/// <summary>
/// Accesses pixel at [i, j]
/// </summary>
/// <param name="i">row</param>
/// <param name="j">column</param>
/// <param name="part">part of colour accessed</param>
/// <returns>Selected part of pixel at [i, j]</returns>
internal byte this[int i, int j, ColourPart part]
{
get
{
if (part == ColourPart.Alpha && bytesPerPixel == 3)
{
throw new ArgumentException("Error: attempt to read alpha channel which is not provided.");
}
if (i < 0 || i >= height || j < 0 || j >= width)
{
return(0);
}
int start = (int)(offset + i * actualWidth + j * bytesPerPixel);
int index = start + bytesPerPixel - (int)part - 1;
if (index < 0 || index >= data.Length)
{
throw new IndexOutOfRangeException($"Index out of range: i={i}, j={j}, part={part}");
}
return(data[index]);
}
set
{
if (part == ColourPart.Alpha && bytesPerPixel == 3)
{
throw new ArgumentException("Error: attempt to write to alpha channel which is not provided.");
}
if (i < 0 || i >= height || j < 0 || j >= width)
{
throw new ArgumentOutOfRangeException($"Error: index ({i}, {j}, {part}) is out of range");
}
int start = (int)(offset + i * actualWidth + j * bytesPerPixel);
int index = start + bytesPerPixel - (int)part - 1;
data[index] = value;
}
}
public ImageAddress(int index, int jndex, ColourPart colourPart)
{
Index = index;
Jndex = jndex;
ColourPart = colourPart;
}
