subject: Bump Mapping: Helps In Making Images Look Real [print this page] Bump Mapping: Helps In Making Images Look Real
This bump mapping uses simple techniques to make images look like real. This technique in computer graphics makes the image surface look apparently bumpy although it is not actually changed. This method was found out by Blinn in 1978.
In this method he introduced normal and parallax mapping to make bumps on any image. This was a far better one than the old way of making images look like real. In the old method grayscale the images though were made to look real it did not create an ambience as good as the new technique. Thus this new technique gradually replaced the old one making it quite obsolete in a few months of it being introduced.
In bump mapping as everyone knows the shape of the object in question is not modified actually. It makes the object look closer to the real image in some simple steps. From the left side a function that would define bump map is made to replicate a crumbling surface on a sphere is made but the outline of the object and shadow look like a perfect sphere. Whereas on the right side the same function is made use of to change the surface of the sphere by creating an isosurface.
This makes the sphere with both its shadow and outline look realistic.
Also the interaction of the bumpy surface and the surrounding light makes it appear a more lifelike image. For this changing the brightness of the pixels should be specified and used to give the maximum effect. The color and brightness of the pixels in question for a scene to give a 3D effect are determined by interaction of the model and the lights around it. It is calculated mathematically and using a heightmap thus rendering a particular pixel to each position the net result being a realistic image.
A lot of calculation goes into finding a correct heightmap but once done you can get the real image effect. There are two methods used for bump mapping. One is the normal mapping and is the most common method used in computer graphics and is easy to use too. Technique used thus has some limitations though. And for different kinds of effects different kinds of bump mapping are used.
The kinds of bump mapping techniques for real time bump mapping are emboss bump mapping, environment bump mapping, etc. This way the effects that are required of the ambience that is necessary are created to get the image look as close to the real as possible.
