tor-browser

copyvertex.inc.h (23236B)

---

//
// Copyright 2014 The ANGLE Project Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//

// copyvertex.inc.h: Implementation of vertex buffer copying and conversion functions

namespace rx
{

// Returns an aligned buffer to read the input from
template <typename T, size_t inputComponentCount>
inline const T *GetAlignedOffsetInput(const T *offsetInput, T *alignedElement)
{
   if (reinterpret_cast<uintptr_t>(offsetInput) % sizeof(T) != 0)
   {
       // Applications may pass in arbitrarily aligned buffers as input.
       // Certain architectures have restrictions regarding unaligned reads. Specifically, we crash
       // on armeabi-v7a devices with a SIGBUS error when performing such operations. arm64 and
       // x86-64 devices do not appear to have such issues.
       //
       // The workaround is to detect if the input buffer is unaligned and if so, perform a
       // byte-wise copy of the unaligned portion and a memcpy of the rest of the buffer.
       uint8_t *alignedBuffer               = reinterpret_cast<uint8_t *>(&alignedElement[0]);
       uintptr_t unalignedInputStartAddress = reinterpret_cast<uintptr_t>(offsetInput);
       constexpr size_t kAlignmentMinusOne  = sizeof(T) - 1;
       uintptr_t alignedInputStartAddress =
           (reinterpret_cast<uintptr_t>(offsetInput) + kAlignmentMinusOne) & ~(kAlignmentMinusOne);
       ASSERT(alignedInputStartAddress >= unalignedInputStartAddress);

       const size_t totalBytesToCopy     = sizeof(T) * inputComponentCount;
       const size_t unalignedBytesToCopy = alignedInputStartAddress - unalignedInputStartAddress;
       ASSERT(totalBytesToCopy >= unalignedBytesToCopy);

       // byte-wise copy of unaligned portion
       for (size_t i = 0; i < unalignedBytesToCopy; i++)
       {
           alignedBuffer[i] = reinterpret_cast<const uint8_t *>(&offsetInput[0])[i];
       }

       // memcpy remaining buffer
       memcpy(&alignedBuffer[unalignedBytesToCopy],
              &reinterpret_cast<const uint8_t *>(&offsetInput[0])[unalignedBytesToCopy],
              totalBytesToCopy - unalignedBytesToCopy);

       return alignedElement;
   }
   else
   {
       return offsetInput;
   }
}

template <typename T,
         size_t inputComponentCount,
         size_t outputComponentCount,
         uint32_t alphaDefaultValueBits>
inline void CopyNativeVertexData(const uint8_t *input, size_t stride, size_t count, uint8_t *output)
{
   const size_t attribSize = sizeof(T) * inputComponentCount;

   if (attribSize == stride && inputComponentCount == outputComponentCount)
   {
       memcpy(output, input, count * attribSize);
       return;
   }

   if (inputComponentCount == outputComponentCount)
   {
       for (size_t i = 0; i < count; i++)
       {
           const T *offsetInput = reinterpret_cast<const T *>(input + (i * stride));
           T offsetInputAligned[inputComponentCount];
           offsetInput =
               GetAlignedOffsetInput<T, inputComponentCount>(offsetInput, &offsetInputAligned[0]);

           T *offsetOutput = reinterpret_cast<T *>(output) + i * outputComponentCount;

           memcpy(offsetOutput, offsetInput, attribSize);
       }
       return;
   }

   const T defaultAlphaValue                = gl::bitCast<T>(alphaDefaultValueBits);
   const size_t lastNonAlphaOutputComponent = std::min<size_t>(outputComponentCount, 3);

   for (size_t i = 0; i < count; i++)
   {
       const T *offsetInput = reinterpret_cast<const T *>(input + (i * stride));
       T offsetInputAligned[inputComponentCount];
       ASSERT(sizeof(offsetInputAligned) == attribSize);
       offsetInput =
           GetAlignedOffsetInput<T, inputComponentCount>(offsetInput, &offsetInputAligned[0]);

