1 | // Copyright 2016 The SwiftShader Authors. All Rights Reserved. |
2 | // |
3 | // Licensed under the Apache License, Version 2.0 (the "License"); |
4 | // you may not use this file except in compliance with the License. |
5 | // You may obtain a copy of the License at |
6 | // |
7 | // http://www.apache.org/licenses/LICENSE-2.0 |
8 | // |
9 | // Unless required by applicable law or agreed to in writing, software |
10 | // distributed under the License is distributed on an "AS IS" BASIS, |
11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
12 | // See the License for the specific language governing permissions and |
13 | // limitations under the License. |
14 | |
15 | #include "Math.hpp" |
16 | |
17 | namespace sw |
18 | { |
19 | inline uint64_t FNV_1a(uint64_t hash, unsigned char data) |
20 | { |
21 | return (hash ^ data) * 1099511628211; |
22 | } |
23 | |
24 | uint64_t FNV_1a(const unsigned char *data, int size) |
25 | { |
26 | int64_t hash = 0xCBF29CE484222325; |
27 | |
28 | for(int i = 0; i < size; i++) |
29 | { |
30 | hash = FNV_1a(hash, data[i]); |
31 | } |
32 | |
33 | return hash; |
34 | } |
35 | |
36 | unsigned char sRGB8toLinear8(unsigned char value) |
37 | { |
38 | static unsigned char sRGBtoLinearTable[256] = { 255 }; |
39 | if(sRGBtoLinearTable[0] == 255) |
40 | { |
41 | for(int i = 0; i < 256; i++) |
42 | { |
43 | sRGBtoLinearTable[i] = static_cast<unsigned char>(sw::sRGBtoLinear(static_cast<float>(i) / 255.0f) * 255.0f + 0.5f); |
44 | } |
45 | } |
46 | |
47 | return sRGBtoLinearTable[value]; |
48 | } |
49 | } |
50 | |