collide<error>????

Scripting Issues
1

This is the error message I got when I ran my code. I just want to make a simple collision detection via Panda’s collision traverser. I defined my collision solid in MAYA, then add tags to those parts. The following is the part of my code, which is based on the CollisionDetection sample:

    # Load the box and place it in the scene, also loads its wall and ground
    # collision solid
    self.box = loader.loadModel("Models/Box")
    self.box.reparentTo(render)
    # The wall
    self.walls = self.box.find("**/wall_Coll")
    self.walls.node().setIntoCollideMask(BitMask32.bit(0))
    self.walls.show()
    # The ground
    self.boxGround = self.box.find("**/ground_Coll")
    self.boxGround.node().setIntoCollideMask(BitMask32.bit(1))
    self.boxGround.show()
    
    # Load the car and its collision solid      
    self.carRoot = render.attachNewNode("carRoot")
    self.car = loader.loadModel("Models/Car")
    self.car.reparentTo(self.carRoot)
    # Car collision solid
    self.car_coll = self.car.find("**/Car_Coll")
    self.car_coll.node().setFromCollideMask(BitMask32.bit(0))
    self.car_coll.node().setIntoCollideMask(BitMask32.allOff())
    self.car_coll.show()
    
    self.cTrav = CollisionTraverser()
    self.cHandler = CollisionHandlerQueue()
    ase.cTrav = self.cTrav
      
    taskMgr.add(self.watcher, "watcher")
    
    def watcher(self, task):
        dt = globalClock.getDt()
        for i in range(self.cHandler.getNumEntries()):
            entry = self.cHandler.getEntry(i)
            print "ENTRY: ", entry
            name = entry.getIntoNode().getName()
            if   name == "wall_Coll":   self.wallCollideHandler(entry)

However, when I drive the car into the wall, it doesn’t print any entry information in the console. It means that the traverser does not detect any collision. But how does the error come about?
Any suggestion will be appreciated! Thanks!

2

Right. You probably cannot collide a collisionpolygon into another object. That feature is not yet implemented in Panda3D, I’m afraid. Use another type of collisionsolid.

Probably drwr knows more about this.

3

Do you mean that if I use other kind of collision solid, like sphere or something else, it will work?

4

Yes, it will probably work.

If you want a tube-like shape, you can set the setScale of the NodePath of the solid to stretch it over the y-axis.

5

Hello Aq_La,
I have never set up models yet (adding the selection set tags (such as for “collision” tags etc). Is this a fairly simple operation to do? Is it built in with a maya exporter or is this something you have to do by hand later in the .egg file?

Thanks, hope this question makes sense…let me know if it doesnt.

6

Yes, you have to add " ObjectName {…}" such kind of tag into the egg file by hand. The method is explained clearly in the Collision Detection sample. and I suggest you to open the egg file, it’ll make sense.