1*c8dee2aaSAndroid Build Coastguard Worker /* 2*c8dee2aaSAndroid Build Coastguard Worker * Copyright 2014 Google Inc. 3*c8dee2aaSAndroid Build Coastguard Worker * 4*c8dee2aaSAndroid Build Coastguard Worker * Use of this source code is governed by a BSD-style license that can be 5*c8dee2aaSAndroid Build Coastguard Worker * found in the LICENSE file. 6*c8dee2aaSAndroid Build Coastguard Worker */ 7*c8dee2aaSAndroid Build Coastguard Worker 8*c8dee2aaSAndroid Build Coastguard Worker #ifndef SkHalf_DEFINED 9*c8dee2aaSAndroid Build Coastguard Worker #define SkHalf_DEFINED 10*c8dee2aaSAndroid Build Coastguard Worker 11*c8dee2aaSAndroid Build Coastguard Worker #include <cstdint> 12*c8dee2aaSAndroid Build Coastguard Worker 13*c8dee2aaSAndroid Build Coastguard Worker // 16-bit floating point value 14*c8dee2aaSAndroid Build Coastguard Worker // format is 1 bit sign, 5 bits exponent, 10 bits mantissa 15*c8dee2aaSAndroid Build Coastguard Worker // only used for storage 16*c8dee2aaSAndroid Build Coastguard Worker using SkHalf = uint16_t; 17*c8dee2aaSAndroid Build Coastguard Worker 18*c8dee2aaSAndroid Build Coastguard Worker static constexpr uint16_t SK_HalfNaN = 0x7c01; // a NaN value, not all possible NaN values 19*c8dee2aaSAndroid Build Coastguard Worker static constexpr uint16_t SK_HalfInfinity = 0x7c00; 20*c8dee2aaSAndroid Build Coastguard Worker static constexpr uint16_t SK_HalfMin = 0x0400; // 2^-14 (minimum positive normal value) 21*c8dee2aaSAndroid Build Coastguard Worker static constexpr uint16_t SK_HalfMax = 0x7bff; // 65504 (maximum positive normal value) 22*c8dee2aaSAndroid Build Coastguard Worker static constexpr uint16_t SK_HalfEpsilon = 0x1400; // 2^-10 23*c8dee2aaSAndroid Build Coastguard Worker static constexpr uint16_t SK_Half1 = 0x3C00; // 1 24*c8dee2aaSAndroid Build Coastguard Worker 25*c8dee2aaSAndroid Build Coastguard Worker // Convert between half and single precision floating point. Vectorized functions 26*c8dee2aaSAndroid Build Coastguard Worker // skvx::from_half and skvx::to_half are also available. Unlike skvx::to_half, this will 27*c8dee2aaSAndroid Build Coastguard Worker // correctly handle float NaN -> half NaN. 28*c8dee2aaSAndroid Build Coastguard Worker float SkHalfToFloat(SkHalf h); 29*c8dee2aaSAndroid Build Coastguard Worker SkHalf SkFloatToHalf(float f); 30*c8dee2aaSAndroid Build Coastguard Worker 31*c8dee2aaSAndroid Build Coastguard Worker #endif 32