       T *offsetOutput = reinterpret_cast<T *>(output) + i * outputComponentCount;

       memcpy(offsetOutput, offsetInput, attribSize);

       if (inputComponentCount < lastNonAlphaOutputComponent)
       {
           // Set the remaining G/B channels to 0.
           size_t numComponents = (lastNonAlphaOutputComponent - inputComponentCount);
           memset(&offsetOutput[inputComponentCount], 0, numComponents * sizeof(T));
       }

       if (inputComponentCount < outputComponentCount && outputComponentCount == 4)
       {
           // Set the remaining alpha channel to the defaultAlphaValue.
           offsetOutput[3] = defaultAlphaValue;
       }
   }
}

template <size_t inputComponentCount, size_t outputComponentCount>
inline void Copy8SintTo16SintVertexData(const uint8_t *input,
                                       size_t stride,
                                       size_t count,
                                       uint8_t *output)
{
   const size_t lastNonAlphaOutputComponent = std::min<size_t>(outputComponentCount, 3);

   for (size_t i = 0; i < count; i++)
   {
       const GLbyte *offsetInput = reinterpret_cast<const GLbyte *>(input + i * stride);
       GLshort *offsetOutput     = reinterpret_cast<GLshort *>(output) + i * outputComponentCount;

       for (size_t j = 0; j < inputComponentCount; j++)
       {
           offsetOutput[j] = static_cast<GLshort>(offsetInput[j]);
       }

       for (size_t j = inputComponentCount; j < lastNonAlphaOutputComponent; j++)
       {
           // Set remaining G/B channels to 0.
           offsetOutput[j] = 0;
       }

       if (inputComponentCount < outputComponentCount && outputComponentCount == 4)
       {
           // On integer formats, we must set the Alpha channel to 1 if it's unused.
           offsetOutput[3] = 1;
       }
   }
}

template <size_t inputComponentCount, size_t outputComponentCount>
inline void Copy8SnormTo16SnormVertexData(const uint8_t *input,
                                         size_t stride,
                                         size_t count,
                                         uint8_t *output)
{
   for (size_t i = 0; i < count; i++)
   {
       const GLbyte *offsetInput = reinterpret_cast<const GLbyte *>(input + i * stride);
       GLshort *offsetOutput     = reinterpret_cast<GLshort *>(output) + i * outputComponentCount;

       for (size_t j = 0; j < inputComponentCount; j++)
       {
           // The original GLbyte value ranges from -128 to +127 (INT8_MAX).
           // When converted to GLshort, the value must be scaled to between -32768 and +32767
           // (INT16_MAX).
           if (offsetInput[j] > 0)
           {
               offsetOutput[j] =
                   offsetInput[j] << 8 | offsetInput[j] << 1 | ((offsetInput[j] & 0x40) >> 6);
           }
           else
           {
               offsetOutput[j] = offsetInput[j] << 8;
           }
       }

       for (size_t j = inputComponentCount; j < std::min<size_t>(outputComponentCount, 3); j++)
       {
           // Set remaining G/B channels to 0.
           offsetOutput[j] = 0;
       }

       if (inputComponentCount < outputComponentCount && outputComponentCount == 4)
       {
           // On normalized formats, we must set the Alpha channel to the max value if it's unused.
           offsetOutput[3] = INT16_MAX;
       }
   }
}

template <size_t inputComponentCount, size_t outputComponentCount>
inline void Copy32FixedTo32FVertexData(const uint8_t *input,
                                      size_t stride,
                                      size_t count,
                                      uint8_t *output)
{
   static const float divisor = 1.0f / (1 << 16);

   for (size_t i = 0; i < count; i++)
   {
       const uint8_t *offsetInput = input + i * stride;
       float *offsetOutput        = reinterpret_cast<float *>(output) + i * outputComponentCount;

       // GLfixed access must be 4-byte aligned on arm32, input and stride sometimes are not
       if (reinterpret_cast<uintptr_t>(offsetInput) % sizeof(GLfixed) == 0)
       {
           for (size_t j = 0; j < inputComponentCount; j++)
           {
               offsetOutput[j] =
                   static_cast<float>(reinterpret_cast<const GLfixed *>(offsetInput)[j]) * divisor;
           }
       }
       else
       {
           for (size_t j = 0; j < inputComponentCount; j++)
           {
               GLfixed alignedInput;
               memcpy(&alignedInput, offsetInput + j * sizeof(GLfixed), sizeof(GLfixed));
               offsetOutput[j] = static_cast<float>(alignedInput) * divisor;
           }
       }

