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# 1 24-12-2012 , 05:22 AM
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Problems with Normal Maps

For the past hours i have been trying to put into work the few knowledge i had on normal maps, and so far i have had nothing user added image

I was initially trying to create a diamond plate sheet to create a nice texture but i couldnt have a single normal map so i went to the basics and created a simple box beveled here and extruded there just to test out and start pin pointing the problems.

First i thouhgt something was wrong with geometry, then i used simple geometry and i thought it would be due to non existent UV map, wich i came to realise it was no problem having no UV map after the attempt on the box below. I tried connecting to the existing shader, to a new shader, and now i noticed my High Quality Renderer does not render the Normal Map, and everytime i try to turn Viewport 2.0 Maya Crashes.
Also i think the result is quite bad for what i have seen.

I attached an image of the box (high_res above low_res) beside the wireframe, with the High Quality renderer settings.
Also i have attached:
Render using Mental Ray Production Quality
Render using Maya Software Production Quality
Jpeg conversion of Targa Normal Map.

I would apreciate you can tell me where i went wrong, i've followed several video tutorials and in all of them the results are neat and alike, and in mine i cant see them in persp view high quality render, nor they look alike in any render user added image

(Not sure if i am missing anything below my nose, nor if the few information is enough for you to help me, if so i'll provide more information just ask)

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# 2 24-12-2012 , 05:39 AM
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Hmm, i did a new fast teste, and something seems defenetly wrong with this :S not sure if it is some settings or if i am missing something here :S again, i know litle about this, only some theory i had from a course i had taken and some video tutorials :S
below i attached a render with mental ray a render with maya software, and the normal map.

Suposedly the mental ray should have the best result right? still the maya software has the more aproaching result to the real one. I mean, the mental ray does have the best result, from what i have seen on the normal map, but then again why did the normal map came out bad? :S the map shows only an extruded form going out of the face of the cube instead the real thing right beside it. i checked all the normals directions and they are correctly facing away from the model.. there couldnt be a mistak in, my opinion, from a fast extruded cube. user added image

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# 3 24-12-2012 , 12:34 PM
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Have a look at the UVs see if they are flipped for the box................dave




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# 4 24-12-2012 , 06:29 PM
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hmm, what do you mean flipped UVs? do you mean the normals? i checked there a while ago and the normals are OK, the UVs are layed out like the normal map is. user added image
i thought of something, the envelope works bothsides? like to the outside of the mesh and to the inside? or the percentage you give to check for geometry only works for the outside? because on the last example i posted it seems the NMap is missing those interior faces. :S and even on the High poly mesh the normals are OK facing outwards the mesh

# 5 24-12-2012 , 11:12 PM
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How are you applying the normal map to the shader?

Jay

# 6 24-12-2012 , 11:37 PM
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the map is connected as a bump map with the option "Use As" Tangent Space Normals".
but could there be something wrong with my Maya? that is somehow doing the Maps Wrong? the normal map file seems to be "smoother" never looks like the original high res mesh :S

# 7 25-12-2012 , 02:50 PM
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It will never be exactly the same, because you are using a map as opposed to actual geo.

I'll do one and see what I can suggest. Bear with me as its christmas day, so a little busy with bottles of beer user added image and glasses of wine

Jay

# 8 26-12-2012 , 02:46 PM
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any news yet? :S could this be a Maya problem? some weird settings? altough i'd believe i havent change anything related to this..
as i said i followed several simple video tutorials on youtube and all of them got the fine results. when i try to do everything as they say something's always bad :S first i couldnt see the maps, (on the diamond plate) so i thought it could be due to strange geometry, then i tried on very simple box stuff like those prints and the maps seem to be always diferent from the original geometry, and that i mean the post with the red crate, you can notice it has on inward extrusion, then another resizing the area and an outwards extrusion. and the map was created like a simple extrusion outwards the mesh, never inwards :S

# 9 26-12-2012 , 07:45 PM
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I just twigged what you've written -you are only supposed to do this stuff with MR anyway, Maya software doesnt have the options for derivative settings for the normal map. So forget it. Also if you are having display issues and crashes with viewport 2 then its card related..its all fine this end with me

J

# 10 26-12-2012 , 08:36 PM
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well, my jaws have fallen.. :S sry for the continuous post, but after your response i went again to try on the original tread tile and not only it worked, i then tried the biger tile i had made, and it worked again. so i can only say Maya was literally moking me that day. Not only i have restarted maya that day i had no background processes runing and today i have like my PC converting videos, downloading stuff, listening to music, so i dont see any reasonable explanation :S the tread plate worked. the only "tiny" thing i made diferent was that the plane i used as source mesh had 4 divisions, while the other day i was using 1 with none. but still i dont think that made the diference :S (or did it?) after all the normal map serves as a way to reduce geo.. (about the renderer, i wasnt sure on what renderer was needed so i just tried both).
thank you anyway user added image

# 11 07-01-2013 , 07:56 PM
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Hi again.
well, i really need some help here user added image
i now did a normal map on a tire i had, and again, the normal map gives me way too less relief as it should have from the original high poly mesh user added image
any idea what must that be? :S i did evertything good, but again, the edges should go deeper, similar to the image i first posted (not the red crate one) .. :S

# 12 07-01-2013 , 09:58 PM
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Increase the deformation on the geo and make a new map, go to the deformation tab and use inflate or inflate balloon. Dont forget its a normal map, it works of surface normals like a bump map but in rgb. Better still just do a displacemnet map from the original geo and it should be the same

Jay

# 13 08-01-2013 , 07:49 AM
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for a displacement map i should have Nurbs right? but i wanted to work on polygons user added image (low poly meshes dont work well with displacement, right?)
i was able to do a nice normal map for the diamond tread, but when i tried to do for the Tire, the map itself is created with very low relief, and nothing compared to the actual geo.
i attached the highres tire (wich i actually did first) then did a low res tire, and did the normal map.
is something wrong with the workflow? or is it maya? (maybe if i upgrade to 2013) why would the map be created as if the bumps in the middle of the tire have very low height?

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# 14 08-01-2013 , 09:46 AM
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I think you need to increase the size of the low poly before you do the bake normals..............dave




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# 15 08-01-2013 , 10:38 AM
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I think you need to increase the size of the low poly before you do the bake normals..............dave

how so? i tried making the low res mech of the tire smaller than the high res, and getting the envelope to find the high res details, and tried the other way around, and both times the inner relief is almost inexistent in the normal map user added image

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