mirror of
https://github.com/Ryujinx/Ryujinx.git
synced 2024-12-24 10:56:03 +00:00
1006 lines
38 KiB
C#
1006 lines
38 KiB
C#
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using Ryujinx.Graphics.Texture.Utils;
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using System;
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using System.Diagnostics;
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using System.Numerics;
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using System.Runtime.CompilerServices;
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using System.Runtime.InteropServices;
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using System.Runtime.Intrinsics;
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using System.Runtime.Intrinsics.X86;
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using System.Threading.Tasks;
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namespace Ryujinx.Graphics.Texture.Encoders
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{
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static class BC7Encoder
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{
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private const int MinColorVarianceForModeChange = 160;
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public static void Encode(Memory<byte> outputStorage, ReadOnlyMemory<byte> data, int width, int height, EncodeMode mode)
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{
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int widthInBlocks = (width + 3) / 4;
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int heightInBlocks = (height + 3) / 4;
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bool fastMode = (mode & EncodeMode.ModeMask) == EncodeMode.Fast;
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if (mode.HasFlag(EncodeMode.Multithreaded))
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{
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Parallel.For(0, heightInBlocks, (yInBlocks) =>
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{
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Span<ulong> output = MemoryMarshal.Cast<byte, ulong>(outputStorage.Span);
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int y = yInBlocks * 4;
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for (int xInBlocks = 0; xInBlocks < widthInBlocks; xInBlocks++)
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{
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int x = xInBlocks * 4;
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Block block = CompressBlock(data.Span, x, y, width, height, fastMode);
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int offset = (yInBlocks * widthInBlocks + xInBlocks) * 2;
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output[offset] = block.Low;
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output[offset + 1] = block.High;
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}
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});
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}
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else
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{
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Span<ulong> output = MemoryMarshal.Cast<byte, ulong>(outputStorage.Span);
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int offset = 0;
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for (int y = 0; y < height; y += 4)
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{
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for (int x = 0; x < width; x += 4)
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{
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Block block = CompressBlock(data.Span, x, y, width, height, fastMode);
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output[offset++] = block.Low;
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output[offset++] = block.High;
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}
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}
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}
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}
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private static readonly int[] _mostFrequentPartitions = new int[]
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{
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0, 13, 2, 1, 15, 14, 10, 23
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};
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private static Block CompressBlock(ReadOnlySpan<byte> data, int x, int y, int width, int height, bool fastMode)
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{
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int w = Math.Min(4, width - x);
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int h = Math.Min(4, height - y);
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var dataUint = MemoryMarshal.Cast<byte, uint>(data);
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int baseOffset = y * width + x;
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Span<uint> tile = stackalloc uint[w * h];
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for (int ty = 0; ty < h; ty++)
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{
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int rowOffset = baseOffset + ty * width;
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for (int tx = 0; tx < w; tx++)
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{
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tile[ty * w + tx] = dataUint[rowOffset + tx];
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}
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}
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return fastMode ? EncodeFast(tile, w, h) : EncodeExhaustive(tile, w, h);
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}
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private static Block EncodeFast(ReadOnlySpan<uint> tile, int w, int h)
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{
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(RgbaColor8 minColor, RgbaColor8 maxColor) = BC67Utils.GetMinMaxColors(tile, w, h);
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bool alphaNotOne = minColor.A != 255 || maxColor.A != 255;
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int variance = BC67Utils.SquaredDifference(minColor.GetColor32(), maxColor.GetColor32());
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int selectedMode;
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int indexMode = 0;
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if (alphaNotOne)
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{
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bool constantAlpha = minColor.A == maxColor.A;
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if (constantAlpha)
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{
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selectedMode = variance > MinColorVarianceForModeChange ? 7 : 6;
