View Full Version : Which way is up?

07-24-2013, 01:17 PM
So bunkspeed is Y up, right? But if you take a planar map and choose Planar Y it's not actually the Y plane. The Z plane is the Y plane.
So for world space you're using Y up, but for texture mapping you're using Z up?

Don't you think that's a little confusing?

I've actually always disagreed with Y up for anything other than screen space (the camera's viewpoint). And since 99% of the people using bunkspeed are from manufacturing and design, wouldn't Z up make more sense anyway?

I'm just curious what the thinking on that is.

07-24-2013, 01:43 PM
Z up fan here too!!!!!! :D

07-24-2013, 04:54 PM
Well Z depth makes sense when looking through a camera. But since the world isn't liked to cameras, since multiple cameras are able to exist at once, then it makes sense for the world to have an independent coordinate system. If you only have two dimensions which are considered as XY on a graph, then it makes sense that plane would be from a top view and a third axis would add the depth necessary for a 3rd dimension. Realistically you can build things in 3d space in any coordinates you want. But since people generally build things Up, it would make sense for a 3D world to exist as XYZ and not XZY or ZXY. Since the camera moves around, it's XYZ is always changing, so it must only correlate to the world space, not have the same system.

I don't really care Too much, although I would say that most likely most of this community uses Z up in the cad software. But it would be nice if the software itself was consistent. World is Y up, but texturing is Z up? That's the part I really take issue with.

08-05-2013, 10:17 PM
Thanks for the comment, Andy. Noted on the axis differences. I will look into why our texture maps use Z up. For more direct answers, I'll refer to Dave's infinite knowledge on this topic...

08-12-2013, 09:52 PM
Just to jump on the band wagon for a minute it does get annoying working between multiple applications and there seems to be NO standard X,Y,Z coordinates from platform to platform..

08-13-2013, 11:21 AM
I'm aware of that, and I have to convert all of the time. But I've never seen an application that doesn't keep to one decision. Bunkspeed is Z up sometimes, and Y up sometimes? That doesn't make a whole lot of sense. Just pick one. It makes it slightly more predictable. And since undo only works on half of the things you do in Bunkspeed it's kind of nice to not have to save before every single thing you do. I like to know that changing a number in Y is going to move it in Y.

08-15-2013, 07:22 PM
@Andy, appreciated and noted. I will bring this up with my upcoming meeting with our developers. is there any way you could please send me a screenshot(s) of your headache/issues to better diagnose? brian.hillner@bunkspeed.com

Thanks Andy.

08-19-2013, 01:43 PM
The fact we use Y up was a legacy decision made before my time for a reason i can't explain. I think it had something to do with our very first demo product only being able to pull in Maya data therefore a decision was made to synchronize our coordinate system with maya's.

with that said, the reason the texture coordinates when using mapping is out of sync with the world coordinate system is because the texture mapping is based on the original axis of the model/part itself. So, in other words, when you have model that you bring in that started in a Z up application, you tell us this on import and your model is then rotated accordingly to look correct in our Y up world. Once you decide to texture map a part, the mapping still acts as if the model is in a Z up world.

This has been a low level inconsistency that has been on our list to attend to for a while now. The good news is that we are inching closer to having the focus to look into this and other inconsistencies on this level.

i think with this one, knowing is half the battle so now that you know this, it may help it be less annoying.

08-19-2013, 01:46 PM
It actually does make it less annoying because it seems like less of an oversight. When you crash literally every time you use a software at least once, things like this seem more like unattended bugs.

08-19-2013, 01:53 PM
I think you should take a poll on who else experiences crashes "literally ever time they use our software". I think you'll find that at this stage, we need to start reviewing your expectations/usage/hardware because quite frankly, i don't know anyone else that this either actually happens to or refers to it being an issue so frequently. We'll take this offline once you've had a change to settle into 2014 a bit. Do you find any overlap with iray crashes you experience in Max when using identical data or similar workflows?