Global rotation of joints

[Linkin Puck]

You have bumped this topic 8 times. Are you trying to set a world record?

[B@z]

8 times? i think its more than that. but if some kind programmers would answer, and not bury this topic, then i wouldnt have to bump.

you know, even if you guys ignore this topic, the problem still appears. check the first time i asked for help. its april 13. and now its may 19, and still no answer. i just only get very helpful answers like ur post, but nothing usable (except scarabol, and arras)

i hate how ppl ask something, i answer, then they never return to this topic...

[Midnight]

I'm just amazed he modeled in the vagina and nobody has mentioned it yet lol

[B@z]

vaginas are very essential for projects

[MrJones]

I need this feature aswell.

Is there really nothing like setAbsoluteRotation()? It seems pretty much impossible to rotate a bone towards an absolute position independently from its parent's rotation.

Isn't there a way to do this?

[xDan]

just for the record, I had a go at this since I might want it sometime, but I gave up with a headache...

I got this, which, er, doesn't seem to work Well it did something in some circumstances, I forget what though.

Code: Select all

void SetAbsoluteRotation(scene::ISceneNode *node, core::vector3df absoluteRot)
{
	// Could perhaps recurse.
	if (node->getParent())
		node->getParent()->updateAbsolutePosition();

	node->updateAbsolutePosition();

	// Old absolute rotation
	core::quaternion qOldRotAbs( node->getAbsoluteTransformation().getRotationDegrees() * core::DEGTORAD );

	// Desired new absolute rotation
	core::quaternion qDesiredRotAbs( absoluteRot * core::DEGTORAD );

	// Delta
	core::quaternion qDelta;
	core::quaternion qOldRotAbsInv = qOldRotAbs;
	qOldRotAbsInv.makeInverse();
	qDelta = qOldRotAbsInv * qDesiredRotAbs;

	// Relative rotation
	core::quaternion qOldRelative(node->getRotation() * core::DEGTORAD);

	// Result!
	core::quaternion result = qOldRelative * qDelta;

	// Set
	core::vector3df euler;
	result.toEuler(euler);
	node->setRotation(euler * core::RADTODEG);
}

[MrJones]

This looks perfect - and it does not work? that's pretty sad, because it looks _exactly_ like the thing I actually wanted. Need to test this out...

If I had to do it myself I'd do it in a similar way (using quaternions). Sadly my maths are probably bad enough that I cannot even fix yours.

What about adding ->setAbsoluteRotation() to the engine core? It would be pretty useful e.g. for pistols or also if you want the head of a character to look at a specific thing.