blob: 003b4a5d439bb63782dd1370ea6bc7a0f94b4172 [file] [log] [blame]
/*
* 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<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,
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<GrFragmentProcessor>* resultFP) {
SkRect boundsInClipSpace;
boundsInClipSpace = drawBounds.makeOffset(-clipToRTOffset.fX, -clipToRTOffset.fY);
SkASSERT(elements.count() <= kMaxAnalyticElements);
SkSTArray<kMaxAnalyticElements, sk_sp<GrFragmentProcessor>> 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<GrFragmentProcessor> 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<GrTexture> 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<GrTexture> 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<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->makeDrawContext(SkBackingFit::kApprox,
reducedClip.width(),
reducedClip.height(),
config, nullptr));
if (!dc) {
return nullptr;
}
if (!reducedClip.drawAlphaClipMask(dc.get())) {
return nullptr;
}
sk_sp<GrTexture> texture(dc->asTexture());
SkASSERT(texture);
texture->resourcePriv().setUniqueKey(key);
return texture;
}
sk_sp<GrTexture> GrClipStackClip::CreateSoftwareClipMask(GrTextureProvider* texProvider,
const GrReducedClip& reducedClip) {
GrUniqueKey key;
GetClipMaskKey(reducedClip.elementsGenID(), reducedClip.ibounds(), &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(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<GrTexture> result(texProvider->createApproxTexture(desc));
if (!result) {
return nullptr;
}
result->resourcePriv().setUniqueKey(key);
helper.toTexture(result.get());
return result;
}