Re: [Widelands-public] Widelands design choices

[Stefan <st...@up...>]

> What
> I am particularly interested in is 2 things: ...
> 2. How does Widelands store and display terrain? Is it a straightforwar=
d
> matrix with height values, a hexagonal structure or something other fan=
cy?
> And how is it displayed? Does it use hermite or spline or something els=
e?

Yes, at this time terrain is a simple matrix with height values. The squa=
res=20
(parallelograms, rather) between four points are split into two triangles=
=20
which are rendered the usual way, i.e. using gouraud shading and affine=20
texture mapping. Note that currently hardware rendering support (like usi=
ng=20
OpenGL) is neither implemented nor wanted as far as I understand.

That means that light calculations are done for the corners. Adjacent=20
triangles' normal vectors are averaged to get an estimate of the "normal"=
 in=20
these points. The shade value basically is the scalar product with the li=
ght=20
vector (which is constant) then. These calculations are done in advance a=
nd=20
updated whenever a point's height changes.

I hope this helps.

Regards,
Stefan Boettner