terminal/src/buffer/out/TextColor.cpp
Leonard Hecker 769600bc59 wip
2021-07-24 00:04:21 +02:00

152 lines
7 KiB
C++

// Copyright (c) Microsoft Corporation.
// Licensed under the MIT license.
#include "precomp.h"
#include "TextColor.h"
// clang-format off
// A table mapping 8-bit RGB colors, in the form RRRGGGBB,
// down to one of the 16 colors in the legacy palette.
constexpr std::array<BYTE, 256> CompressedRgbToIndex16 = {
0, 1, 1, 9, 0, 0, 1, 1, 2, 1, 1, 1, 2, 8, 1, 9,
2, 2, 3, 3, 2, 2, 11, 3, 10, 10, 11, 11, 10, 10, 10, 11,
0, 5, 1, 1, 0, 0, 1, 1, 8, 1, 1, 1, 2, 8, 1, 9,
2, 2, 3, 3, 2, 2, 11, 3, 10, 10, 10, 11, 10, 10, 10, 11,
5, 5, 5, 1, 4, 5, 1, 1, 8, 8, 1, 9, 2, 8, 9, 9,
2, 2, 3, 3, 2, 2, 11, 3, 10, 10, 11, 11, 10, 10, 10, 11,
4, 5, 5, 1, 4, 5, 5, 1, 8, 5, 5, 1, 8, 8, 9, 9,
2, 2, 8, 9, 10, 2, 11, 3, 10, 10, 11, 11, 10, 10, 10, 11,
4, 13, 5, 5, 4, 13, 5, 5, 4, 13, 13, 13, 6, 8, 13, 9,
6, 8, 8, 9, 10, 10, 11, 3, 10, 10, 11, 11, 10, 10, 10, 11,
4, 13, 13, 13, 4, 13, 13, 13, 4, 12, 13, 13, 6, 12, 13, 13,
6, 6, 8, 9, 6, 6, 7, 7, 10, 14, 14, 7, 10, 10, 14, 11,
4, 12, 13, 13, 4, 12, 13, 13, 4, 12, 13, 13, 6, 12, 12, 13,
6, 6, 12, 7, 6, 6, 7, 7, 6, 14, 14, 7, 14, 14, 14, 15,
12, 12, 13, 13, 12, 12, 13, 13, 12, 12, 12, 13, 12, 12, 12, 13,
6, 12, 12, 7, 6, 6, 7, 7, 6, 14, 14, 7, 14, 14, 14, 15
};
// A table mapping indexed colors from the 256-color palette,
// down to one of the 16 colors in the legacy palette.
constexpr std::array<BYTE, 256> Index256ToIndex16 = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
0, 1, 1, 1, 9, 9, 2, 1, 1, 1, 1, 1, 2, 2, 3, 3,
3, 3, 2, 2, 11, 11, 3, 3, 10, 10, 11, 11, 11, 11, 10, 10,
10, 10, 11, 11, 5, 5, 5, 5, 1, 1, 8, 8, 1, 1, 9, 9,
2, 2, 3, 3, 3, 3, 2, 2, 11, 11, 3, 3, 10, 10, 11, 11,
11, 11, 10, 10, 10, 10, 11, 11, 4, 13, 5, 5, 5, 5, 4, 13,
13, 13, 13, 13, 6, 8, 8, 8, 9, 9, 10, 10, 11, 11, 3, 3,
10, 10, 11, 11, 11, 11, 10, 10, 10, 10, 11, 11, 4, 13, 13, 13,
13, 13, 4, 12, 13, 13, 13, 13, 6, 6, 8, 8, 9, 9, 6, 6,
7, 7, 7, 7, 10, 14, 14, 14, 7, 7, 10, 10, 14, 14, 11, 11,
4, 12, 13, 13, 13, 13, 4, 12, 13, 13, 13, 13, 6, 6, 12, 12,
7, 7, 6, 6, 7, 7, 7, 7, 6, 14, 14, 14, 7, 7, 14, 14,
14, 14, 15, 15, 12, 12, 13, 13, 13, 13, 12, 12, 12, 12, 13, 13,
6, 12, 12, 12, 7, 7, 6, 6, 7, 7, 7, 7, 6, 14, 14, 14,
7, 7, 14, 14, 14, 14, 15, 15, 0, 0, 0, 0, 0, 0, 8, 8,
8, 8, 8, 8, 8, 8, 8, 8, 7, 7, 7, 7, 7, 7, 15, 15
};
// clang-format on
// We should only need 4B for TextColor. Any more than that is just waste.
