Home | History | Annotate | Download | only in hwui
      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 #ifndef ANDROID_HWUI_DITHER_H
     18 #define ANDROID_HWUI_DITHER_H
     19 
     20 #include <GLES3/gl3.h>
     21 
     22 namespace android {
     23 namespace uirenderer {
     24 
     25 class Caches;
     26 class Extensions;
     27 class Program;
     28 
     29 // Must be a power of two
     30 #define DITHER_KERNEL_SIZE 4
     31 // These must not use the .0f notation as they are used from GLSL
     32 #define DITHER_KERNEL_SIZE_INV (1.0 / 4.0)
     33 #define DITHER_KERNEL_SIZE_INV_SQUARE (1.0 / 16.0)
     34 
     35 /**
     36  * Handles dithering for programs.
     37  */
     38 class Dither {
     39 public:
     40     Dither(Caches& caches);
     41 
     42     void clear();
     43     void setupProgram(Program& program, GLuint* textureUnit);
     44 
     45 private:
     46     void bindDitherTexture();
     47 
     48     Caches& mCaches;
     49     bool mInitialized;
     50     GLuint mDitherTexture;
     51 };
     52 
     53 }; // namespace uirenderer
     54 }; // namespace android
     55 
     56 #endif // ANDROID_HWUI_DITHER_H
     57