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}
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else
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{
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if (variance > MinColorVarianceForModeChange)
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{
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Span<uint> uniqueRGB = stackalloc uint[16];
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Span<uint> uniqueAlpha = stackalloc uint[16];
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int uniqueRGBCount = 0;
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int uniqueAlphaCount = 0;
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uint rgbMask = new RgbaColor8(255, 255, 255, 0).ToUInt32();
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uint alphaMask = new RgbaColor8(0, 0, 0, 255).ToUInt32();
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for (int i = 0; i < tile.Length; i++)
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{
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uint c = tile[i];
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if (!uniqueRGB.Slice(0, uniqueRGBCount).Contains(c & rgbMask))
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{
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uniqueRGB[uniqueRGBCount++] = c & rgbMask;
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}
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if (!uniqueAlpha.Slice(0, uniqueAlphaCount).Contains(c & alphaMask))
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{
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uniqueAlpha[uniqueAlphaCount++] = c & alphaMask;
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}
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}
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selectedMode = 4;
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indexMode = uniqueRGBCount > uniqueAlphaCount ? 1 : 0;
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}
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else
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{
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selectedMode = 5;
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}
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}
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}
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else
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{
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if (variance > MinColorVarianceForModeChange)
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{
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selectedMode = 1;
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}
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else
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{
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selectedMode = 6;
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}
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}
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int selectedPartition = 0;
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if (selectedMode == 1 || selectedMode == 7)
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{
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int partitionSelectionLowestError = int.MaxValue;
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for (int i = 0; i < _mostFrequentPartitions.Length; i++)
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{
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int p = _mostFrequentPartitions[i];
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int error = GetEndPointSelectionErrorFast(tile, 2, p, w, h, partitionSelectionLowestError);
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if (error < partitionSelectionLowestError)
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{
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partitionSelectionLowestError = error;
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selectedPartition = p;
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}
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}
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}
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return Encode(selectedMode, selectedPartition, 0, indexMode, fastMode: true, tile, w, h, out _);
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}
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private static Block EncodeExhaustive(ReadOnlySpan<uint> tile, int w, int h)
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{
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Block bestBlock = default;
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int lowestError = int.MaxValue;
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int lowestErrorSubsets = int.MaxValue;
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for (int m = 0; m < 8; m++)
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{
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for (int r = 0; r < (m == 4 || m == 5 ? 4 : 1); r++)
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{
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for (int im = 0; im < (m == 4 ? 2 : 1); im++)
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{
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for (int p = 0; p < 1 << BC67Tables.BC7ModeInfos[m].PartitionBitCount; p++)
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{
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Block block = Encode(m, p, r, im, fastMode: false, tile, w, h, out int maxError);
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if (maxError < lowestError || (maxError == lowestError && BC67Tables.BC7ModeInfos[m].SubsetCount < lowestErrorSubsets))
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{
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lowestError = maxError;
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lowestErrorSubsets = BC67Tables.BC7ModeInfos[m].SubsetCount;
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bestBlock = block;
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}
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}
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}
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}
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}
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return bestBlock;
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}
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private static Block Encode(
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int mode,
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int partition,
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int rotation,
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int indexMode,
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bool fastMode,
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ReadOnlySpan<uint> tile,
