Production ready game models.

dream16

Hello guys, i search on google for my answer but no hope so please help me this question, it may be a stupid question . Do a production ready game model need to be triangulated ?

Kwramm

no. (disclaimer: there can always be exceptions...it's game dev, after all )
The exporter / engine will triangulate for you automatically.
Source files should not be triangulated because it makes working with them more difficult. However, sometimes it can help to manually triangulate problem areas, e.g. parts that don't deform properly, or that show weird lighting/shading.

dream16

@Kwramm : Thank you so much.

I have a lowpoly model with distortion problems. Can i duplicate the lowpoly model(same UV) and change geometry in the new model to fix distortions then bake normal map , after that use the normal map for the old model (geometries not changed). Or i have to change geometry on the old model and bake normal map for itself.

Eric Chadwick

dream16 wrote: »

I have a lowpoly model with distortion problems. Can i duplicate the lowpoly model(same UV) and change geometry in the new model to fix distortions then bake normal map , after that use the normal map for the old model (geometries not changed). Or i have to change geometry on the old model and bake normal map for itself.

Depends. If the UV is unique for the model (a prop or weapon for example) then it will usually cause lighting errors if you change the UVs or triangles after baking.

If the UV is tiled (landscape, wall, etc.) then you can change things after baking without repercussion.

Some people use a technique where they change the topology for the bake, and discard that before exporting the model. This is fragile though.
http://www.polycount.com/forum/showthread.php?t=144715

pior

(disclaimer: there can always be exceptions...it's game dev, after all )

Exactly For instance, non-triangulated meshes cause problem with tangent-space normalmap baking, since there is no way to guarantee that the tool used for baking triangulates things the same way as the engine the model is ultimately exported to. Now there are workaround around this (like applying a triangulation modifier/node enabled on for export but turned off for rigging).

To make things worse, some 3d apps also dynamically edit hidden triangulation edges in realtime when a mesh is deformed, which can cause a whole lot of issues especially when a model is tweaked after the fact (I've seen cases where this broke morph targets, for instance). The lingering issue is that a lot of people down the art pipeline might not notice these problems or think that things looks "good enough", but then problems pile up and become harder and harder to fix.

So yeah, triangulating before baking is actually very important, especially when hard surface models are involved.

FourtyNights

pior wrote: »

...like applying a triangulation modifier/node enabled on for export but turned off for rigging.

Just like how I work in Blender with characters. Rigging with the triangulate modifier on the stack for viewing normal maps correctly, and painting weights on the quad mesh.