static_assert(sizeof(TextColor) == 4);
// Assert that the use of memcmp() for comparisons is safe.
static_assert(std::has_unique_object_representations_v<TextColor>);
// Method Description:
// - Retrieve the real color value for this TextColor.
// * If we're an RGB color, we'll use that value.
// * If we're an indexed color table value, we'll use that index to look up
// our value in the provided color table.
// - If brighten is true, and we've got a 16 color index in the "dark"
// portion of the color table (indices [0,7]), then we'll look up the
// bright version of this color (from indices [8,15]). This should be
// true for TextAttributes that are "Bold" and we're treating bold as
// bright (which is the default behavior of most terminals.)
// * If we're a default color, we'll return the default color provided.
// Arguments:
// - colorTable: The table of colors we should use to look up the value of
// an indexed attribute from.
// - defaultColor: The color value to use if we're a default attribute.
// - brighten: if true, we'll brighten a dark color table index.
// Return Value:
// - a COLORREF containing the real value of this TextColor.
COLORREF TextColor::GetColor(const std::array<COLORREF, 256>& colorTable,
const COLORREF defaultColor,
bool brighten) const noexcept
{
if (IsDefault())
{
if (brighten)
{
// See MSFT:20266024 for context on this fix.
// Additionally todo MSFT:20271956 to fix this better for 19H2+
// If we're a default color, check to see if the defaultColor exists
// in the dark section of the color table. If it does, then chances
// are we're not a separate default color, instead we're an index
// color being used as the default color
// (Settings::_DefaultForeground==INVALID_COLOR, and the index
// from _wFillAttribute is being used instead.)
// If we find a match, return instead the bright version of this color
#ifdef _M_AMD64
const auto needle = _mm_set1_epi32(defaultColor);
const auto haystack1 = _mm_loadu_si128(reinterpret_cast<const __m128i*>(colorTable.data() + 0));
const auto haystack2 = _mm_loadu_si128(reinterpret_cast<const __m128i*>(colorTable.data() + 4));
const auto result1 = _mm_cmpeq_epi32(haystack1, needle);
const auto result2 = _mm_cmpeq_epi32(haystack2, needle);
const auto shuffle16to8 = _mm_setr_epi8(0, 2, 4, 6, 8, 10, 12, 14, -1, -1, -1, -1, -1, -1, -1, -1);
const auto result = _mm_shuffle_epi8(_mm_packs_epi16(result1, result2), shuffle16to8);
const auto combined = _mm_movemask_epi8(result);
unsigned long index;
return _BitScanForward(&index, combined) ? til::at(colorTable, index + 8) : defaultColor;
#else
for (size_t i = 0; i < 8; i++)
{
if (til::at(colorTable, i) == defaultColor)
{
return til::at(colorTable, i + 8);
}
}
#endif
}
return defaultColor;
}
else if (IsRgb())
{
return GetRGB();
}
else
{
return til::at(colorTable, IsIndex16() & brighten ? _index : _index | 8);
}
}
// Method Description:
// - Return a legacy index value that best approximates this color.
// Arguments:
// - defaultIndex: The index to use for a default color.
// Return Value:
// - an index into the 16-color table
BYTE TextColor::GetLegacyIndex(const BYTE defaultIndex) const noexcept
{
switch (_meta)
{
case ColorType::IsDefault:
return defaultIndex;
case ColorType::IsIndex16:
return _index;
case ColorType::IsIndex256:
return Index256ToIndex16[_index];
default:
// We compress the RGB down to an 8-bit value and use that to
// lookup a representative 16-color index from a hard-coded table.
const BYTE compressedRgb = (_red & 0b11100000) |
((_green >> 3) & 0b00011100) |
(_blue >> 6);
return CompressedRgbToIndex16[compressedRgb];
}
}