Files
test/source/blender/gpu/vulkan/vk_data_conversion.hh
2025-09-12 10:19:56 +10:00

230 lines
7.7 KiB
C++

/* SPDX-FileCopyrightText: 2023 Blender Authors
*
* SPDX-License-Identifier: GPL-2.0-or-later */
/** \file
* \ingroup gpu
*/
#pragma once
#include "BLI_math_vector_types.hh"
#include "gpu_texture_private.hh"
#include "vk_common.hh"
namespace blender::gpu {
struct VKWorkarounds;
/**
* Convert host buffer to device buffer.
*
* \param dst_buffer: device buffer.
* \param src_buffer: host buffer.
* \param buffer_size: number of pixels to convert from the start of the given buffer.
* \param host_format: format of the host buffer.
* \param host_texture_format: texture format of the host buffer.
* \param device_format: format of the device buffer.
*
* \note Will assert when the host_format/device_format combination isn't valid
* (#validate_data_format) or supported. Some combinations aren't supported in Vulkan due to
* platform incompatibility.
*/
void convert_host_to_device(void *dst_buffer,
const void *src_buffer,
size_t buffer_size,
eGPUDataFormat host_format,
TextureFormat host_texture_format,
TextureFormat device_format);
/**
* Convert device buffer to host buffer.
*
* \param dst_buffer: host buffer
* \param src_buffer: device buffer.
* \param buffer_size: number of pixels to convert from the start of the given buffer.
* \param host_format: format of the host buffer
* \param host_texture_format: texture format of the host buffer.
* \param device_format: format of the device buffer.
*
* \note Will assert when the host_format/device_format combination isn't valid
* (#validate_data_format) or supported. Some combinations aren't supported in Vulkan due to
* platform incompatibility.
*/
void convert_device_to_host(void *dst_buffer,
const void *src_buffer,
size_t buffer_size,
eGPUDataFormat host_format,
TextureFormat host_texture_format,
TextureFormat device_format);
/* -------------------------------------------------------------------- */
/** \name Floating point conversions
* \{ */
/**
* Description of a IEEE 754-1985 floating point data type.
*/
template<bool HasSignBit, uint8_t MantissaBitLen, uint8_t ExponentBitLen>
class FloatingPointFormat {
public:
static constexpr bool HAS_SIGN = HasSignBit;
static constexpr uint8_t SIGN_SHIFT = MantissaBitLen + ExponentBitLen;
static constexpr uint32_t SIGN_MASK = HasSignBit ? 1 : 0;
static constexpr uint8_t MANTISSA_LEN = MantissaBitLen;
static constexpr uint8_t MANTISSA_SHIFT = 0;
static constexpr uint32_t MANTISSA_MASK = (1 << MantissaBitLen) - 1;
static constexpr uint32_t MANTISSA_NAN_MASK = MANTISSA_MASK;
static constexpr uint8_t EXPONENT_SHIFT = MantissaBitLen;
static constexpr uint8_t EXPONENT_LEN = ExponentBitLen;
static constexpr uint32_t EXPONENT_MASK = (1 << ExponentBitLen) - 1;
static constexpr int32_t EXPONENT_BIAS = (1 << (ExponentBitLen - 1)) - 1;
static constexpr int32_t EXPONENT_SPECIAL_MASK = EXPONENT_MASK;
static uint32_t get_mantissa(uint32_t floating_point_number)
{
return (floating_point_number >> MANTISSA_SHIFT) & MANTISSA_MASK;
}
static uint32_t clear_mantissa(uint32_t floating_point_number)
{
return floating_point_number & ~(MANTISSA_MASK << MANTISSA_SHIFT);
}
static uint32_t set_mantissa(uint32_t mantissa, uint32_t floating_point_number)
{
uint32_t result = clear_mantissa(floating_point_number);
result |= mantissa << MANTISSA_SHIFT;
return result;
}
static uint32_t get_exponent(uint32_t floating_point_number)
{
return ((floating_point_number >> EXPONENT_SHIFT) & EXPONENT_MASK);
}
static uint32_t clear_exponent(uint32_t floating_point_number)
{
return floating_point_number & ~(EXPONENT_MASK << EXPONENT_SHIFT);
}
static uint32_t set_exponent(uint32_t exponent, uint32_t floating_point_number)
{
uint32_t result = clear_exponent(floating_point_number);
result |= (exponent) << EXPONENT_SHIFT;
return result;
}
static bool is_signed(uint32_t floating_point_number)
{
if constexpr (HasSignBit) {
return (floating_point_number >> SIGN_SHIFT) & SIGN_MASK;
}
return false;
}
static uint32_t clear_sign(uint32_t floating_point_number)
{
return floating_point_number & ~(1 << SIGN_SHIFT);
}
static uint32_t set_sign(bool sign, uint32_t floating_point_number)
{
if constexpr (!HasSignBit) {
return floating_point_number;
}
uint32_t result = clear_sign(floating_point_number);
result |= uint32_t(sign) << SIGN_SHIFT;
return result;
}
};
using FormatF32 = FloatingPointFormat<true, 23, 8>;
using FormatF11 = FloatingPointFormat<false, 6, 5>;
using FormatF10 = FloatingPointFormat<false, 5, 5>;
/**
* Convert between low precision floating (including 32 bit floats).
