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/*
* Copyright 2012 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "GrClipMaskManager.h"
#include "GrCaps.h"
#include "GrDrawingManager.h"
#include "GrDrawContextPriv.h"
#include "GrGpuResourcePriv.h"
#include "GrPaint.h"
#include "GrPathRenderer.h"
#include "GrRenderTarget.h"
#include "GrRenderTargetPriv.h"
#include "GrResourceProvider.h"
#include "GrStencilAttachment.h"
#include "GrSWMaskHelper.h"
#include "SkRasterClip.h"
#include "SkTLazy.h"
#include "batches/GrRectBatchFactory.h"
#include "effects/GrConvexPolyEffect.h"
#include "effects/GrPorterDuffXferProcessor.h"
#include "effects/GrRRectEffect.h"
#include "effects/GrTextureDomain.h"
typedef SkClipStack::Element Element;
static const int kMaxAnalyticElements = 4;
////////////////////////////////////////////////////////////////////////////////
// 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<GrFragmentProcessor> 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<GrFragmentProcessor>(GrTextureDomainEffect::Make(
result,
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 GrClipMaskManager::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;
}
GrPathRenderer::CanDrawPathArgs canDrawArgs;
canDrawArgs.fShaderCaps = context->caps()->shaderCaps();
canDrawArgs.fViewMatrix = &viewMatrix;
canDrawArgs.fPath = &path;
canDrawArgs.fStyle = &GrStyle::SimpleFill();
canDrawArgs.fAntiAlias = element->isAA();
canDrawArgs.fHasUserStencilSettings = hasUserStencilSettings;
canDrawArgs.fIsStencilBufferMSAA = drawContext->isStencilBufferMultisampled();
// the 'false' parameter disallows use of the SW path renderer
GrPathRenderer* pr = context->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 GrClipMaskManager::UseSWOnlyPath(GrContext* context,
const GrPipelineBuilder& pipelineBuilder,
const GrDrawContext* drawContext,
const SkVector& clipToMaskOffset,
const GrReducedClip::ElementList& elements) {
// 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.
const SkMatrix translate = SkMatrix::MakeTrans(clipToMaskOffset.fX, clipToMaskOffset.fY);
for (GrReducedClip::ElementList::Iter iter(elements.headIter()); 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, pipelineBuilder.hasUserStencilSettings(),
drawContext, translate, element, nullptr, needsStencil)) {
return true;
}
}
return false;
}
static bool get_analytic_clip_processor(const GrReducedClip::ElementList& elements,
bool abortIfAA,
SkVector& clipToRTOffset,
const SkRect* drawBounds,
sk_sp<GrFragmentProcessor>* resultFP) {
SkRect boundsInClipSpace;
if (drawBounds) {
boundsInClipSpace = *drawBounds;
boundsInClipSpace.offset(-clipToRTOffset.fX, -clipToRTOffset.fY);
}
SkASSERT(elements.count() <= kMaxAnalyticElements);
SkSTArray<kMaxAnalyticElements, sk_sp<GrFragmentProcessor>> fps;
GrReducedClip::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 (drawBounds && 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 GrClipMaskManager::SetupClipping(GrContext* context,
const GrPipelineBuilder& pipelineBuilder,
GrDrawContext* drawContext,
const GrClipStackClip& clip,
const SkRect* devBounds,
GrAppliedClip* out) {
if (!clip.clipStack() || clip.clipStack()->isWideOpen()) {
return true;
}
GrReducedClip::ElementList elements;
int32_t genID = 0;
GrReducedClip::InitialState initialState = GrReducedClip::kAllIn_InitialState;
SkIRect clipSpaceIBounds;
bool requiresAA = false;
SkIRect clipSpaceRTIBounds = SkIRect::MakeWH(drawContext->width(), drawContext->height());
clipSpaceRTIBounds.offset(clip.origin());
SkIRect clipSpaceReduceQueryBounds;
#define DISABLE_DEV_BOUNDS_FOR_CLIP_REDUCTION 0
if (devBounds && !DISABLE_DEV_BOUNDS_FOR_CLIP_REDUCTION) {
SkIRect devIBounds = devBounds->roundOut();
devIBounds.offset(clip.origin());
if (!clipSpaceReduceQueryBounds.intersect(clipSpaceRTIBounds, devIBounds)) {
return false;
}
} else {
clipSpaceReduceQueryBounds = clipSpaceRTIBounds;
}
GrReducedClip::ReduceClipStack(*clip.clipStack(),
clipSpaceReduceQueryBounds,
&elements,
&genID,
&initialState,
&clipSpaceIBounds,
&requiresAA);
if (elements.isEmpty()) {
if (GrReducedClip::kAllIn_InitialState == initialState) {
if (clipSpaceIBounds == clipSpaceRTIBounds) {
return true;
}
} else {
return false;
}
}
// 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 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 = pipelineBuilder.isHWAntialias() ||
pipelineBuilder.hasUserStencilSettings();
}
sk_sp<GrFragmentProcessor> clipFP;
if (elements.isEmpty() ||
(requiresAA &&
get_analytic_clip_processor(elements, disallowAnalyticAA, clipToRTOffset, devBounds,
&clipFP))) {
SkIRect scissorSpaceIBounds(clipSpaceIBounds);
scissorSpaceIBounds.offset(-clip.origin());
if (!devBounds || !SkRect::Make(scissorSpaceIBounds).contains(*devBounds)) {
out->makeScissoredFPBased(std::move(clipFP), scissorSpaceIBounds);
return true;
}
out->makeFPBased(std::move(clipFP));
return true;
}
}
// If the stencil buffer is multisampled we can use it to do everything.
