This is a plugin for GIMP version 2.4 and above. It allows you to
convert images into RGB normal maps for use in per-pixel lighting
applications. The goal is to completely clone NVIDIA's photoshop plugin,
with a few new useful features.
Features
Filters. These include the filters found in the NVIDIA plugin (4
sample, 3x3, 5x5, 7x7 and 9x9) with the addition of 3x3 and 5x5 Sobel and
Prewitt edge detection filters (yields the best results IMO).
Post-filtering normal scaling
Wrap mode. This allows the filters to wrap around the image. Useful
for creating normalmaps from a tiling bumpmap.
Height source. Use an average of the RGB components or the alpha
channel as the height source in the generation of the normals.
Alpha result. For RGBA images, the alpha channel can either remain
unchanged, have the height used to generate the normal written to it,
inverse height, be replaced by either 0 or 1, the inverse of the alpha
channel's current value or use the value of a grayscale image.
Conversion options including "Normalize only" for renormalizing
bumpmaps.
"Convert to height" conversion option to reclaim height maps from
normal maps (use in tandem with the Invert X and Invert Y options).
DU/DV map creation (8 and 16 bit, signed or unsigned)
Dynamic 2D preview in the interactive dialog.
Dynamic 3D preview window using OpenGL to view the normal map applied
to a lit 3D mesh. Here are some of it's features:
View normal map applied to a number of 3D meshes (quad, cube,
sphere, torus and teapot)
Shading is done with a number of bump mapping techniques (dot3,
parallax, parallax occlusion and relief mapping) using the OpenGL Shading
Language (GLSL)
Full scene navigation controls (Rotate the object, light or
scene)
Fullscreen viewing support
Specular lighting toggle with exponent slider
Ability to choose ambient, diffuse and specular light colors
Note: Previous
versions of GIMP (2.3, 2.2) are no longer supported. You will need to
upgrade to GIMP 2.4 to use this plug-in.
To compile the source, refer to the INSTALL file provided in the source
package and make sure you have everything you need installed. The GNU Makefiles
should work on every system that has GNU make installed. Sorry, no MSVC
project/nmake files included. I don't own it, so you are on your own.
Anonymous Subversion
You may also get the source through anonymous svn.
svn co http://nifelheim.dyndns.org/svn/gimp-normalmap/trunk gimp-normalmap
You may also view the svn repository in your web browser here.
Changes
1.2.1
Added "DUDV to Normal" conversion option.
Removed requirement for the GL_SGIS_generate_mipmap extension.
Various bug fixes.
1.2
Added Invert X, Invert Y and Swap RGB options
Moved "Wrap" to the new Options panel
Added "Convert to height" conversion option. This allows you to
reclaim a height map from a normal map. Use in tandem with the Invert X and
Invert Y options to get it to look right. Also, there is a "Contrast"
setting that is enabled when choosing this conversion option to allow you to
tweak the height map further. The algorithm isn't perfect, but it's a start.
New overhauled and possibly overkill 3D preview window. Too many
new features to list here. See for yourself. :)
1.0.2
Added 5x5 Sobel and Prewitt edge detection filters
Switched to GLEW for OpenGL extension loading/checking
Added Windows build support with a MinGW environment
1.0.1
Fixed RGB Bias conversion option
Fixed a possible crash with the GTK+ dialog
1.0
Added support for GIMP 2.0.x, removed support for 1.2.x and 1.3.x.
Added alpha channel source "Alpha map" which allows you to
encode a grayscale image into the alpha channel of the normal map
0.5
Higher quality 2D and 3D preview
Double sided lighting in 3D preview
More UI cleanups
0.4
Added DU/DV map creation options
More UI issues addressed
0.3
Fixed the "Normalize only" conversion method
Various UI issues fixed
0.2
Added 3D preview window for both versions
Added the Prewitt edge detection filter
Fixed bug that caused the dv portion of the filter kernels to be
inverted
Screenshots
Release 1.2 running in GIMP 2.3.4
New 3D preview window
New "Convert to height" conversion option in 1.2
Contact
Be sure to put "gimp-normalmap" somewhere in the subject line. Please do
not mail me about compiling issues. Feel free to report bugs, make
suggestions for future releases or any feedback you may have on this software.
