/*
* 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 "GrAAConvexPathRenderer.h"
#include "GrAAHairLinePathRenderer.h"
#include "GrAARectRenderer.h"
#include "GrDrawTargetCaps.h"
#include "GrPaint.h"
#include "GrPathRenderer.h"
#include "GrRenderTarget.h"
#include "GrRenderTargetPriv.h"
#include "GrStencilAttachment.h"
#include "GrSWMaskHelper.h"
#include "SkRasterClip.h"
#include "SkTLazy.h"
#include "effects/GrConvexPolyEffect.h"
#include "effects/GrPorterDuffXferProcessor.h"
#include "effects/GrRRectEffect.h"
#include "effects/GrTextureDomain.h"
typedef SkClipStack::Element Element;
////////////////////////////////////////////////////////////////////////////////
namespace {
// set up the draw state to enable the aa clipping mask. Besides setting up the
// stage matrix this also alters the vertex layout
void setup_drawstate_aaclip(GrPipelineBuilder* pipelineBuilder,
GrTexture* result,
GrPipelineBuilder::AutoRestoreFragmentProcessors* arfp,
const SkIRect &devBound) {
SkASSERT(pipelineBuilder && arfp);
arfp->set(pipelineBuilder);
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());
// This could be a long-lived effect that is cached with the alpha-mask.
pipelineBuilder->addCoverageProcessor(
GrTextureDomainEffect::Create(result,
mat,
GrTextureDomain::MakeTexelDomain(result, domainTexels),
GrTextureDomain::kDecal_Mode,
GrTextureParams::kNone_FilterMode,
kDevice_GrCoordSet))->unref();
}
bool path_needs_SW_renderer(GrContext* context,
const GrDrawTarget* gpu,
const GrPipelineBuilder* pipelineBuilder,
const SkMatrix& viewMatrix,
const SkPath& origPath,
const GrStrokeInfo& stroke,
bool doAA) {
// the gpu alpha mask will draw the inverse paths as non-inverse to a temp buffer
SkTCopyOnFirstWrite<SkPath> path(origPath);
if (path->isInverseFillType()) {
path.writable()->toggleInverseFillType();
}
// last (false) parameter disallows use of the SW path renderer
GrPathRendererChain::DrawType type = doAA ?
GrPathRendererChain::kColorAntiAlias_DrawType :
GrPathRendererChain::kColor_DrawType;
return NULL == context->getPathRenderer(gpu, pipelineBuilder, viewMatrix, *path, stroke,
false, type);
}
}
/*
* 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(const GrPipelineBuilder* pipelineBuilder,
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.
GrStrokeInfo stroke(SkStrokeRec::kFill_InitStyle);
// Set the matrix so that rendered clip elements are transformed to mask space from clip
// space.
SkMatrix translate;
translate.setTranslate(clipToMaskOffset);
for (GrReducedClip::ElementList::Iter iter(elements.headIter()); iter.get(); iter.next()) {
const Element* element = iter.get();
// rects can always be drawn directly w/o using the software path
// Skip rrects once we're drawing them directly.
if (Element::kRect_Type != element->getType()) {
SkPath path;
element->asPath(&path);
if (path_needs_SW_renderer(this->getContext(), fClipTarget, pipelineBuilder, translate,
path, stroke, element->isAA())) {
return true;
}
}
}
return false;
}
bool GrClipMaskManager::installClipEffects(GrPipelineBuilder* pipelineBuilder,
GrPipelineBuilder::AutoRestoreFragmentProcessors* arfp,
const GrReducedClip::ElementList& elements,
const SkVector& clipToRTOffset,
const SkRect* drawBounds) {
SkRect boundsInClipSpace;
if (drawBounds) {
boundsInClipSpace = *drawBounds;
boundsInClipSpace.offset(-clipToRTOffset.fX, -clipToRTOffset.fY);
}
arfp->set(pipelineBuilder);
GrRenderTarget* rt = pipelineBuilder->getRenderTarget();
GrReducedClip::ElementList::Iter iter(elements);
bool failed = false;
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:
failed = true;
break;
}
if (failed) {
break;
}
if (!skip) {
GrPrimitiveEdgeType edgeType;
if (iter.get()->isAA()) {
if (rt->isMultisampled()) {
// Coverage based AA clips don't place nicely with MSAA.
