask's top left coord should be pinned to the rounded-out top left corner of // clipSpace bounds. We determine the mask's position WRT to the render target here. SkIRect rtSpaceMaskBounds = reducedClip.ibounds(); rtSpaceMaskBounds.offset(-fOrigin); out->addCoverageFP(create_fp_for_mask(result.get(), rtSpaceMaskBounds)); return true; } // if alpha clip mask creation fails fall through to the non-AA code paths } // use the stencil clip if we can't represent the clip as a rectangle. // TODO: these need to be swapped over to using a StencilAttachmentProxy GrStencilAttachment* stencilAttachment = context->resourceProvider()->attachStencilAttachment(drawContext->accessRenderTarget()); if (nullptr == stencilAttachment) { SkDebugf("WARNING: failed to attach stencil buffer for clip mask. Clip will be ignored.\n"); return true; } if (stencilAttachment->mustRenderClip(reducedClip.elementsGenID(), reducedClip.ibounds(), fOrigin)) { reducedClip.drawStencilClipMask(context, drawContext, fOrigin); stencilAttachment->setLastClip(reducedClip.elementsGenID(), reducedClip.ibounds(), fOrigin); } out->addStencilClip(); return true; } //////////////////////////////////////////////////////////////////////////////// // Create a 8-bit clip mask in alpha static void GetClipMaskKey(int32_t clipGenID, const SkIRect& bounds, GrUniqueKey* key) { static const GrUniqueKey::Domain kDomain = GrUniqueKey::GenerateDomain(); GrUniqueKey::Builder builder(key, kDomain, 3); builder[0] = clipGenID; builder[1] = SkToU16(bounds.fLeft) | (SkToU16(bounds.fRight) << 16); builder[2] = SkToU16(bounds.fTop) | (SkToU16(bounds.fBottom) << 16); } sk_sp GrClipStackClip::CreateAlphaClipMask(GrContext* context, const GrReducedClip& reducedClip) { GrResourceProvider* resourceProvider = context->resourceProvider(); GrUniqueKey key; GetClipMaskKey(reducedClip.elementsGenID(), reducedClip.ibounds(), &key); if (GrTexture* texture = resourceProvider->findAndRefTextureByUniqueKey(key)) { return sk_sp(texture); } // There's no texture in the cache. Let's try to allocate it then. GrPixelConfig config = kRGBA_8888_GrPixelConfig; if (context->caps()->isConfigRenderable(kAlpha_8_GrPixelConfig, false)) { config = kAlpha_8_GrPixelConfig; } sk_sp dc(context->makeDrawContext(SkBackingFit::kApprox, reducedClip.width(), reducedClip.height(), config, nullptr)); if (!dc) { return nullptr; } if (!reducedClip.drawAlphaClipMask(dc.get())) { return nullptr; } sk_sp texture(dc->asTexture()); SkASSERT(texture); texture->resourcePriv().setUniqueKey(key); return texture; } sk_sp GrClipStackClip::CreateSoftwareClipMask(GrTextureProvider* texProvider, const GrReducedClip& reducedClip) { GrUniqueKey key; GetClipMaskKey(reducedClip.elementsGenID(), reducedClip.ibounds(), &key); if (GrTexture* texture = texProvider->findAndRefTextureByUniqueKey(key)) { return sk_sp(texture); } // The mask texture may be larger than necessary. We round out the clip space bounds and pin // the top left corner of the resulting rect to the top left of the texture. SkIRect maskSpaceIBounds = SkIRect::MakeWH(reducedClip.width(), reducedClip.height()); GrSWMaskHelper helper(texProvider); // Set the matrix so that rendered clip elements are transformed to mask space from clip // space. SkMatrix translate; translate.setTranslate(SkIntToScalar(-reducedClip.left()), SkIntToScalar(-reducedClip.top())); helper.init(maskSpaceIBounds, &translate); helper.clear(InitialState::kAllIn == reducedClip.initialState() ? 0xFF : 0x00); for (ElementList::Iter iter(reducedClip.elements()); iter.get(); iter.next()) { const Element* element = iter.get(); SkRegion::Op op = element->getOp(); if (SkRegion::kIntersect_Op == op || SkRegion::kReverseDifference_Op == op) { // Intersect and reverse difference require modifying pixels outside of the geometry // that is being "drawn". In both cases we erase all the pixels outside of the geometry // but leave the pixels inside the geometry alone. For reverse difference we invert all // the pixels before clearing the ones outside the geometry. if (SkRegion::kReverseDifference_Op == op) { SkRect temp = SkRect::Make(reducedClip.ibounds()); // invert the entire scene helper.drawRect(temp, SkRegion::kXOR_Op, false, 0xFF); } SkPath clipPath; element->asPath(&clipPath); clipPath.toggleInverseFillType(); GrShape shape(clipPath, GrStyle::SimpleFill()); helper.drawShape(shape, SkRegion::kReplace_Op, element->isAA(), 0x00); continue; } // The other ops (union, xor, diff) only affect pixels inside // the geometry so they can just be drawn normally if (Element::kRect_Type == element->getType()) { helper.drawRect(element->getRect(), op, element->isAA(), 0xFF); } else { SkPath path; element->asPath(&path); GrShape shape(path, GrStyle::SimpleFill()); helper.drawShape(shape, op, element->isAA(), 0xFF); } } // Allocate clip mask texture GrSurfaceDesc desc; desc.fWidth = reducedClip.width(); desc.fHeight = reducedClip.height(); desc.fConfig = kAlpha_8_GrPixelConfig; sk_sp result(texProvider->createApproxTexture(desc)); if (!result) { return nullptr; } result->resourcePriv().setUniqueKey(key); helper.toTexture(result.get()); return result; }