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Ztransparency/Zoffset/Passindex issues

PostPosted: Thu Jul 24, 2008 3:35 pm
by Kierra
I'm having Ztrasnparency/Zoffset issues.

I thought I had this issue figured out, but then something went wonky when I updated--long story short, my computer crashed, had to reinstall everything--so I'm updated to Blender 2.46 and the latest PyPRP 1.5.0 and all that. After unzipping my saved .blender file from my backup drive, opening my current age Teralee and exporting it, I discovered that all my Ztransperancies had gone all wonky (trasnparencies in the background showing through transparencies in the foreground).

I've been trying to fix it, but with limited success...considering I have absolutely no clue how or why Ztrasparency works the way it does. The tutorials on the Wiki only say "set Ztransparency to such and such" setting, but doesn't explain how to layer multiple transparencies so they show through in the correct order, or even why it works that way.

Currently I have planes stacked petty much one right behind the other (more or less), each needs to be transparent. Their Zoffset numbers are currently ordered 10 (center of the age) and radiating outward to 1 on the farthest edge. I've tried it the reverse 1 as center of the age and 10 the farthest.

Like I said, I don't know how Ztransparency/Zoffset work at all, so I'm pretty much guessing here from what I've puzzled out on the wiki tutorials, and trial and error in my exports.

Can someone help me figure out how Ztransparency works, and how to fix my issue?

Thanks,
~Kia

Re: Ztransparency/Zoffset issues

PostPosted: Thu Jul 24, 2008 3:58 pm
by Jonnee
Most writers say that you should forget the Zoffs and use the Passindex (in the object panel) for the future. It works the same way. But I still prefer a mix of Passindex and Zoffs.
For explanation of Zoffs:
Please imagine a batch of paper. The bottom page can have Zoff 0. the page above Zoff 1, the next above it has Zoff 2 and so on. It also works this way if objects cover eachother horizontal.
But sometimes I have so many objects close to eachother that I use a mix of Zoffs and Passindex at the same moment. Then I try different combinations till every object will be drawn as I want it.
Someone sayd that an object with passindex 1 will get drawn earlier than an object with 2, 3, 4 and so on... Please just use the search function for explanation of that function.

Re: Ztransparency/Zoffset issues

PostPosted: Thu Jul 24, 2008 4:32 pm
by Kierra
Interesting.

My search on passindex turned up place holder spots on the wiki saying that Zoffs doesn't work with PyPRP 1.5.0, and a tutorial needed to be made on passindex.

Well that at least explains why I'm having issues...

I've never even heard of passindex however, so I have no idea on where to even start there.

Thank you for that information, I can stop beating my head against Zoffs at least :lol: Ive never liked it one little bit

~Kia

Re: Ztransparency/Zoffset issues

PostPosted: Fri Jul 25, 2008 12:46 am
by Marcello
I have been fooling around a bit with passindex and it seems to work just like z index but based on a setting per object instead of per material. Makes sense if materials are shattered across an age and are dealing with different object with alpha at different spots. Could be a drag to keep track of zindeces then.

The only problem I'm still having is with wavesets behind and alpha. Gives me jagged edges :( A problem no one seems to have solved yet.

Re: Ztransparency/Zoffset issues

PostPosted: Fri Jul 25, 2008 12:49 am
by Kato
PassIndex is the new replacement for Zoffs (although Zoffs still does something). PassIndex is per-object rather than per-material, making it a slightly better solution in this case. The slider can be found in the Object Buttons (F7). PassIndex increments the span that the object is in, and higher spans are drawn first.

Basically: objects with a higher PassIndex should be drawn first.

-Kato

EDIT: This post is mostly wrong. Read down ;)

Re: Ztransparency/Zoffset issues

PostPosted: Fri Jul 25, 2008 12:50 am
by Nadnerb
I'm pretty sure higher passindex (span index) objects are drawn later.

Re: Ztransparency/Zoffset issues

PostPosted: Fri Jul 25, 2008 12:53 am
by Kato
I thought that too, but I checked an older post of Dox's and he says otherwise. Maybe he's wrong :P

-Kato

Re: Ztransparency/Zoffset issues

PostPosted: Fri Jul 25, 2008 12:56 am
by Nadnerb
No, he's right, it appears you misinterpreted his post though.

Paradox wrote:Objects in Spans1 will be drawn in front of objects in Spans0


Objects drawn in front of others are drawn later, rather than earlier. In a perfect world, all faces are drawn back to front. In the real world, you have to set the passindex. ;)

Re: Ztransparency/Zoffset issues

PostPosted: Fri Jul 25, 2008 12:59 am
by Kato
Okay, well, when I hear drawn in front of it recalls the phrase drawn ontop of, which are grammatically pretty similar.

Thanks for the correction :)

-Kato

Re: Ztransparency/Zoffset issues

PostPosted: Fri Jul 25, 2008 1:44 am
by Marcello
Ok two questions remain:

1. what do zindex and ztransp do now?
2. if I'm working with objects that can be viewed from several angles, how to set those?