public static void AddColorGradientDropDownItems(ToolStripItemCollection itemCollection, EventHandler onClick)
{
itemCollection.Clear();
Array values = Enum.GetValues(typeof(ColorGradientEnum));
foreach (ColorGradientEnum colorGradient in values)
{
Bitmap bitmap = GradientBitmap.GenerateBitmap16x16(colorGradient); // bitmap implements IDisposable
ToolStripMenuItem menuItem = new ToolStripMenuItem(colorGradient.GetShowName(), bitmap, onClick) // menuItem implements IDisposable
{
ImageScaling = ToolStripItemImageScaling.None,
Tag = colorGradient
};
itemCollection.Add(menuItem);
}
}
private static Bitmap GenerateBitmap16x16(ColorGradientEnum gradient)
{
int n = 16, m = 16;
Bitmap bitmap = new Bitmap(n, m, PixelFormat.Format32bppArgb);
float[,] values = new float[n, m];
for (int i = 0; i < n; i++)
{
for (int j = 0; j < m; j++)
{
values[i, j] = ((float)i + (float)j) / (float)(n * m);
}
}
GetMinMax(values, out float vMin, out float vMax);
Rectangle rectangle = new Rectangle(0, 0, n, m);
GradientBitmap.FromValues(bitmap, rectangle, (int i, int j) =>
{
float z = (values[i, j] - vMin) / (vMax - vMin);
return(ColorUtilities.GetColor(z, gradient, false));
});
return(bitmap);
}