Introduction to Computer Graphics

• Computer graphics is the use of computers to create and manipulate visual content. This includes images, animations, and 3D models.
• Key applications include video games, film, advertising, and scientific visualization.
• Fundamental concepts include:
  • Raster graphics: Represent images as a grid of pixels. Common file formats include JPEG, PNG, and GIF.
  • Vector graphics: Use mathematical equations to define shapes and lines, resulting in scalable resolution and precise details, commonly used for logos and illustrations.
  • 3D modeling: Creates and manipulates three-dimensional objects using software applications. Key techniques include polygon modeling, NURBS (Non-Uniform Rational B-Splines), and subdivision surfaces.
• Key steps in creating computer graphics might include:
  • Modeling: Creation of 3D shapes.
  • Texturing: Application of surface details like colors and patterns.
  • Lighting and shading: Simulation of light interacting with objects.
  • Rendering: Transforming the 3D model into a 2D image, or a series of images for animation.

Image Representation

• Digital images are represented as a grid of pixels, each with a specific color value.
• Image resolution is determined by the number of pixels in the image (e.g., pixels per inch, PPI). Higher resolution means more detail.
• Color models, such as RGB (Red, Green, Blue) and CMYK (Cyan, Magenta, Yellow, Key), define how colors are represented numerically.

3D Modeling Techniques

• Polygon modeling: Consists of representing 3D shapes as interconnected polygons. This technique is straightforward but may not always represent complex curves or organic forms as accurately.
• NURBS (Non-Uniform Rational B-Splines): Mathematical techniques providing greater flexibility for creating complex curves and surfaces. Used in CAD (Computer-Aided Design) and animation.
• Subdivision surfaces: Generate smooth surfaces by iteratively refining polygons. Offer a balance of complexity and smoothness.
• Procedural modeling: Creates shapes and textures through mathematical algorithms, commonly used for generating complex repetitive patterns or seamlessly repeating textures like fractals.

Rendering Techniques

• Ray tracing: Calculates how light rays interact with objects in a scene to produce highly realistic images. The process involves tracing light from the viewer's eye through the scene to determine color and lighting.
• Rasterization: Projects 3D objects onto a 2D display by converting them into a series of pixels that determine color values. The technique is less computationally intensive than ray-tracing but still produces high-quality imagery.
• Photon mapping: Simulates light bouncing off objects and then tracing paths of the photons to illuminate the scene, generating visually accurate simulations of lighting and reflections.
• Global illumination: Consider all light interactions in a scene, not just those from a primary light source, for very realistic visual effect recreations.
• Ambient occlusion: Calculates the lack of ambient light in areas of a model which are obscured, improving realism and definition of depth.

Animation

• Frame-by-frame animation: Creating a sequence of images to depict movement. This is a method common in traditional animation.
• Keyframing: Specifying the states of an object at key moments within an animation. Interpolation happens between those points to build smooth motion.
• Motion capture: Capturing real-world motion and applying it to digital models for realistic animation, often seen in film and video games.
• 3D animation: Combining 3D modeling and animation techniques to create dynamic, lifelike movement in three dimensions.

Software Tools

• Diverse software tools exist for creation and manipulation in computer graphics, including 2D software for working with images and illustrations, and 3D software for modeling, rendering, and animation. Common programs may feature specific functions for specific elements like lighting, textures, or materials.

Applications of Computer Graphics

• Video games: Creating detailed virtual worlds, characters, and effects.
• Film and television: Visual effects, special effects, and interactive content/features.
• Architecture and design: Visualizing building designs and spaces.
• Medicine and science: Generating detailed medical images, simulating scientific processes, and visualising complex data.
• Advertising and marketing: Producing eye-catching imagery and animated content for commercials and promotional materials.

Explore the fundamental concepts of computer graphics, including raster and vector graphics, along with 3D modeling techniques. This quiz covers key applications such as video games and film, and essential steps in the graphics creation process. Test your understanding of how visual content is created and manipulated using computers.