failed = true;
break;
}
edgeType =
invert ? kInverseFillAA_GrProcessorEdgeType : kFillAA_GrProcessorEdgeType;
} else {
edgeType =
invert ? kInverseFillBW_GrProcessorEdgeType : kFillBW_GrProcessorEdgeType;
}
SkAutoTUnref<GrFragmentProcessor> fp;
switch (iter.get()->getType()) {
case SkClipStack::Element::kPath_Type:
fp.reset(GrConvexPolyEffect::Create(edgeType, iter.get()->getPath(),
&clipToRTOffset));
break;
case SkClipStack::Element::kRRect_Type: {
SkRRect rrect = iter.get()->getRRect();
rrect.offset(clipToRTOffset.fX, clipToRTOffset.fY);
fp.reset(GrRRectEffect::Create(edgeType, rrect));
break;
}
case SkClipStack::Element::kRect_Type: {
SkRect rect = iter.get()->getRect();
rect.offset(clipToRTOffset.fX, clipToRTOffset.fY);
fp.reset(GrConvexPolyEffect::Create(edgeType, rect));
break;
}
default:
break;
}
if (fp) {
pipelineBuilder->addCoverageProcessor(fp);
} else {
failed = true;
break;
}
}
iter.next();
}
if (failed) {
arfp->set(NULL);
}
return !failed;
}
////////////////////////////////////////////////////////////////////////////////
// sort out what kind of clip mask needs to be created: alpha, stencil,
// scissor, or entirely software
bool GrClipMaskManager::setupClipping(GrPipelineBuilder* pipelineBuilder,
GrPipelineBuilder::AutoRestoreFragmentProcessors* arfp,
GrPipelineBuilder::AutoRestoreStencil* ars,
GrScissorState* scissorState,
const SkRect* devBounds) {
fCurrClipMaskType = kNone_ClipMaskType;
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() <= 4) {
SkVector clipToRTOffset = { SkIntToScalar(-clip.origin().fX),
SkIntToScalar(-clip.origin().fY) };
if (elements.isEmpty() ||
(requiresAA && this->installClipEffects(pipelineBuilder, arfp, elements, clipToRTOffset,
devBounds))) {
SkIRect scissorSpaceIBounds(clipSpaceIBounds);
scissorSpaceIBounds.offset(-clip.origin());
if (NULL == devBounds ||
!SkRect::Make(scissorSpaceIBounds).contains(*devBounds)) {
scissorState->set(scissorSpaceIBounds);
}
this->setPipelineBuilderStencil(pipelineBuilder, ars);
return true;
}
}
// If MSAA is enabled we can do everything in the stencil buffer.
if (0 == rt->numSamples() && requiresAA) {
GrTexture* result = NULL;
// The top-left of the mask corresponds to the top-left corner of the bounds.
SkVector clipToMaskOffset = {
SkIntToScalar(-clipSpaceIBounds.fLeft),
SkIntToScalar(-clipSpaceIBounds.fTop)
};
if (this->useSWOnlyPath(pipelineBuilder, clipToMaskOffset, elements)) {
// The clip geometry is complex enough that it will be more efficient to create it
// entirely in software
result = this->createSoftwareClipMask(genID,
initialState,
elements,
clipToMaskOffset,
clipSpaceIBounds);
} else {
result = this->createAlphaClipMask(genID,
initialState,
elements,
clipToMaskOffset,
clipSpaceIBounds);
}
if (result) {
arfp->set(pipelineBuilder);
// 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());
setup_drawstate_aaclip(pipelineBuilder, result, arfp, rtSpaceMaskBounds);
this->setPipelineBuilderStencil(pipelineBuilder, ars);
return true;
}
// if alpha clip mask creation fails fall through to the non-AA code paths
}
// Either a hard (stencil buffer) clip was explicitly requested or an anti-aliased clip couldn't
// be created. In either case, free up the texture in the anti-aliased mask cache.
// TODO: this may require more investigation. Ganesh performs a lot of utility draws (e.g.,
// clears, InOrderDrawBuffer playbacks) that hit the stencil buffer path. These may be
// "incorrectly" clearing the AA cache.
fAACache.reset();
// use the stencil clip if we can't represent the clip as a rectangle.
