private static void GetBlock4Alpha(Binary binary, int[,] alphas, int[] colorVals)
{
ulong n = binary.ReadUInt64();
for (int i = 0; i < 4; i++)
{
for (int j = 0; j < 4; j++)
{
alphas[j, i] = (int)((n & 15) * 17);
n >>= 4;
}
}
ushort c0 = binary.ReadUInt16();
ushort c1 = binary.ReadUInt16();
Color[] color = new Color[4];
color[0] = ColorHelp.From565(c0);
color[1] = ColorHelp.From565(c1);
color[2] = ColorHelp.MixRatio(color[0], color[1], 2, 1);
color[3] = ColorHelp.MixRatio(color[0], color[1], 1, 2);
for (int i = 0; i < 4; i++)
{
colorVals[i] = color[i].ToArgb() & 0x00FFFFFF;
}
}
private static void GetBlock8RelAlpha(Binary binary, int[,] alphas, int[] colorVals)
{
ulong n = binary.ReadUInt64();
int a0 = (byte)(n & 0xFF);
n >>= 8;
int a1 = (byte)(n & 0xFF);
n >>= 8;
int[] a = new int[8];
if (a0 <= a1)
{
a[0] = a0;
a[1] = a1;
a[2] = (4 * a0 + 1 * a1) / 5;
a[3] = (3 * a0 + 2 * a1) / 5;
a[4] = (2 * a0 + 3 * a1) / 5;
a[5] = (1 * a0 + 4 * a1) / 5;
a[6] = 0;
a[7] = 255;
}
else
{
a[0] = a0;
a[1] = a1;
a[2] = (6 * a0 + 1 * a1) / 7;
a[3] = (5 * a0 + 2 * a1) / 7;
a[4] = (4 * a0 + 3 * a1) / 7;
a[5] = (3 * a0 + 4 * a1) / 7;
a[6] = (2 * a0 + 5 * a1) / 7;
a[7] = (1 * a0 + 6 * a1) / 7;
}
for (int i = 0; i < 4; i++)
{
for (int j = 0; j < 4; j++)
{
alphas[j, i] = a[n & 7];
n >>= 3;
}
}
ushort c0 = binary.ReadUInt16();
ushort c1 = binary.ReadUInt16();
Color[] color = new Color[4];
color[0] = ColorHelp.From565(c0);
color[1] = ColorHelp.From565(c1);
color[2] = ColorHelp.MixRatio(color[0], color[1], 2, 1);
color[3] = ColorHelp.MixRatio(color[0], color[1], 1, 2);
for (int i = 0; i < 4; i++)
{
colorVals[i] = color[i].ToArgb() & 0x00FFFFFF;
}
}
private static void GetBlockNoAlpha(Binary binary, int[,] alphas, int[] colorVals)
{
ushort c0 = binary.ReadUInt16();
ushort c1 = binary.ReadUInt16();
Color[] color = new Color[4];
color[0] = ColorHelp.From565(c0);
color[1] = ColorHelp.From565(c1);
if (c0 <= c1)
{
color[2] = ColorHelp.MixRatio(color[0], color[1], 1, 1);
color[3] = Color.FromArgb(0, 0, 0);
}
else
{
color[2] = ColorHelp.MixRatio(color[0], color[1], 2, 1);
color[3] = ColorHelp.MixRatio(color[0], color[1], 1, 2);
}
for (int i = 0; i < 4; i++)
{
colorVals[i] = color[i].ToArgb();
}
}
private static (ushort, ushort, int[, ]) ReduceColors4(Color[] colors)
{
int maxDist = 0;
int maxi0 = 0, maxi1 = 0;
for (int i1 = 0; i1 < 16; i1++)
{
for (int i2 = 0; i2 < i1; i2++)
{
int dist =
(colors[i1].R - colors[i2].R) * (colors[i1].R - colors[i2].R) +
(colors[i1].G - colors[i2].G) * (colors[i1].G - colors[i2].G) +
(colors[i1].B - colors[i2].B) * (colors[i1].B - colors[i2].B);
if (dist >= maxDist)
{
maxDist = dist;
maxi0 = i1;
maxi1 = i2;
}
}
}
ushort b0 = ColorHelp.To565(colors[maxi0]);
ushort b1 = ColorHelp.To565(colors[maxi1]);
ushort b0new, b1new;
Color[] newColor = new Color[4];
if (b0 < b1)
{
b0new = b1;
b1new = b0;
}
else
{
b0new = b0;
b1new = b1;
}
newColor[0] = ColorHelp.From565(b0new);
newColor[1] = ColorHelp.From565(b1new);
newColor[2] = ColorHelp.MixRatio(newColor[0], newColor[1], 2, 1);
newColor[3] = ColorHelp.MixRatio(newColor[0], newColor[1], 1, 2);
int[,] colorIndex = new int[4, 4];
for (int i = 0; i < 16; i++)
{
int minDist = 3 * 256 * 256;
int minj = 0;
for (int j = 0; j < 4; j++)
{
int dist =
(colors[i].R - newColor[j].R) * (colors[i].R - newColor[j].R) +
(colors[i].G - newColor[j].G) * (colors[i].G - newColor[j].G) +
(colors[i].B - newColor[j].B) * (colors[i].B - newColor[j].B);
if (dist < minDist)
{
minDist = dist;
minj = j;
}
}
colorIndex[i % 4, i / 4] = minj;
}
return(b0new, b1new, colorIndex);
}