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int w,
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int h,
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out int errorSum)
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{
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BC7ModeInfo modeInfo = BC67Tables.BC7ModeInfos[mode];
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int subsetCount = modeInfo.SubsetCount;
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int partitionBitCount = modeInfo.PartitionBitCount;
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int rotationBitCount = modeInfo.RotationBitCount;
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int indexModeBitCount = modeInfo.IndexModeBitCount;
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int colorDepth = modeInfo.ColorDepth;
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int alphaDepth = modeInfo.AlphaDepth;
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int pBits = modeInfo.PBits;
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int colorIndexBitCount = modeInfo.ColorIndexBitCount;
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int alphaIndexBitCount = modeInfo.AlphaIndexBitCount;
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bool separateAlphaIndices = alphaIndexBitCount != 0;
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uint alphaMask;
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if (separateAlphaIndices)
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{
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alphaMask = rotation switch
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{
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1 => new RgbaColor8(255, 0, 0, 0).ToUInt32(),
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2 => new RgbaColor8(0, 255, 0, 0).ToUInt32(),
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3 => new RgbaColor8(0, 0, 255, 0).ToUInt32(),
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_ => new RgbaColor8(0, 0, 0, 255).ToUInt32()
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};
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}
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else
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{
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alphaMask = new RgbaColor8(0, 0, 0, 0).ToUInt32();
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}
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if (indexMode != 0)
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{
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alphaMask = ~alphaMask;
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}
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//
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// Select color palette.
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//
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Span<uint> endPoints0 = stackalloc uint[subsetCount];
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Span<uint> endPoints1 = stackalloc uint[subsetCount];
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SelectEndPoints(
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tile,
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w,
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h,
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endPoints0,
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endPoints1,
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subsetCount,
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partition,
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colorIndexBitCount,
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colorDepth,
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alphaDepth,
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~alphaMask,
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fastMode);
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if (separateAlphaIndices)
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{
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SelectEndPoints(
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tile,
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w,
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h,
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endPoints0,
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endPoints1,
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subsetCount,
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partition,
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alphaIndexBitCount,
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colorDepth,
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alphaDepth,
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alphaMask,
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fastMode);
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}
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Span<int> pBitValues = stackalloc int[pBits];
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for (int i = 0; i < pBits; i++)
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{
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int pBit;
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if (pBits == subsetCount)
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{
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pBit = GetPBit(endPoints0[i], endPoints1[i], colorDepth, alphaDepth);
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}
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else
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{
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int subset = i >> 1;
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uint color = (i & 1) == 0 ? endPoints0[subset] : endPoints1[subset];
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pBit = GetPBit(color, colorDepth, alphaDepth);
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}
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pBitValues[i] = pBit;
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}
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int colorIndexCount = 1 << colorIndexBitCount;
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int alphaIndexCount = 1 << alphaIndexBitCount;
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Span<byte> colorIndices = stackalloc byte[16];
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Span<byte> alphaIndices = stackalloc byte[16];
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errorSum = BC67Utils.SelectIndices(
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tile,
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w,
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h,
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endPoints0,
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endPoints1,
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pBitValues,
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colorIndices,