       // 4-component output formats would need special padding in the alpha channel.
       static_assert(!(inputComponentCount < 4 && outputComponentCount == 4),
                     "An inputComponentCount less than 4 and an outputComponentCount equal to 4 "
                     "is not supported.");

       for (size_t j = inputComponentCount; j < outputComponentCount; j++)
       {
           offsetOutput[j] = 0.0f;
       }
   }
}

template <typename T,
         size_t inputComponentCount,
         size_t outputComponentCount,
         bool normalized,
         bool toHalf>
inline void CopyToFloatVertexData(const uint8_t *input,
                                 size_t stride,
                                 size_t count,
                                 uint8_t *output)
{
   typedef std::numeric_limits<T> NL;
   typedef typename std::conditional<toHalf, GLhalf, float>::type outputType;

   for (size_t i = 0; i < count; i++)
   {
       const T *offsetInput = reinterpret_cast<const T *>(input + (stride * i));
       outputType *offsetOutput =
           reinterpret_cast<outputType *>(output) + i * outputComponentCount;

       T offsetInputAligned[inputComponentCount];
       offsetInput =
           GetAlignedOffsetInput<T, inputComponentCount>(offsetInput, &offsetInputAligned[0]);

       for (size_t j = 0; j < inputComponentCount; j++)
       {
           float result = 0;

           if (normalized)
           {
               if (NL::is_signed)
               {
                   result = static_cast<float>(offsetInput[j]) / static_cast<float>(NL::max());
                   result = result >= -1.0f ? result : -1.0f;
               }
               else
               {
                   result = static_cast<float>(offsetInput[j]) / static_cast<float>(NL::max());
               }
           }
           else
           {
               result = static_cast<float>(offsetInput[j]);
           }

           if (toHalf)
           {
               offsetOutput[j] = gl::float32ToFloat16(result);
           }
           else
           {
               offsetOutput[j] = static_cast<outputType>(result);
           }
       }

       for (size_t j = inputComponentCount; j < outputComponentCount; j++)
       {
           offsetOutput[j] = 0;
       }

       if (inputComponentCount < 4 && outputComponentCount == 4)
       {
           if (toHalf)
           {
               offsetOutput[3] = gl::Float16One;
           }
           else
           {
               offsetOutput[3] = static_cast<outputType>(gl::Float32One);
           }
       }
   }
}

template <size_t inputComponentCount, size_t outputComponentCount>
void Copy32FTo16FVertexData(const uint8_t *input, size_t stride, size_t count, uint8_t *output)
{
   const unsigned short kZero = gl::float32ToFloat16(0.0f);
   const unsigned short kOne  = gl::float32ToFloat16(1.0f);

   for (size_t i = 0; i < count; i++)
   {
       const float *offsetInput = reinterpret_cast<const float *>(input + (stride * i));
       unsigned short *offsetOutput =
           reinterpret_cast<unsigned short *>(output) + i * outputComponentCount;

       for (size_t j = 0; j < inputComponentCount; j++)
       {
           offsetOutput[j] = gl::float32ToFloat16(offsetInput[j]);
       }

       for (size_t j = inputComponentCount; j < outputComponentCount; j++)
       {
           offsetOutput[j] = (j == 3) ? kOne : kZero;
       }
   }
}

inline void CopyXYZ32FToXYZ9E5(const uint8_t *input, size_t stride, size_t count, uint8_t *output)
{
   for (size_t i = 0; i < count; i++)
   {
       const float *offsetInput   = reinterpret_cast<const float *>(input + (stride * i));
       unsigned int *offsetOutput = reinterpret_cast<unsigned int *>(output) + i;

       *offsetOutput = gl::convertRGBFloatsTo999E5(offsetInput[0], offsetInput[1], offsetInput[2]);
   }
}

inline void CopyXYZ32FToX11Y11B10F(const uint8_t *input,
                                  size_t stride,
                                  size_t count,
                                  uint8_t *output)
{
   for (size_t i = 0; i < count; i++)
   {
       const float *offsetInput   = reinterpret_cast<const float *>(input + (stride * i));
       unsigned int *offsetOutput = reinterpret_cast<unsigned int *>(output) + i;

       *offsetOutput = gl::float32ToFloat11(offsetInput[0]) << 0 |
                       gl::float32ToFloat11(offsetInput[1]) << 11 |
                       gl::float32ToFloat10(offsetInput[2]) << 22;
   }
}

namespace priv
{

template <bool isSigned, bool normalized, bool toFloat, bool toHalf>
static inline void CopyPackedRGB(uint32_t data, uint8_t *output)
{
   const uint32_t rgbSignMask  = 0x200;       // 1 set at the 9 bit
   const uint32_t negativeMask = 0xFFFFFC00;  // All bits from 10 to 31 set to 1

   if (toFloat || toHalf)
   {
       GLfloat finalValue = static_cast<GLfloat>(data);
       if (isSigned)
       {
           if (data & rgbSignMask)
           {
               int negativeNumber = data | negativeMask;
               finalValue         = static_cast<GLfloat>(negativeNumber);
           }

           if (normalized)
           {
               const int32_t maxValue = 0x1FF;       // 1 set in bits 0 through 8
               const int32_t minValue = 0xFFFFFE01;  // Inverse of maxValue

