Collision Mesh

[TheUnknownChemist]

I am having some trouble understanding (and implementing) the finer points of collision mesh.

I have created a sword and can’t seem to get the physics right, the main problems include:

Blade has no collision it seems, so when dropped it spins round and round through floors and walls and is very hard to pick up again.

Initially it is hard to pick up from where it is resting only when you hover over the cross guard does the hand icon appear.

Also when I add the scabbard from the steel long sword, and then export the new sword with scab and collision. I place it in game but when you draw the sword the scabbard is still attached to the sword and not at my side where it should stay upon drawing your weapon.

I would like to know also what is the best way for collision to be implemented, would it be using blender and nifskope or can you just use one program to set it all, and what is the best way for a sword collision to be done.

The only time I got a working collision mesh was using an existing one from OB’s steel long sword (as I didn’t need to edit a thing)

So you might be better able to help I will list what I do to create the collision quickly.

I start off with adding a cube mesh. I click f7 set draw type to bounds draw extra to cylinder I rename the OB and ME to cylinder.

I then rotate the X axis to 90, and resize the mesh be pressing S (all of this in object view) I resize it so the width of the collision is a bit larger than the sword itself. Then clicking the size manipulator button I stretch it so its length cover the blade. The n I click f4 click actor, set it to rigid body set mass to 25, radius to 1 or 2 (tried both along with higher and lower numbers all with varying effects all seem to be bad) then click bounds add property change from float to string then in the box I put HavokMaterial and HAV_MAT_METAL.

I do the same thing for the cross guard except rotate the z axis instead.

Once done ctrl+a on the new collision mesh and scale to OBdata no rotation as it makes my collision a big coin shape.

In nifskope I open up the first BhkCollisionObject and alter only the mass to be 25 and the second BhkCollisionObject that appears a little further down the list under a NINode (I guess the cross guard) and change mass to 25 as well. All done I save and load into the game this however does not work in game as stated above the problems start.

I hope that someone can see what I am doing wrong and help me figure this out, right now collision mesh is the only thing stopping me knowing all the basics of creating new weapons and static objects for OB

Thanks in advance

[Artisanix]

The n I click f4 click actor, set it to rigid body set mass to 25, radius to 1 or 2

Collision for weapons is not of rigid body type, you should leave that setting at its default no collision state.

[TheUnknownChemist]

Collision for weapons is not of rigid body type, you should leave that setting at its default no collision state.

Okay will give it a try hopefully that is the only thing that is effecting the collision, I notice the official oblivion mesh's have more than one property added and thought maybe that might contribute to the problem.

Thanks will post how it went

[WindmillTilter]

For the scabbard to stay at your side, the NiTriStrips must be inside a NiNode named Scb, and you need a NiStringExtraData with SideWeapon. By far the easiest way is to replace the sword and scabbard NiTriStrips in an exsting mesh with your own. Same applies for havok, it's quite unusual to export havok for weapons. If you keep the existing havok in a vanila mesh it only takes a few seconds to alter it's dimensions to suit your sword.

Gook luck, if you have any more troubles just post the specifics of where your stuck.

WT

[TheUnknownChemist]

Okay I made a new collision mesh didn't add the rigid body and added properties in f4 menu to match a steel longswords exactly. Then did not change the nif at all, the scabbard works fine. But now the sword just launches itself into the air if I enter the cell it's in (I found this out after turning collision off picking it up dropping it and watch it fly) The main problem it seems is the rolling and bouncing of the object and the lack of collision round the blade.

Out of curiosity I thought why not try a bethesda collision and although it works okayish it still rolls around on it's side. like a can (not at the crossgaurd like mine does)

To be honest I think I have completely misunderstood how to go about making the collisions for a sword. The steps in blender and nifskope that need to be taken ect. any one that might be able to guide me through this (like a step by step of how you might make collision for a sword or any good online tutorial (tried most of the cs wiki ones but to no avail)

Thanks all

I think it is important to note I have little to no idea how to use nifskope except how to add the texture dds files to it. although fairly okay at blender

[TheUnknownChemist]

Sorted seems my export options where slightly off, as was inertia settings in nifskope. It all works fine although still not 100% on how or why enough playing with what I got working will be more than enough reference.

Thanks all