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subsetCount,
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partition,
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colorIndexBitCount,
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colorIndexCount,
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colorDepth,
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alphaDepth,
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pBits,
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alphaMask);
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if (separateAlphaIndices)
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{
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errorSum += BC67Utils.SelectIndices(
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tile,
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w,
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h,
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endPoints0,
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endPoints1,
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pBitValues,
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alphaIndices,
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subsetCount,
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partition,
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alphaIndexBitCount,
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alphaIndexCount,
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colorDepth,
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alphaDepth,
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pBits,
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~alphaMask);
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}
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Span<bool> colorSwapSubset = stackalloc bool[3];
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for (int i = 0; i < 3; i++)
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{
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colorSwapSubset[i] = colorIndices[BC67Tables.FixUpIndices[subsetCount - 1][partition][i]] >= (colorIndexCount >> 1);
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}
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bool alphaSwapSubset = alphaIndices[0] >= (alphaIndexCount >> 1);
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Block block = new Block();
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int offset = 0;
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block.Encode(1UL << mode, ref offset, mode + 1);
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block.Encode((ulong)partition, ref offset, partitionBitCount);
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block.Encode((ulong)rotation, ref offset, rotationBitCount);
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block.Encode((ulong)indexMode, ref offset, indexModeBitCount);
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for (int comp = 0; comp < 3; comp++)
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{
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int rotatedComp = comp;
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if (((comp + 1) & 3) == rotation)
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{
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rotatedComp = 3;
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}
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for (int subset = 0; subset < subsetCount; subset++)
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{
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RgbaColor8 color0 = RgbaColor8.FromUInt32(endPoints0[subset]);
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RgbaColor8 color1 = RgbaColor8.FromUInt32(endPoints1[subset]);
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int pBit0 = -1, pBit1 = -1;
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if (pBits == subsetCount)
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{
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pBit0 = pBit1 = pBitValues[subset];
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}
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else if (pBits != 0)
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{
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pBit0 = pBitValues[subset * 2];
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pBit1 = pBitValues[subset * 2 + 1];
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}
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if (indexMode == 0 ? colorSwapSubset[subset] : alphaSwapSubset)
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{
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block.Encode(BC67Utils.QuantizeComponent(color1.GetComponent(rotatedComp), colorDepth, pBit1), ref offset, colorDepth);
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block.Encode(BC67Utils.QuantizeComponent(color0.GetComponent(rotatedComp), colorDepth, pBit0), ref offset, colorDepth);
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}
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else
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{
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block.Encode(BC67Utils.QuantizeComponent(color0.GetComponent(rotatedComp), colorDepth, pBit0), ref offset, colorDepth);
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block.Encode(BC67Utils.QuantizeComponent(color1.GetComponent(rotatedComp), colorDepth, pBit1), ref offset, colorDepth);
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}
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}
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}
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if (alphaDepth != 0)
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{
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int rotatedComp = (rotation - 1) & 3;
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for (int subset = 0; subset < subsetCount; subset++)
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{
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RgbaColor8 color0 = RgbaColor8.FromUInt32(endPoints0[subset]);
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RgbaColor8 color1 = RgbaColor8.FromUInt32(endPoints1[subset]);
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int pBit0 = -1, pBit1 = -1;
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if (pBits == subsetCount)
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{
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pBit0 = pBit1 = pBitValues[subset];
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}
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else if (pBits != 0)
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{
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pBit0 = pBitValues[subset * 2];
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pBit1 = pBitValues[subset * 2 + 1];
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}
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if (separateAlphaIndices && indexMode == 0 ? alphaSwapSubset : colorSwapSubset[subset])
