Based on my understanding, I could input my self-defined triangles to tricontourf so that it will use interpolation to generate contours. But I don’t know the internal logic of interpolation. For example, does it use the triangles’ centre to draw the contour? Also, for interpolation, there are linear interpolation, cosine interpolation, bilinear interpolation, etc. What kind of interpolation do we use for tricontourf?

(I am a starter to this field, please forgive me if the question is stupid)