[SOLVED] Collision Volumes on Static Meshes

[fallingbrickwork]

Hi all,

I am creating some static meshes in Modo for use with UDK and i'm having a few problems with the collision hull versions of the models.

Everything is working fine and i'm importing the models without any problems BUT... i'm finding that the collision hulls need to be quite large to register within UDK.

Example...

I have a wall section which is a flat plane. I'm creating a child mesh called UCX, but unless the box that is in this is 1m wide it doesn't register in UDK as a collision mesh?!... this 1 m is fine in most cases, but my level double backs on its self in a few places and this 1m mesh goes over into a different section.

Is this correct?? is there anyway that a collision mesh can be generated within UDK for these static meshes when things are tight? (i dont always want a metre width box for a pipe that is 10cm diameter).

Regards,
Matt.

[strangelet]

first off, yes ive had problems where very small meshes' collision has been borked on import. mostly however this was because iw as importing at truly tiny scale. are you sure you're importing them at the right *world scale* ? if you have to scale up your meshes by a large amount when you place them in your level this is a good indicator that you can probably import them at a larger scale.

you could also try using _MCDCX collision meshes. these have to be primitives with no non-planar polygons in them (mainly boxes) i dont know the full restrictions on mcdcx, prolly can find out out in the udn

the staticmesh editor has a detailed set of collision creation tools, including Auto-Convex which is a pretty good shape interpretation tool which can assess meshes and create multiple collision primitives for oddly shaped stuff. its not perfect, and for very complex models or models which are critical to player movement (large buildings for example) , building collision manually is always better. but the tools are very good for most purposes.

in addition to this, the same tools can be used to create Blocking Volumes in the level itself. this is insanely useful - many times you will create a level with many small lumpy objects that the player will never go anywhere near.

with the Blocking Volume Creation tools available in the rightclick menu, you can select one or many meshes and use either simple Bounding Box or the AutoConvex tool to create a single blockingvolume to surround them all. when meshes are selected and the blockingvolume creation tools used on them, their collision is switched off, saving loads of data space in your map.

[fallingbrickwork]

first off, yes ive had problems where very small meshes' collision has been borked on import. mostly however this was because iw as importing at truly tiny scale. are you sure you're importing them at the right *world scale* ? if you have to scale up your meshes by a large amount when you place them in your level this is a good indicator that you can probably import them at a larger scale.

you could also try using _MCDCX collision meshes. these have to be primitives with no non-planar polygons in them (mainly boxes) i dont know the full restrictions on mcdcx, prolly can find out out in the udn

the staticmesh editor has a detailed set of collision creation tools, including Auto-Convex which is a pretty good shape interpretation tool which can assess meshes and create multiple collision primitives for oddly shaped stuff. its not perfect, and for very complex models or models which are critical to player movement (large buildings for example) , building collision manually is always better. but the tools are very good for most purposes.

in addition to this, the same tools can be used to create Blocking Volumes in the level itself. this is insanely useful - many times you will create a level with many small lumpy objects that the player will never go anywhere near.

with the Blocking Volume Creation tools available in the rightclick menu, you can select one or many meshes and use either simple Bounding Box or the AutoConvex tool to create a single blockingvolume to surround them all. when meshes are selected and the blockingvolume creation tools used on them, their collision is switched off, saving loads of data space in your map.

Many thanks for this... and you are correct, i am scaling up meshes upon import - by a factor of 30.

I'll try the things you have suggested and do a few rescaling tests with modo before export.

Thanks again for you response,
Matt.

[fallingbrickwork]

SOLVED.

Upping the scale within the modeller before exporting has corrected the problem, and the collision meshes are now working correctly.

Regards,
Matt.

[strangelet]

*dances the dance of Solved*

[spin]

Just a thank you for the post which mentions that _MCDCX is a suffix, rather than a prefix as mentioned on UDN page (http://udn.epicgames.com/Three/Colli...llision_Models)

I hadn't worked with Uengine since 2.5 and had been slamming my head against the desk as to why it no longer worked as I recalled, or indeed, as documented.