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{
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block.Encode(BC67Utils.QuantizeComponent(color1.GetComponent(rotatedComp), alphaDepth, pBit1), ref offset, alphaDepth);
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block.Encode(BC67Utils.QuantizeComponent(color0.GetComponent(rotatedComp), alphaDepth, pBit0), ref offset, alphaDepth);
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}
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else
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{
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|||
|
block.Encode(BC67Utils.QuantizeComponent(color0.GetComponent(rotatedComp), alphaDepth, pBit0), ref offset, alphaDepth);
|
|||
|
block.Encode(BC67Utils.QuantizeComponent(color1.GetComponent(rotatedComp), alphaDepth, pBit1), ref offset, alphaDepth);
|
|||
|
}
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
for (int i = 0; i < pBits; i++)
|
|||
|
{
|
|||
|
block.Encode((ulong)pBitValues[i], ref offset, 1);
|
|||
|
}
|
|||
|
|
|||
|
byte[] fixUpTable = BC67Tables.FixUpIndices[subsetCount - 1][partition];
|
|||
|
|
|||
|
for (int i = 0; i < 16; i++)
|
|||
|
{
|
|||
|
int subset = BC67Tables.PartitionTable[subsetCount - 1][partition][i];
|
|||
|
byte index = colorIndices[i];
|
|||
|
|
|||
|
if (colorSwapSubset[subset])
|
|||
|
{
|
|||
|
index = (byte)(index ^ (colorIndexCount - 1));
|
|||
|
}
|
|||
|
|
|||
|
int finalIndexBitCount = i == fixUpTable[subset] ? colorIndexBitCount - 1 : colorIndexBitCount;
|
|||
|
|
|||
|
Debug.Assert(index < (1 << finalIndexBitCount));
|
|||
|
|
|||
|
block.Encode(index, ref offset, finalIndexBitCount);
|
|||
|
}
|
|||
|
|
|||
|
if (separateAlphaIndices)
|
|||
|
{
|
|||
|
for (int i = 0; i < 16; i++)
|
|||
|
{
|
|||
|
byte index = alphaIndices[i];
|
|||
|
|
|||
|
if (alphaSwapSubset)
|
|||
|
{
|
|||
|
index = (byte)(index ^ (alphaIndexCount - 1));
|
|||
|
}
|
|||
|
|
|||
|
int finalIndexBitCount = i == 0 ? alphaIndexBitCount - 1 : alphaIndexBitCount;
|
|||
|
|
|||
|
Debug.Assert(index < (1 << finalIndexBitCount));
|
|||
|
|
|||
|
block.Encode(index, ref offset, finalIndexBitCount);
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
return block;
|
|||
|
}
|
|||
|
|
|||
|
private static unsafe int GetEndPointSelectionErrorFast(ReadOnlySpan<uint> tile, int subsetCount, int partition, int w, int h, int maxError)
|
|||
|
{
|
|||
|
byte[] partitionTable = BC67Tables.PartitionTable[subsetCount - 1][partition];
|
|||
|
|
|||
|
Span<RgbaColor8> minColors = stackalloc RgbaColor8[subsetCount];
|
|||
|
Span<RgbaColor8> maxColors = stackalloc RgbaColor8[subsetCount];
|
|||
|
|
|||
|
BC67Utils.GetMinMaxColors(partitionTable, tile, w, h, minColors, maxColors, subsetCount);
|
|||
|
|
|||
|
Span<uint> endPoints0 = stackalloc uint[subsetCount];
|
|||
|
Span<uint> endPoints1 = stackalloc uint[subsetCount];
|
|||
|
|
|||
|
SelectEndPointsFast(partitionTable, tile, w, h, subsetCount, minColors, maxColors, endPoints0, endPoints1, uint.MaxValue);
|
|||
|
|
|||
|
Span<RgbaColor32> palette = stackalloc RgbaColor32[8];
|
|||
|
|
|||
|
int errorSum = 0;
|
|||
|
|
|||
|
for (int subset = 0; subset < subsetCount; subset++)
|
|||
|
{
|
|||
|
RgbaColor32 blockDir = maxColors[subset].GetColor32() - minColors[subset].GetColor32();
|
|||
|
int sum = blockDir.R + blockDir.G + blockDir.B + blockDir.A;
|
|||
|
if (sum != 0)
|
|||
|
{
|
|||
|
blockDir = (blockDir << 6) / new RgbaColor32(sum);
|
|||
|
}
|
|||
|
|
|||
|
uint c0 = endPoints0[subset];
|
|||
|
uint c1 = endPoints1[subset];
|
|||
|
|
|||
|
int pBit0 = GetPBit(c0, 6, 0);
|
|||
|
int pBit1 = GetPBit(c1, 6, 0);
|
|||
|
|
|||
|
c0 = BC67Utils.Quantize(RgbaColor8.FromUInt32(c0), 6, 0, pBit0).ToUInt32();
|
|||
|
c1 = BC67Utils.Quantize(RgbaColor8.FromUInt32(c1), 6, 0, pBit1).ToUInt32();
|
|||
|
|
|||
|
if (Sse41.IsSupported)
|
|||
|
{
|
|||
|
Vector128<byte> c0Rep = Vector128.Create(c0).AsByte();
|
|||
|
Vector128<byte> c1Rep = Vector128.Create(c1).AsByte();
|
|||
|
|
|||
|
Vector128<byte> c0c1 = Sse2.UnpackLow(c0Rep, c1Rep);
|
|||
|
|
|||
|
Vector128<byte> rWeights;
|
|||
|
Vector128<byte> lWeights;
|
|||
|
|
|||
|
fixed (byte* pWeights = BC67Tables.Weights[1], pInvWeights = BC67Tables.InverseWeights[1])
|
|||
|
{
|
|||
|
rWeights = Sse2.LoadScalarVector128((ulong*)pWeights).AsByte();
|
|||
|
lWeights = Sse2.LoadScalarVector128((ulong*)pInvWeights).AsByte();
|
|||
|
}
|
|||
|
|
|||
|
Vector128<byte> iWeights = Sse2.UnpackLow(rWeights, lWeights);
|
|||
|
Vector128<byte> iWeights01 = Sse2.UnpackLow(iWeights.AsInt16(), iWeights.AsInt16()).AsByte();
|
|||
|
Vector128<byte> iWeights23 = Sse2.UnpackHigh(iWeights.AsInt16(), iWeights.AsInt16()).AsByte();
|
|||
|
Vector128<byte> iWeights0 = Sse2.UnpackLow(iWeights01.AsInt16(), iWeights01.AsInt16()).AsByte();
|
|||
|
Vector128<byte> iWeights1 = Sse2.UnpackHigh(iWeights01.AsInt16(), iWeights01.AsInt16()).AsByte();
|
|||
|
Vector128<byte> iWeights2 = Sse2.UnpackLow(iWeights23.AsInt16(), iWeights23.AsInt16()).AsByte();
|
|||
|
Vector128<byte> iWeights3 = Sse2.UnpackHigh(iWeights23.AsInt16(), iWeights23.AsInt16()).AsByte();
|
|||
|
|
|||
|
static Vector128<short> ShiftRoundToNearest(Vector128<short> x)
|
|||
|
{
|
|||
|
return Sse2.ShiftRightLogical(Sse2.Add(x, Vector128.Create((short)32)), 6);
|
|||
|
}
|
|||
|
|
|||
|
Vector128<short> pal0 = ShiftRoundToNearest(Ssse3.MultiplyAddAdjacent(c0c1, iWeights0.AsSByte()));
|
|||
|
Vector128<short> pal1 = ShiftRoundToNearest(Ssse3.MultiplyAddAdjacent(c0c1, iWeights1.AsSByte()));
|
|||
|
Vector128<short> pal2 = ShiftRoundToNearest(Ssse3.MultiplyAddAdjacent(c0c1, iWeights2.AsSByte()));
|
|||
|
Vector128<short> pal3 = ShiftRoundToNearest(Ssse3.MultiplyAddAdjacent(c0c1, iWeights3.AsSByte()));
|
|||
|
|
|||
|
for (int i = 0; i < tile.Length; i++)
|
|||
|
{
|
|||
|
if (partitionTable[i] != subset)
|
|||
|
{
|
|||
|
continue;
|
|||
|
}
|
|||
|
|
|||
|
uint c = tile[i];
|
|||
|
|
|||
|
Vector128<short> color = Sse41.ConvertToVector128Int16(Vector128.Create(c).AsByte());
|
|||
|
|
|||
|
Vector128<short> delta0 = Sse2.Subtract(color, pal0);
|
|||
|
Vector128<short> delta1 = Sse2.Subtract(color, pal1);
|
|||
|
Vector128<short> delta2 = Sse2.Subtract(color, pal2);
|
|||
|
Vector128<short> delta3 = Sse2.Subtract(color, pal3);
|
|||
|
|
|||
|
Vector128<int> deltaSum0 = Sse2.MultiplyAddAdjacent(delta0, delta0);
|
|||
|
Vector128<int> deltaSum1 = Sse2.MultiplyAddAdjacent(delta1, delta1);
|
|||
|
Vector128<int> deltaSum2 = Sse2.MultiplyAddAdjacent(delta2, delta2);
|
|||
|
Vector128<int> deltaSum3 = Sse2.MultiplyAddAdjacent(delta3, delta3);
|
|||
|
|
|||
|
Vector128<int> deltaSum01 = Ssse3.HorizontalAdd(deltaSum0, deltaSum1);
|
|||
|
Vector128<int> deltaSum23 = Ssse3.HorizontalAdd(deltaSum2, deltaSum3);
|
|||
|
|
|||
|
Vector128<ushort> delta = Sse41.PackUnsignedSaturate(deltaSum01, deltaSum23);
|
|||
|
|
|||
|
Vector128<ushort> min = Sse41.MinHorizontal(delta);
|
|||
|
|
|||
|
errorSum += min.GetElement(0);
|
|||
|
}
|
|||
|
}
|
|||
|
else
|
|||
|
{
|
|||
|
RgbaColor32 e032 = RgbaColor8.FromUInt32(c0).GetColor32();
