Terrain Editing - once again

[Andreaz]

Thanks for useful hints. I'm going to write some code now using your and mine ideas. I'll let you know later about the result - I'll post the code then.

.: EDIT !! :.
I did some changes, but I don't know why my "favorite" error occurs (line 26. :?
http://www.glsoftworks.pastebin.com/f5051d109

Most likely it's related to
Data.Heights[X, Y]

And as i said, displaylist doesnt gonna help you, especially when you're goint to edit the terrain, displaylists is static by nature. Use vertex arrays as in you last code instead.

[User137]

Forgot to create DisplayList first?

DisplayList:=glGenLists(1);
glNewList(DisplayList, GL_COMPILE);
...

[Brainer]

Thanks, User137. Here is the newest try. This time nothing gets rendered. I dunno why. Could you take a look at the code? Sorry for my lame questions, but I'm not that advanced and I'd like to learn more by asking as much as possible.
http://www.glsoftworks.pastebin.com/d69ddc039

[User137]

I don't see anything odd, i trust you've tested all the numeric things to work before, and couldn't help there without testing in delphi. But as perfectionist as i can be, there is something

1.GL_COMPILE_AND_EXECUTE could be used to replace GL_COMPILE + glCallList as it's also faster way and simplify code.

2.procedure TCell.RenderCell; creates displaylist but does not render it. Without seeing the main program this would explain the non showing only if render was not in loop (but i guess you got a timer so this point is non valid...).

3.Extra variables controlling other variables sometimes make a mess. glGenLists(1) results a number that is always > 0, so uninitialized list would result 0.
[pascal]if GotDisplayList then
// means the same as
if DisplayList>0 then[/pascal]

[Brainer]

Thank you for your tips! I'll do the changes you mentioned tomorrow and let you know.