| Mike Reed | d6cb11e | 2017-11-30 15:33:04 -0500 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2017 Google Inc. |
| 3 | * |
| 4 | * Use of this source code is governed by a BSD-style license that can be |
| 5 | * found in the LICENSE file. |
| 6 | */ |
| 7 | |
| 8 | #ifndef SkPngPriv_DEFINED |
| 9 | #define SkPngPriv_DEFINED |
| 10 | |
| 11 | #include "SkTypes.h" |
| 12 | |
| 13 | // We store kAlpha_8 images as GrayAlpha in png. Our private signal is significant bits for gray. |
| 14 | // If that is set to 1, we assume the gray channel can be ignored, and we output just alpha. |
| 15 | // We tried 0 at first, but png doesn't like a 0 sigbit for a channel it expects, hence we chose 1. |
| 16 | |
| 17 | static constexpr int kGraySigBit_GrayAlphaIsJustAlpha = 1; |
| 18 | |
| 19 | #endif |