|
|||
|
RgbaColor32 e132 = RgbaColor8.FromUInt32(c1).GetColor32();
|
|||
|
|
|||
|
palette[0] = e032;
|
|||
|
palette[palette.Length - 1] = e132;
|
|||
|
|
|||
|
for (int i = 1; i < palette.Length - 1; i++)
|
|||
|
{
|
|||
|
palette[i] = BC67Utils.Interpolate(e032, e132, i, 3);
|
|||
|
}
|
|||
|
|
|||
|
for (int i = 0; i < tile.Length; i++)
|
|||
|
{
|
|||
|
if (partitionTable[i] != subset)
|
|||
|
{
|
|||
|
continue;
|
|||
|
}
|
|||
|
|
|||
|
uint c = tile[i];
|
|||
|
RgbaColor32 color = Unsafe.As<uint, RgbaColor8>(ref c).GetColor32();
|
|||
|
|
|||
|
int bestMatchScore = int.MaxValue;
|
|||
|
|
|||
|
for (int j = 0; j < palette.Length; j++)
|
|||
|
{
|
|||
|
int score = BC67Utils.SquaredDifference(color, palette[j]);
|
|||
|
|
|||
|
if (score < bestMatchScore)
|
|||
|
{
|
|||
|
bestMatchScore = score;
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
errorSum += bestMatchScore;
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
// No point in continuing if we are already above maximum.
|
|||
|
if (errorSum >= maxError)
|
|||
|
{
|
|||
|
return int.MaxValue;
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
return errorSum;
|
|||
|
}
|
|||
|
|
|||
|
private static void SelectEndPoints(
|
|||
|
ReadOnlySpan<uint> tile,
|
|||
|
int w,
|
|||
|
int h,
|
|||
|
Span<uint> endPoints0,
|
|||
|
Span<uint> endPoints1,
|
|||
|
int subsetCount,
|
|||
|
int partition,
|
|||
|
int indexBitCount,
|
|||
|
int colorDepth,
|
|||
|
int alphaDepth,
|
|||
|
uint writeMask,
|
|||
|
bool fastMode)
|
|||
|
{
|
|||
|
byte[] partitionTable = BC67Tables.PartitionTable[subsetCount - 1][partition];
|
|||
|
|
|||
|
Span<RgbaColor8> minColors = stackalloc RgbaColor8[subsetCount];
|
|||
|
Span<RgbaColor8> maxColors = stackalloc RgbaColor8[subsetCount];
|
|||
|
|
|||
|
BC67Utils.GetMinMaxColors(partitionTable, tile, w, h, minColors, maxColors, subsetCount);
|
|||
|
|
|||
|
uint inverseMask = ~writeMask;
|
|||
|
|
|||
|
for (int i = 0; i < subsetCount; i++)
|
|||
|
{
|
|||
|
Unsafe.As<RgbaColor8, uint>(ref minColors[i]) |= inverseMask;
|
|||
|
Unsafe.As<RgbaColor8, uint>(ref maxColors[i]) |= inverseMask;
|
|||
|
}
|
|||
|
|
|||
|
if (fastMode)
|
|||
|
{
|
|||
|
SelectEndPointsFast(partitionTable, tile, w, h, subsetCount, minColors, maxColors, endPoints0, endPoints1, writeMask);
|
|||
|
}
|
|||
|
else
|
|||
|
{
|
|||
|
Span<RgbaColor8> colors = stackalloc RgbaColor8[subsetCount * 16];
|
|||
|
Span<byte> counts = stackalloc byte[subsetCount];
|
|||
|
|
|||
|
int i = 0;
|
|||
|
for (int ty = 0; ty < h; ty++)
|
|||
|
{
|
|||
|
for (int tx = 0; tx < w; tx++)
|
|||
|
{
|
|||
|
int subset = partitionTable[ty * 4 + tx];
|
|||
|
RgbaColor8 color = RgbaColor8.FromUInt32(tile[i++] | inverseMask);
|
|||
|
|
|||
|
static void AddIfNew(Span<RgbaColor8> values, RgbaColor8 value, int subset, ref byte count)
|
|||
|
{
|
|||
|
for (int i = 0; i < count; i++)
|
|||
|
{
|
|||
|
if (values[subset * 16 + i] == value)
|
|||
|
{
|
|||
|
return;
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
values[subset * 16 + count++] = value;
|
|||
|
}
|
|||
|
|
|||
|
AddIfNew(colors, color, subset, ref counts[subset]);
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
for (int subset = 0; subset < subsetCount; subset++)
|
|||
|
{
|
|||
|
int offset = subset * 16;
|
|||
|
|
|||
|
RgbaColor8 minColor = minColors[subset];
|
|||
|
RgbaColor8 maxColor = maxColors[subset];
|
|||
|
|
|||
|
ReadOnlySpan<RgbaColor8> subsetColors = colors.Slice(offset, counts[subset]);
|
|||
|
|
|||
|
(RgbaColor8 e0, RgbaColor8 e1) = SelectEndPoints(subsetColors, minColor, maxColor, indexBitCount, colorDepth, alphaDepth, inverseMask);
|
|||
|
|
|||
|
endPoints0[subset] = (endPoints0[subset] & inverseMask) | (e0.ToUInt32() & writeMask);
|
|||
|
endPoints1[subset] = (endPoints1[subset] & inverseMask) | (e1.ToUInt32() & writeMask);
|
|||
|
}
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
private static unsafe void SelectEndPointsFast(
|
|||
|
ReadOnlySpan<byte> partitionTable,
|
|||
|
ReadOnlySpan<uint> tile,
|
|||
|
int w,
|
|||
|
int h,
|
|||
|
int subsetCount,
|
|||
|
ReadOnlySpan<RgbaColor8> minColors,
|
|||
|
ReadOnlySpan<RgbaColor8> maxColors,
|
|||
|
Span<uint> endPoints0,
|
|||
|
Span<uint> endPoints1,
|
|||
|
uint writeMask)
|
|||
|
{
|
|||
|
uint inverseMask = ~writeMask;
|
|||
|
|
|||
|
if (Sse41.IsSupported && w == 4 && h == 4)
|
|||
|
{
|
|||
|
Vector128<byte> row0, row1, row2, row3;
|
|||
|
Vector128<short> ones = Vector128<short>.AllBitsSet;
|
|||
|
|
|||
|
fixed (uint* pTile = tile)
|
|||
|
{
|
|||
|
row0 = Sse2.LoadVector128(pTile).AsByte();
|
|||
|
row1 = Sse2.LoadVector128(pTile + 4).AsByte();
|
|||
|
row2 = Sse2.LoadVector128(pTile + 8).AsByte();
|
|||
|
row3 = Sse2.LoadVector128(pTile + 12).AsByte();
|
|||
|
}
|
|||
|
|
|||
|
Vector128<byte> partitionMask;
|
|||
|
|
|||
|
fixed (byte* pPartitionTable = partitionTable)
|
|||
|
{
|
|||
|
partitionMask = Sse2.LoadVector128(pPartitionTable);
|
|||
|
}
|
|||
|
|
|||
|
for (int subset = 0; subset < subsetCount; subset++)
|
|||
|
{
|
|||
|
RgbaColor32 blockDir = maxColors[subset].GetColor32() - minColors[subset].GetColor32();
|
|||
|
int sum = blockDir.R + blockDir.G + blockDir.B + blockDir.A;
|
|||
|
if (sum != 0)
|
|||
|
{
|
|||
|
blockDir = (blockDir << 6) / new RgbaColor32(sum);
|
|||
|
}
|
|||
|
|
|||
|
Vector128<byte> bd = Vector128.Create(blockDir.GetColor8().ToUInt32()).AsByte();
|
|||
|
|
|||
|
Vector128<short> delta0 = Ssse3.MultiplyAddAdjacent(row0, bd.AsSByte());
|
|||
|
Vector128<short> delta1 = Ssse3.MultiplyAddAdjacent(row1, bd.AsSByte());
|
|||
|
Vector128<short> delta2 = Ssse3.MultiplyAddAdjacent(row2, bd.AsSByte());
|
|||
|
Vector128<short> delta3 = Ssse3.MultiplyAddAdjacent(row3, bd.AsSByte());
|
|||
|
|
|||
|
Vector128<short> delta01 = Ssse3.HorizontalAdd(delta0, delta1);
|
|||
|
Vector128<short> delta23 = Ssse3.HorizontalAdd(delta2, delta3);
|
|||
|
|
|||
|
Vector128<byte> subsetMask = Sse2.Xor(Sse2.CompareEqual(partitionMask, Vector128.Create((byte)subset)), ones.AsByte());
|
|||
|
|
|||
|
Vector128<short> subsetMask01 = Sse2.UnpackLow(subsetMask, subsetMask).AsInt16();
|
|||
|
Vector128<short> subsetMask23 = Sse2.UnpackHigh(subsetMask, subsetMask).AsInt16();
|
|||
|
|
|||
|
Vector128<ushort> min01 = Sse41.MinHorizontal(Sse2.Or(delta01, subsetMask01).AsUInt16());
|
|||
|
Vector128<ushort> min23 = Sse41.MinHorizontal(Sse2.Or(delta23, subsetMask23).AsUInt16());
|
|||
|
Vector128<ushort> max01 = Sse41.MinHorizontal(Sse2.Xor(Sse2.AndNot(subsetMask01, delta01), ones).AsUInt16());
|
|||
|
Vector128<ushort> max23 = Sse41.MinHorizontal(Sse2.Xor(Sse2.AndNot(subsetMask23, delta23), ones).AsUInt16());
|
|||
|
|
|||
|
uint minPos01 = min01.AsUInt32().GetElement(0);
|
|||
|
uint minPos23 = min23.AsUInt32().GetElement(0);
|
|||
|
uint maxPos01 = max01.AsUInt32().GetElement(0);
|
|||
|
uint maxPos23 = max23.AsUInt32().GetElement(0);
|
|||
|
|
|||
|
uint minDistColor = (ushort)minPos23 < (ushort)minPos01
|
|||
|
? tile[(int)(minPos23 >> 16) + 8]
|
|||
|
: tile[(int)(minPos01 >> 16)];
|
|||
|
|
|||
|
// Note that we calculate the maximum as the minimum of the inverse, so less here is actually greater.
