Cana anyone explain me the Metaselector

m3rk · Post by **m3rk** » Tue Dec 09, 2008 2:49 am

How can I set the z axis? Does vector3df goes like this vector3df(x,z,y);?
Because when I try to set the middle to 1000, I started from the top so that's why I think the middle is z. Can anyone explain it?

camera->setPosition(core::vector3df(-100,0,-150));

By the way, check out the image below. They are all floating. How can I fix this? I try to make it 0 but it didn't work.

nathanf534 · Post by **nathanf534** » Tue Dec 09, 2008 2:58 am

a vector is (x,y,z) in irrlicht.
the snowmen arn't touching the ground, probably because the floor isn't level with the axis. Try setting the position of the snowmen to something like (0,-10,0) or you could enable collision detection, and turn on gravity.

Halifax · Post by **Halifax** » Tue Dec 09, 2008 3:27 am

I don't know about the whole vector3df(x,z,y) because I define it as vector3df(x,y,z), so in my opinion, the best thing would be to define it as: vector3df(horizontal,vertical,depth).

m3rk · Post by **m3rk** » Tue Dec 09, 2008 3:49 am

Now I'm confused. Where to define it?

And do I need to put scene::ITriangleSelector* selector = 0; for each object I want to put gravity? Is there any simplest way to do this? Because I found this thread: http://irrlicht.sourceforge.net/phpBB2/ ... +collision

He use selector for camera and selector2,selector3,selector4 for the object. What will happen if I put hundreds of object?. So it means, selector100? LOL.

nathanf534 · Post by **nathanf534** » Tue Dec 09, 2008 4:09 am

you can put all of your selectors into one by using MetaSelector.

Dark_Kilauea · Post by **Dark_Kilauea** » Tue Dec 09, 2008 5:49 am

Irrlicht uses the Y axis for height, so that may be what is confusing you.

+X is to the left.
+Y is upwards.
+Z is out of the screen.

hybrid · Post by **hybrid** » Tue Dec 09, 2008 8:49 am

Dark_Kilauea wrote:Irrlicht uses the Y axis for height, so that may be what is confusing you.

+X is to the left.
+Y is upwards.
+Z is out of the screen.

Now that is confusing

Irrlicht uses a left-handed y-up coordinate system, which means
+x to the right, +y upwards, +z into the screen

rogerborg · Post by **rogerborg** » Tue Dec 09, 2008 12:04 pm

Indeed. Hold your left hand out in front on you, with your thumb pointing up at the ceiling, your index finger pointing at the screen, and your middle finger pointing to the right.

Middle finger = +X
Thumb = +Y
Index finger = +Z

It's that easy to remember. Write the letters on your fingers if it helps.

Dark_Kilauea · Post by **Dark_Kilauea** » Tue Dec 09, 2008 11:02 pm

Ah yes. Poor me has been using right handed coordinate systems too much lately. So easy to get confused.

rogerborg · Post by **rogerborg** » Tue Dec 09, 2008 11:07 pm

Not really. Do the left hand point, and all is well with the world. Do the right hand point at your own face and you break your wrist and/or lose an eye. And that's the best case scenario.

m3rk · Post by **m3rk** » Wed Dec 10, 2008 10:18 am

Ok now I got it. Now I have a problem with metaSelector. Can anyone give me some code that uses metaselector and I'll try to understand it.

hybrid · Post by **hybrid** » Wed Dec 10, 2008 10:52 am

Example 15 from 1.5 beta.