|Photo realistic model surfacing © copy right of Giulio Porta 2/25/2003 all rights reserved.|
|Even though this tutorial
was written specifically for A:M, the general concepts it presents are
applicable to other 3D programs. Please refer
to a particular program's manual to find out exactly how mapping
is implemented. Mapping refers to the application of bitmaps to a 3D
model. Animation Masters has several choices concerning types of bitmap
application: Color, Bump, Diffuse, Specular Size, Specular Intensity,
Transparency, Ambiance, Cookie Cut, Roughness, Displacement, and
There is no room in this tutorial for example of all of these types of maps, also not all of them are equally effective in creating photo realism. Color, Bump, Diffuse, and Specular usually are.
They are the foundation of your model surface. A photo, a scan, or a hand painted bitmap can be used for a Color Map. There are several strategies involved in creating these maps. They are usually painted on top of a template, which is usually a screen capture of the model's wire frame that is going to be applied to. The should have a dominant color, and modifications that will make them suitable to be applied to the model according to specific UV coordinates. To the front and back of the model and to various parts of the model one at the time. This is usually the case with a standing figure that cannot be mapped all at once with a single bitmap.
Bump maps are basically elevation maps, where the light areas will look raised from the surface and dark areas will look like depressions. They are usually created by converting a Color Map to a Grayscale image. Wrinkles, skin imperfections, scars and the like can be simulated with Bump Maps.
A diffusion map can be used to reduce the spreading of a color bitmap on to the model's surface.
default the diffusion map is set to 100% but on human skin, very rarely
that is the case, set the diffusion to less than 100%, try 85% and
render to see the results.
In doing so the model's surface will appear darker and richer.
A specular map tells the surface will parts will be shiny and which are dull. The white or light gray areas will be the shiniest. This map can be developed from the bump map by adding more white areas in specific places. A Specular map can also give to the model a wet look.
The Reflectivity map will cause the environment that surrounds the object to reflect on the object surface, variations on any of the maps listed here above will produce varying effects as a Reflectivity map. Reflectivity is not one of the qualities of human skin, therefore this type of map should not be included in the set of maps used to emulate realistic skin qualities.
|In this case the bump map was reapplied as a Reflectivity map.|
How bitmaps are applied.
Bitmaps are usually applied to a Flatten portion of the model, starting with version 9 UV projection mapping tools have been added to A:M, I do not have a tutorial dealing with there new built in tools as yet, but for now you can refer to this excellent tutorial by Zandoria Studios.
|The assumption here is
that you have familiar with the concept of Flattening portions of a
model, and that you have read the two tutorials I have available for
you, on that subject, one involves flattening
a face, the other flattening
The painting of decals is done in programs like Adobe Photoshop or Paint Shop Pro, and they are usually a combination of hand painted photo manipulated images, these images have to fit the model's mash (wire frame) perfectly, in terms of content, and they should also be designed to cover more than the flatten portion of the model, so they will not fall short as well as blend with other maps designed for other parts of the model.
|R + click on the model icon and select New > Decal > Other, browser for the Color decal, it should be in the same folder as your Rotoscopes, and the word Color should appear in its name.|
|Load and apply each decal one at the
time, in the following order: Color, Bump, Diffuse, Specular.
In the Decal folder you will see each decal appearing in the sequence that you have loaded them, with the default name Decal1, Decal2, Decal 3, Decal 4, it would be a good idea if those decal will be renamed for what they are.
|Click on the + sign on the right of the
Decal icon (the white star) to expand it tree. A branch of the Decal is
a folder named Images.
Click on the + sign on the right of the Images folder to open another branch (represented by icon with a landscape with a cactus) the name of the bitmap you have chosen will appear next to that icon.
|By default the first bitmap that you
will apply is of the Color type.
After applying the second one, just like before R + click on the model icon and select New > Decal > Other, browser for the Bump decal....you'll need to specify that this new map will be of the Bump type.
Expand the Image icon tree and click on the white arrow on the right of the image icon the arrow will open a roll out menu, click on Type, that will open another roll out menu, from where you can select the Bump type as the desired type of bitmap.
|There are many other variables that will come into play concerning the final appearance of your model surface. Like the Percent that can be assigned to each map type.|
|To have a better idea
concerning how your model will look like in its final version, drag and
drop the model in the choreography, please read the choreography
All the changes made to the model and its surface will be updated in the choreography, you just have to keep rendering the scene.
Pick rendering icon the middle and R + drag on the area you want to render.
In this environment the number type color and strength of the light used in staging your model will also effect it final appearance.