if (!drawContext->isStencilBufferMultisampled() && requiresAA) {
sk_sp<GrTexture> result;
// The top-left of the mask corresponds to the top-left corner of the bounds.
SkVector clipToMaskOffset = {
SkIntToScalar(-clipSpaceIBounds.fLeft),
SkIntToScalar(-clipSpaceIBounds.fTop)
};
if (UseSWOnlyPath(context, pipelineBuilder, drawContext,
clipToMaskOffset, elements)) {
// The clip geometry is complex enough that it will be more efficient to create it
// entirely in software
result = CreateSoftwareClipMask(context->textureProvider(),
genID,
initialState,
elements,
clipToMaskOffset,
clipSpaceIBounds);
} else {
result = CreateAlphaClipMask(context,
genID,
initialState,
elements,
clipToMaskOffset,
clipSpaceIBounds);
// 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 = clipSpaceIBounds;
rtSpaceMaskBounds.offset(-clip.origin());
out->makeFPBased(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.
SkIPoint clipSpaceToStencilSpaceOffset = -clip.origin();
CreateStencilClipMask(context,
drawContext,
genID,
initialState,
elements,
clipSpaceIBounds,
clipSpaceToStencilSpaceOffset);
// This must occur after createStencilClipMask. That function may change the scissor. Also, it
// only guarantees that the stencil mask is correct within the bounds it was passed, so we must
// use both stencil and scissor test to the bounds for the final draw.
SkIRect scissorSpaceIBounds(clipSpaceIBounds);
scissorSpaceIBounds.offset(clipSpaceToStencilSpaceOffset);
out->makeScissoredStencil(true, scissorSpaceIBounds);
return true;
}
static bool stencil_element(GrDrawContext* dc,
const GrFixedClip& clip,
const GrUserStencilSettings* ss,
const SkMatrix& viewMatrix,
const SkClipStack::Element* element) {
// TODO: Draw rrects directly here.
switch (element->getType()) {
case Element::kEmpty_Type:
SkDEBUGFAIL("Should never get here with an empty element.");
break;
case Element::kRect_Type:
return dc->drawContextPriv().drawAndStencilRect(clip, ss,
element->getOp(),
element->isInverseFilled(),
element->isAA(),
viewMatrix, element->getRect());
break;
default: {
SkPath path;
element->asPath(&path);
if (path.isInverseFillType()) {
path.toggleInverseFillType();
}
return dc->drawContextPriv().drawAndStencilPath(clip, ss,
element->getOp(),
element->isInverseFilled(),
element->isAA(), viewMatrix, path);
break;
}
}
return false;
}
static void draw_element(GrDrawContext* dc,
const GrClip& clip, // TODO: can this just always be WideOpen?
const GrPaint &paint,
const SkMatrix& viewMatrix,
const SkClipStack::Element* element) {
// TODO: Draw rrects directly here.