SkIPoint clipSpaceToStencilSpaceOffset = -clip.origin();
this->createStencilClipMask(rt,
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);
scissorState->set(scissorSpaceIBounds);
this->setPipelineBuilderStencil(pipelineBuilder, ars);
return true;
}
namespace {
////////////////////////////////////////////////////////////////////////////////
// Set a coverage drawing XPF on the pipelineBuilder for the given op and invertCoverage mode
void set_coverage_drawing_xpf(SkRegion::Op op, bool invertCoverage,
GrPipelineBuilder* pipelineBuilder) {
SkASSERT(op <= SkRegion::kLastOp);
pipelineBuilder->setCoverageSetOpXPFactory(op, invertCoverage);
}
}
////////////////////////////////////////////////////////////////////////////////
bool GrClipMaskManager::drawElement(GrPipelineBuilder* pipelineBuilder,
const SkMatrix& viewMatrix,
GrTexture* target,
const SkClipStack::Element* element,
GrPathRenderer* pr) {
pipelineBuilder->setRenderTarget(target->asRenderTarget());
// The color we use to draw does not matter since we will always be using a GrCoverageSetOpXP
// which ignores color.
GrColor color = GrColor_WHITE;
// 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:
// TODO: Do rects directly to the accumulator using a aa-rect GrProcessor that covers
// the entire mask bounds and writes 0 outside the rect.
if (element->isAA()) {
SkRect devRect = element->getRect();
viewMatrix.mapRect(&devRect);
this->getContext()->getAARectRenderer()->fillAARect(fClipTarget,
pipelineBuilder,
color,
viewMatrix,
element->getRect(),
devRect);
} else {
fClipTarget->drawSimpleRect(pipelineBuilder, color, viewMatrix, element->getRect());
}
return true;
default: {
SkPath path;
element->asPath(&path);
path.setIsVolatile(true);
if (path.isInverseFillType()) {
path.toggleInverseFillType();
}
GrStrokeInfo stroke(SkStrokeRec::kFill_InitStyle);
if (NULL == pr) {
GrPathRendererChain::DrawType type;
type = element->isAA() ? GrPathRendererChain::kColorAntiAlias_DrawType :
GrPathRendererChain::kColor_DrawType;
pr = this->getContext()->getPathRenderer(fClipTarget, pipelineBuilder, viewMatrix,
path, stroke, false, type);
}
if (NULL == pr) {
return false;
}
pr->drawPath(fClipTarget, pipelineBuilder, color, viewMatrix, path, stroke,
element->isAA());
break;
}
}
return true;
}
bool GrClipMaskManager::canStencilAndDrawElement(GrPipelineBuilder* pipelineBuilder,
GrTexture* target,
GrPathRenderer** pr,
const SkClipStack::Element* element) {
pipelineBuilder->setRenderTarget(target->asRenderTarget());
if (Element::kRect_Type == element->getType()) {
return true;
} else {
// We shouldn't get here with an empty clip element.
SkASSERT(Element::kEmpty_Type != element->getType());
SkPath path;
element->asPath(&path);
if (path.isInverseFillType()) {
path.toggleInverseFillType();
}
GrStrokeInfo stroke(SkStrokeRec::kFill_InitStyle);
GrPathRendererChain::DrawType type = element->isAA() ?
GrPathRendererChain::kStencilAndColorAntiAlias_DrawType :
GrPathRendererChain::kStencilAndColor_DrawType;
*pr = this->getContext()->getPathRenderer(fClipTarget, pipelineBuilder, SkMatrix::I(), path,
stroke, false, type);
return SkToBool(*pr);
}
}
void GrClipMaskManager::mergeMask(GrPipelineBuilder* pipelineBuilder,
GrTexture* dstMask,
GrTexture* srcMask,
SkRegion::Op op,
const SkIRect& dstBound,
const SkIRect& srcBound) {
pipelineBuilder->setRenderTarget(dstMask->asRenderTarget());
// We want to invert the coverage here
set_coverage_drawing_xpf(op, false, pipelineBuilder);
SkMatrix sampleM;
sampleM.setIDiv(srcMask->width(), srcMask->height());
pipelineBuilder->addCoverageProcessor(
GrTextureDomainEffect::Create(srcMask,
sampleM,
GrTextureDomain::MakeTexelDomain(srcMask, srcBound),
GrTextureDomain::kDecal_Mode,
GrTextureParams::kNone_FilterMode))->unref();
// The color passed in here does not matter since the coverageSetOpXP won't read it.
