/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "LayerDrawable.h"
#include <utils/MathUtils.h>
#include "GrBackendSurface.h"
#include "SkColorFilter.h"
#include "SkSurface.h"
#include "gl/GrGLTypes.h"
namespace android {
namespace uirenderer {
namespace skiapipeline {
void LayerDrawable::onDraw(SkCanvas* canvas) {
Layer* layer = mLayerUpdater->backingLayer();
if (layer) {
DrawLayer(canvas->getGrContext(), canvas, layer, nullptr, nullptr, true);
}
}
// This is a less-strict matrix.isTranslate() that will still report being translate-only
// on imperceptibly small scaleX & scaleY values.
static bool isBasicallyTranslate(const SkMatrix& matrix) {
if (!matrix.isScaleTranslate()) return false;
return MathUtils::isOne(matrix.getScaleX()) && MathUtils::isOne(matrix.getScaleY());
}
static bool shouldFilter(const SkMatrix& matrix) {
if (!matrix.isScaleTranslate()) return true;
// We only care about meaningful scale here
bool noScale = MathUtils::isOne(matrix.getScaleX()) && MathUtils::isOne(matrix.getScaleY());
bool pixelAligned =
SkScalarIsInt(matrix.getTranslateX()) && SkScalarIsInt(matrix.getTranslateY());
return !(noScale && pixelAligned);
}
bool LayerDrawable::DrawLayer(GrContext* context, SkCanvas* canvas, Layer* layer,
const SkRect* srcRect, const SkRect* dstRect,
bool useLayerTransform) {
if (context == nullptr) {
SkDEBUGF(("Attempting to draw LayerDrawable into an unsupported surface"));
return false;
}
// transform the matrix based on the layer
SkMatrix layerTransform = layer->getTransform();
sk_sp<SkImage> layerImage = layer->getImage();
const int layerWidth = layer->getWidth();
const int layerHeight = layer->getHeight();
if (layerImage) {
SkMatrix textureMatrixInv;
textureMatrixInv = layer->getTexTransform();
// TODO: after skia bug https://bugs.chromium.org/p/skia/issues/detail?id=7075 is fixed
// use bottom left origin and remove flipV and invert transformations.
SkMatrix flipV;
flipV.setAll(1, 0, 0, 0, -1, 1, 0, 0, 1);
textureMatrixInv.preConcat(flipV);
textureMatrixInv.preScale(1.0f / layerWidth, 1.0f / layerHeight);
textureMatrixInv.postScale(layerImage->width(), layerImage->height());
SkMatrix textureMatrix;
if (!textureMatrixInv.invert(&textureMatrix)) {
textureMatrix = textureMatrixInv;
}
SkMatrix matrix;
if (useLayerTransform) {
matrix = SkMatrix::Concat(layerTransform, textureMatrix);
} else {
matrix = textureMatrix;
}
SkPaint paint;
paint.setAlpha(layer->getAlpha());
paint.setBlendMode(layer->getMode());
paint.setColorFilter(layer->getColorFilter());
const bool nonIdentityMatrix = !matrix.isIdentity();
if (nonIdentityMatrix) {
canvas->save();
canvas->concat(matrix);
}
const SkMatrix& totalMatrix = canvas->getTotalMatrix();
if (dstRect || srcRect) {
SkMatrix matrixInv;
if (!matrix.invert(&matrixInv)) {
matrixInv = matrix;
}
SkRect skiaSrcRect;
if (srcRect) {
skiaSrcRect = *srcRect;
} else {
skiaSrcRect = SkRect::MakeIWH(layerWidth, layerHeight);
}
matrixInv.mapRect(&skiaSrcRect);
SkRect skiaDestRect;
if (dstRect) {
skiaDestRect = *dstRect;
} else {
skiaDestRect = SkRect::MakeIWH(layerWidth, layerHeight);
}
matrixInv.mapRect(&skiaDestRect);
// If (matrix is identity or an integer translation) and (src/dst buffers size match),
// then use nearest neighbor, otherwise use bilerp sampling.
// Integer translation is defined as when src rect and dst rect align fractionally.
// Skia TextureOp has the above logic build-in, but not NonAAFillRectOp. TextureOp works
// only for SrcOver blending and without color filter (readback uses Src blending).
bool isIntegerTranslate =
isBasicallyTranslate(totalMatrix) &&
SkScalarFraction(skiaDestRect.fLeft + totalMatrix[SkMatrix::kMTransX]) ==
SkScalarFraction(skiaSrcRect.fLeft) &&
SkScalarFraction(skiaDestRect.fTop + totalMatrix[SkMatrix::kMTransY]) ==
SkScalarFraction(skiaSrcRect.fTop);
if (layer->getForceFilter() || !isIntegerTranslate) {
paint.setFilterQuality(kLow_SkFilterQuality);
}
canvas->drawImageRect(layerImage.get(), skiaSrcRect, skiaDestRect, &paint,
SkCanvas::kFast_SrcRectConstraint);
} else {
if (layer->getForceFilter() || shouldFilter(totalMatrix)) {
paint.setFilterQuality(kLow_SkFilterQuality);
}
canvas->drawImage(layerImage.get(), 0, 0, &paint);
}
// restore the original matrix
if (nonIdentityMatrix) {
canvas->restore();
}
}
return layerImage != nullptr;
}
} // namespace skiapipeline
} // namespace uirenderer
} // namespace android