1 /* 2 * Copyright (C) 2013 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_BLUR_H 18 #define ANDROID_HWUI_BLUR_H 19 20 #include <cutils/compiler.h> 21 #include <stdint.h> 22 23 namespace android { 24 namespace uirenderer { 25 26 class Blur { 27 public: 28 // If radius > 0, return the corresponding sigma, else return 0 29 static float convertRadiusToSigma(float radius); 30 // If sigma > 0.5, return the corresponding radius, else return 0 31 static float convertSigmaToRadius(float sigma); 32 // If the original radius was on an integer boundary then after the sigma to 33 // radius conversion a small rounding error may be introduced. This function 34 // accounts for that error and snaps to the appropriate integer boundary. 35 static uint32_t convertRadiusToInt(float radius); 36 37 static void generateGaussianWeights(float* weights, float radius); 38 static void horizontal(float* weights, int32_t radius, const uint8_t* source, uint8_t* dest, 39 int32_t width, int32_t height); 40 static void vertical(float* weights, int32_t radius, const uint8_t* source, uint8_t* dest, 41 int32_t width, int32_t height); 42 }; 43 44 } // namespace uirenderer 45 } // namespace android 46 47 #endif // ANDROID_HWUI_BLUR_H 48