hi egon,

I'm not so familiar with matrix transformation, but I did try using obj export method in Blender's source code (global matrix * object rotation matrix), where global matrix is the destination matrix which represent JPCT coordinate system and object rotation matrix obtained from Blender API. Yet, no luck on that. I wonder if you can show few guidance on the matrix tranformation, perhaps the one you mentioned, mirror transformation, or other keyword to look for in google.   

hi egon,

I realized the coordinate system I mentioned from Blender is incorrect, it should be like this:
+Z is up
+X is right
+Y is forward

with translation vector at column 3 (which i believe column major matrix)

Apology for the mistake.

I did try with your methods, and the model rotation doesn't seem to be correct. I checked and Blender is using right hand coordinate system, and I'm guessing JPCT is using left hand coordinate system? CMIIW, converting right hand system to left hand system cannot be done by only rotation, right?

Strangely, I tried negating final position y and z in shader (which i think it's same with rotateX) and it works ok now. I wonder if I missed somewhere in software part.

Hi raft and egon,

Sorry for bringing this up. Previously I have implemented hardware skinning and was having initial rotation issue, in which the object appears different rotation than the one original with software skinning. The incorrect rotation started to cause issue when JPCT detects clipping boundary and object is not in the screen and it's automatically not showing the object, but in actual it should show as it's just having different rotation after processing in shader, which is after clipping process.

I was just wondering if there's any addition rotations applied before vertex is passed to shader. I'm afraid I might have missed some rotation matrices, or it could be something else that cause the issue. Thanks.

why do you want to rotate the skeleton?

The reason I would need to rotate the skeleton is because of the exporter exports 3D object in different coordinate system. Therefore, there's a need to convert exported coordinate system to JPCT's as been raised in this post http://www.jpct.net/forum2/index.php/topic,2524.msg18503.html#msg18503

I actually tried getRoot().rotateXX() and it worked! I tot it would be the same with Animated3D.rotateXX() in which the pivot point is reset. It seems ok now, but still need to double confirm if all objects behave the same too.

Thanks alot~

Ok sure. Thanks egon.

Hi egon,

I saw the Camera.transform() is creating new SimpleVector object for every use. Can we have another method to pass our own object for the result?

My bad.. The initial light position is negated at the beginning. Im using Blender to convert the light and other 3D object position into OBJ model and grab the position from there, so I dun have to rotate the mesh again. And the mapping is -Y for Y up and -Z for Z forward in Blender. But is it the correct way if we negate first and camera.tranform in this case? I tried just tranform w/o negating it, but the result seems incorrect.