mesh model face deformation

[trondheimtour]

I created a model of house with 2 openings as doors.. Also I created a physics model of same dimensions similar to the mesh model , ie with 2 openings and the house is of same shape. The physics i applied is Rigidbody . I applied it for the whole mesh . 

I upload the model to secondlife . Then I checked for Render Physics shape . That is showing a closed cube model . The faces I created for my model of the building is all deformed to another triangular shaped faces , and the opening is closed automatically.

What might be the problem ? How can I fix this issue ?

How can I apply physics to a building with rooms .

[Drongle McMahon]

Although some 3D modelling programs can add physics to objects, and collada can specify physics models, these are not used in the SL mesh upload process. Physics information in the Collada file is ignored. Iinstead, the collision shape of an uploaded object can be specified using a mesh on the Physics tab of the upload dialog. If you don't do this, the collision shape will be a single convex hull fitted around the whole visible mesh. That is no good for things you need to go inside.

To cut a long story short, you can make a mesh model* with the minimum number of non-overlapping boxes to give you the desired collision behavior, as discussed in this thread; load that in the Physics tab and click "Analyze". This physics mesh model (for each part if there are multiple objects) must fit the same bounding box as the visible mesh, because otherwise it will be  stretched and/or squeezed to fit it.

It's actually a lot more complicated, as you may discover in many other threads here. with different available approaches and many compliocated factors invilved in optimising physics shape meshes.

You can also try to use the original mesh instead of a specially made physics mesh, but that is very rarely satisfactory, either for function or land impact.

*For multiple object models, there must be as many separate objects as there are separate objects in the visible mesh, with one-to-one correspondence, same sizes and the same order.