/* * Copyright 2015 The Etc2Comp Authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #pragma once #include <math.h> namespace Etc { inline float LogToLinear(float a_fLog) { static const float ALPHA = 0.055f; static const float ONE_PLUS_ALPHA = 1.0f + ALPHA; if (a_fLog <= 0.04045f) { return a_fLog / 12.92f; } else { return powf((a_fLog + ALPHA) / ONE_PLUS_ALPHA, 2.4f); } } inline float LinearToLog(float &a_fLinear) { static const float ALPHA = 0.055f; static const float ONE_PLUS_ALPHA = 1.0f + ALPHA; if (a_fLinear <= 0.0031308f) { return 12.92f * a_fLinear; } else { return ONE_PLUS_ALPHA * powf(a_fLinear, (1.0f/2.4f)) - ALPHA; } } class ColorR8G8B8A8 { public: unsigned char ucR; unsigned char ucG; unsigned char ucB; unsigned char ucA; }; }