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silviotoledo
07-31-2012, 09:37 PM
Why is this inverted in almost all 3D softwares?

Why is it inverted in Lightwave?

jeric_synergy
07-31-2012, 09:55 PM
Why is this inverted in almost all 3D softwares?

Why is it inverted in Lightwave?
Beats me. It's the same way in Blender.

You have to construct some convoluted justification in your own mind and stick with it. Since in LW "Back" corresponds to "the back of a vehicle", you can think "I'm looking at the back end."

mdharman
07-31-2012, 09:56 PM
Great question! Why?

metahumanity
07-31-2012, 09:58 PM
Why is this inverted in almost all 3D softwares?

Why is it inverted in Lightwave?

Itīs not inverted, you just expect it to be the other way around...for whatever reason.

JonW
07-31-2012, 10:14 PM
Because you look forward & not backwards!

mdharman
07-31-2012, 10:31 PM
Funny that it makes sense to someone from Australia. Isn't everything backward down under?

jeric_synergy
07-31-2012, 10:37 PM
Because you look forward & not backwards!
AS you're looking forwards, the label says "BACK". Naturally, that's confusing.

I think the devs are so jaded, errrr, EXPERIENCED, they've forgotten how confusing this is.

I wish there were more visual cues, like gradients and whatnot. I think axis labels still can disappear offscreen, that's not good (and should be trivial to fix too). ::sigh::

JonW
07-31-2012, 10:49 PM
Funny that it makes sense to someone from Australia. Isn't everything backward down under?

Actually if you look at the first maps drawn they had the Mediterranean Sea up the other way. This makes perfect sense as one would look "Forward" to the key thing in the sky. The Sun! So Australia would be at the top of the map in the proper position!

The very serious issue now would be that the "Map of Tassie" would be upside down! (Australian Colloquialism) & you don't get it drawn this way in ancient art. But I suspect this aspect is preferable to many!

sandman300
07-31-2012, 11:07 PM
This might sound silly but it's only inverted if your looking at it from the objects perspective. For the users perspective, everything is correct. Its a concept that started in stage productions. The director would sit in the theater's seats, and direct the actors from his perspective. Thus the term "stage left" which is actually to the actor's/actress's right.

It would actually be more confusing if it were the other way around. :D

Dexter2999
07-31-2012, 11:32 PM
This might sound silly but it's only inverted if your looking at it from the objects perspective. For the users perspective, everything is correct. Its a concept that started in stage productions. The director would sit in the theater's seats, and direct the actors from his perspective. Thus the term "stage left" which is actually to the actor's/actress's right.

It would actually be more confusing if it were the other way around. :D

Ummm....almost right

"Stage Right" is the actors right, the directors left, or "House Left". (The director being in the audience or "House".)

"Front" and "Back" well...that has nothing to do with theater. Theater uses "Up stage" (towards the back) and "Down stage" (towards the audience). This is a carry over from something called a "Raked Stage" where the stages sloped and audiences sat in a flat area. Now all theaters are the other way around. Audiences sit in sloped/stepped seating and stages are flat.

The only way I can think to explain "front" and "back" is to think as if you are standing in the middle of a line for an airline. Your "Front" is looking at the person in front of you and seeing their "Back". If you were seeing their "Front" , well....you would wonder "WTF??"

Some programmer somewhere locked in on an idea and most people just followed suite. I think the same thing about AD products using Z as the height. (Because they carried over from paper drawings where X&Y were flat drawings. Z was left to become elevation.)

jburford
08-01-2012, 12:38 AM
If my recollection is correct, many, many moons ago it was the other way around in Lightwave. If you were looking, from the front, it was labelled Back.

But perhaps my mind plays games as I get older.

biliousfrog
08-01-2012, 01:56 AM
AS
I wish there were more visual cues, like gradients and whatnot. ::sigh::

Aren't the axis letters on the grid enough of a clue? +Z is forwards, -Z is backwards, if you're modelling a car for example and its front is pointing towards -Z then it's backwards.

I admit that I still get confused by it sometimes, or rather have a brain-fart and forget, but it does make sense. Just say to yourself, "view from..." when reading the viewport labels.

JonW
08-01-2012, 02:15 AM
Sometimes the +Z -Z can be a bit hard to see with a stack of architectural drawing, & if I have a "senior moment"........ ?

But I have LW set to the previous buttons colour scheme with some slight modifications. I find this arrangement easier on the eye than the current darker monotone layout. Or maybe you can't teach an old dog new tricks!

Serling
08-01-2012, 02:17 AM
My bigger issue is with the renderer...why is every NLE set up for Lower Field first as Even and in LW it's Odd?

And yes, the back label makes no sense when viewing the front of a reference image in the viewport. It's so counterintuitive it's maddening.

Lower Fields First are Even and looking towards the front of an image or object should mean you're seeing it in the front view.

JonW
08-01-2012, 02:31 AM
Sort of a similar issue. You have a West Elevation of a building but you are facing East to view it. Or a North Elevation & facing South.

Roof & Survey drawings are viewed looking down. But the Basement drawings are not viewed from underneath looking up.

Sections quite often shift a bit left of right to pick up key features.


But I feel sorry for rowers! Port & Starboard or is that Starboard & Port?

RebelHill
08-01-2012, 04:17 AM
Bilious is right... its all about axis.

Z+ = Front, X+ = Left.

However (imagine we're looking at a compass here)... in LW Z+ = North with X+ being East. In other packages it has often been the inverse of this, or rather the Z axis is inverted... so Z+ is South and X+ is east.

