Polygon Computer Graphics: Exploring the Intersection of Polygon Computer Graphics and Computer Vision

By Fouad Sabry

What is Polygon Computer Graphics

Polygons are used in computer graphics to compose images that are three-dimensional in appearance. Polygons are built up of vertices, and are typically used as triangles.

How you will benefit

(I) Insights, and validations about the following topics:

Chapter 1: Polygon (computer graphics)

Chapter 2: Wire-frame model

Chapter 3: Gouraud shading

Chapter 4: Binary space partitioning

Chapter 5: Texture mapping

Chapter 6: Shading

Chapter 7: Polygon mesh

Chapter 8: Shader

Chapter 9: Level of detail (computer graphics)

Chapter 10: Graphics pipeline

(II) Answering the public top questions about polygon computer graphics.

(III) Real world examples for the usage of polygon computer graphics in many fields.

Who this book is for

Professionals, undergraduate and graduate students, enthusiasts, hobbyists, and those who want to go beyond basic knowledge or information for any kind of Polygon Computer Graphics.

• Language: English
• Publisher: One Billion Knowledgeable
• Release date: May 14, 2024

Book preview

Chapter 1: Polygon (computer graphics)

The field of computer graphics makes use of polygons in order to create visuals that have the impression of being three-dimensional.

Polygons are typically triangular in shape, but this is not always the case. Polygons are created when the surface of an object is modeled, vertices are selected, and the item is drawn using a wire frame model. Compared to a shaded model, this is more quickly displayed; hence, the polygons constitute a stage in the process of computer animation. It is the number of polygons that are rendered in each frame that is referred to as the polygon count.

With the introduction of the fifth generation of video game consoles, the utilization of polygons became more widespread, and with each successive generation, the complexity of polygonal models increased.

Point

Floating Point

Fixed-Point

Polygon

Due to the process of rounding, each scanline has its own direction in space and can display either its front or rear side to the observer according to their preference.

Mathematical concept of fraction

Bresenham's line algorithm

There is a requirement to divide polygons into triangles.

If the spectator looks at the entire triangle, they will see the same side.

Mathematically speaking, the point numbers that were obtained from the transform and illumination stage need to be transformed to fractions.

The mathematical concept of barycentric coordinates

Used in raytracing

{End Chapter 1}

Chapter 2: Wire-frame model

In the field of three-dimensional computer graphics, a wire-frame model, also known as a wireframe model, is a graphical representation of a three-dimensional third-dimensional physical entity. Either by identifying each edge of the physical item at the point where two mathematically continuous smooth surfaces meet, or by connecting the constituent vertices of an object using (straight) lines or curves, it is possible to make it. The object is rendered by drawing lines at the locations of each edge, which leads to the projection of the item into the screen space. The use of metal wire by designers to portray the three-dimensional geometry of solid items is where the word wire frame originates from that practice. Computer models that are constructed using wire frames in three dimensions make it possible to construct and manipulate solids and solid surfaces. Conventional line drawing is inferior to the efficient and high-quality representations of solids that may be drawn using 3D solid modeling.

The depiction of the underlying design structure of a three-dimensional model is made possible through the utilization of a wire-frame model. By rotating the object in the suitable manner and selecting concealed line removal through the use of cutting planes, it is possible to get traditional two-dimensional views as well as drawings and renderings.

Wire-frame renderings are frequently utilized in situations when a relatively high screen frame rate is required. For example, when dealing with a very complicated 3D model or in real-time systems that represent outside phenomena, wire-frame renderings are utilized since they are relatively easy and quick to calculate. Surface textures can be automatically added after the initial rendering of the wire frame has been completed, which is applicable in situations when a higher level of graphical detail is desired. A designer is able to swiftly evaluate solids, rotate objects to different views, and even process faces and simple flat shading thanks to this. This eliminates the lengthy delays that are involved with displaying more realistic images.

Additionally, the wire frame format is a popular choice for programming tool paths for direct numerical control (DNC) machine tools because it is perfectly suited for this purpose.

There are images that resemble wire frames that were drawn by hand and date back to the Italian Renaissance. Wire-frame models were also utilized extensively in video games during the 1980s and early 1990s to depict three-dimensional things. This was done during a time when properly filled three-dimensional objects would have been too complicated to calculate and draw with the processors that were available at the time. CAM, which stands for computer-aided manufacturing, also makes use of wire-frame models as an input.

The wire frame model is the most abstract and least realistic of the three primary types of computer-aided design (CAD) models that are used in three-dimensional design. The surface and the solid types are the other types. When it comes to modeling, the wire-frame method is comprised solely of lines and curves that act as connections between the points or vertices, thereby defining the boundaries of an item.

The Vertex Table and the Edge Table are the two tables that are used to create an object's specifications.

The coordinate values for each vertex in three dimensions, with reference to the origin, are included in the vertex table.

Using an edge table, one may determine the beginning and ending vertices of each edge.

A simplistic interpretation may produce a wire-frame representation by only drawing straight lines between the screen coordinates of the appropriate vertices by making use of the edge list.

Face information is not supplied, in contrast to representations that are geared for more complex rendering; instead, it must be estimated if it is required for solid rendering.

To convert the three-dimensional coordinates of the vertices into the two-dimensional coordinates of the screen, the appropriate computations need to be carried out.

{End Chapter 2}

Chapter 3: Gouraud shading

Gouraud shading, named after Henri Gouraud, is an interpolation technique employed in computer graphics to generate continuous shading of surfaces represented by polygon meshes. In practice, Gouraud shading is utilized most frequently to generate continuous lighting