Problem with Animation Blend mask, Attached Objects and LOD

[BradJ]

I have encountered some issues using LOD, with attached objects and with animation blend masks. I am adding a bag to the hand of a character and overriding the arms animation to one that is a carry animation, instead of whatever the rest of the body is doing.

Just want to confirm that what I am doing is correct.

First I attach the bag to the characters hand bone

Code: Select all

  entity->attachObjectToBone( m_AttachBoneName, m_Bag, rotation, m_Offset );

Then I set the blend mode for the skeleton to Cumulative, as I am using a percentage for the animation blending; and zero for any part not affected by the animation. The first problem I found was I need to manually set the blend mode for all lod levels.

Code: Select all

  entity->getSkeleton()->setBlendMode( Ogre::ANIMBLEND_CUMULATIVE );
  size_t count = entity->getNumManualLodLevels();
  for ( size_t i = 0; i < count; ++i )
  {
	entity->getManualLodLevel( i )->getSkeleton()->setBlendMode( Ogre::ANIMBLEND_CUMULATIVE );
  }

Then I found that Ogre doesn't copy the blend mask data between LOD levels, so I added code to do so.

Code: Select all

  //---------------------------------------------------------------------
  void AnimationState::copyStateFrom(const AnimationState& animState)
  {
       // the new code to copy the blend mask data
       if ( !mBlendMask && animState.hasBlendMask() )
   	   _setBlendMask( animState.mBlendMask );
	    else if ( mBlendMask )
		{
			if ( animState.hasBlendMask() )
				_setBlendMaskData( &(*animState.mBlendMask)[0] );
			else
				destroyBlendMask();
		}
        mTimePos = animState.mTimePos;
        mLength = animState.mLength;
        mWeight = animState.mWeight;
        mEnabled = animState.mEnabled;
        mLoop = animState.mLoop;
	    mParent->_notifyDirty();
  }

Lastly I found that the bags position wasn't updated when LODing. So I have to manually update the animation for the base mesh to update the bags position.

Code: Select all

  int index = entity->getCurrentLodIndex() - 1;
  if ( index > -1 )
  {
      entity->_updateAnimation();
  }

Can anyone confirm that these are oversights / bugs in Ogre or am I going about this the wrong way?

[so0os]

Ogre should do that IMO. Since you posted the code, a papercut would do.

[dark_sylinc]

Are you using manual Lods or automatically generated ones?

[BradJ]

I am using manual LODs.

[dark_sylinc]

Oh, it's a known issue with manual LODs (unfortunately an old one). It has nothing to do with the fact you're using blend masks.

Basically, because each LOD may be using a different skeleton, each one has it's own instance. Therefore when you switch LODs, you switch the skeleton instance; which may not be at the same animation position.

This doesn't happen with automatic LODs.

See this post.

[mySunSet]

I make frequent use of this one http://www.ogre3d.org/docs/manual/manual_71.html