               // A 10-bit two's complement number has the possibility of being minValue - 1 but
               // OpenGL's normalization rules dictate that it should be clamped to minValue in
               // this case.
               if (finalValue < minValue)
               {
                   finalValue = minValue;
               }

               const int32_t halfRange = (maxValue - minValue) >> 1;
               finalValue              = ((finalValue - minValue) / halfRange) - 1.0f;
           }
       }
       else
       {
           if (normalized)
           {
               const uint32_t maxValue = 0x3FF;  // 1 set in bits 0 through 9
               finalValue /= static_cast<GLfloat>(maxValue);
           }
       }

       if (toHalf)
       {
           *reinterpret_cast<GLhalf *>(output) = gl::float32ToFloat16(finalValue);
       }
       else
       {
           *reinterpret_cast<GLfloat *>(output) = finalValue;
       }
   }
   else
   {
       if (isSigned)
       {
           GLshort *intOutput = reinterpret_cast<GLshort *>(output);

           if (data & rgbSignMask)
           {
               *intOutput = static_cast<GLshort>(data | negativeMask);
           }
           else
           {
               *intOutput = static_cast<GLshort>(data);
           }
       }
       else
       {
           GLushort *uintOutput = reinterpret_cast<GLushort *>(output);
           *uintOutput          = static_cast<GLushort>(data);
       }
   }
}

template <bool isSigned, bool normalized, bool toFloat, bool toHalf>
inline void CopyPackedAlpha(uint32_t data, uint8_t *output)
{
   ASSERT(data >= 0 && data <= 3);

   if (toFloat || toHalf)
   {
       GLfloat finalValue = 0;
       if (isSigned)
       {
           if (normalized)
           {
               switch (data)
               {
                   case 0x0:
                       finalValue = 0.0f;
                       break;
                   case 0x1:
                       finalValue = 1.0f;
                       break;
                   case 0x2:
                       finalValue = -1.0f;
                       break;
                   case 0x3:
                       finalValue = -1.0f;
                       break;
                   default:
                       UNREACHABLE();
               }
           }
           else
           {
               switch (data)
               {
                   case 0x0:
                       finalValue = 0.0f;
                       break;
                   case 0x1:
                       finalValue = 1.0f;
                       break;
                   case 0x2:
                       finalValue = -2.0f;
                       break;
                   case 0x3:
                       finalValue = -1.0f;
                       break;
                   default:
                       UNREACHABLE();
               }
           }
       }
       else
       {
           if (normalized)
           {
               finalValue = data / 3.0f;
           }
           else
           {
               finalValue = static_cast<float>(data);
           }
       }

       if (toHalf)
       {
           *reinterpret_cast<GLhalf *>(output) = gl::float32ToFloat16(finalValue);
       }
       else
       {
           *reinterpret_cast<GLfloat *>(output) = finalValue;
       }
   }
   else
   {
       if (isSigned)
       {
           GLshort *intOutput = reinterpret_cast<GLshort *>(output);
           switch (data)
           {
               case 0x0:
                   *intOutput = 0;
                   break;
               case 0x1:
                   *intOutput = 1;
                   break;
               case 0x2:
                   *intOutput = -2;
                   break;
               case 0x3:
                   *intOutput = -1;
                   break;
               default:
                   UNREACHABLE();
           }
       }
       else
       {
           *reinterpret_cast<GLushort *>(output) = static_cast<GLushort>(data);
       }
   }
}

}  // namespace priv

template <bool isSigned, bool normalized, bool toFloat, bool toHalf>
inline void CopyXYZ10W2ToXYZWFloatVertexData(const uint8_t *input,
                                            size_t stride,
                                            size_t count,
                                            uint8_t *output)
{
   const size_t outputComponentSize = toFloat && !toHalf ? 4 : 2;
   const size_t componentCount      = 4;

   const uint32_t rgbMask  = 0x3FF;  // 1 set in bits 0 through 9
   const size_t redShift   = 0;      // red is bits 0 through 9
   const size_t greenShift = 10;     // green is bits 10 through 19
   const size_t blueShift  = 20;     // blue is bits 20 through 29

   const uint32_t alphaMask = 0x3;  // 1 set in bits 0 and 1
   const size_t alphaShift  = 30;   // Alpha is the 30 and 31 bits

