Generate Color Gradient in C#

Question

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 1

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);
    // ... and for B, G
    colorList.Add(Color.FromArgb(rAverage, gAverage, bAverage));
}

Answer 2

You need to make the change on the three components - Red Green and Blue at the same time and then use the result.

Answer 3

Maybe this function can help:

public IEnumerable<Color> GetGradients(Color start, Color end, int steps)
{
    Color stepper = Color.FromArgb((byte)((end.A - start.A) / (steps - 1)),
                                   (byte)((end.R - start.R) / (steps - 1)),
                                   (byte)((end.G - start.G) / (steps - 1)),
                                   (byte)((end.B - start.B) / (steps - 1)));

    for (int i = 0; i < steps; i++)
    {
        yield return Color.FromArgb(start.A + (stepper.A * i),
                                    start.R + (stepper.R * i),
                                    start.G + (stepper.G * i),
                                    start.B + (stepper.B * i));
    }
}