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GuanoLad
10-25-2009, 07:00 PM
This may sound like a stupid question, but I have been using Lightwave for years and this still confuses me.

When I open up Modeller, and start creating, I have no idea which way around the views are facing. I assume that +Z is meant to be the front of my model, yet the Perspective view default always shows the back of it. And when I load it into Layout, the camera is also looking at its back.

This is important to know because when animating the model using the Motion option of Orient to Path, the forward direction has to be right.

Why would objects facing forward be faced away from the camera? What is the rationale behind this?

And can I set up my viewports so they are oriented in a more logical fashion when I begin?

AdamAvenali
10-25-2009, 07:32 PM
yeah i have found that odd as well, but i noticed i naturally model my characters facing -Z for some reason, so it just works out for me.

probiner
10-25-2009, 08:09 PM
You can set your Z viewport so the model faces you (front) but then you''ll have to change Right to Left and Top to Bottom so that the viewports line up properlly.
I think this happens because 3D apps views were thought like the american way of opening the projections cube. I like more the european way, but there no way to acomplish it in the applications since they line up the info acording to the american way.

Cheers

GuanoLad
10-25-2009, 08:27 PM
Ah, that may be it.

I think I learned the same way as you, probiner, down here in the Antipodes (New Zealand/Australia). I'm looking at it like it's within a cube, and they are probably thinking in terms of unfolding the cube, so they face outwards and away.

I have reoriented the viewports, but the perspective view can't change except by hand.

Jockomo
10-25-2009, 09:05 PM
Here is the reasoning behind why the viewport is the way it is.
When you model a character, If I say raise the right hand... if it is facing the +Z then the hand on the right side of the character is raised.

If you model the character facing the -z then all of that stuff is backwards and can get confusing.

probiner
10-25-2009, 09:23 PM
Maybe i'm wrong but from what i remember is something like this.

http://i153.photobucket.com/albums/s202/animatics/Lightwave/projections_2.png

So European way for me is way more natural cause the cube is opened from inside.
So if you have an object over a sheet of paper you just roll the object over the sheet and you have the projections. The american way would be like rolling the object behind the paper.

You can't setup the european style in a system that lines up like the american one. Shame =\

Cheers

GuanoLad
10-26-2009, 01:07 AM
If you model the character facing the -z then all of that stuff is backwards and can get confusing.I hope that's not really the reason, because that assumes a lowest common denominator that is unwarranted.

I would have thought anybody who can use 3D graphics software can orient things around in their head with ease.

Dodgy
10-26-2009, 01:49 AM
I always point objects facing towards the +Z axis, if only because the Target function uses the +Z direction as the direction it points along. So a car will face the right direction if it's got a Target set.

probiner
10-26-2009, 03:29 AM
What Dodgy said GuanoLad.

Belive me i tryed to make it more natural, but after you'll understand you're just looking for complications.

I wish 3D applications would let you choose wich style you want cause european is way more intuitive and natural i think. But since it's like this you better get used to.

Cheers

GuanoLad
10-26-2009, 06:03 PM
Yes, when Targets and Motion Paths started to be important to me, that's when I began to get confused by how it was set out.

A little bit frustrating, but nothing to get excited about, I suppose.

toby
10-27-2009, 04:48 PM
There's a simpler way to understand this - cameras get animated too, so they face +Z for the same reason characters need to be, for the animation programming to work correctly. So if they're both facing the proper direction, the camera will be looking at the character's back when loaded into a default scene.

The view in Modeler is not a camera and doesn't get animated, so it's set up to look at what should be the front of your model.

GuanoLad
10-29-2009, 02:51 AM
Except it doesn't. Modeller's perspective view defaults to looking at the back of the model.

And even if that is the logic behind it, it hasn't been thought through very well.

Surrealist.
10-29-2009, 10:18 AM
The reason is because everything including the camera in Layout has to default to the same +Z orientation for targeting and other things. If for instance you had an arrow and the camera was behind it in a POV shot parented to the arrow as it flies through the air toward the target, both the camera and the arrow would likely have some kind of targeting or "align to" activated. So with "align to" the arrow will face toward the positive direction of the path even if the path itself is not facing in the Z direction, the positive direction of the path will determine where the arrow is facing and it will take the object orientation data as the reference for the targeting. Whatever is facing in the +Z will point toward the target.

Since the camera also will likely be targeted you will have consistency. This is why the camera defaults to pointing down the Z direction. To keep all things consistant, the persperctive view in modeler also defaults to this orientation.

It is not intuitive when you are modeling, it only makes sense once you start animating and for this reason there is nothing stopping you from simply modeling it backwards and then flip it for the final version. That is what I ususally do.

Tom Wood
10-29-2009, 02:44 PM
I asked this question years ago and I think the answer then was that it had always been that way. :D

The next best answer was that it had to be that way because of the way inverse kinematics work.

probiner
10-29-2009, 03:22 PM
It's like you said Surrealist, it makes sense for animation. Very few for modeling (wich is GuanoLad concern i think).

If you want to draw the projections of a cuboid in a paper is rather simple roll it over the paper and as it rolls you get the projections.
American projection method it's like picking the object and make a decal or transfer to the the paper as you roll it (so what you have to draw is facing the paper and not you). But if you put the face you want to draw/model facing you, the roll gets unatural like in the image above.

So European method might be more natural: As you roll the object you get the projections and you see the face you want to draw/model

http://www.newtek.com/forums/attachment.php?attachmentid=78829&stc=1&d=1256852104

I -guess- every software uses American method and no one is going to change that even as an option (wich would be cool).

So after trying, again, to make European fit American i came to this.
Though you are seeing the Bottom of your model it's quite easy to forget that at treat it has top. Altough the Front/"Top" alignment is ok the orientation is not, but i think mentally it might work. Especially because now you have Front =)
You guys see any issues with this?

http://i153.photobucket.com/albums/s202/animatics/Lightwave/EuropeantoAmerican.png

Cheers

PS: Oh my bad, GuanoLad, is concerned about Layout -_-'

GuanoLad
10-29-2009, 10:24 PM
Well it's Modeller I'm more concerned about, because it's hard to see which way is up when you use wireframe view, so I'd make my model, thinking certain things were the front or the left side or whatever. Then I'd load it into Layout, and it would be facing the camera, which seemed to make sense - until I play with Targets and Orient-To-Path and it would be all in reverse.

So Modeller is the place where it's backwards, for me. I long ago played around with the Viewport options to get a more logical default setting, but as it still didn't make sense to me, I decided to ask the question.

However, I accept Surrealist's answer does make sense.

CC Rider
10-30-2009, 06:53 AM
I think to put it more simply, think of the modeller environment like a stage...where you are seated in the audience.
The audience is actually facing the back of the stage, but the actors/props are facing the audience or camera.

probiner
10-30-2009, 07:10 AM
I think to put it more simply,
To be honest i made a mess out of this :S (with wrong concepts and all)

But GuanoLad seems content :P

But yeah, theres a lot of concecpts in 3D that you try to understand and many times in the end you just suck it up, and go with whatever works.

Many of those things are those mental workarounds we deal everyday and in a point we just dont think about them, but all summed they might consume time.

Cheers