PathGradientBrush.SetBlendTriangularShape Method (Single)
Creates a gradient with a center color and a linear falloff to one surrounding color.
Assembly: System.Drawing (in System.Drawing.dll)
A value from 0 through 1 that specifies where, along any radial from the center of the path to the path's boundary, the center color will be at its highest intensity. A value of 1 (the default) places the highest intensity at the center of the path.
If there is more than one color in the SurroundColors array, the first color in the array is used for the ending color. The colors specified in this array are used for discrete points on the brush's boundary path.
Available since 1.1