Tank Treads (alternate method?)

I am helping to create a game with a friend in Ogre 3D. I am charged with creating the models for the game, which includes tanks with working treads. I have no problem doing any of this in Blender using the popular method of an arrayed mesh around a bezier circle. However, I realize now that when exported for Ogre, the export does not recognize the bezier circle, and the treads come out as that one arrayed mesh, just without it curved to the shape bezier circle. I can make the arrayed mesh into a solid mesh, and it will stay that same shape regardless of the bezier circle, but then it will no longer follow the bezier circle path. Instead it will move around as a whole.

I was wondering if there is an alternate method anyone knows of to create some animated treads without using the bezier circle technique. I do know of using texture animations, but the tanks I am creating are high poly (http://www.youtube.com/watch?v=tueq8ITmPoo) so the treads will not make much sense being animated only through textures.

If you have an alternate method of animating treads, or have had a successful blender-to-ogre treads-creating method, please post it here.

This should probably be in the animation support forum.
I don’t know any ogres, I just use my blender!
My friend Roubal’s technique should do you up nicely.
Just animate the first tread and have the others follow. I think a chain of dependencies should work fine even in a game engine.

I recently tried this method, but I cannot fully figure it out. First of all, when I go to parent that many objects, blender seems to like to crash on me every time. Regardless of this, through saving repeatedly, I came up with what I thought was a finished product, but when I went to move it, it bunched up into a ball and I could move all the objects around as a single mesh, nothing more.

I’ve been using blender for 2 weeks, so instructions more detailed than 4 steps would be nice.

Well like I said I can’t help with game logic, but I can help with how to animate in Blender. One easy way to do this is make a cube (or individual tread) and just animate it moving the way you want around the track with an ipo curve. Then just duplicate the object and adjust the time offset (object buttons, anim settings). each duplicate just offset it by a little more.


treads.blend (256 KB)

Yes, this was the backup plan, thanks. I might try to do some creative shape animation because I’ve been meaning to learn it. It’s really not anyones fault but Ogres. I advise everyone now, if they are planning to export for Ogre3D, bezier circles are useless! So are arrays!

Time to do it the good old stop-animation way :stuck_out_tongue:

3dementia are you also using any alpha of 2.5? Because time offset works in 2.49 but in 2.5 it creates new ipo curve in window but actually doesn’t change time of object in timeline like it was in 2.49. And your blend file crashes blender 2.5 every time I try to open it :stuck_out_tongue:

Yes I should update my signature to reflect this, I use 2.49. I work for a small studio, and we will not upgrade until 2.5 is proven bug free, and some of our current projects are finished.

I know the problem in my way is that Ogre does not recognize the bezier circle upon export, and whatever object is animated using this bezier circles path ends up simply traveling straight on a single axis, as if the bezier circle never existed.

Is there a way to set a mesh to follow a bezier circle, then to convert it somehow so it still retains the path of of that bezier circle without having to keep the bezier circle? This would solve my problem, which is currently stonewalling me. I am limited to bone animation. Texture animation or shape animation isn’t going to work.

Still looking for a solution.

have you been here? What is the issue? I have presented you with 3 different solutions. In your last post you said the only animation that carries through is bone animation. If that is true, you will have to parent the treads to bones, and animate the appropriately. From my research into your problem, it seems the texture animation is the way to go for a game. And if there really is no way to animate a texture in ogre, it is a pretty useless piece of software.

Yes yes, I know you have presented me with 3 ‘solutions’. The problem is that I have found about 10 different ‘solutions’ that all fail on my own. Ogre is actually pretty powerful. I’m starting to actually have doubts on Blender. I just now found out my problem isn’t Ogre, it’s Blender. No matter what I do, Blender’s constraints do not get exported when going into .mesh (ogre) or .mdl (gamestudio). They do get exported into 3ds, fbx, and x, but then the mesh no longer follows the path. It’ merely retains its shape after being applied to it. I was simply looking for a few alternate methods of making treads, a few of which I got (thank you), and only 1 of which may actually work, yet I have reproduced what I thought to be exactly what the steps (which were vague) described, and it didn’t work. I asked for help on that to no avail so now fluent with Blender, even though it appears not be able to do the job of simply exporting a path constraint, I remain with it for its functionality sake. I can say that is the saving grace which keeps me from uninstalling it. It is nice software otherwise.

I guess I will be exporting into 3ds, getting 3dsmax, and making and exporting the constraints in there instead. As I said before texture animation just isn’t an option for the models I am doing. Maybe if they were low poly… Anyway thanks for your time.