HA7 Task 2 - Displaying 3D Polygon Animations

Graphical rendering is done by the Central Processing Unit (CPU), and Graphics Processing Unit (GPU). The CPU tells the GPU what to render, for example lighting or shadows.

API

Game engines use software called Application Programming Interfaces (API). API is made up of a set of routines and protocols, and even tools used for creating software applications.

Direct3D

Direct 3D is used to mold, manipulate and display 3D objects, this was developed by Microsoft and allows programmers to develop 3D programs, all PC's can support this program.

OpenGLThis a 3D graphic language which contains 2 different versions Microsoft OpenGL which is built into Windows and was made to improve performance and was made by Microsoft and then there is Cosmo OpenGL which is software only and specifically designed for machines without a graphics accelerator which was developed by Silicon Graphics.

Graphics Pipeline

A Graphic Pipeline also known as the rendering pipeline is a process of designing a 2D raster image on a 3D scene. Once this 3D model is created, it must transformed into what the monitor will allow to display, examples of Graphic Pipelines are OpenGL and Direct 3D.

Stages of a Graphics Pipeline

3D Geometric primitives
This scene is created using primitives which usually are triangles as they exist only on one plane.

Modelling and Transformation
This is when it is transformed in to a 3D co-ordinate system from local co-ordinate systems.

Camera Transformation
Then It's transformed from the 3D co-ordinate system to THE 3D camera co-ordinate system.

Lighting
The scene is then lit up according to how light the colours are and how reflective the object is. An example would be a completely white object on a black background, the lighting would need to be adjusted for that to be seen.

Projection Transformation
It is transformed from 3D co-ordinates to a 2D camera view. Distant object will be made smaller, and the camera will focus on the central object.

Clipping
This is when any primitives that can't be viewed will be removed.

Scan Conversion or Rasterization
The image is converted to a raster format, and made up of pixels. Then individual pixels can be altered, which is a very complex step.

Texturing, Fragment Shading
The individual fragments get given colors based on values given during the rasterization stage.