fClipTarget->drawSimpleRect(pipelineBuilder,
GrColor_WHITE,
SkMatrix::I(),
SkRect::Make(dstBound));
}
GrTexture* GrClipMaskManager::createTempMask(int width, int height) {
GrSurfaceDesc desc;
desc.fFlags = kRenderTarget_GrSurfaceFlag;
desc.fWidth = width;
desc.fHeight = height;
if (this->getContext()->isConfigRenderable(kAlpha_8_GrPixelConfig, false)) {
desc.fConfig = kAlpha_8_GrPixelConfig;
} else {
desc.fConfig = kRGBA_8888_GrPixelConfig;
}
return this->getContext()->textureProvider()->refScratchTexture(
desc, GrTextureProvider::kApprox_ScratchTexMatch);
}
////////////////////////////////////////////////////////////////////////////////
// Return the texture currently in the cache if it exists. Otherwise, return NULL
GrTexture* GrClipMaskManager::getCachedMaskTexture(int32_t elementsGenID,
const SkIRect& clipSpaceIBounds) {
bool cached = fAACache.canReuse(elementsGenID, clipSpaceIBounds);
if (!cached) {
return NULL;
}
return fAACache.getLastMask();
}
////////////////////////////////////////////////////////////////////////////////
// Allocate a texture in the texture cache. This function returns the texture
// allocated (or NULL on error).
GrTexture* GrClipMaskManager::allocMaskTexture(int32_t elementsGenID,
const SkIRect& clipSpaceIBounds,
bool willUpload) {
// Since we are setting up the cache we should free up the
// currently cached mask so it can be reused.
fAACache.reset();
GrSurfaceDesc desc;
desc.fFlags = willUpload ? kNone_GrSurfaceFlags : kRenderTarget_GrSurfaceFlag;
desc.fWidth = clipSpaceIBounds.width();
desc.fHeight = clipSpaceIBounds.height();
desc.fConfig = kRGBA_8888_GrPixelConfig;
if (willUpload || this->getContext()->isConfigRenderable(kAlpha_8_GrPixelConfig, false)) {
// We would always like A8 but it isn't supported on all platforms
desc.fConfig = kAlpha_8_GrPixelConfig;
}
fAACache.acquireMask(elementsGenID, desc, clipSpaceIBounds);
return fAACache.getLastMask();
}
////////////////////////////////////////////////////////////////////////////////
// Create a 8-bit clip mask in alpha
GrTexture* GrClipMaskManager::createAlphaClipMask(int32_t elementsGenID,
GrReducedClip::InitialState initialState,
const GrReducedClip::ElementList& elements,
const SkVector& clipToMaskOffset,
const SkIRect& clipSpaceIBounds) {
SkASSERT(kNone_ClipMaskType == fCurrClipMaskType);
// First, check for cached texture
GrTexture* result = this->getCachedMaskTexture(elementsGenID, clipSpaceIBounds);
if (result) {
fCurrClipMaskType = kAlpha_ClipMaskType;
return result;
}
// There's no texture in the cache. Let's try to allocate it then.
result = this->allocMaskTexture(elementsGenID, clipSpaceIBounds, false);
if (NULL == result) {
fAACache.reset();
return NULL;
}
// Set the matrix so that rendered clip elements are transformed to mask space from clip
// space.
SkMatrix translate;
translate.setTranslate(clipToMaskOffset);
// 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.
fClipTarget->clear(&maskSpaceIBounds,
GrReducedClip::kAllIn_InitialState == initialState ? 0xffffffff : 0x00000000,
true,
result->asRenderTarget());
// When we use the stencil in the below loop it is important to have this clip installed.
// 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.
GrClip clip(maskSpaceIBounds);
SkAutoTUnref<GrTexture> temp;
// 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) {
GrPipelineBuilder pipelineBuilder;
pipelineBuilder.setClip(clip);
GrPathRenderer* pr = NULL;
bool useTemp = !this->canStencilAndDrawElement(&pipelineBuilder, result, &pr, element);
GrTexture* dst;
// This is the bounds of the clip element in the space of the alpha-mask. The temporary
// mask buffer can be substantially larger than the actually clip stack element. We
// touch the minimum number of pixels necessary and use decal mode to combine it with
// the accumulator.
