Interpolation of Isolines

[Medeek]

Computational Geometry Problem:

You have two isolines defined by a finite number of coordinate points (x,y). You then place a random point between these two isolines, at some known coordinate (x1,y1). What is the most accurate method of linear interpolation to determine the value of the point between the isolines?

The inaccuracy in determining the value is due to the approximate nature of the discrete points defining the isolines. However, there are ways to deal with this. I have a devised a fairly simple algorithm for doing this however I would be interested to see what others might come up with and whether it might provide a more accurate and less computationally expensive method than my own.

My first stab at this problem shown below:



I apologize for the image quality, I don't have access to my scanner and my cellphone camera is limited.

This problem is relevant to this forum since it will allow me to automate the mapping process of the Washington Snow Load Analysis and create a fully automatic and interactive online map for Washington State ground snow loads.

[Don_P]

I guess a dumb question, do you not take the most restrictive until you cross the line to the next restrictive... in other words, are you allowed to interpolate?