[Bug 10636] simcity 4 3D objects become invisible

http://bugs.winehq.org/show_bug.cgi?id=10636

--- Comment #25 from Pierre Willenbrock   2009-06-02 16:05:50 ---
So, i figured out that although a can now compile things for windows, i am
still lacking the needed knowledge about Direct3D7. Instead i am now looking
over the logs, and found that the game tries to do Blts from/to the
z-buffer(while BeginScene is in effect, but avoiding that early bail-out is
easy).

I think this works like this: There is an offscreen z-buffer(0x160d58 in my
log) and and the onscreen z-buffer(0x1f28d0).
If the offscreen z-buffer is uninitialised, the ground tiles etc are rendered,
then the onscreen z-buffer blted to the offscreen z-buffer. 
After this, whenever a new frame needs to be rendered, the offscreen z-buffer
is blted over the onscreen z-buffer.
When moving the viewarea around, the offscreen z-buffer is first blted to the
onscreen z-buffer at the new position, the missing parts rendered and then
blted back to the offscreen z-buffer.
(I think the back-buffer is handled in a similar way.)

Now, this all fails, because 
a) the game tries to do this while BeginScene is active
b) the z-buffer-blts are not implemented.