SkIRect maskSpaceElementIBounds;
if (useTemp) {
if (invert) {
maskSpaceElementIBounds = maskSpaceIBounds;
} else {
SkRect elementBounds = element->getBounds();
elementBounds.offset(clipToMaskOffset);
elementBounds.roundOut(&maskSpaceElementIBounds);
}
if (!temp) {
temp.reset(this->createTempMask(maskSpaceIBounds.fRight,
maskSpaceIBounds.fBottom));
if (!temp) {
fAACache.reset();
return NULL;
}
}
dst = temp;
// clear the temp target and set blend to replace
fClipTarget->clear(&maskSpaceElementIBounds,
invert ? 0xffffffff : 0x00000000,
true,
dst->asRenderTarget());
set_coverage_drawing_xpf(SkRegion::kReplace_Op, invert, &pipelineBuilder);
} else {
// draw directly into the result with the stencil set to make the pixels affected
// by the clip shape be non-zero.
dst = result;
GR_STATIC_CONST_SAME_STENCIL(kStencilInElement,
kReplace_StencilOp,
kReplace_StencilOp,
kAlways_StencilFunc,
0xffff,
0xffff,
0xffff);
pipelineBuilder.setStencil(kStencilInElement);
set_coverage_drawing_xpf(op, invert, &pipelineBuilder);
}
if (!this->drawElement(&pipelineBuilder, translate, dst, element, pr)) {
fAACache.reset();
return NULL;
}
if (useTemp) {
GrPipelineBuilder backgroundPipelineBuilder;
backgroundPipelineBuilder.setRenderTarget(result->asRenderTarget());
// Now draw into the accumulator using the real operation and the temp buffer as a
// texture
this->mergeMask(&backgroundPipelineBuilder,
result,
temp,
op,
maskSpaceIBounds,
maskSpaceElementIBounds);
} else {
GrPipelineBuilder backgroundPipelineBuilder;
backgroundPipelineBuilder.setRenderTarget(result->asRenderTarget());
set_coverage_drawing_xpf(op, !invert, &backgroundPipelineBuilder);
// Draw to the exterior pixels (those with a zero stencil value).
GR_STATIC_CONST_SAME_STENCIL(kDrawOutsideElement,
kZero_StencilOp,
kZero_StencilOp,
kEqual_StencilFunc,
0xffff,
0x0000,
0xffff);
backgroundPipelineBuilder.setStencil(kDrawOutsideElement);
// The color passed in here does not matter since the coverageSetOpXP won't read it.
fClipTarget->drawSimpleRect(&backgroundPipelineBuilder, GrColor_WHITE, translate,
clipSpaceIBounds);
}
} else {
GrPipelineBuilder pipelineBuilder;
// all the remaining ops can just be directly draw into the accumulation buffer
set_coverage_drawing_xpf(op, false, &pipelineBuilder);
// The color passed in here does not matter since the coverageSetOpXP won't read it.
this->drawElement(&pipelineBuilder, translate, result, element);
}
}
fCurrClipMaskType = kAlpha_ClipMaskType;
return result;
}
////////////////////////////////////////////////////////////////////////////////
// Create a 1-bit clip mask in the stencil buffer. 'devClipBounds' are in device
// (as opposed to canvas) coordinates
bool GrClipMaskManager::createStencilClipMask(GrRenderTarget* rt,
int32_t elementsGenID,
GrReducedClip::InitialState initialState,
const GrReducedClip::ElementList& elements,
const SkIRect& clipSpaceIBounds,
const SkIPoint& clipSpaceToStencilOffset) {
SkASSERT(kNone_ClipMaskType == fCurrClipMaskType);
SkASSERT(rt);
GrStencilAttachment* stencilAttachment = rt->renderTargetPriv().attachStencilAttachment();
if (NULL == stencilAttachment) {
return false;
}
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);
GrClip clip(stencilSpaceIBounds);
int clipBit = stencilAttachment->bits();
SkASSERT((clipBit <= 16) && "Ganesh only handles 16b or smaller stencil buffers");
clipBit = (1 << (clipBit-1));
fClipTarget->clearStencilClip(stencilSpaceIBounds,
GrReducedClip::kAllIn_InitialState == initialState,
rt);
// 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();
GrPipelineBuilder pipelineBuilder;
pipelineBuilder.setClip(clip);
pipelineBuilder.setRenderTarget(rt);
pipelineBuilder.setDisableColorXPFactory();
// if the target is MSAA then we want MSAA enabled when the clip is soft
if (rt->isMultisampled()) {
pipelineBuilder.setState(GrPipelineBuilder::kHWAntialias_Flag, element->isAA());
}
bool fillInverted = false;
// enabled at bottom of loop
fClipMode = kIgnoreClip_StencilClipMode;
// This will be used to determine whether the clip shape can be rendered into the
// stencil with arbitrary stencil settings.
