blob: f83eefe9d06b933315d3237fa261c500552a9e2b [file] [log] [blame]
* Copyright 2013 Google Inc.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
#include "include/effects/SkComposeImageFilter.h"
#include "src/core/SkImageFilter_Base.h"
#include "src/core/SkReadBuffer.h"
#include "src/core/SkSpecialImage.h"
#include "src/core/SkWriteBuffer.h"
namespace {
class SkComposeImageFilterImpl final : public SkImageFilter_Base {
explicit SkComposeImageFilterImpl(sk_sp<SkImageFilter> inputs[2])
: INHERITED(inputs, 2, nullptr) {
SkRect computeFastBounds(const SkRect& src) const override;
sk_sp<SkSpecialImage> onFilterImage(const Context&, SkIPoint* offset) const override;
SkIRect onFilterBounds(const SkIRect&, const SkMatrix& ctm,
MapDirection, const SkIRect* inputRect) const override;
bool onCanHandleComplexCTM() const override { return true; }
friend void SkComposeImageFilter::RegisterFlattenables();
typedef SkImageFilter_Base INHERITED;
} // end namespace
sk_sp<SkImageFilter> SkComposeImageFilter::Make(sk_sp<SkImageFilter> outer,
sk_sp<SkImageFilter> inner) {
if (!outer) {
return inner;
if (!inner) {
return outer;
sk_sp<SkImageFilter> inputs[2] = { std::move(outer), std::move(inner) };
return sk_sp<SkImageFilter>(new SkComposeImageFilterImpl(inputs));
void SkComposeImageFilter::RegisterFlattenables() {
// TODO (michaelludwig) - Remove after grace period for SKPs to stop using old name
SkFlattenable::Register("SkComposeImageFilter", SkComposeImageFilterImpl::CreateProc);
sk_sp<SkFlattenable> SkComposeImageFilterImpl::CreateProc(SkReadBuffer& buffer) {
return SkComposeImageFilter::Make(common.getInput(0), common.getInput(1));
SkRect SkComposeImageFilterImpl::computeFastBounds(const SkRect& src) const {
const SkImageFilter* outer = this->getInput(0);
const SkImageFilter* inner = this->getInput(1);
return outer->computeFastBounds(inner->computeFastBounds(src));
sk_sp<SkSpecialImage> SkComposeImageFilterImpl::onFilterImage(const Context& ctx,
SkIPoint* offset) const {
// The bounds passed to the inner filter must be filtered by the outer
// filter, so that the inner filter produces the pixels that the outer
// filter requires as input. This matters if the outer filter moves pixels.
SkIRect innerClipBounds;
innerClipBounds = this->getInput(0)->filterBounds(ctx.clipBounds(), ctx.ctm(),
kReverse_MapDirection, &ctx.clipBounds());
Context innerContext = ctx.withNewDesiredOutput(skif::LayerSpace<SkIRect>(innerClipBounds));
SkIPoint innerOffset = SkIPoint::Make(0, 0);
sk_sp<SkSpecialImage> inner(this->filterInput(1, innerContext, &innerOffset));
if (!inner) {
return nullptr;
// TODO (michaelludwig) - Once all filters are updated to process coordinate spaces more
// robustly, we can allow source images to have non-(0,0) origins, which will mean that the
// CTM/clipBounds modifications for the outerContext can go away.
SkMatrix outerMatrix(ctx.ctm());
outerMatrix.postTranslate(SkIntToScalar(-innerOffset.x()), SkIntToScalar(-innerOffset.y()));
SkIRect clipBounds = ctx.clipBounds();
clipBounds.offset(-innerOffset.x(), -innerOffset.y());
// NOTE: This is the only spot in image filtering where the source image of the context
// is not constant for the entire DAG evaluation. Given that the inner and outer DAG branches
// were already created, there's no alternative way for the leaf nodes of the outer DAG to
// get the results of the inner DAG. Overriding the source image of the context has the correct
// effect, but means that the source image is not fixed for the entire filter process.
Context outerContext(outerMatrix, clipBounds, ctx.cache(), ctx.colorType(), ctx.colorSpace(),
SkIPoint outerOffset = SkIPoint::Make(0, 0);
sk_sp<SkSpecialImage> outer(this->filterInput(0, outerContext, &outerOffset));
if (!outer) {
return nullptr;
*offset = innerOffset + outerOffset;
return outer;
SkIRect SkComposeImageFilterImpl::onFilterBounds(const SkIRect& src, const SkMatrix& ctm,
MapDirection dir, const SkIRect* inputRect) const {
const SkImageFilter* outer = this->getInput(0);
const SkImageFilter* inner = this->getInput(1);
const SkIRect innerRect = inner->filterBounds(src, ctm, dir, inputRect);
return outer->filterBounds(innerRect, ctm, dir,
kReverse_MapDirection == dir ? &innerRect : nullptr);