| // Copyright 2016 The SwiftShader Authors. All Rights Reserved. |
| // |
| // 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. |
| |
| #ifndef sw_Half_hpp |
| #define sw_Half_hpp |
| |
| namespace sw |
| { |
| class half |
| { |
| public: |
| half() = default; |
| explicit half(float f); |
| |
| operator float() const; |
| |
| half &operator=(half h); |
| half &operator=(float f); |
| |
| private: |
| unsigned short fp16i; |
| }; |
| |
| inline half shortAsHalf(short s) |
| { |
| union |
| { |
| half h; |
| short s; |
| } hs; |
| |
| hs.s = s; |
| |
| return hs.h; |
| } |
| |
| class RGB9E5 |
| { |
| unsigned int R : 9; |
| unsigned int G : 9; |
| unsigned int B : 9; |
| unsigned int E : 5; |
| |
| public: |
| void toRGB16F(half rgb[3]) const |
| { |
| constexpr int offset = 24; // Exponent bias (15) + number of mantissa bits per component (9) = 24 |
| |
| const float factor = (1u << E) * (1.0f / (1 << offset)); |
| rgb[0] = half(R * factor); |
| rgb[1] = half(G * factor); |
| rgb[2] = half(B * factor); |
| } |
| }; |
| |
| class R11G11B10F |
| { |
| unsigned int R : 11; |
| unsigned int G : 11; |
| unsigned int B : 10; |
| |
| static inline half float11ToFloat16(unsigned short fp11) |
| { |
| return shortAsHalf(fp11 << 4); // Sign bit 0 |
| } |
| |
| static inline half float10ToFloat16(unsigned short fp10) |
| { |
| return shortAsHalf(fp10 << 5); // Sign bit 0 |
| } |
| |
| public: |
| void toRGB16F(half rgb[3]) const |
| { |
| rgb[0] = float11ToFloat16(R); |
| rgb[1] = float11ToFloat16(G); |
| rgb[2] = float10ToFloat16(B); |
| } |
| }; |
| } |
| |
| #endif // sw_Half_hpp |