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martov
09-13-2010, 03:28 PM
hi guys, I have been trying to make some normal maps for some time now, without success, so today I decided to make a test and bake a simple cube with some beveled faces to a simple "low poly" cube.

first, the normal map appears to have errors (red lines) , but I fail to notice what causes them
and second, there are little artifacts that shouldn't be in the map.

these are the two cubes, the low poly cube has been uvmapped
http://www.uploadfilesystem.com/thumbs/10/09/13/tn_9zS45703.jpg (http://www.uploadfilesystem.com//viewimage.php?file=/imagenes/10/09/13/9zS45703.jpg)

this is the cube's UV map
http://www.uploadfilesystem.com/thumbs/10/09/13/tn_Hez45880.jpg (http://www.uploadfilesystem.com//viewimage.php?file=/imagenes/10/09/13/Hez45880.jpg)

I placed the low poly cube to overlap the high poly cube, and applied a projection modifier, and pushed the cage to contain both models.
http://www.uploadfilesystem.com/thumbs/10/09/13/tn_GOK45747.jpg (http://www.uploadfilesystem.com//viewimage.php?file=/imagenes/10/09/13/GOK45747.jpg)

this are the "bake to texture" options I selected
http://www.uploadfilesystem.com/thumbs/10/09/13/tn_02z45958.jpg (http://www.uploadfilesystem.com//viewimage.php?file=/imagenes/10/09/13/02z45958.jpg)

this is the result of the bake, notice the red lines and that there are pieces missing(the red box was drawn by the renderer, not by me)
http://www.uploadfilesystem.com/thumbs/10/09/13/tn_8OU46003.jpg (http://www.uploadfilesystem.com//viewimage.php?file=/imagenes/10/09/13/8OU46003.jpg)


I applied the normal map to the low poly cube, and weird "holes" appear.

http://www.uploadfilesystem.com/thumbs/10/09/13/tn_Wpv46083.jpg (http://www.uploadfilesystem.com//viewimage.php?file=/imagenes/10/09/13/Wpv46083.jpg)

I dont know what else to do, im confused, the tutorials I saw did similar things, but I just can't get it to work properly

any help is appreciated, thanks!

Rahl
09-14-2010, 03:25 PM
Heya,

The technique you are using is the more precise but harder one.

The fastest way to create efficient normal maps is by:


--- Unwrap the 3D asset.

--- Create a grayscale bump map.

--- Do not use extreme variations of shades of black and white or the bump mapping will show.

--- Convert the grayscale bump to a normal map using the Nvidia filter in PS or the equivalent in any other 2D package.

--- Apply the normal map to the asset in the Bump Map swatch.

--- Set the strenght of Bump to something around 30, anything under that will be very hard to perceive.

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09-14-2010, 03:25 PM
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