|
|||
|
uint maxDistColor = (ushort)maxPos23 < (ushort)maxPos01
|
|||
|
? tile[(int)(maxPos23 >> 16) + 8]
|
|||
|
: tile[(int)(maxPos01 >> 16)];
|
|||
|
|
|||
|
endPoints0[subset] = (endPoints0[subset] & inverseMask) | (minDistColor & writeMask);
|
|||
|
endPoints1[subset] = (endPoints1[subset] & inverseMask) | (maxDistColor & writeMask);
|
|||
|
}
|
|||
|
}
|
|||
|
else
|
|||
|
{
|
|||
|
for (int subset = 0; subset < subsetCount; subset++)
|
|||
|
{
|
|||
|
RgbaColor32 blockDir = maxColors[subset].GetColor32() - minColors[subset].GetColor32();
|
|||
|
blockDir = RgbaColor32.DivideGuarded(blockDir << 6, new RgbaColor32(blockDir.R + blockDir.G + blockDir.B + blockDir.A), 0);
|
|||
|
|
|||
|
int minDist = int.MaxValue;
|
|||
|
int maxDist = int.MinValue;
|
|||
|
|
|||
|
RgbaColor8 minDistColor = default;
|
|||
|
RgbaColor8 maxDistColor = default;
|
|||
|
|
|||
|
int i = 0;
|
|||
|
for (int ty = 0; ty < h; ty++)
|
|||
|
{
|
|||
|
for (int tx = 0; tx < w; tx++, i++)
|
|||
|
{
|
|||
|
if (partitionTable[ty * 4 + tx] != subset)
|
|||
|
{
|
|||
|
continue;
|
|||
|
}
|
|||
|
|
|||
|
RgbaColor8 color = RgbaColor8.FromUInt32(tile[i]);
|
|||
|
int dist = RgbaColor32.Dot(color.GetColor32(), blockDir);
|
|||
|
|
|||
|
if (minDist > dist)
|
|||
|
{
|
|||
|
minDist = dist;
|
|||
|
minDistColor = color;
|
|||
|
}
|
|||
|
|
|||
|
if (maxDist < dist)
|
|||
|
{
|
|||
|
maxDist = dist;
|
|||
|
maxDistColor = color;
|
|||
|
}
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
endPoints0[subset] = (endPoints0[subset] & inverseMask) | (minDistColor.ToUInt32() & writeMask);
|
|||
|
endPoints1[subset] = (endPoints1[subset] & inverseMask) | (maxDistColor.ToUInt32() & writeMask);
|
|||
|
}
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
private static (RgbaColor8, RgbaColor8) SelectEndPoints(
|
|||
|
ReadOnlySpan<RgbaColor8> values,
|
|||
|
RgbaColor8 minValue,
|
|||
|
RgbaColor8 maxValue,
|
|||
|
int indexBitCount,
|
|||
|
int colorDepth,
|
|||
|
int alphaDepth,
|
|||
|
uint alphaMask)
|
|||
|
{
|
|||
|
int n = values.Length;
|
|||
|
int numInterpolatedColors = 1 << indexBitCount;
|
|||
|
int numInterpolatedColorsMinus1 = numInterpolatedColors - 1;
|
|||
|
|
|||
|
if (n == 0)
|
|||
|
{
|
|||
|
return (default, default);
|
|||
|
}
|
|||
|
|
|||
|
minValue = BC67Utils.Quantize(minValue, colorDepth, alphaDepth);
|
|||
|
maxValue = BC67Utils.Quantize(maxValue, colorDepth, alphaDepth);
|
|||
|
|
|||
|
RgbaColor32 blockDir = maxValue.GetColor32() - minValue.GetColor32();
|
|||
|
blockDir = RgbaColor32.DivideGuarded(blockDir << 6, new RgbaColor32(blockDir.R + blockDir.G + blockDir.B + blockDir.A), 0);
|
|||
|
|
|||
|
int minDist = int.MaxValue;
|
|||
|
int maxDist = 0;
|
|||
|
|
|||
|
for (int i = 0; i < values.Length; i++)
|
|||
|
{
|
|||
|
RgbaColor8 color = values[i];
|
|||
|
int dist = RgbaColor32.Dot(BC67Utils.Quantize(color, colorDepth, alphaDepth).GetColor32(), blockDir);
|
|||
|
|
|||
|
if (minDist >= dist)
|
|||
|
{
|
|||
|
minDist = dist;
|
|||
|
}
|
|||
|
|
|||
|
if (maxDist <= dist)
|
|||
|
{
|
|||
|
maxDist = dist;
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
Span<RgbaColor8> palette = stackalloc RgbaColor8[numInterpolatedColors];
|
|||
|
|
|||
|
int distRange = Math.Max(1, maxDist - minDist);
|
|||
|
|
|||
|
RgbaColor32 nV = new RgbaColor32(n);
|
|||
|
|
|||
|
int bestErrorSum = int.MaxValue;
|
|||
|
RgbaColor8 bestE0 = default;
|
|||
|
RgbaColor8 bestE1 = default;
|
|||
|
|