   for (size_t i = 0; i < count; i++)
   {
       GLuint packedValue    = *reinterpret_cast<const GLuint *>(input + (i * stride));
       uint8_t *offsetOutput = output + (i * outputComponentSize * componentCount);

       priv::CopyPackedRGB<isSigned, normalized, toFloat, toHalf>(
           (packedValue >> redShift) & rgbMask, offsetOutput + (0 * outputComponentSize));
       priv::CopyPackedRGB<isSigned, normalized, toFloat, toHalf>(
           (packedValue >> greenShift) & rgbMask, offsetOutput + (1 * outputComponentSize));
       priv::CopyPackedRGB<isSigned, normalized, toFloat, toHalf>(
           (packedValue >> blueShift) & rgbMask, offsetOutput + (2 * outputComponentSize));
       priv::CopyPackedAlpha<isSigned, normalized, toFloat, toHalf>(
           (packedValue >> alphaShift) & alphaMask, offsetOutput + (3 * outputComponentSize));
   }
}

template <bool isSigned, bool normalized, bool toHalf>
inline void CopyXYZ10ToXYZWFloatVertexData(const uint8_t *input,
                                          size_t stride,
                                          size_t count,
                                          uint8_t *output)
{
   const size_t outputComponentSize = toHalf ? 2 : 4;
   const size_t componentCount      = 4;

   const uint32_t rgbMask  = 0x3FF;  // 1 set in bits 0 through 9
   const size_t redShift   = 22;     // red is bits 22 through 31
   const size_t greenShift = 12;     // green is bits 12 through 21
   const size_t blueShift  = 2;      // blue is bits 2 through 11

   const uint32_t alphaDefaultValueBits = normalized ? (isSigned ? 0x1 : 0x3) : 0x1;

   for (size_t i = 0; i < count; i++)
   {
       GLuint packedValue    = *reinterpret_cast<const GLuint *>(input + (i * stride));
       uint8_t *offsetOutput = output + (i * outputComponentSize * componentCount);

       priv::CopyPackedRGB<isSigned, normalized, true, toHalf>(
           (packedValue >> redShift) & rgbMask, offsetOutput + (0 * outputComponentSize));
       priv::CopyPackedRGB<isSigned, normalized, true, toHalf>(
           (packedValue >> greenShift) & rgbMask, offsetOutput + (1 * outputComponentSize));
       priv::CopyPackedRGB<isSigned, normalized, true, toHalf>(
           (packedValue >> blueShift) & rgbMask, offsetOutput + (2 * outputComponentSize));
       priv::CopyPackedAlpha<isSigned, normalized, true, toHalf>(
           alphaDefaultValueBits, offsetOutput + (3 * outputComponentSize));
   }
}

template <bool isSigned, bool normalized, bool toHalf>
inline void CopyW2XYZ10ToXYZWFloatVertexData(const uint8_t *input,
                                            size_t stride,
                                            size_t count,
                                            uint8_t *output)
{
   const size_t outputComponentSize = toHalf ? 2 : 4;
   const size_t componentCount      = 4;

   const uint32_t rgbMask  = 0x3FF;  // 1 set in bits 0 through 9
   const size_t redShift   = 22;     // red is bits 22 through 31
   const size_t greenShift = 12;     // green is bits 12 through 21
   const size_t blueShift  = 2;      // blue is bits 2 through 11

   const uint32_t alphaMask = 0x3;  // 1 set in bits 0 and 1
   const size_t alphaShift  = 0;    // Alpha is the 30 and 31 bits

   for (size_t i = 0; i < count; i++)
   {
       GLuint packedValue    = *reinterpret_cast<const GLuint *>(input + (i * stride));
       uint8_t *offsetOutput = output + (i * outputComponentSize * componentCount);

       priv::CopyPackedRGB<isSigned, normalized, true, toHalf>(
           (packedValue >> redShift) & rgbMask, offsetOutput + (0 * outputComponentSize));
       priv::CopyPackedRGB<isSigned, normalized, true, toHalf>(
           (packedValue >> greenShift) & rgbMask, offsetOutput + (1 * outputComponentSize));
       priv::CopyPackedRGB<isSigned, normalized, true, toHalf>(
           (packedValue >> blueShift) & rgbMask, offsetOutput + (2 * outputComponentSize));
       priv::CopyPackedAlpha<isSigned, normalized, true, toHalf>(
           (packedValue >> alphaShift) & alphaMask, offsetOutput + (3 * outputComponentSize));
   }
}
}  // namespace rx