internal static void FromVector4 <TPixel>(
Configuration configuration,
PixelOperations <TPixel> pixelOperations,
ReadOnlySpan <Vector4> sourceVectors,
Span <TPixel> destPixels,
bool scaled)
where TPixel : struct, IPixel <TPixel>
{
Guard.NotNull(configuration, nameof(configuration));
Guard.DestinationShouldNotBeTooShort(sourceVectors, destPixels, nameof(destPixels));
int count = sourceVectors.Length;
// Not worth for small buffers:
if (count < Vector4ConversionThreshold)
{
FromVector4Fallback(sourceVectors, destPixels, scaled);
return;
}
// For the opposite direction it's not easy to implement the trick used in RunRgba32CompatibleToVector4Conversion,
// so let's allocate a temporary buffer as usually:
using (IMemoryOwner <Rgba32> tempBuffer = configuration.MemoryAllocator.Allocate <Rgba32>(count))
{
Span <Rgba32> tempSpan = tempBuffer.Memory.Span;
SimdUtils.BulkConvertNormalizedFloatToByteClampOverflows(
MemoryMarshal.Cast <Vector4, float>(sourceVectors),
MemoryMarshal.Cast <Rgba32, byte>(tempSpan));
pixelOperations.FromRgba32(configuration, tempSpan, destPixels);
}
}
/// <inheritdoc />
internal override void PackFromVector4(ReadOnlySpan <Vector4> sourceVectors, Span <Rgba32> destinationColors, int count)
{
GuardSpans(sourceVectors, nameof(sourceVectors), destinationColors, nameof(destinationColors), count);
sourceVectors = sourceVectors.Slice(0, count);
destinationColors = destinationColors.Slice(0, count);
SimdUtils.BulkConvertNormalizedFloatToByteClampOverflows(
MemoryMarshal.Cast <Vector4, float>(sourceVectors),
MemoryMarshal.Cast <Rgba32, byte>(destinationColors));
}
/// <inheritdoc />
internal override void FromVector4(
Configuration configuration,
ReadOnlySpan <Vector4> sourceVectors,
Span <Rgba32> destPixels)
{
Guard.DestinationShouldNotBeTooShort(sourceVectors, destPixels, nameof(destPixels));
destPixels = destPixels.Slice(0, sourceVectors.Length);
SimdUtils.BulkConvertNormalizedFloatToByteClampOverflows(
MemoryMarshal.Cast <Vector4, float>(sourceVectors),
MemoryMarshal.Cast <Rgba32, byte>(destPixels));
}
/// <inheritdoc />
internal override void FromVector4Destructive(
Configuration configuration,
Span <Vector4> sourceVectors,
Span <Rgba32> destPixels,
PixelConversionModifiers modifiers)
{
Guard.DestinationShouldNotBeTooShort(sourceVectors, destPixels, nameof(destPixels));
destPixels = destPixels.Slice(0, sourceVectors.Length);
Vector4Converters.ApplyBackwardConversionModifiers(sourceVectors, modifiers);
SimdUtils.BulkConvertNormalizedFloatToByteClampOverflows(
MemoryMarshal.Cast <Vector4, float>(sourceVectors),
MemoryMarshal.Cast <Rgba32, byte>(destPixels));
}
public void BulkConvertNormalizedFloatToByteClampOverflows(int count)
{
TestImpl_BulkConvertNormalizedFloatToByteClampOverflows(count, (s, d) => SimdUtils.BulkConvertNormalizedFloatToByteClampOverflows(s.Span, d.Span));
// For small values, let's stress test the implementation a bit:
if (count > 0 && count < 10)
{
for (int i = 0; i < 20; i++)
{
TestImpl_BulkConvertNormalizedFloatToByteClampOverflows(
count,
(s, d) => SimdUtils.BulkConvertNormalizedFloatToByteClampOverflows(s.Span, d.Span),
i + 42);
}
}
}
public void BulkConvertNormalizedFloatToByteClampOverflows(int seed, int count)
{
if (this.SkipOnNonAvx2())
{
return;
}
float[] orig = new Random(seed).GenerateRandomRoundedFloatArray(count, -50, 444);
float[] normalized = orig.Select(f => f / 255f).ToArray();
byte[] dest = new byte[count];
SimdUtils.BulkConvertNormalizedFloatToByteClampOverflows(normalized, dest);
byte[] expected = orig.Select(f => (byte)Clamp255(f)).ToArray();
Assert.Equal(expected, dest);
}
internal static void FromVector4 <TPixel>(
Configuration configuration,
PixelOperations <TPixel> pixelOperations,
Span <Vector4> sourceVectors,
Span <TPixel> destPixels,
PixelConversionModifiers modifiers)
where TPixel : unmanaged, IPixel <TPixel>
{
Guard.NotNull(configuration, nameof(configuration));
Guard.DestinationShouldNotBeTooShort(sourceVectors, destPixels, nameof(destPixels));
int count = sourceVectors.Length;
// Not worth for small buffers:
if (count < Vector4ConversionThreshold)
{
Default.UnsafeFromVector4(sourceVectors, destPixels, modifiers);
return;
}
// TODO: Investigate optimized 1-pass approach!
ApplyBackwardConversionModifiers(sourceVectors, modifiers);
// For the opposite direction it's not easy to implement the trick used in RunRgba32CompatibleToVector4Conversion,
// so let's allocate a temporary buffer as usually:
using (IMemoryOwner <Rgba32> tempBuffer = configuration.MemoryAllocator.Allocate <Rgba32>(count))
{
Span <Rgba32> tempSpan = tempBuffer.Memory.Span;
SimdUtils.BulkConvertNormalizedFloatToByteClampOverflows(
MemoryMarshal.Cast <Vector4, float>(sourceVectors),
MemoryMarshal.Cast <Rgba32, byte>(tempSpan));
pixelOperations.FromRgba32(configuration, tempSpan, destPixels);
}
}