/**
* mix two surface colors, eg. for transparent texture overlays
* @param topColor
* @param bottomColor
* @return
*/
public static WideColor MixSurfaceSurface(this WideColor topColor, WideColor bottomColor)
{
// the two most common cases: top color is fully opaque or fully transparent
if (topColor.A >= 0xFF)
{
return(topColor);
}
if (topColor.A == 0x00)
{
return(bottomColor);
}
// we know that a is smaller than 255 already so we don't have to check
double alpha = topColor.A / 256.0;
double invAlpha = 1 - alpha;
return(new WideColor
{
A = (ushort)(topColor.A + bottomColor.A * invAlpha),
R = (ushort)(topColor.R * alpha + bottomColor.R * invAlpha),
G = (ushort)(topColor.G * alpha + bottomColor.G * invAlpha),
B = (ushort)(topColor.B * alpha + bottomColor.B * invAlpha)
});
}
public static Color To8Bit(this WideColor c)
{
return(new Color
{
A = (byte)MathHelper.Clamp(c.A, byte.MinValue, byte.MaxValue),
R = (byte)MathHelper.Clamp(c.R, byte.MinValue, byte.MaxValue),
G = (byte)MathHelper.Clamp(c.G, byte.MinValue, byte.MaxValue),
B = (byte)MathHelper.Clamp(c.B, byte.MinValue, byte.MaxValue)
});
}
/**
* mix a surface color with a light color
* @param surfaceColor
* @param lightColor
* @return
*/
public static WideColor MixSurfaceLight(this WideColor surfaceColor, WideColor lightColor)
{
// weight the surface colors with the light colors (multiply, divide by normalized maximum)
return(new WideColor
{
A = surfaceColor.A,
R = (ushort)(surfaceColor.R * lightColor.R / 256),
G = (ushort)(surfaceColor.G * lightColor.G / 256),
B = (ushort)(surfaceColor.B * lightColor.B / 256)
});
}
public static WideColor MixLightLight(this WideColor l1, WideColor l2)
{
return(l1 + l2);
}
public static ushort GetMax(this WideColor c)
{
return(System.Math.Max(c.R, System.Math.Max(c.G, c.B)));
}
public static WideColor Scale(this WideColor c1, double d)
{
return(c1 * d);
}