diff options
| -rw-r--r-- | alc/alu.cpp | 107 |
1 files changed, 23 insertions, 84 deletions
diff --git a/alc/alu.cpp b/alc/alu.cpp index dcd3c7d2..f55c196d 100644 --- a/alc/alu.cpp +++ b/alc/alu.cpp @@ -341,95 +341,34 @@ inline uint dither_rng(uint *seed) noexcept } -/* Ambisonic upsampler functions. These are effectively matrix multiply - * operations. They take the 'coeffs' as the input matrix, and combine it with - * an "upsampler" matrix, resulting in a coefficient matrix that behaves as if - * the initial coefficients were applied to the B-Format input, which was then - * decoded to a speaker array at its input order, and finally encoded back into - * the higher order mix. +/* Ambisonic upsampler function. It's effectively a matrix multiply. It takes + * an 'upsampler' and 'rotator' as the input matrices, resulting in a matrix + * that behaves as if the B-Format input was first decoded to a speaker array + * at its input order, encoded back into the higher order mix, then finally + * rotated. */ -void UpsampleFirstOrder(const al::span<std::array<float,MaxAmbiChannels>,MaxAmbiChannels> coeffs) +template<size_t N> +void UpsampleBFormatTransform(size_t coeffs_order, + const std::array<std::array<float,MaxAmbiChannels>,N> &matrix1, + const al::span<std::array<float,MaxAmbiChannels>,MaxAmbiChannels> coeffs) { - auto transpose = [coeffs]() noexcept + auto copy_coeffs = [coeffs]() noexcept { - std::array<std::array<float,4>,4> res{}; - for(size_t i{0};i < 4;++i) - { - for(size_t j{0};j < 4;++j) - res[i][j] = coeffs[j][i]; - } - return res; - }; - const auto input = transpose(); - - static_assert(input[0].size() == AmbiScale::FirstOrderUp.size(), - "Mismatched first-order input and upsampler size"); - - for(size_t i{0};i < input.size();++i) - { - for(size_t j{0};j < AmbiScale::FirstOrderUp[0].size();++j) - { - double sum{0.0}; - for(size_t k{0};k < input[0].size();++k) - sum += double{input[i][k]} * AmbiScale::FirstOrderUp[k][j]; - coeffs[j][i] = static_cast<float>(sum); - } - } -} - -void UpsampleSecondOrder(const al::span<std::array<float,MaxAmbiChannels>,MaxAmbiChannels> coeffs) -{ - auto transpose = [coeffs]() noexcept - { - std::array<std::array<float,9>,9> res{}; - for(size_t i{0};i < 9;++i) - { - for(size_t j{0};j < 9;++j) - res[i][j] = coeffs[j][i]; - } + std::array<std::array<float,MaxAmbiChannels>,MaxAmbiChannels> res{}; + for(size_t i{0};i < MaxAmbiChannels;++i) + res[i] = coeffs[i]; return res; }; - const auto input = transpose(); - - static_assert(input[0].size() == AmbiScale::SecondOrderUp.size(), - "Mismatched second-order input and upsampler size"); - - for(size_t i{0};i < input.size();++i) - { - for(size_t j{0};j < AmbiScale::SecondOrderUp[0].size();++j) - { - double sum{0.0}; - for(size_t k{0};k < input[0].size();++k) - sum += double{input[i][k]} * AmbiScale::SecondOrderUp[k][j]; - coeffs[j][i] = static_cast<float>(sum); - } - } -} - -void UpsampleThirdOrder(const al::span<std::array<float,MaxAmbiChannels>,MaxAmbiChannels> coeffs) -{ - auto transpose = [coeffs]() noexcept - { - std::array<std::array<float,16>,16> res{}; - for(size_t i{0};i < 16;++i) - { - for(size_t j{0};j < 16;++j) - res[i][j] = coeffs[j][i]; - } - return res; - }; - const auto input = transpose(); - - static_assert(input[0].size() == AmbiScale::ThirdOrderUp.size(), - "Mismatched third-order input and upsampler size"); + const auto matrix2 = copy_coeffs(); - for(size_t i{0};i < input.size();++i) + const size_t num_chans{AmbiChannelsFromOrder(coeffs_order)}; + for(size_t i{0};i < matrix1.size();++i) { - for(size_t j{0};j < AmbiScale::ThirdOrderUp[0].size();++j) + for(size_t j{0};j < num_chans;++j) { double sum{0.0}; - for(size_t k{0};k < input[0].size();++k) - sum += double{input[i][k]} * AmbiScale::ThirdOrderUp[k][j]; + for(size_t k{0};k < num_chans;++k) + sum += double{matrix1[i][k]} * matrix2[j][k]; coeffs[j][i] = static_cast<float>(sum); } } @@ -966,16 +905,16 @@ void CalcPanningAndFilters(Voice *voice, const float xpos, const float ypos, con shrot[1][1] = U[0]; shrot[1][2] = -V[0]; shrot[1][3] = -N[0]; shrot[2][1] = -U[1]; shrot[2][2] = V[1]; shrot[2][3] = N[1]; shrot[3][1] = U[2]; shrot[3][2] = -V[2]; shrot[3][3] = -N[2]; - AmbiRotator(shrot, static_cast<int>(minu(voice->mAmbiOrder, Device->mAmbiOrder))); + AmbiRotator(shrot, static_cast<int>(Device->mAmbiOrder)); /* If the device is higher order than the voice, "upsample" the matrix */ if(Device->mAmbiOrder > voice->mAmbiOrder) { if(voice->mAmbiOrder == 1) - UpsampleFirstOrder(shrot); + UpsampleBFormatTransform(Device->mAmbiOrder, AmbiScale::FirstOrderUp, shrot); else if(voice->mAmbiOrder == 2) - UpsampleSecondOrder(shrot); + UpsampleBFormatTransform(Device->mAmbiOrder, AmbiScale::SecondOrderUp, shrot); else if(voice->mAmbiOrder == 3) - UpsampleThirdOrder(shrot); + UpsampleBFormatTransform(Device->mAmbiOrder, AmbiScale::ThirdOrderUp, shrot); } /* Convert the rotation matrix for input ordering and scaling, and |