1 /**
2 * Copyright (C) 2023 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 #include "Gainmap.h"
17
18 #include <SkBitmap.h>
19 #include <SkCanvas.h>
20 #include <SkColorFilter.h>
21 #include <SkImagePriv.h>
22 #include <SkPaint.h>
23
24 #include "HardwareBitmapUploader.h"
25
26 namespace android::uirenderer {
27
allocateHardwareGainmap(const sp<Gainmap> & srcGainmap)28 sp<Gainmap> Gainmap::allocateHardwareGainmap(const sp<Gainmap>& srcGainmap) {
29 auto gainmap = sp<Gainmap>::make();
30 gainmap->info = srcGainmap->info;
31 SkBitmap skSrcBitmap = srcGainmap->bitmap->getSkBitmap();
32 if (skSrcBitmap.info().colorType() == kAlpha_8_SkColorType &&
33 !HardwareBitmapUploader::hasAlpha8Support()) {
34 // The regular Bitmap::allocateHardwareBitmap will do a conversion that preserves channels,
35 // so alpha8 maps to the alpha channel of rgba. However, for gainmaps we will interpret
36 // the data of an rgba buffer differently as we'll only look at the rgb channels
37 // So we need to map alpha8 to rgbx_8888 essentially
38 SkBitmap bitmap;
39 bitmap.allocPixels(skSrcBitmap.info().makeColorType(kN32_SkColorType));
40 SkCanvas canvas(bitmap);
41 SkPaint paint;
42 const float alphaToOpaque[] = {0, 0, 0, 1, 0, 0, 0, 0, 1, 0,
43 0, 0, 0, 1, 0, 0, 0, 0, 0, 255};
44 paint.setColorFilter(SkColorFilters::Matrix(alphaToOpaque, SkColorFilters::Clamp::kNo));
45 canvas.drawImage(SkMakeImageFromRasterBitmap(skSrcBitmap, kNever_SkCopyPixelsMode), 0, 0,
46 SkSamplingOptions{}, &paint);
47 skSrcBitmap = bitmap;
48 }
49 sk_sp<Bitmap> skBitmap(Bitmap::allocateHardwareBitmap(skSrcBitmap));
50 if (!skBitmap.get()) {
51 return nullptr;
52 }
53 gainmap->bitmap = std::move(skBitmap);
54 return gainmap;
55 }
56
57 } // namespace android::uirenderer