Scanline

Description of my graduation final work

For the final graduation dissertation we studied and developed a system to create computer-generated images through the use of a scene specification language with modeling characteristics. We implemented the system using Scanline Algorithm with Z-buffer and we specified the modeling language and implemented it through yacc and lex compilers.

To create an image it is necessary to perform some steps that start from a scene specification until it generates information that could be understood by the system. It is necessary to go through geometric transformations to go from a three-dimensional information to a bi-dimensional image. It is also necessary to analyze the optic characteristics to generate more realistic images.

Figure: One of the images generated by our implementation.

The final work covered the logical components indicating their relationship with the implementation. We covered the following topics:

• An introduction to what is computer-generated images, trying to bring the reader to the context of computer graphics.

• The modeling principles their characteristics. We covered the two main modeling methods: Gouraud and Phong.

• The projection principles covering virtual camera and the scene transport from a three-dimensional to a bi-dimensional space.

• We covered the illumination methods used to color a point over the surface, considering the interaction between the surface and the environment and the light.

• The technique to color the entire surface applying a illumination model.

• The three principal scanline algorithms, starting with a simple one to fill in the polygons, the others designed to remove hidden surfaces and finally to generate three-dimensional images.

• The implementation it-self and the correlation with main concepts.

• The language specification, the modeling properties and how the compiler works.