PRELIMS H1 - Introduction to Computer Graphics

Computer Graphics

Describes the use of computers to create and manipulate images

Modeling

Deals with the mathematical specification of shape and appearance properties in a way that can be stored on the computer

Rendering

Deals with the creation of shaded images from 3D computer models

Animation

A technique to create an illusion of motion through a sequence of images

Raster

Array of pixels displayed on a screen, arranged in a grid with 2 dimensions

Pixels

Specify colors using triples of floating-point numbers between 0 and 1, which represent the amount of red, green, and blue light existing in a color

Resolution

Number of pixels in the raster

Precision

Number of bits used for each pixel

Buffer (Data buffer of Buffer memory)

Part of a computer's memory that serves as temporary storage for data while being moved from one location to another

Framebuffer

Pixel data is stored in a region of memory.

Color buffer

Stores RGB values

Depth buffer

Stores distances from points on scene objects to the virtual camera.

Depth values

Determine whether the object’s points are in front of or behind other objects (from the camera’s perspective)

Stencil buffer

Store values used in generating advanced effects, such as shadows, reflections, or portal rendering

Animations

Consist of a sequence of images quickly displayed

Frame

Each of the images that is displayed in animations

Frame rate

Speed or rate at which these images appear

Frames per second (FPS)

Measurement of the number of frames

Graphics Processing Unit (GPU)

Features a highly parallel structure that makes it more efficient than CPUs for rendering computer graphics

Shaders

Programs run by GPUs, these are used to perform many different computations required in the rendering process

Application programming interface (API)

Defines a set of commands, functions, and protocols that can be used in interacting with an external system such as the GPU

DirectX API & High-Level Shading Language (HLSL)

Used on Microsoft platforms, including the Xbox game console

Metal API & Metal Shading Language

Runs on modern Mac computers, iPhones, and iPads

OpenGL (Open Graphics Library) API & OpenGL Shading Language (GLSL)

A cross-platform library and is the most widely adopted graphics API

Graphics Pipeline

Main Definition: An abstract model used to describe a sequence of steps needed in rendering a three-dimensional scene

Other Information: Increase the efficiency of the rendering process, enabling images to be displayed at faster rates

Pipelining

Enables a computational task to be split into subtasks thus increasing overall efficiency

Application

Initializing the window where rendered graphics will be displayed; sending data to the GPU

Geometry Processing

Determining the position of each vertex of the geometric shapes to be rendered

Vertex Shader

Geometry Processing is implemented by this program

Rasterization

Determining which pixels correspond to the geometric shapes to be rendered

Pixel Processing

Determining the color of each pixel in the rendered image, involving a program called a fragment shader