[SOLVED]Terrain collision vs geometry dynamicmesh collision causes a… Black hole?

Troubleshooting physics
#1

Hey forum, been having fun with this jMonkey business, I’ve been messing around with physics now, obviously my player model works fine with the terrain, however when I spawn a cube, as soon as it collides with the terrain, it does some weird shiz, thanks in advance for your insight, here’s a video:



http://www.youtube.com/watch?v=fGea57FY0zw



and some code:



[java]public void Initialize_Model() {

b = new Box(location.clone().addLocal(direction.clone().multLocal(10f)),1,1,1);

geometry = new Geometry(“Box”,b);

Material mat = new Material(instance.am,“Common/MatDefs/Misc/Unshaded.j3md”);

mat.setColor(“Color”, ColorRGBA.Red);

geometry.setMaterial(mat);

CollisionShape cs = CollisionShapeFactory.createDynamicMeshShape(geometry);

rbc = new RigidBodyControl(cs,10);



instance.getBulletAppState().getPhysicsSpace().add(rbc);

geometry.addControl(rbc);



instance.rn.attachChild(geometry);

}[/java]



PS: I’ve tried searching but couldn’t find the problem



PPS: The terrain:



[java]

terrain = new TerrainQuad(“my terrain”, patchSize,1025,heightmap.getHeightMap());

terrain.setMaterial(mat_terrain);

terrain.setLocalTranslation(0,-100,0);

terrain.setLocalScale(1,0.5f,1);





CollisionShape cs = CollisionShapeFactory.createMeshShape((Node)terrain);

RigidBodyControl landscape = new RigidBodyControl(cs,0);

terrain.addControl(landscape);





instance.getBulletAppState().getPhysicsSpace().add(landscape);

group.attachChild(terrain);

instance.rn.attachChild(group);[/java]

#2

How do you create the collision shape for the terrain? How does the physics debug view look? (physicsSpace.enableDebug(assetManager))

#3

Hey, I added terrain code as an edit (well the bit which I thought mattered anyways).



When I enabled debug, I can perfectly see the blue mesh around the cube



EDIT: However no mesh around the terrain.

#4

Try not casting the terrain to a node.

#5

Didn’t work unfortunately.



Here’s something though, when I give it a shot of force at the start (so it’s moving faster than usual) this is how it behaves, weird huh?

http://www.youtube.com/watch?v=BT4yTGLpXJs



In the meantime, I’m going to continue looking around my code :slight_smile:





EDIT: Instead of terrain, I spawned a huge plane, it does the exact same thing with the cubes.



EDIT #2: This cube spawning stuff has been in a seperate class, I’ve spawned a cube with ridibody in the main class and it works 100%, I’m gonna try take it from here and if I find the answer I’ll tag as solved and explain incase anyone hits it.

#6

Solved, SOLUTION:





problem was here:

[java]b = new Box(location.clone().addLocal(direction.clone().multLocal(10f)),1,1,1);[/java]



I thought you were meant to enter the location where you wanted your box to start on the first parameter, this was causing the problem. Instead I spawned the box with Vector3f.ZERO and later, with the geometry I setLocalTranslation to the position I wanted for the box.



:slight_smile:





[java]b = new Box(Vector3f.ZERO,1,1,1);

geometry = new Geometry("Box",b);

geometry.setLocalTranslation(location.clone().addLocal(direction.clone().multLocal(10f)));[/java]

#7

Yeah, you are pushing your center of mass out of the box this way.

#8

Cool effect, though ^^

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