*
* The input and output values are bits (uint32_t) as this function does a bit-wise operations to
* convert between the formats. Additional conversion rules can be applied to the conversion
* function. Due to the implementation the compiler would make an optimized version depending on
* the actual possibilities.
*/
template<
/**
* FloatingPointFormat of the value that is converted to.
*/
typename DestinationFormat,
/**
* FloatingPointFormat of the value that is converted from.
*/
typename SourceFormat,
/**
* Should negative values be clamped to zero when DestinationFormat doesn't contain a sign
* bit. Also -Inf will be clamped to zero.
*
* When set to `false` and DestinationFormat doesn't contain a sign bit the value will be
* made absolute.
*/
bool ClampNegativeToZero = true>
uint32_t convert_float_formats(uint32_t value)
{
bool is_signed = SourceFormat::is_signed(value);
uint32_t mantissa = SourceFormat::get_mantissa(value);
int32_t exponent = SourceFormat::get_exponent(value);
const bool is_nan = (exponent == SourceFormat::EXPONENT_SPECIAL_MASK) && mantissa;
const bool is_inf = (exponent == SourceFormat::EXPONENT_SPECIAL_MASK) && (mantissa == 0);
const bool is_zero = (exponent == 0 && mantissa == 0);
/* Sign conversion */
if constexpr (!DestinationFormat::HAS_SIGN && ClampNegativeToZero) {
if (is_signed && !is_nan) {
return 0;
}
}
if (is_zero) {
return 0;
}
if (is_inf) {
exponent = DestinationFormat::EXPONENT_SPECIAL_MASK;
}
else if (is_nan) {
exponent = DestinationFormat::EXPONENT_SPECIAL_MASK;
mantissa = DestinationFormat::MANTISSA_NAN_MASK;
}
else {
/* Exponent conversion */
exponent -= SourceFormat::EXPONENT_BIAS;
/* Clamping when destination has lower precision. */
if constexpr (SourceFormat::EXPONENT_LEN > DestinationFormat::EXPONENT_LEN) {
if (exponent > DestinationFormat::EXPONENT_BIAS) {
exponent = 0;
mantissa = SourceFormat::MANTISSA_MASK;
}
else if (exponent < -DestinationFormat::EXPONENT_BIAS) {
return 0;
}
}
exponent += DestinationFormat::EXPONENT_BIAS;
/* Mantissa conversion */
if constexpr (SourceFormat::MANTISSA_LEN > DestinationFormat::MANTISSA_LEN) {
mantissa = mantissa >> (SourceFormat::MANTISSA_LEN - DestinationFormat::MANTISSA_LEN);
}
else if constexpr (SourceFormat::MANTISSA_LEN < DestinationFormat::MANTISSA_LEN) {
mantissa = mantissa << (DestinationFormat::MANTISSA_LEN - SourceFormat::MANTISSA_LEN);
}
}
uint32_t result = 0;
result = DestinationFormat::set_sign(is_signed, result);
result = DestinationFormat::set_exponent(exponent, result);
result = DestinationFormat::set_mantissa(mantissa, result);
return result;
}
/** \} */
}; // namespace blender::gpu