private static Bc2Block TryColors(RawBlock4X4Rgba32 rawBlock, ColorRgb565 color0, ColorRgb565 color1, out float error, float rWeight = 0.3f, float gWeight = 0.6f, float bWeight = 0.1f)
{
Bc2Block output = new Bc2Block();
var pixels = rawBlock.AsSpan;
output.color0 = color0;
output.color1 = color1;
var c0 = color0.ToColorRgb24();
var c1 = color1.ToColorRgb24();
ReadOnlySpan <ColorRgb24> colors = stackalloc ColorRgb24[] {
c0,
c1,
c0 *(2.0 / 3.0) + c1 * (1.0 / 3.0),
c0 *(1.0 / 3.0) + c1 * (2.0 / 3.0)
};
error = 0;
for (int i = 0; i < 16; i++)
{
var color = pixels[i];
output.SetAlpha(i, color.A);
output[i] = ColorChooser.ChooseClosestColor4(colors, color, rWeight, gWeight, bWeight, out var e);
error += e;
}
return(output);
}
private static Bc1Block TryColors(RawBlock4X4Rgba32 rawBlock, ColorRgb565 color0, ColorRgb565 color1, out float error, float rWeight = 0.3f, float gWeight = 0.6f, float bWeight = 0.1f)
{
Bc1Block output = new Bc1Block();
var pixels = rawBlock.AsSpan;
output.color0 = color0;
output.color1 = color1;
var c0 = color0.ToColorRgb24();
var c1 = color1.ToColorRgb24();
ReadOnlySpan <ColorRgb24> colors = output.HasAlphaOrBlack ?
stackalloc ColorRgb24[] {
c0,
c1,
c0 *(1.0 / 2.0) + c1 * (1.0 / 2.0),
new ColorRgb24(0, 0, 0)
} : stackalloc ColorRgb24[] {