GrPathRenderer::StencilSupport stencilSupport;
GrStrokeInfo stroke(SkStrokeRec::kFill_InitStyle);
SkRegion::Op op = element->getOp();
GrPathRenderer* pr = NULL;
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();
}
pr = this->getContext()->getPathRenderer(fClipTarget,
&pipelineBuilder,
viewMatrix,
clipPath,
stroke,
false,
GrPathRendererChain::kStencilOnly_DrawType,
&stencilSupport);
if (NULL == pr) {
return false;
}
}
int passes;
GrStencilSettings stencilSettings[GrStencilSettings::kMaxStencilClipPasses];
bool canRenderDirectToStencil =
GrPathRenderer::kNoRestriction_StencilSupport == stencilSupport;
bool canDrawDirectToClip; // Given the renderer, the element,
// fill rule, and set operation can
// we render the element directly to
// stencil bit used for clipping.
canDrawDirectToClip = GrStencilSettings::GetClipPasses(op,
canRenderDirectToStencil,
clipBit,
fillInverted,
&passes,
stencilSettings);
// draw the element to the client stencil bits if necessary
if (!canDrawDirectToClip) {
GR_STATIC_CONST_SAME_STENCIL(gDrawToStencil,
kIncClamp_StencilOp,
kIncClamp_StencilOp,
kAlways_StencilFunc,
0xffff,
0x0000,
0xffff);
if (Element::kRect_Type == element->getType()) {
*pipelineBuilder.stencil() = gDrawToStencil;
// We need this AGP until everything is in GrBatch
fClipTarget->drawSimpleRect(&pipelineBuilder,
GrColor_WHITE,
viewMatrix,
element->getRect());
} else {
if (!clipPath.isEmpty()) {
if (canRenderDirectToStencil) {
*pipelineBuilder.stencil() = gDrawToStencil;
pr->drawPath(fClipTarget, &pipelineBuilder, GrColor_WHITE,
viewMatrix, clipPath, stroke, false);
} else {
pr->stencilPath(fClipTarget, &pipelineBuilder, viewMatrix,
clipPath, stroke);
}
}
}
}
// now we modify the clip bit by rendering either the clip
// element directly or a bounding rect of the entire clip.
fClipMode = kModifyClip_StencilClipMode;
for (int p = 0; p < passes; ++p) {
GrPipelineBuilder pipelineBuilderCopy(pipelineBuilder);
*pipelineBuilderCopy.stencil() = stencilSettings[p];
if (canDrawDirectToClip) {
if (Element::kRect_Type == element->getType()) {
// We need this AGP until everything is in GrBatch
fClipTarget->drawSimpleRect(&pipelineBuilderCopy,
GrColor_WHITE,
viewMatrix,
element->getRect());
} else {
pr->drawPath(fClipTarget, &pipelineBuilderCopy, GrColor_WHITE,
viewMatrix, clipPath, stroke, false);
}
} else {
// The view matrix is setup to do clip space -> stencil space translation, so
// draw rect in clip space.
fClipTarget->drawSimpleRect(&pipelineBuilderCopy,
GrColor_WHITE,
viewMatrix,
SkRect::Make(clipSpaceIBounds));
}
}
}
}
// set this last because recursive draws may overwrite it back to kNone.