|||
|
Span<int> indices = stackalloc int[n];
|
|||
|
Span<RgbaColor32> colors = stackalloc RgbaColor32[n];
|
|||
|
|
|||
|
for (int maxIndex = numInterpolatedColorsMinus1; maxIndex >= 1; maxIndex--)
|
|||
|
{
|
|||
|
int sumX = 0;
|
|||
|
int sumXX = 0;
|
|||
|
int sumXXIncrement = 0;
|
|||
|
|
|||
|
for (int i = 0; i < values.Length; i++)
|
|||
|
{
|
|||
|
RgbaColor32 color = values[i].GetColor32();
|
|||
|
|
|||
|
int dist = RgbaColor32.Dot(color, blockDir);
|
|||
|
|
|||
|
int normalizedValue = ((dist - minDist) << 6) / distRange;
|
|||
|
int texelIndex = (normalizedValue * maxIndex + 32) >> 6;
|
|||
|
|
|||
|
indices[i] = texelIndex;
|
|||
|
colors[i] = color;
|
|||
|
|
|||
|
sumX += texelIndex;
|
|||
|
sumXX += texelIndex * texelIndex;
|
|||
|
sumXXIncrement += 1 + texelIndex * 2;
|
|||
|
}
|
|||
|
|
|||
|
for (int start = 0; start < numInterpolatedColors - maxIndex; start++)
|
|||
|
{
|
|||
|
RgbaColor32 sumY = new RgbaColor32(0);
|
|||
|
RgbaColor32 sumXY = new RgbaColor32(0);
|
|||
|
|
|||
|
for (int i = 0; i < indices.Length; i++)
|
|||
|
{
|
|||
|
RgbaColor32 y = colors[i];
|
|||
|
|
|||
|
sumY += y;
|
|||
|
sumXY += new RgbaColor32(start + indices[i]) * y;
|
|||
|
}
|
|||
|
|
|||
|
RgbaColor32 sumXV = new RgbaColor32(sumX);
|
|||
|
RgbaColor32 sumXXV = new RgbaColor32(sumXX);
|
|||
|
RgbaColor32 m = RgbaColor32.DivideGuarded((nV * sumXY - sumXV * sumY) << 6, nV * sumXXV - sumXV * sumXV, 0);
|
|||
|
RgbaColor32 b = ((sumY << 6) - m * sumXV) / nV;
|
|||
|
|
|||
|
RgbaColor8 candidateE0 = (b >> 6).GetColor8();
|
|||
|
RgbaColor8 candidateE1 = ((b + m * new RgbaColor32(numInterpolatedColorsMinus1)) >> 6).GetColor8();
|
|||
|
|
|||
|
int pBit0 = GetPBit(candidateE0.ToUInt32(), colorDepth, alphaDepth);
|
|||
|
int pBit1 = GetPBit(candidateE1.ToUInt32(), colorDepth, alphaDepth);
|
|||
|
|
|||
|
int errorSum = BC67Utils.SelectIndices(
|
|||
|
MemoryMarshal.Cast<RgbaColor8, uint>(values),
|
|||
|
candidateE0.ToUInt32(),
|
|||
|
candidateE1.ToUInt32(),
|
|||
|
pBit0,
|
|||
|
pBit1,
|
|||
|
indexBitCount,
|
|||
|
numInterpolatedColors,
|
|||
|
colorDepth,
|
|||
|
alphaDepth,
|
|||
|
alphaMask);
|
|||
|
|
|||
|
if (errorSum <= bestErrorSum)
|
|||
|
{
|
|||
|
bestErrorSum = errorSum;
|
|||
|
bestE0 = candidateE0;
|
|||
|
bestE1 = candidateE1;
|
|||
|
}
|
|||
|
|
|||
|
sumX += n;
|
|||
|
sumXX += sumXXIncrement;
|
|||
|
sumXXIncrement += 2 * n;
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
return (bestE0, bestE1);
|
|||
|
}
|
|||
|
|
|||
|
private static int GetPBit(uint color, int colorDepth, int alphaDepth)
|
|||
|
{
|
|||
|
uint mask = 0x808080u >> colorDepth;
|
|||
|
|
|||
|
if (alphaDepth != 0)
|
|||
|
{
|
|||
|
// If alpha is 0, let's assume the color information is not too important and prefer
|
|||
|
// to preserve alpha instead.
|
|||
|
if ((color >> 24) == 0)
|
|||
|
{
|
|||
|
return 0;
|
|||
|
}
|
|||
|
|
|||
|
mask |= 0x80000000u >> alphaDepth;
|
|||
|
}
|
|||
|
|
|||
|
color &= 0x7f7f7f7fu;
|
|||
|
color += mask >> 1;
|
|||
|
|
|||
|
int onesCount = BitOperations.PopCount(color & mask);
|
|||
|
return onesCount >= 2 ? 1 : 0;
|
|||
|
}
|
|||
|
|
|||
|
private static int GetPBit(uint c0, uint c1, int colorDepth, int alphaDepth)
|
|||
|
{
|
|||
|
// Giving preference to the first endpoint yields better results,
|
|||
|
// might be a side effect of the endpoint selection algorithm?
|
|||
|
return GetPBit(c0, colorDepth, alphaDepth);
|
|||
|
}
|
|||
|
}
|
|||
|
}
|