🔒 Locked

OpenAL and Irrlicht

Started by Amarth Apr 24, 2006 at 12:46 PM 6 replies 6.5k views

Original Post

Apr 24, 2006 at 12:46 PM

I have this tiny problem with a testing program implementing Irrlicht and OpenAL.

void updateListener(ICameraSceneNode* cam){
	ALfloat pos[3];
	ALfloat ori[6];
	pos[0] = cam->getPosition().X;
	pos[1] = cam->getPosition().Y;
	pos[2] = cam->getPosition().Z;

	ori[0] = cam->getTarget().X;
	ori[1] = cam->getTarget().Y;
	ori[2] = cam->getTarget().Z;
	ori[3] = cam->getUpVector().X;
	ori[4] = cam->getUpVector().Y;
	ori[5] = cam->getUpVector().Z;
	alListenerfv(AL_POSITION,pos);
	alListenerfv(AL_ORIENTATION,ori);
}

I know I could condense this a bit without the arrays, doesn't matter. The problem is that sound seems reversed, left and right are switched. I use this in a tiny program where I load a TestSceneNode and travel around with a CameraNodeFPS. There's nothing special... Initialisation is done with ALUT, everything seems to be alright. It *could* of course be that the device driver is wrong, or that my stereo system is just set up wrong, but I higly doubt it. I can post the full source to the program is that is any more helpful. It ain't that much bigger, but I don't think it's important. Most other variables are left at defaults. Any views on this? Thanks!

owiley

Apr 24, 2006 at 1:39 PM

maybe its that openal uses different coor

Amarth

Apr 24, 2006 at 2:13 PM

What the...

You're right.

I didn't quite expect Irrlicht to have a left-handed coordinate system.

Anyway, now for a solution...

[EDIT] Am I right in that I only need to change one sign of my lookat vector?

void updateListener(ICameraSceneNode* cam){	ALfloat pos[3];	ALfloat ori[6];	pos[0] = cam->getPosition().X;	pos[1] = cam->getPosition().Y;	pos[2] = cam->getPosition().Z;	ori[0] = cam->getTarget().X;	ori[1] = cam->getTarget().Y;	ori[2] = cam->-getTarget().Z;  //LHS to RHS	ori[3] = cam->getUpVector().X;	ori[4] = cam->getUpVector().Y;	ori[5] = cam->getUpVector().Z;	alListenerfv(AL_POSITION,pos);	alListenerfv(AL_ORIENTATION,ori);}

[Edited by - Amarth on April 24, 2006 2:13:49 PM]

owiley

Apr 24, 2006 at 11:03 PM

I think that should work did you take a look at the openal wrapper on the wiki site? my bad thats from site ogre. I'll see if i can code it up for you some time tommor im busy with work right now

Amarth

Apr 25, 2006 at 3:46 AM

I think the solution has to be to flip *all* the Z signs.

However, this doesn't solve it. It feels as if listener orientation doesn't change a thing... If I turn around, nothing changes, while the sound should be in the 'other ear'.

Amarth

Apr 25, 2006 at 9:39 AM

Finally solved it. getTarget() does not return the direction vector, but the actual target.

void updateListener(ICameraSceneNode* cam){	ALfloat pos[3];	ALfloat ori[6];	pos[0] = cam->getPosition().X;	pos[1] = cam->getPosition().Y;	pos[2] = -cam->getPosition().Z;	ori[0] = cam->getTarget().X - cam->getPosition().X;	ori[1] = cam->getTarget().Y - cam->getPosition().Y;	ori[2] = -(cam->getTarget().Z - cam->getPosition().Z);	ori[3] = cam->getUpVector().X;	ori[4] = cam->getUpVector().Y;	ori[5] = -cam->getUpVector().Z;	alListenerfv(AL_POSITION,pos);	alListenerfv(AL_ORIENTATION,ori);}

Hope this helps someone else.

kburkhart84

Aug 31, 2006 at 1:29 PM

I use Irrlicht myself. I used to use it with OpenGL, which uses the same coordinate system as OpenAL, which I also used for a time. I got to liking DirectX's sound stuff a little better and since I only use windows, it works for me. I switched to Irrlicht to learn that positive Z is now in front instead of behind like in OpenAL/GL. It wasn't hard to switch, but yeah, using OpenAL for sound with it adds in a little bit of complication but for the most part, just switching the Z axis around should do the trick, but you have to do it for everything, not just sound positions.

Topic Locked

This topic has been locked by a moderator. New replies are not allowed.