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Simple blender to pod problem

(5 posts) (3 voices)

Started 3 months ago by duncan
Latest reply from burnt-almonds

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duncan
Member

Hi,

Something that I've been working round, but now I would like to resolve is when I export an object from blender to a pod then into cocos3d I have -90 on the x rotation axis.

If I simply open up blender and export my file as a dae and then run the ColladaToPOd (2.09) version on my file with the settings set out at

http://brenwill.com/2011/cocos3d-importing-converting-collada-to-pod/

When i do the following

CC3MeshNode* cube = (CC3MeshNode*)[self getNodeNamed: @"Cube"];
CC3Vector testRot = cube.rotation;

testRot.x is always -90 even though in blender it is 0

I've tested loading the pods from 3D Mashup and these have x set to -0.

Any ideas?

I'm obviously just missing something very basic.

Thanks in advance
an ashamed Duncan.

Posted 3 months ago #
Bill Hollings
Moderator

@duncan

It might have something to do with the fact that the Collada2POD converter swaps the Y and Z axes during conversion (I don't know why).

Have a look at the Coordinate Systems section of the document you mentioned for more info and suggestions for how to compensate.

...Bill

Posted 3 months ago #
duncan
Member

Yes, I'm going to try simply rotating the cube by +90 on the x axis in blender.
Is this what you have done with your models?

Thanks
Duncan.

Posted 3 months ago #
burnt-almonds
Member

I'm actually seeing the same exact issue that duncan described. I followed your instructions, Bill, on exporting a model from blender and converting it to pod via collada2pod. Based on those instructions, what I'd expected to see (perhaps wrongly interpreted) was that the model vertices would be rotated -90 degrees around the X-axis. What I'm actually seeing is that the vertices in the actual CC3PODMesh seem unchanged from what they are in blender (ie. still Z-up orientation), but the CC3PODMeshNode has a rotation of cc3v(-90, 0, 0). The reason I noticed this is that I'm reading the vertex data out of the mesh and importing it into bullet as a btTriangleIndexVertexArray. Not a big deal, I can account for that rotation, but In wondered why it was there and whether maybe something had changed. I'm also using version 2.09 of collada2pod.

BTW, this is my first post here and I wanted to say thanks for making cocos3d available. It's a really great toolkit.

-ba

Posted 3 months ago #
burnt-almonds
Member

Update -- I was able to get things working by changing the Coordinate System in Collada2POD from Model Space to World Space. Collada2POD then writes out the mesh with Z rotated to Y and when its loaded by cocos3d the node.rotation is 0, 0, 0.

Posted 3 months ago #

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