A few questions with GLscene

[Brainer]

Hello!

1) Is it possible to pass a 3D array to the terrain renderer to be processed, rather than using a bitmap HDS

Yip, it is possible, yet I have never done it before. The best example of this is demo called synthterr.

2) is it possible to directly dictate the coordinate of each corner of a cube, so as to make elongated cubes?

I don't really understand your question, but if you want to make cuboids, just scale the cube using Scale property. Set it fx. to (1.0; 3.0; 2.0).

3) How does the BSP system differ than the use of polygons and cubes?

Here

4) when create a cube during run time by
cube:=TGLcube(dummycube1.addnewchild(tglcube))
how can you refer to each indivial cube i.e. the 3rd or 20th cube?

You can simply name each of the cubes and then select them by their names. Or use this:
[pascal]
var
I: Integer;
TheCube: TGLCube;
begin
TheCube := nil;
for I := 0 to GLDummyCube1.Count -1 do
if (GLDummyCube1.Children[I] is TGLCube) then
if (I = 2) then
begin
TheCube := (GLDummyCube1.Children[I] as TGLCube);
break;
end;

if Assigned(TheCube) then
TheCube.Material.FrontProperties.Diffuse.Color := clrRed;
[/pascal]

5) And for a non glscene question, is it only and Delphi 7 and below which are incompatible with vista or are all version of delphi 2003 etc.. incompatilble?

I once had D7 working under Vista, so it seems that it's compatible.