switch (element->getType()) {
case Element::kEmpty_Type:
SkDEBUGFAIL("Should never get here with an empty element.");
break;
case Element::kRect_Type:
dc->drawRect(clip, paint, viewMatrix, element->getRect());
break;
default: {
SkPath path;
element->asPath(&path);
if (path.isInverseFillType()) {
path.toggleInverseFillType();
}
dc->drawPath(clip, paint, viewMatrix, path, GrStyle::SimpleFill());
break;
}
}
}
////////////////////////////////////////////////////////////////////////////////
// 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<GrTexture> GrClipMaskManager::CreateAlphaClipMask(GrContext* context,
int32_t elementsGenID,
GrReducedClip::InitialState initialState,
const GrReducedClip::ElementList& elements,
const SkVector& clipToMaskOffset,
const SkIRect& clipSpaceIBounds) {
GrResourceProvider* resourceProvider = context->resourceProvider();
GrUniqueKey key;
GetClipMaskKey(elementsGenID, clipSpaceIBounds, &key);
if (GrTexture* texture = resourceProvider->findAndRefTextureByUniqueKey(key)) {
return sk_sp<GrTexture>(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<GrDrawContext> dc(context->newDrawContext(SkBackingFit::kApprox,
clipSpaceIBounds.width(),
clipSpaceIBounds.height(),
config));
if (!dc) {
return nullptr;
}
// The texture may be larger than necessary, this rect represents the part of the texture
// we populate with a rasterization of the clip.
SkIRect maskSpaceIBounds = SkIRect::MakeWH(clipSpaceIBounds.width(), clipSpaceIBounds.height());
// The scratch texture that we are drawing into can be substantially larger than the mask. Only
// clear the part that we care about.
dc->clear(&maskSpaceIBounds,
GrReducedClip::kAllIn_InitialState == initialState ? 0xffffffff : 0x00000000,
true);
// Set the matrix so that rendered clip elements are transformed to mask space from clip
// space.
const SkMatrix translate = SkMatrix::MakeTrans(clipToMaskOffset.fX, clipToMaskOffset.fY);
// It is important that we use maskSpaceIBounds as the stencil rect in the below loop.
// The second pass that zeros the stencil buffer renders the rect maskSpaceIBounds so the first
// pass must not set values outside of this bounds or stencil values outside the rect won't be
// cleared.
// walk through each clip element and perform its set op
for (GrReducedClip::ElementList::Iter iter = elements.headIter(); iter.get(); iter.next()) {
const Element* element = iter.get();
SkRegion::Op op = element->getOp();
bool invert = element->isInverseFilled();
if (invert || SkRegion::kIntersect_Op == op || SkRegion::kReverseDifference_Op == op) {
GrFixedClip clip(maskSpaceIBounds);
// draw directly into the result with the stencil set to make the pixels affected
// by the clip shape be non-zero.
static constexpr GrUserStencilSettings kStencilInElement(
GrUserStencilSettings::StaticInit<
0xffff,
GrUserStencilTest::kAlways,
0xffff,
GrUserStencilOp::kReplace,
GrUserStencilOp::kReplace,
0xffff>()
);
if (!stencil_element(dc.get(), clip, &kStencilInElement,
translate, element)) {
return nullptr;
}
// Draw to the exterior pixels (those with a zero stencil value).
static constexpr GrUserStencilSettings kDrawOutsideElement(
GrUserStencilSettings::StaticInit<
0x0000,
GrUserStencilTest::kEqual,
0xffff,
GrUserStencilOp::kZero,
GrUserStencilOp::kZero,
0xffff>()
);
if (!dc->drawContextPriv().drawAndStencilRect(clip, &kDrawOutsideElement,
op, !invert, false,
translate,
SkRect::Make(clipSpaceIBounds))) {
return nullptr;
}
} else {
// all the remaining ops can just be directly draw into the accumulation buffer
GrPaint paint;
paint.setAntiAlias(element->isAA());
paint.setCoverageSetOpXPFactory(op, false);
draw_element(dc.get(), GrNoClip(), paint, translate, element);
}
}
sk_sp<GrTexture> texture(dc->asTexture());
SkASSERT(texture);
texture->resourcePriv().setUniqueKey(key);
return texture;
}
////////////////////////////////////////////////////////////////////////////////
// Create a 1-bit clip mask in the stencil buffer. 'devClipBounds' are in device
// (as opposed to canvas) coordinates
bool GrClipMaskManager::CreateStencilClipMask(GrContext* context,
GrDrawContext* drawContext,
int32_t elementsGenID,
GrReducedClip::InitialState initialState,
const GrReducedClip::ElementList& elements,
const SkIRect& clipSpaceIBounds,
const SkIPoint& clipSpaceToStencilOffset) {
SkASSERT(drawContext);
GrStencilAttachment* stencilAttachment = context->resourceProvider()->attachStencilAttachment(
drawContext->accessRenderTarget());
if (nullptr == stencilAttachment) {
return false;
}
// TODO: these need to be swapped over to using a StencilAttachmentProxy
if (stencilAttachment->mustRenderClip(elementsGenID, clipSpaceIBounds, clipSpaceToStencilOffset)) {
stencilAttachment->setLastClip(elementsGenID, clipSpaceIBounds, clipSpaceToStencilOffset);
// Set the matrix so that rendered clip elements are transformed from clip to stencil space.
