Computer Graphics 1 Prelim

Computer graphics

This describes the use of computers to create and manipulate images

Modeling

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

Rendering

This 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

Is an array of pixels (picture elements) displayed on a screen, arranged in a grid with two (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

0

a value of _____ indicates that no amount of that color exists

1

value of _____ represents that color is displayed at full intensity

Resolution

It is the number of pixels in the raster

Precision

It is the number of bits used for each pixel

buffer (or data buffer, or buffer memory)

A _______ is a part of a computer's memory that serves as temporary storage for data while being moved from one location to another.

framebuffer

A _____ may contain multiple buffers that store different types of data for each pixel

color buffer

At a minimum, the framebuffer must contain a ______, which stores RGB values

Depth buffer

When rendering a 3D scene, the framebuffer must also contain a _______.

• A _____ 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).

Thus, these values can also determine whether the points on each object will be visible when the scene is rendered.

Stencil buffer

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

frame

Animations consist of a sequence of images quickly displayed. Each of the images that is displayed is called a _______

frame rate

The speed or rate at which these images appear is called the _____, and is measured in frames per second (FPS)

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 are called _______. These are used to perform many different computations required in the rendering process.

Application programming interface (API)

Shader programming languages implement an ________, which defines a set of commands, functions, and protocols that can be used in interacting with an external system sunch 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 –

_______ is the most widely adopted graphics API

Graphics pipeline

Is an abstract model used to describe a sequence of steps needed in rendering a three-dimensional scene.

• increase the efficiency of the rendering process, enabling images to be displayed at faster rates

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

Vertex

The properties or attributes that are specific to rendering each individual point are grouped together into a data structure

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

Rasterization

Determining which pixels correspond to the geometric shapes to be rendered

primitive assembly

The process of grouping points into geometric primitives is termed _____

fragment

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

fragment shader

This applied to each of the fragments to calculate their final color. This calculation may involve a variety of data stored in each fragment, in combination with data globally available during rendering

Pixel Processing

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

Stage 1: Application

This stage primarily involves processes that run on the CPU

Stage 2: Geometry Processing

The shape of a geometric object is defined by a mesh, a collection of points that are grouped into lines or triangles.

Stage 3: Rasterization

Once the vertex shader has specified the final positions of each vertex, the _______ stage begins. The points themselves must first be grouped into the desired type of geometric primitive: points, lines, or triangles, consisting of sets of 1, 2, or 3 points. For lines and triangles, additional information must be specified.

Stage 4: Pixel Processing

The primary purpose of this stage is to determine the final color of each pixel, storing this data in the color buffer within the framebuffer