1 /*
2 * Copyright (C) 2012 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 "Layer.h"
18
19 #include "renderstate/RenderState.h"
20 #include "utils/Color.h"
21 #include "utils/MathUtils.h"
22
23 #include <SkBlendMode.h>
24
25 #include <log/log.h>
26
27 namespace android {
28 namespace uirenderer {
29
Layer(RenderState & renderState,sk_sp<SkColorFilter> colorFilter,int alpha,SkBlendMode mode)30 Layer::Layer(RenderState& renderState, sk_sp<SkColorFilter> colorFilter, int alpha,
31 SkBlendMode mode)
32 : mRenderState(renderState)
33 , mColorFilter(colorFilter)
34 , alpha(alpha)
35 , mode(mode) {
36 // TODO: This is a violation of Android's typical ref counting, but it
37 // preserves the old inc/dec ref locations. This should be changed...
38 incStrong(nullptr);
39 renderState.registerLayer(this);
40 transform.setIdentity();
41 }
42
~Layer()43 Layer::~Layer() {
44 mRenderState.unregisterLayer(this);
45 }
46
postDecStrong()47 void Layer::postDecStrong() {
48 mRenderState.postDecStrong(this);
49 }
50
getMode() const51 SkBlendMode Layer::getMode() const {
52 if (mBlend || mode != SkBlendMode::kSrcOver) {
53 return mode;
54 } else {
55 return SkBlendMode::kSrc;
56 }
57 }
58
isIntegerAligned(SkScalar x)59 static inline SkScalar isIntegerAligned(SkScalar x) {
60 return MathUtils::isZero(roundf(x) - x);
61 }
62
63 // Disable filtering when there is no scaling in screen coordinates and the corners have the same
64 // fraction (for translate) or zero fraction (for any other rect-to-rect transform).
shouldFilterRect(const SkMatrix & matrix,const SkRect & srcRect,const SkRect & dstRect)65 static bool shouldFilterRect(const SkMatrix& matrix, const SkRect& srcRect, const SkRect& dstRect) {
66 if (!matrix.rectStaysRect()) return true;
67 SkRect dstDevRect = matrix.mapRect(dstRect);
68 float dstW, dstH;
69 if (MathUtils::isZero(matrix.getScaleX()) && MathUtils::isZero(matrix.getScaleY())) {
70 // Has a 90 or 270 degree rotation, although total matrix may also have scale factors
71 // in m10 and m01. Those scalings are automatically handled by mapRect so comparing
72 // dimensions is sufficient, but swap width and height comparison.
73 dstW = dstDevRect.height();
74 dstH = dstDevRect.width();
75 } else {
76 // Handle H/V flips or 180 rotation matrices. Axes may have been mirrored, but
77 // dimensions are still safe to compare directly.
78 dstW = dstDevRect.width();
79 dstH = dstDevRect.height();
80 }
81 if (!(MathUtils::areEqual(dstW, srcRect.width()) &&
82 MathUtils::areEqual(dstH, srcRect.height()))) {
83 return true;
84 }
85 // Device rect and source rect should be integer aligned to ensure there's no difference
86 // in how nearest-neighbor sampling is resolved.
87 return !(isIntegerAligned(srcRect.x()) &&
88 isIntegerAligned(srcRect.y()) &&
89 isIntegerAligned(dstDevRect.x()) &&
90 isIntegerAligned(dstDevRect.y()));
91 }
92
draw(SkCanvas * canvas)93 void Layer::draw(SkCanvas* canvas) {
94 GrRecordingContext* context = canvas->recordingContext();
95 if (context == nullptr) {
96 ALOGD("Attempting to draw LayerDrawable into an unsupported surface");
97 return;
98 }
99 SkMatrix layerTransform = getTransform();
100 //sk_sp<SkImage> layerImage = getImage();
101 const int layerWidth = getWidth();
102 const int layerHeight = getHeight();
103 if (layerImage) {
104 SkMatrix textureMatrixInv;
105 // TODO: after skia bug https://bugs.chromium.org/p/skia/issues/detail?id=7075 is fixed
106 // use bottom left origin and remove flipV and invert transformations.
107 SkMatrix flipV;
108 flipV.setAll(1, 0, 0, 0, -1, 1, 0, 0, 1);
109 textureMatrixInv.preConcat(flipV);
110 textureMatrixInv.preScale(1.0f / layerWidth, 1.0f / layerHeight);
111 textureMatrixInv.postScale(layerImage->width(), layerImage->height());
112 SkMatrix textureMatrix;
113 if (!textureMatrixInv.invert(&textureMatrix)) {
114 textureMatrix = textureMatrixInv;
115 }
116
117 SkMatrix matrix;
118 matrix = SkMatrix::Concat(layerTransform, textureMatrix);
119
120 SkPaint paint;
121 paint.setAlpha(getAlpha());
122 paint.setBlendMode(getMode());
123 paint.setColorFilter(getColorFilter());
124 const bool nonIdentityMatrix = !matrix.isIdentity();
125 if (nonIdentityMatrix) {
126 canvas->save();
127 canvas->concat(matrix);
128 }
129 const SkMatrix& totalMatrix = canvas->getTotalMatrix();
130
131 SkRect imageRect = SkRect::MakeIWH(layerImage->width(), layerImage->height());
132 SkSamplingOptions sampling;
133 if (getForceFilter() || shouldFilterRect(totalMatrix, imageRect, imageRect)) {
134 sampling = SkSamplingOptions(SkFilterMode::kLinear);
135 }
136 canvas->drawImage(layerImage.get(), 0, 0, sampling, &paint);
137 // restore the original matrix
138 if (nonIdentityMatrix) {
139 canvas->restore();
140 }
141 }
142 }
143
144 } // namespace uirenderer
145 } // namespace android
146