DDS plugin:
http://registry.gimp.org/node/70
Photo2Normal Plugin:
http://registry.gimp.org/node/69
Other info to know in GIMP.
How to scale an image.
Open the image that you want to scale.
Choose Image menu, Scale image...
Set the interpolation to Sinc (Lanczos3)
Change the image size to what you need.
Press scale.
Now your image is scaled.
Normal Maps: ***You must install this plugin first before doing this.***
http://registry.gimp.org/node/69
If you find you need more bump on your texture, cause you added a rough texture or need
to highlight some roughness. Open the image that you want to make a normal map.
Choose filter menu, Map, Normal map...
Under filter dropdown choose 9x9
under the scale, change that to 10
Press ok.
The image should turn blue with an impression of the height. Undo and repeat changing
the scale to you have the desire look, if it does not look bumped enough or is to much.
Save that file as the Filename_n.DDS
That is you _N file if you need one.
Saving file: Flatten your image first. IMPORTANT.
File menu, Export as...
Type the filename with the ext .DDS
Choose the compression as above. and choose save.
Most of the time if you are not mapping photos on you meshes, then you will bake normal and diffused to start the texture creation process. Not sure that sketch up will bake things for you.
Look for theory on UV mapping models and how it is done. You may need to use a different model program Like wings 3d or fragmotion , or Blender to get these capabilities.
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