/// <summary>
/// Adds a mapping from the given RGB color to the given ARGB color.
/// </summary>
/// <param name="source">The source RGB color.</param>
/// <param name="destination">The destination ARGB color.</param>
/// <exception cref="T:System.ArgumentException">The <paramref name="source"/> and <paramref name="destination"/> colors are
/// identical, and thus this mapping is trivial.</exception>
public void AddMapping(RgbColor source, ArgbColor destination)
{
if (source.ToArgb() == destination.ToArgb())
throw new ArgumentException(
"source and destination colors are identical. Trivial mappings may not be explicitly defined.");
map.Add(source, destination);
}
/// <summary>
/// Builds the color mapping by adding all colors in the given table, and also resolving lookups according to the given alpha map.
/// </summary>
/// <param name="colorTable">The colors that should be added to the current lookup mapping.</param>
/// <param name="alphaMap">The alpha mapping that specifies new ARGB colors that should replace any given RGB colors in the color
/// table.</param>
private void BuildColorMap(ArgbColor[] colorTable, AlphaRemappingTable alphaMap)
{
foreach (ArgbColor sourceArgbColor in colorTable)
{
if (sourceArgbColor.A == 255)
{
RgbColor sourceRgbColor = (RgbColor)sourceArgbColor;
Color sourceColor = Color.FromArgb(sourceRgbColor.ToArgb());
if (!colorMappingTable.ContainsKey(sourceColor))
{
if (!alphaMap.TryGetMapping(sourceRgbColor, out ArgbColor desiredArgbColor))
{
desiredArgbColor = sourceArgbColor;
}
colorMappingTable.Add(sourceColor, Color.FromArgb(desiredArgbColor.ToArgb()));
}
}
}
}
