Generate Color Gradient in C#

Graviton picture Graviton · Jan 6, 2010 · Viewed 41.7k times · Source

My question here is similar to the question here, except that I am working with C#.

I have two colors, and I have a predefine steps. How to retrieve a list of Colors that are the gradients between the two?

This is an approach that I tried, which didn't work:

int argbMax = Color.Chocolate.ToArgb();
int argbMin = Color.Blue.ToArgb();
var colorList = new List<Color>();

for(int i=0; i<size; i++)
{
    var colorAverage= argbMin + (int)((argbMax - argbMin) *i/size);
    colorList.Add(Color.FromArgb(colorAverage));
}

If you try the above code, you will find that a gradual increase in argb doesn't correspond to a visual gradual increase in the color.

Any idea on this?

Answer

David M picture David M · Jan 6, 2010

You will have to extract the R, G, B components and perform the same linear interpolation on each of them individually, then recombine.

int rMax = Color.Chocolate.R;
int rMin = Color.Blue.R;
// ... and for B, G
var colorList = new List<Color>();
for(int i=0; i<size; i++)
{
    var rAverage = rMin + (int)((rMax - rMin) * i / size);
    var gAverage = gMin + (int)((gMax - gMin) * i / size);
    var bAverage = bMin + (int)((bMax - bMin) * i / size);
    colorList.Add(Color.FromArgb(rAverage, gAverage, bAverage));
}