THE HELL OF DEPTH SORTING PROBLEM !

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ElChristou
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THE HELL OF DEPTH SORTING PROBLEM !

Post #1by ElChristou » 08.12.2006, 13:15

:evil: I cannot stand anymore depth sorting specialy after this:

Last night I was doing a first test for a reentry addon for the shuttle, and I get a promising result with a emissive true model badly mapped (for test purpose):

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This morning, I edit a bit the model, remap it and...

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:x... A #%!& depth sorting bug appear from nowhere!!!!!
What the hell is happening????????
There is nothing (apparently) really different between both models!!! I don't understand... :evil:
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selden
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Re: THE HELL OF DEPTH SORTING PROBLEM !

Post #2by selden » 08.12.2006, 14:41

Most of the problems I've been seeing happen at close distances. If the viewpoint is further away, things are rendered properly. Your problems may be different, though.

p.s. and don't forget that translucent surfaces are known to still have problems. I just go ahead and do the model as it "should" be and don't worry about them. They'll be fixed. Eventually.
Selden

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ElChristou
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Re: THE HELL OF DEPTH SORTING PROBLEM !

Post #3by ElChristou » 08.12.2006, 14:50

selden wrote:Most of the problems I've been seeing happen at close distances. If the viewpoint is further away, things are rendered properly. Your problems may be different, though.

p.s. and don't forget that translucent surfaces are known to still have problems. I just go ahead and do the model as it "should" be and don't worry about them. They'll be fixed. Eventually.


The problem is that both are seen from similar distance... I've done further test, today no way to get the dept sorting right... (perhaps tomorrow!! :twisted:)

I cannot continue the model because I need to see the texture within Celestia to tune it... :x
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selden
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Post #4by selden » 08.12.2006, 14:57

What happens if you move the viewpoint far away from both objects and increase the magnification?
Selden

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ElChristou
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Post #5by ElChristou » 08.12.2006, 15:23

Nothing, the bug is identical, same rendering...
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dirkpitt
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Post #6by dirkpitt » 08.12.2006, 15:32

The reentry effect looks fantastic! 8O 8O

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Post #7by ElChristou » 08.12.2006, 16:10

dirkpitt wrote:The reentry effect looks fantastic! 8O 8O


Indeed it was promising... :cry:
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chris
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Post #8by chris » 08.12.2006, 17:50

It should be possible to make this work with the existing code. When two objects overlap, Celestia will draw the opaque one first followed by the translucent one. I think that the problem here is that Celestia has a hard time telling if an object is translucent if it has to look at the texture to do so, i.e. the opacity of the material is 1.0, but the texture has transparent parts. If you give me a link to an ASCII cmod for the fire, I might be able to tweak the material definition for you so that Celestia knows that it's translucent. Or, you may be able to do something in your modeler by assigning the reentry fire an opacity of 0.99 or something.

--Chris

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Post #9by ElChristou » 08.12.2006, 18:29

chris wrote:It should be possible to make this work with the existing code. When two objects overlap, Celestia will draw the opaque one first followed by the translucent one. I think that the problem here is that Celestia has a hard time telling if an object is translucent if it has to look at the texture to do so, i.e. the opacity of the material is 1.0, but the texture has transparent parts. If you give me a link to an ASCII cmod for the fire, I might be able to tweak the material definition for you so that Celestia knows that it's translucent. Or, you may be able to do something in your modeler by assigning the reentry fire an opacity of 0.99 or something.

--Chris


I'll send you the model...
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Cham M
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Post #10by Cham » 08.12.2006, 20:18

I'm having identical problems with transparent parts. I was forced to abandon many addon projects because of this. :-(
"Well! I've often seen a cat without a grin", thought Alice; "but a grin without a cat! It's the most curious thing I ever saw in all my life!"


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