SkASSERT(kNone_ClipMaskType == fCurrClipMaskType);
fCurrClipMaskType = kStencil_ClipMaskType;
fClipMode = kRespectClip_StencilClipMode;
return true;
}
// mapping of clip-respecting stencil funcs to normal stencil funcs
// mapping depends on whether stencil-clipping is in effect.
static const GrStencilFunc
gSpecialToBasicStencilFunc[2][kClipStencilFuncCount] = {
{// Stencil-Clipping is DISABLED, we are effectively always inside the clip
// In the Clip Funcs
kAlways_StencilFunc, // kAlwaysIfInClip_StencilFunc
kEqual_StencilFunc, // kEqualIfInClip_StencilFunc
kLess_StencilFunc, // kLessIfInClip_StencilFunc
kLEqual_StencilFunc, // kLEqualIfInClip_StencilFunc
// Special in the clip func that forces user's ref to be 0.
kNotEqual_StencilFunc, // kNonZeroIfInClip_StencilFunc
// make ref 0 and do normal nequal.
},
{// Stencil-Clipping is ENABLED
// In the Clip Funcs
kEqual_StencilFunc, // kAlwaysIfInClip_StencilFunc
// eq stencil clip bit, mask
// out user bits.
kEqual_StencilFunc, // kEqualIfInClip_StencilFunc
// add stencil bit to mask and ref
kLess_StencilFunc, // kLessIfInClip_StencilFunc
kLEqual_StencilFunc, // kLEqualIfInClip_StencilFunc
// for both of these we can add
// the clip bit to the mask and
// ref and compare as normal
// Special in the clip func that forces user's ref to be 0.
kLess_StencilFunc, // kNonZeroIfInClip_StencilFunc
// make ref have only the clip bit set
// and make comparison be less
// 10..0 < 1..user_bits..
}
};
namespace {
// Sets the settings to clip against the stencil buffer clip while ignoring the
// client bits.
const GrStencilSettings& basic_apply_stencil_clip_settings() {
// stencil settings to use when clip is in stencil
GR_STATIC_CONST_SAME_STENCIL_STRUCT(gSettings,
kKeep_StencilOp,
kKeep_StencilOp,
kAlwaysIfInClip_StencilFunc,
0x0000,
0x0000,
0x0000);
return *GR_CONST_STENCIL_SETTINGS_PTR_FROM_STRUCT_PTR(&gSettings);
}
}
void GrClipMaskManager::setPipelineBuilderStencil(GrPipelineBuilder* pipelineBuilder,
GrPipelineBuilder::AutoRestoreStencil* ars) {
// We make two copies of the StencilSettings here (except in the early
// exit scenario. One copy from draw state to the stack var. Then another
// from the stack var to the gpu. We could make this class hold a ptr to
// GrGpu's fStencilSettings and eliminate the stack copy here.
// use stencil for clipping if clipping is enabled and the clip
// has been written into the stencil.
GrStencilSettings settings;
// The GrGpu client may not be using the stencil buffer but we may need to
// enable it in order to respect a stencil clip.
if (pipelineBuilder->getStencil().isDisabled()) {
if (GrClipMaskManager::kRespectClip_StencilClipMode == fClipMode) {
settings = basic_apply_stencil_clip_settings();
} else {
return;
}
} else {
settings = pipelineBuilder->getStencil();
}
int stencilBits = 0;
GrRenderTarget* rt = pipelineBuilder->getRenderTarget();
GrStencilAttachment* stencilAttachment = rt->renderTargetPriv().attachStencilAttachment();
if (stencilAttachment) {
stencilBits = stencilAttachment->bits();
}
SkASSERT(fClipTarget->caps()->stencilWrapOpsSupport() || !settings.usesWrapOp());
SkASSERT(fClipTarget->caps()->twoSidedStencilSupport() || !settings.isTwoSided());
this->adjustStencilParams(&settings, fClipMode, stencilBits);
ars->set(pipelineBuilder);
pipelineBuilder->setStencil(settings);
}
void GrClipMaskManager::adjustStencilParams(GrStencilSettings* settings,
StencilClipMode mode,
int stencilBitCnt) {
SkASSERT(stencilBitCnt > 0);
if (kModifyClip_StencilClipMode == mode) {
// We assume that this clip manager itself is drawing to the GrGpu and
// has already setup the correct values.
