Generating a Linear Gradient

Introduction

• Creates a linear gradient between two color values and stores it in a mat with a single row

Code

public static unsafe Mat CreateLinearGradient(int width, Color lowColor, Color highColor)
{
    Mat gradient = new Mat(1, width, DepthType.Cv8U, 3);
    byte* kGradient = (byte*)gradient.DataPointer.ToPointer();
    
    byte rStart = lowColor.R;
    byte gStart = lowColor.G;
    byte bStart = lowColor.B;

    float rDelta = (highColor.R - lowColor.R) / (width - 1f);
    float gDelta = (highColor.G - lowColor.G) / (width - 1f);
    float bDelta = (highColor.B - lowColor.B) / (width - 1f);

    for (int i = 0; i < width; i++)
    {
        *kGradient++ = (byte)(bStart + bDelta * i);
        *kGradient++ = (byte)(gStart + gDelta * i);
        *kGradient++ = (byte)(rStart + rDelta * i);
    }

    return gradient;
}

Usage

static void Main(string[] args)
{
    Mat gradient = CreateLinearGradient(256, Color.Red, Color.Blue);
    CvInvoke.Imshow("test", gradient);
    CvInvoke.WaitKey(0);
}

Output