SkVector translate = {
SkIntToScalar(clipSpaceToStencilOffset.fX),
SkIntToScalar(clipSpaceToStencilOffset.fY)
};
SkMatrix viewMatrix;
viewMatrix.setTranslate(translate);
// We set the current clip to the bounds so that our recursive draws are scissored to them.
SkIRect stencilSpaceIBounds(clipSpaceIBounds);
stencilSpaceIBounds.offset(clipSpaceToStencilOffset);
GrFixedClip clip(stencilSpaceIBounds);
drawContext->drawContextPriv().clearStencilClip(
stencilSpaceIBounds,
GrReducedClip::kAllIn_InitialState == initialState);
// walk through each clip element and perform its set op
// with the existing clip.
for (GrReducedClip::ElementList::Iter iter(elements.headIter()); iter.get(); iter.next()) {
const Element* element = iter.get();
bool useHWAA = element->isAA() && drawContext->isStencilBufferMultisampled();
bool fillInverted = false;
// enabled at bottom of loop
clip.enableStencilClip(false);
// This will be used to determine whether the clip shape can be rendered into the
// stencil with arbitrary stencil settings.
GrPathRenderer::StencilSupport stencilSupport;
SkRegion::Op op = element->getOp();
GrPathRenderer* pr = nullptr;
SkPath clipPath;
if (Element::kRect_Type == element->getType()) {
stencilSupport = GrPathRenderer::kNoRestriction_StencilSupport;
fillInverted = false;
} else {
element->asPath(&clipPath);
fillInverted = clipPath.isInverseFillType();
if (fillInverted) {
clipPath.toggleInverseFillType();
}
GrPathRenderer::CanDrawPathArgs canDrawArgs;
canDrawArgs.fShaderCaps = context->caps()->shaderCaps();
canDrawArgs.fViewMatrix = &viewMatrix;
canDrawArgs.fPath = &clipPath;
canDrawArgs.fStyle = &GrStyle::SimpleFill();
canDrawArgs.fAntiAlias = false;
canDrawArgs.fHasUserStencilSettings = false;
canDrawArgs.fIsStencilBufferMSAA = drawContext->isStencilBufferMultisampled();
pr = context->drawingManager()->getPathRenderer(canDrawArgs, false,
GrPathRendererChain::kStencilOnly_DrawType,
&stencilSupport);
if (!pr) {
return false;
}
}
bool canRenderDirectToStencil =
GrPathRenderer::kNoRestriction_StencilSupport == stencilSupport;
bool drawDirectToClip; // Given the renderer, the element,
// fill rule, and set operation should
// we render the element directly to
// stencil bit used for clipping.
