http://www.fsdeveloper.com/forum/threads/shadow-does-not-show-on-the-bridge.438369/#post-754995
3. For
counter-clock-wise issue. I don't think it is. But I am not quite understand(ing) this issue. It happen on exclusion that draw counter clockwise, isn't it?
4. MCX might be the problem? I don't know how to fix that.
Hi Tic:
Glad to see you got the anomalous aircraft ground shadow display sorted out.
Regarding the required vertex coordinate draw sequence / winding direction to define "Front" surfaces (...so that they should
not be "culled" as a "Back" surface) via the DirectX rendering subsystem underlying most 3D model graphic rendering in Windows simulations including
FS, the Windows DirectX-9 documentation confirms that one should draw them in a
clock-wise order.
Thus, if one purposely wishes to
prevent "normal" rendering of a texture image mapped onto a 3D model, one draws that surface in a
counter-clockwise vertex winding direction; this MSDN Direct3D-9 document explains that particular option:
"
Culling State (Direct3D 9)
To improve rendering performance, you can cull out (or remove) a primitive that faces away from the camera. For single-sided primitives, this saves rendering time because a back-face is not visible. To enable culling, you need to know the winding order of the vertices (typically counter-clockwise). This example will remove any primitive whose back face is facing forward (given a counter-clockwise winding order)"
https://msdn.microsoft.com/en-us/library/windows/desktop/bb204882(v=vs.85).aspx
PS: Whereas
Sketchup by default automatically creates 2-sided (Front and Back) faces and applies a default White material to the 'Front' face, and a light Blue to the 'Back' face, IIRC, in
3DSMAX /
GMAX one must manually create any 'Back' faces.
I'm not certain yet as to what Blender does in this regard.
However, IIUC (as a non-user of either
3DSMAX /
GMAX), one can still draw vertices for a face in either a clock-wise
or counter-clockwise direction.
I am not sure whether
3DSMAX /
GMAX provides any visual clues as to such a "winding direction" for faces in a single-sided 3D model (such as is otherwise provided automatically by
Sketchup).
But AFAIK, 3D models which have such surface geometry (whether texture-mapped or not), will have the clock-wise or counter-clockwise direction of vertex coordinate sequence preserved by the native export to any file format, and via the FS SDK compilers (and AFAIK, this is also the case when they are imported and then subsequently re-exported by MCX).
So, we must all be aware of how we sequence vertex coordinates when drawing our 3D models, as our 3D geometry will have the clock-wise or counter-clockwise winding direction preserved ...with a subsequent impact on the resulting run time render by Windows' DirectX sub-system.
And of course this same Caveat-
to be aware of how we sequence vertex coordinates- also applies to our work-flow when creating poly-line and polygon scenery content for FS.
Hope this helps to explain how '3D vertex coordinate winding direction' works in FS via DirectX.
GaryGB
)