return;
}
unsigned int clipBit = (1 << (stencilBitCnt - 1));
unsigned int userBits = clipBit - 1;
GrStencilSettings::Face face = GrStencilSettings::kFront_Face;
bool twoSided = fClipTarget->caps()->twoSidedStencilSupport();
bool finished = false;
while (!finished) {
GrStencilFunc func = settings->func(face);
uint16_t writeMask = settings->writeMask(face);
uint16_t funcMask = settings->funcMask(face);
uint16_t funcRef = settings->funcRef(face);
SkASSERT((unsigned) func < kStencilFuncCount);
writeMask &= userBits;
if (func >= kBasicStencilFuncCount) {
int respectClip = kRespectClip_StencilClipMode == mode;
if (respectClip) {
// The GrGpu class should have checked this
SkASSERT(this->isClipInStencil());
switch (func) {
case kAlwaysIfInClip_StencilFunc:
funcMask = clipBit;
funcRef = clipBit;
break;
case kEqualIfInClip_StencilFunc:
case kLessIfInClip_StencilFunc:
case kLEqualIfInClip_StencilFunc:
funcMask = (funcMask & userBits) | clipBit;
funcRef = (funcRef & userBits) | clipBit;
break;
case kNonZeroIfInClip_StencilFunc:
funcMask = (funcMask & userBits) | clipBit;
funcRef = clipBit;
break;
default:
SkFAIL("Unknown stencil func");
}
} else {
funcMask &= userBits;
funcRef &= userBits;
}
const GrStencilFunc* table =
gSpecialToBasicStencilFunc[respectClip];
func = table[func - kBasicStencilFuncCount];
SkASSERT(func >= 0 && func < kBasicStencilFuncCount);
} else {
funcMask &= userBits;
funcRef &= userBits;
}
settings->setFunc(face, func);
settings->setWriteMask(face, writeMask);
settings->setFuncMask(face, funcMask);
settings->setFuncRef(face, funcRef);
if (GrStencilSettings::kFront_Face == face) {
face = GrStencilSettings::kBack_Face;
finished = !twoSided;
} else {
finished = true;
}
}
if (!twoSided) {
settings->copyFrontSettingsToBack();
}
}
////////////////////////////////////////////////////////////////////////////////
GrTexture* GrClipMaskManager::createSoftwareClipMask(int32_t elementsGenID,
GrReducedClip::InitialState initialState,
const GrReducedClip::ElementList& elements,
const SkVector& clipToMaskOffset,
const SkIRect& clipSpaceIBounds) {
SkASSERT(kNone_ClipMaskType == fCurrClipMaskType);
GrTexture* result = this->getCachedMaskTexture(elementsGenID, clipSpaceIBounds);
if (result) {
return result;
}
// 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(this->getContext());
// 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, false);
helper.clear(GrReducedClip::kAllIn_InitialState == initialState ? 0xFF : 0x00);
SkStrokeRec stroke(SkStrokeRec::kFill_InitStyle);
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.draw(temp, SkRegion::kXOR_Op, false, 0xFF);
}
SkPath clipPath;
element->asPath(&clipPath);
clipPath.toggleInverseFillType();
helper.draw(clipPath, stroke, 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.draw(element->getRect(), op, element->isAA(), 0xFF);
} else {
SkPath path;
element->asPath(&path);
helper.draw(path, stroke, op, element->isAA(), 0xFF);
}
}
// Allocate clip mask texture
result = this->allocMaskTexture(elementsGenID, clipSpaceIBounds, true);
if (NULL == result) {
fAACache.reset();
return NULL;
}
helper.toTexture(result);
fCurrClipMaskType = kAlpha_ClipMaskType;
return result;
}
////////////////////////////////////////////////////////////////////////////////
void GrClipMaskManager::purgeResources() {
fAACache.purgeResources();
}
void GrClipMaskManager::setClipTarget(GrClipTarget* clipTarget) {
fClipTarget = clipTarget;
fAACache.setContext(clipTarget->getContext());
}
void GrClipMaskManager::adjustPathStencilParams(const GrStencilAttachment* stencilAttachment,
GrStencilSettings* settings) {
if (stencilAttachment) {
int stencilBits = stencilAttachment->bits();
this->adjustStencilParams(settings, fClipMode, stencilBits);
}
}