GrUserStencilSettings const* const* stencilPasses =
GrStencilSettings::GetClipPasses(op, canRenderDirectToStencil, fillInverted,
&drawDirectToClip);
// draw the element to the client stencil bits if necessary
if (!drawDirectToClip) {
static constexpr GrUserStencilSettings kDrawToStencil(
GrUserStencilSettings::StaticInit<
0x0000,
GrUserStencilTest::kAlways,
0xffff,
GrUserStencilOp::kIncMaybeClamp,
GrUserStencilOp::kIncMaybeClamp,
0xffff>()
);
if (Element::kRect_Type == element->getType()) {
drawContext->drawContextPriv().stencilRect(clip, &kDrawToStencil, useHWAA,
viewMatrix, element->getRect());
} else {
if (!clipPath.isEmpty()) {
if (canRenderDirectToStencil) {
GrPaint paint;
paint.setXPFactory(GrDisableColorXPFactory::Make());
paint.setAntiAlias(element->isAA());
GrPathRenderer::DrawPathArgs args;
args.fResourceProvider = context->resourceProvider();
args.fPaint = &paint;
args.fUserStencilSettings = &kDrawToStencil;
args.fDrawContext = drawContext;
args.fClip = &clip;
args.fColor = GrColor_WHITE;
args.fViewMatrix = &viewMatrix;
args.fPath = &clipPath;
args.fStyle = &GrStyle::SimpleFill();
args.fAntiAlias = false;
args.fGammaCorrect = false;
pr->drawPath(args);
} else {
GrPathRenderer::StencilPathArgs args;
args.fResourceProvider = context->resourceProvider();
args.fDrawContext = drawContext;
args.fClip = &clip;
args.fViewMatrix = &viewMatrix;
args.fPath = &clipPath;
args.fIsAA = element->isAA();
pr->stencilPath(args);
}
}
}
}
// now we modify the clip bit by rendering either the clip
// element directly or a bounding rect of the entire clip.
clip.enableStencilClip(true);
for (GrUserStencilSettings const* const* pass = stencilPasses; *pass; ++pass) {
if (drawDirectToClip) {
if (Element::kRect_Type == element->getType()) {
drawContext->drawContextPriv().stencilRect(clip, *pass, useHWAA, viewMatrix,
element->getRect());
} else {
GrPaint paint;
paint.setXPFactory(GrDisableColorXPFactory::Make());
paint.setAntiAlias(element->isAA());
GrPathRenderer::DrawPathArgs args;
args.fResourceProvider = context->resourceProvider();
args.fPaint = &paint;
args.fUserStencilSettings = *pass;
args.fDrawContext = drawContext;
args.fClip = &clip;
args.fColor = GrColor_WHITE;
args.fViewMatrix = &viewMatrix;
args.fPath = &clipPath;
args.fStyle = &GrStyle::SimpleFill();
args.fAntiAlias = false;
args.fGammaCorrect = false;
pr->drawPath(args);
}
} else {
// The view matrix is setup to do clip space -> stencil space translation, so
// draw rect in clip space.
drawContext->drawContextPriv().stencilRect(clip, *pass, false, viewMatrix,
SkRect::Make(clipSpaceIBounds));
}
}
}
}
return true;
}
////////////////////////////////////////////////////////////////////////////////
sk_sp<GrTexture> GrClipMaskManager::CreateSoftwareClipMask(
GrTextureProvider* texProvider,
int32_t elementsGenID,
GrReducedClip::InitialState initialState,
const GrReducedClip::ElementList& elements,
const SkVector& clipToMaskOffset,
const SkIRect& clipSpaceIBounds) {
GrUniqueKey key;
GetClipMaskKey(elementsGenID, clipSpaceIBounds, &key);
if (GrTexture* texture = texProvider->findAndRefTextureByUniqueKey(key)) {
return sk_sp<GrTexture>(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(clipSpaceIBounds.width(), clipSpaceIBounds.height());
GrSWMaskHelper helper(texProvider);
// Set the matrix so that rendered clip elements are transformed to mask space from clip
// space.
SkMatrix translate;
translate.setTranslate(clipToMaskOffset);
helper.init(maskSpaceIBounds, &translate);
helper.clear(GrReducedClip::kAllIn_InitialState == initialState ? 0xFF : 0x00);
for (GrReducedClip::ElementList::Iter iter(elements.headIter()) ; 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(clipSpaceIBounds);
// invert the entire scene
helper.drawRect(temp, SkRegion::kXOR_Op, false, 0xFF);
}
SkPath clipPath;
element->asPath(&clipPath);
clipPath.toggleInverseFillType();
helper.drawPath(clipPath, GrStyle::SimpleFill(), 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);
helper.drawPath(path, GrStyle::SimpleFill(), op, element->isAA(), 0xFF);
}
}
// Allocate clip mask texture
GrSurfaceDesc desc;
desc.fWidth = clipSpaceIBounds.width();
desc.fHeight = clipSpaceIBounds.height();
desc.fConfig = kAlpha_8_GrPixelConfig;
sk_sp<GrTexture> result(texProvider->createApproxTexture(desc));
if (!result) {
return nullptr;
}
result->resourcePriv().setUniqueKey(key);
helper.toTexture(result.get());
return result;
}
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