3D Computer Graphics Lecture Notes

Introduction to 3D Computer Graphics

• Definition: 3D computer graphics or CGI involves graphics using a three-dimensional representation of geometric data stored on a computer.
• Common Terms: CGI, 3D-CGI, three-dimensional computer graphics.
• Output: Often results in 2D images, sometimes 3D images. Can be animations or real-time displays.
• Display: Typically viewed on 2D displays but increasingly on 3D displays, like in VR systems.

Key Concepts

• 3D Models: Objects in 3D graphics are models, data stored in graphical files, transformed into images via rendering.
• 3D Rendering: Converts models into 2D images or is used in simulations.
• 3D Printing: Physical representation of models.

Historical Background

• William Fetter: Coined "computer graphics" in 1961.
• Sketchpad Program (1963): Early interactive 3D graphics exploration at MIT.
• Futureworld (1976): Early computer animation displays.
• 3D Software for Home: Began in late 1970s with the Apple II.

3D Graphics Production Workflow

1. 3D Modeling: Forming models of objects' shapes, using tools like Polygonal, Patch, and NURBS Modeling.
2. Layout and Animation: Placement and movement of models within scenes, involves keyframing, inverse kinematics, and motion-capture.
3. 3D Rendering: Calculation of light, surfaces, etc., to generate images.

Modeling Techniques

• Vertices and Polygons: Basic structural elements. Models are formed from vertices creating polygons.
• Procedural and Simulation Models: Models generated procedurally or through simulations.

Animation Techniques

• Stop Motion: Includes Claymation, Lego animation, etc.
• Animation Methods: Keyframing, inverse kinematics, motion-capture.

Materials and Textures

• Materials: Define how light interacts with surfaces.
• Textures: Define surface color and features using maps (bump, normal, displacement).

Rendering Techniques

• Realistic Rendering: Simulates light transport for photorealistic images.
• Non-Photorealistic Rendering: Applies art styles for unique visuals.
• Projection: Converts 3D to 2D displays.

3D Software and Applications

• 3D Modeling Software: Used for creating and altering 3D models.
• CAD Software: Used in engineering, manufacturing, and architectural design.

Complementary Tools and Techniques

• Editing and Compositing: Programs like Adobe Premiere Pro and Final Cut Pro for video editing.
• Machinima: Using real-time graphics engines for cinematic production.

Other Types of Graphics

• Photorealistic 2D Graphics: Achieved without wireframe modeling, often indistinguishable from 3D.
• 2.5D Graphics: Restricted 3D-like environments for performance or style.

Miscellaneous

• File Formats: Various formats for 3D graphics data (e.g., .obj, .x DirectX files).
• Industry Uses: Scientific, analytical, and industrial purposes.