Computer Graphics Prelims

Reviewer Prelims

Computer Graphics

describes the use of computers to create and manipulate images.

Modelling

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

Animation

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

Raster

is an array of pixels

framebuffer

That may contain multiple buffers that store different types of data for each pixel.

depth buffer

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

stencil buffer

used to store values used in generating advanced effects, such as shadows, reflections, or portal rendering.

Resolution

is the number of pixels in the raster

Precision

is the number of buts used for each pixel

frame

Each of the images that is displayed is called

frame rate

The speed of rate at which these images appear is called _ _ and measured in _ _ _

Graphics Processing Unit

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

shaders

Programs run by GPUs are called

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)

is the most widely adopted graphics API

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, implemented by a program known as vertex shader.

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

Vertex Array Objects (VAO)

storing this information and can be activated and deactivated as needed during the rendering process.

mesh

a collections of points that are grouped into lines or traingles.

vertex

contains the three-dimensional position of the corresponding point.

Texture coordinates or UV coordinates

which indicate a point in an image that is mapped to the vertex

normal vector

indicates the direction perpendicular to a surface and is typically used in lighting calculations

Model transformation

The collection of points defining the intrinsic shape of an object may be translated, rotated, and scaled.

World Space

The coordinate system where the origin is at the center of the scene.

View transformation

Coordinates in this context are said to be in view space.

view space (or camera space, or eye space)

is the result when world-space coordinates are transformed to coordinates in front of the user's view.

Projection transformation

Any points outside the specified region are discarded or clipped from the scene; coordinates expressed at this stage are in clip space.

primitive assembly

The process of grouping points into geometric primitives.

fragment

is a collection of data used to determine to color of a single pixel in a rendered image.

raster position

The data stored in a fragment always includes the _ _ also called pixel coordinates.

fragment shader

is applied to each of the fragments to calculate their final color.

window

is a graphical interface element that displays an application's content.

startup

during this stage, objects are created, values are initialized, and any required external files are loaded.

Main Loop

This stage repeats continuously while the application is running.

Process Input

checks if the user has performed any action that sends data to the computer, such as pressing keys on a keyboard or clicking buttons on a mouse.

Update

changes values of variables and objects.

Render

creates graphics that are displayed on the screen.

Shutdown

This stage typically begins when the user performs an action indicating that the program should stop.

Pygame

is a set of Python modules designed for creating video games. It is a popular Python game development library.

vertex buffer

A buffer that contains information like XYZ or the Normal of XYZ.

Uniform Variables

are global variables that can be accessed by the vertex shader or the fragment shader, and whose values are constant while each shape is being drawn (can be changed between draw function calls).

glGetUnifromLocation

a function that returns a value used to reference a uniform variable (indicated by the type qualifier uniform) with the name indicated by the parameter variableName and declared in the program referenced by the parameeter programRef.

keyup events

occur the moment the key is released.

discrete

isolated point in time.

continuous

continues happening or interval time.