| /* |
| * Copyright 2013 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef SkAlpha_DEFINED |
| #define SkAlpha_DEFINED |
| |
| #include "SkTypes.h" |
| |
| /** |
| * Describes how to interpret the alpha compoent of a pixel. |
| */ |
| enum SkAlphaType { |
| /** |
| * All pixels should be treated as opaque, regardless of the value stored |
| * in their alpha field. Used for legacy images that wrote 0 or garbarge |
| * in their alpha field, but intended the RGB to be treated as opaque. |
| */ |
| kIgnore_SkAlphaType, |
| |
| /** |
| * All pixels are stored as opaque. This differs slightly from kIgnore in |
| * that kOpaque has correct "opaque" values stored in the pixels, while |
| * kIgnore may not, but in both cases the caller should treat the pixels |
| * as opaque. |
| */ |
| kOpaque_SkAlphaType, |
| |
| /** |
| * All pixels have their alpha premultiplied in their color components. |
| * This is the natural format for the rendering target pixels. |
| */ |
| kPremul_SkAlphaType, |
| |
| /** |
| * All pixels have their color components stored without any regard to the |
| * alpha. e.g. this is the default configuration for PNG images. |
| * |
| * This alpha-type is ONLY supported for input images. Rendering cannot |
| * generate this on output. |
| */ |
| kUnpremul_SkAlphaType, |
| |
| kLastEnum_SkAlphaType = kUnpremul_SkAlphaType |
| }; |
| |
| static inline bool SkAlphaTypeIsOpaque(SkAlphaType at) { |
| return (unsigned)at <= kOpaque_SkAlphaType; |
| } |
| #endif |