The standard has always been to model things with the left side projecting into X+... in LW this means that the "front" faces Z- and the back Z+, thought the views are still named to reflect the + side.

silviotoledo
08-01-2012, 05:11 AM
althought it can make sense, I would preffer to change the labels between FRONT and BACK once it makes a little confusion while modeling.

Other problem I don't understand is why in the real scale world 1 meter in Lightwave is not 1 meter in DXF, 3Ds and OBJ format when it's exported.

lardbros
08-01-2012, 05:48 AM
All issues we face with any software I'm afraid :)

Why in CryEngine do you import objects as cm's but when you select and export a block from CryEngine it does it as metres? And every unit in the engine is measured in metres too.


Now, port and startboard... the way I remember it is:

Port is Left as they have the same amount of letters in the word. ;) And it's done as you face the bow!

JonW
08-01-2012, 06:59 AM
& so much of the computer industry is still using inches!

MAUROCOR
08-01-2012, 07:55 AM
http://forums.newtek.com/attachment.php?attachmentid=105885&d=1343819342

WOW! Nice car, Silvio! I think Lewis would be proud of it!:jester:

RebelHill
08-01-2012, 08:00 AM
Rotate your object 180deg... now front is front.

No need to thank me!

Serling
08-01-2012, 08:01 AM
althought it can make sense, I would preffer to change the labels between FRONT and BACK once it makes a little confusion while modeling.

Other problem I don't understand is why in the real scale world 1 meter in Lightwave is not 1 meter in DXF, 3Ds and OBJ format when it's exported.

Excellent illustration of the issue with the screen grab.

Serling
08-01-2012, 08:07 AM
Rotate your object 180deg... now front is front.

But then his model wouldn't be oriented the way he wanted it.

I think we've all surrendered to this idea that back is front in LW and front is front for everyone else in the known, civilized universe, but that doesn't mean I can't dream of a day when there is one meaning of "front" for every creature - great and small - everywhere.

Dream big. Aim high. :thumbsup:

RebelHill
08-01-2012, 08:18 AM
Well no... front in LW = Z+. Front in maya = Z+, front in SI = Z+...

The only difference is the switching of +/- in LW (layout). LW "decided" that it was more logical to have the Z+ space to mean "away from the viewer, into the scene space"... others chose the interpretation "toward the viewer, out from the scene". Thats all.

Plus there are other considerations beside the label in modeler. Up, Forwards, and Right are frequently referenced as (or descriptions given for) vector directions. in which case Up is Y+, Right X+ and Forward Z+. Targeting always point to front (Z+), etc. So theres a consistency of terms to consider too.

If you want the "front" of your object to align to front view in modeler, just model it facing that way if it makes that big a difference to you.

silviotoledo
08-01-2012, 08:24 AM
WOW! Nice car, Silvio! I think Lewis would be proud of it!:jester:
Yeah, but please do not share, it's my revolutionary new design for automotive industry in 2028 :). I don't want Lewis copy it :). Patent pending :).

sandman300
08-01-2012, 08:32 AM
Ummm....almost right

"Stage Right" is the actors right, the directors left, or "House Left". (The director being in the audience or "House".)

Woops, my bad, but the concept is still the same. audience perspectove vs. actor perspective. Did you ever notice that Snagglepuss gets it backwards?
http://www.youtube.com/watch?v=k4qFxTTi8q0


"Front" and "Back" well...that has nothing to do with theater. Theater uses "Up stage" (towards the back) and "Down stage" (towards the audience). This is a carry over from something called a "Raked Stage" where the stages sloped and audiences sat in a flat area. Now all theaters are the other way around. Audiences sit in sloped/stepped seating and stages are flat.

The only way I can think to explain "front" and "back" is to think as if you are standing in the middle of a line for an airline. Your "Front" is looking at the person in front of you and seeing their "Back". If you were seeing their "Front" , well....you would wonder "WTF??"

It makes sense to think your looking towards the front and see the back of a character and looking to the back and seeing the front (the house perspective).

sandman300
08-01-2012, 08:38 AM
Sort of a similar issue. You have a West Elevation of a building but you are facing East to view it. Or a North Elevation & facing South.

Roof & Survey drawings are viewed looking down. But the Basement drawings are not viewed from underneath looking up.

Sections quite often shift a bit left of right to pick up key features.


But I feel sorry for rowers! Port & Starboard or is that Starboard & Port?

I could never understand why a 2x4 is not 2" x 4".:cursin:

silviotoledo
08-01-2012, 08:40 AM
Rotate your object 180deg... now front is front.


Yeah, it solves the Ortogonal Views but the default PERSPECTIVE view is set to BACK. So another 180 degrees rotation is necessary on perspective view and the visual relation between TOP and FRONT is still a bit alien. Not sure about Chinese and Japanese people thought.


Do the Math states that +Z is front? and -Z is back? It's only a name convention but it changes completelly all the relation between the axis if Z is flipped.

silviotoledo
08-01-2012, 09:07 AM
For physics, the real image is the image upside down and the virtual image is right side up. Our eyes see upside down because of the optical principles and the science books say that the brain flips the image. Never found no evidence and no reason for the brain to do this. So it is possible that everything we see is upside down, but as everyone sees the same way no problem. In 3D this convention does not match what we're used to see and this disturbs a little.

mdharman
08-01-2012, 09:21 AM
So if you model your character facing the front (+ Z) and take him into layout, his back is facing the camera. Thought actors never wanted their butt toward the camera. Try placing the classic content cow into layout.