1*c8dee2aaSAndroid Build Coastguard Worker /* 2*c8dee2aaSAndroid Build Coastguard Worker * Copyright 2017 Google Inc. 3*c8dee2aaSAndroid Build Coastguard Worker * 4*c8dee2aaSAndroid Build Coastguard Worker * Use of this source code is governed by a BSD-style license that can be 5*c8dee2aaSAndroid Build Coastguard Worker * found in the LICENSE file. 6*c8dee2aaSAndroid Build Coastguard Worker */ 7*c8dee2aaSAndroid Build Coastguard Worker 8*c8dee2aaSAndroid Build Coastguard Worker #ifndef SkPngPriv_DEFINED 9*c8dee2aaSAndroid Build Coastguard Worker #define SkPngPriv_DEFINED 10*c8dee2aaSAndroid Build Coastguard Worker 11*c8dee2aaSAndroid Build Coastguard Worker #include "include/core/SkTypes.h" 12*c8dee2aaSAndroid Build Coastguard Worker 13*c8dee2aaSAndroid Build Coastguard Worker // We store kAlpha_8 images as GrayAlpha in png. Our private signal is significant bits for gray. 14*c8dee2aaSAndroid Build Coastguard Worker // If that is set to 1, we assume the gray channel can be ignored, and we output just alpha. 15*c8dee2aaSAndroid Build Coastguard Worker // We tried 0 at first, but png doesn't like a 0 sigbit for a channel it expects, hence we chose 1. 16*c8dee2aaSAndroid Build Coastguard Worker 17*c8dee2aaSAndroid Build Coastguard Worker static constexpr int kGraySigBit_GrayAlphaIsJustAlpha = 1; 18*c8dee2aaSAndroid Build Coastguard Worker 19*c8dee2aaSAndroid Build Coastguard Worker #endif 20