[ClockWatcher]

Here's one question to start with: if there's a texture, one pixel from it corresponds to how many meter on the map?

Looking at some of the info posted, colour values R:255 G:255 B:255 is equals to 13 000 ft high. If that is correct then each 50 ft increment in height is approximately equal to increments of 1 in the RGB value. This would tie in with certain printed maps which have contours at 50ft intervals, but this depends on the printed map scale.

13 000ft approx 4000 m
50 ft approx 15m

I need to sit down and do a graded map from RGB = 0 to RGB = 255 and see if the slope is linear or curved. If linear then each increase of 1 in RGB will be an equal increase in height. If the slope is curved though, then it is not a simple calculation. And if I park my plane on the top I will get the height when RGB=255!

May try this when I get home from work tonight.[/quote]