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 <stdint.h>
21#include <cutils/compiler.h>
22
23namespace android {
24namespace uirenderer {
25
26class Blur {
27public:
28    // If radius > 0, return the corresponding sigma, else return 0
29    ANDROID_API static float convertRadiusToSigma(float radius);
30    // If sigma > 0.5, return the corresponding radius, else return 0
31    ANDROID_API 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, int32_t radius);
38    static void horizontal(float* weights, int32_t radius, const uint8_t* source,
39        uint8_t* dest, int32_t width, int32_t height);
40    static void vertical(float* weights, int32_t radius, const uint8_t* source,
41        uint8_t* dest, int32_t width, int32_t height);
42};
43
44}; // namespace uirenderer
45}; // namespace android
46
47#endif // ANDROID_HWUI_BLUR_H
48