Beer glass scene creation
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# 1 06-03-2012 , 03:52 AM
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Mirrored Mesh texturing off-colour

Hi, I have one mesh object that I have UV unwrapped and baked.
I duplicated and mirrored this object with -1 setting, keeping in tact UV settings etc.
From there, I "reversed normals" from polygon menu without altering anything else.

Then, I applied the same baked texture from the original onto the mirrored version;
but for some reason, it is appearing much darker than the original.

Any idea what is going on? Appreciate any help!

(In the photo, the right is original, the left is the flipped with 'reverse normals'
They both have the same texture applied.)

Attached Images

Last edited by foldedpaperbird; 06-03-2012 at 03:54 AM.
# 2 06-03-2012 , 07:33 AM
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Is the mesh using the same shader? why did you flip norms? how did you create the duplicated part................dave




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# 3 06-03-2012 , 08:13 AM
Acid44
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Did you freeze transformations? If not the normal flipping will just invert the normals, when they don't need it.

@Dave - When you mirror and object at -1 scale it reverses the normals so they're all pointing inward, so they need to be flipped.

# 4 06-03-2012 , 09:29 AM
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Looks like Acid's right on this one. you duplicated and scaled in a negative direction but you probably didn't freeze the transforms (which you should after scaling it like that).

You'd normally scale in the negative, then freeze transforms then reverse the normals.




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# 5 06-03-2012 , 11:01 AM
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Looks like Acid's right on this one. you duplicated and scaled in a negative direction but you probably didn't freeze the transforms (which you should after scaling it like that).

You'd normally scale in the negative, then freeze transforms then reverse the normals.

Hi,
I did the following before exporting for game:
1. Select Mesh
2. Delete all by type> History
3. Freeze Transformers
4. Reset Transformers
5. Export

I also just tried it in the order you suggested and still getting a grey/off white model user added image

# 6 06-03-2012 , 11:03 AM
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Is the mesh using the same shader? why did you flip norms? how did you create the duplicated part................dave

Shader? hmm how would I find this out? I believe so.
I know both the original and the duplicate were exported with a blinn material.

I will attach some more photos of the issue.
One is of a plain solid white texture on the models, the other is my baked texture.

Attached Images
# 7 06-03-2012 , 11:20 AM
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Update:
When I bring the models into the game and use the local game lighting to "light" it up, they appear the same colour but ONLY when I use the lighting. Otherwise, they are still one dark and one light.

Someone is telling me it is like the lighting is inversed similar to how the model was inside out before i reversed normals. It makes sense, is this the issue? And if so, how would I go about resolving it?

I feel like I am overlooking something really silly (this is my first time mirroring/flipping after all)

Here is a photo of them lit-up inside of the game, the previous photos were in the game 'as is'

Attached Images
# 8 06-03-2012 , 11:42 AM
Acid44
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Take a look at this, it may help. I wrote it for a specific game engine, and it isn't all that well written, but maybe it can answer some things user added image And of course you'll have to adapt parts of it to match the specific engine you're exporting for

https://dl.dropbox.com/u/35400504/Mak...rt%20Guide.pdf


Last edited by Acid44; 06-03-2012 at 11:45 AM.
# 9 06-03-2012 , 12:00 PM
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Well, it seems like you guys are right about the issue being "inverted normals"
I asked around over on the game area too and got the same response.

Thing is, I froze transformers after reversing the normals. -1 causes inverted normals, right?
Reversing normals was the only way I could get my -1 mirror to not be inside out.
So essentially, it should be working fine once the transformers are frozen?

My steps are as follows
1. Ctrl+D to copy original
2. Scale to -1 for mirror image
3. Object Mode Select > Display > Normals > Reverse
4. Delete history, freeze, reset
5. Export as fbx
6. Use FBX converter to convert to dae
7. Load to game

@ Acid- Thanks, pretty anxious to read that but for some reason it won't open up for me.

Attached Thumbnails

Last edited by foldedpaperbird; 06-03-2012 at 12:36 PM.
# 10 06-03-2012 , 12:38 PM
Acid44
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Hmm, did you try saving it instead of opening in browser? It works fine for me :S

# 11 06-03-2012 , 12:42 PM
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Hmm, did you try saving it instead of opening in browser? It works fine for me :S

ha, that worked! Thanks. I will read thisuser added image

# 12 06-03-2012 , 01:22 PM
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Generally you freeze transformations first (that flips the normals) and then you reverse the normals to fix.

# 13 06-03-2012 , 02:02 PM
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Stewrt is correct, you are should freeze transforms before reversing the normals.

You need to swap steps 3 and 4, you must freeze the transforms BEFORE you reverse the normals. It is the act of freezing the transforms that reverses the normals. You even get a warning message.

You can test it to see. Go to lighting and turn off 2-sided lighting. Then make something and duplicate and scale it -1. You will see the lighting does not change. Now freeze transform on the -1 scaled part. You will get a nastygram warning parts have become inverted and the -1 scaled part will turn black. Now its normals are truly inverted so now you can reverse the normals and finally delete the history.

the order should be

1. scale -1 to flip
2. freeze transforms (now the normals are inverted)
3. reverse the normals.
4. delete the history

You were flipping steps 2 and 3.


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Last edited by ctbram; 06-03-2012 at 02:18 PM.
# 14 07-03-2012 , 01:20 AM
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Stewrt is correct, you are should freeze transforms before reversing the normals.

You need to swap steps 3 and 4, you must freeze the transforms BEFORE you reverse the normals. It is the act of freezing the transforms that reverses the normals. You even get a warning message.

You can test it to see. Go to lighting and turn off 2-sided lighting. Then make something and duplicate and scale it -1. You will see the lighting does not change. Now freeze transform on the -1 scaled part. You will get a nastygram warning parts have become inverted and the -1 scaled part will turn black. Now its normals are truly inverted so now you can reverse the normals and finally delete the history.

the order should be

1. scale -1 to flip
2. freeze transforms (now the normals are inverted)
3. reverse the normals.
4. delete the history

You were flipping steps 2 and 3.

Thank you,
I followed your steps and did the test, and I did see it turn from black back to the normal lights.
Though when I upload to game, the model is still grey.
Im beginning to think something is wrong with my initial model (though the normals are pointing outwards on that one)

# 15 07-03-2012 , 01:36 AM
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Ok the issue ended up being this:

In the 'reverse normals" option settings, mine were set to "Reverse user normals"
but needed to be set to "Preserve user normals direction"

Now I am getting a nice clean pure white mesh.

Thank you to all for your help!

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