1 /*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "LayerDrawable.h"
18 #include <utils/MathUtils.h>
19
20 #include "GrBackendSurface.h"
21 #include "SkColorFilter.h"
22 #include "SkSurface.h"
23 #include "gl/GrGLTypes.h"
24
25 namespace android {
26 namespace uirenderer {
27 namespace skiapipeline {
28
onDraw(SkCanvas * canvas)29 void LayerDrawable::onDraw(SkCanvas* canvas) {
30 Layer* layer = mLayerUpdater->backingLayer();
31 if (layer) {
32 DrawLayer(canvas->getGrContext(), canvas, layer, nullptr, nullptr, true);
33 }
34 }
35
36 // This is a less-strict matrix.isTranslate() that will still report being translate-only
37 // on imperceptibly small scaleX & scaleY values.
isBasicallyTranslate(const SkMatrix & matrix)38 static bool isBasicallyTranslate(const SkMatrix& matrix) {
39 if (!matrix.isScaleTranslate()) return false;
40 return MathUtils::isOne(matrix.getScaleX()) && MathUtils::isOne(matrix.getScaleY());
41 }
42
shouldFilter(const SkMatrix & matrix)43 static bool shouldFilter(const SkMatrix& matrix) {
44 if (!matrix.isScaleTranslate()) return true;
45
46 // We only care about meaningful scale here
47 bool noScale = MathUtils::isOne(matrix.getScaleX()) && MathUtils::isOne(matrix.getScaleY());
48 bool pixelAligned =
49 SkScalarIsInt(matrix.getTranslateX()) && SkScalarIsInt(matrix.getTranslateY());
50 return !(noScale && pixelAligned);
51 }
52
DrawLayer(GrContext * context,SkCanvas * canvas,Layer * layer,const SkRect * srcRect,const SkRect * dstRect,bool useLayerTransform)53 bool LayerDrawable::DrawLayer(GrContext* context, SkCanvas* canvas, Layer* layer,
54 const SkRect* srcRect, const SkRect* dstRect,
55 bool useLayerTransform) {
56 if (context == nullptr) {
57 SkDEBUGF(("Attempting to draw LayerDrawable into an unsupported surface"));
58 return false;
59 }
60 // transform the matrix based on the layer
61 SkMatrix layerTransform = layer->getTransform();
62 sk_sp<SkImage> layerImage = layer->getImage();
63 const int layerWidth = layer->getWidth();
64 const int layerHeight = layer->getHeight();
65
66 if (layerImage) {
67 SkMatrix textureMatrixInv;
68 textureMatrixInv = layer->getTexTransform();
69 // TODO: after skia bug https://bugs.chromium.org/p/skia/issues/detail?id=7075 is fixed
70 // use bottom left origin and remove flipV and invert transformations.
71 SkMatrix flipV;
72 flipV.setAll(1, 0, 0, 0, -1, 1, 0, 0, 1);
73 textureMatrixInv.preConcat(flipV);
74 textureMatrixInv.preScale(1.0f / layerWidth, 1.0f / layerHeight);
75 textureMatrixInv.postScale(layerImage->width(), layerImage->height());
76 SkMatrix textureMatrix;
77 if (!textureMatrixInv.invert(&textureMatrix)) {
78 textureMatrix = textureMatrixInv;
79 }
80
81 SkMatrix matrix;
82 if (useLayerTransform) {
83 matrix = SkMatrix::Concat(layerTransform, textureMatrix);
84 } else {
85 matrix = textureMatrix;
86 }
87
88 SkPaint paint;
89 paint.setAlpha(layer->getAlpha());
90 paint.setBlendMode(layer->getMode());
91 paint.setColorFilter(layer->getColorFilter());
92 const bool nonIdentityMatrix = !matrix.isIdentity();
93 if (nonIdentityMatrix) {
94 canvas->save();
95 canvas->concat(matrix);
96 }
97 const SkMatrix& totalMatrix = canvas->getTotalMatrix();
98 if (dstRect || srcRect) {
99 SkMatrix matrixInv;
100 if (!matrix.invert(&matrixInv)) {
101 matrixInv = matrix;
102 }
103 SkRect skiaSrcRect;
104 if (srcRect) {
105 skiaSrcRect = *srcRect;
106 } else {
107 skiaSrcRect = SkRect::MakeIWH(layerWidth, layerHeight);
108 }
109 matrixInv.mapRect(&skiaSrcRect);
110 SkRect skiaDestRect;
111 if (dstRect) {
112 skiaDestRect = *dstRect;
113 } else {
114 skiaDestRect = SkRect::MakeIWH(layerWidth, layerHeight);
115 }
116 matrixInv.mapRect(&skiaDestRect);
117 // If (matrix is identity or an integer translation) and (src/dst buffers size match),
118 // then use nearest neighbor, otherwise use bilerp sampling.
119 // Integer translation is defined as when src rect and dst rect align fractionally.
120 // Skia TextureOp has the above logic build-in, but not NonAAFillRectOp. TextureOp works
121 // only for SrcOver blending and without color filter (readback uses Src blending).
122 bool isIntegerTranslate =
123 isBasicallyTranslate(totalMatrix) &&
124 SkScalarFraction(skiaDestRect.fLeft + totalMatrix[SkMatrix::kMTransX]) ==
125 SkScalarFraction(skiaSrcRect.fLeft) &&
126 SkScalarFraction(skiaDestRect.fTop + totalMatrix[SkMatrix::kMTransY]) ==
127 SkScalarFraction(skiaSrcRect.fTop);
128 if (layer->getForceFilter() || !isIntegerTranslate) {
129 paint.setFilterQuality(kLow_SkFilterQuality);
130 }
131 canvas->drawImageRect(layerImage.get(), skiaSrcRect, skiaDestRect, &paint,
132 SkCanvas::kFast_SrcRectConstraint);
133 } else {
134 if (layer->getForceFilter() || shouldFilter(totalMatrix)) {
135 paint.setFilterQuality(kLow_SkFilterQuality);
136 }
137 canvas->drawImage(layerImage.get(), 0, 0, &paint);
138 }
139 // restore the original matrix
140 if (nonIdentityMatrix) {
141 canvas->restore();
142 }
143 }
144
145 return layerImage != nullptr;
146 }
147
148 } // namespace skiapipeline
149 } // namespace uirenderer
150 } // namespace android
151