Computer Graphics — Exam Power Notes
Quick Revision Guide
Definition: Computer graphics is the creation, manipulation and display of visual images using computers.
1. Graphics Types
• Raster graphics use pixels and may lose quality when enlarged.
• Vector graphics use mathematical shapes and paths, so they scale well.
• 2D graphics use width and height; 3D graphics also represent depth.
2. Display Basics
• Resolution is the number of pixels in an image or display.
• Aspect ratio compares width to height.
• A pixel is the smallest addressable element of a raster image.
• Refresh rate describes how often a display updates per second.
3. Graphics Primitives
• Points, lines, circles, polygons and curves are basic drawing elements.
• Polygons are described by vertices and edges.
4. Transformations
• Translation moves an object.
• Scaling changes its size.
• Rotation turns it around a point or axis.
• Reflection mirrors an object.
• Shearing slants its shape.
• Matrices can represent and combine transformations.
5. Viewing and Projection
• Viewing maps a scene into a view suitable for display.
• Projection maps 3D points onto a 2D surface.
• Orthographic projection preserves parallel lines.
• Perspective projection makes distant objects appear smaller.
• Clipping removes parts outside a viewing region.
6. Rendering and Shading
• Rendering creates an image using geometry, materials, lights and a camera.
• Flat shading assigns a simple shade per polygon.
• Gouraud shading interpolates vertex colors.
• Phong shading interpolates normals for lighting calculations.
• Textures add surface detail.
7. Curves and Surfaces
• Bezier curves use control points.
• Splines create smooth piecewise curves.
• Surface models represent 3D forms.
Quick Revision Guide
Definition: Computer graphics is the creation, manipulation and display of visual images using computers.
1. Graphics Types
• Raster graphics use pixels and may lose quality when enlarged.
• Vector graphics use mathematical shapes and paths, so they scale well.
• 2D graphics use width and height; 3D graphics also represent depth.
2. Display Basics
• Resolution is the number of pixels in an image or display.
• Aspect ratio compares width to height.
• A pixel is the smallest addressable element of a raster image.
• Refresh rate describes how often a display updates per second.
3. Graphics Primitives
• Points, lines, circles, polygons and curves are basic drawing elements.
• Polygons are described by vertices and edges.
4. Transformations
• Translation moves an object.
• Scaling changes its size.
• Rotation turns it around a point or axis.
• Reflection mirrors an object.
• Shearing slants its shape.
• Matrices can represent and combine transformations.
5. Viewing and Projection
• Viewing maps a scene into a view suitable for display.
• Projection maps 3D points onto a 2D surface.
• Orthographic projection preserves parallel lines.
• Perspective projection makes distant objects appear smaller.
• Clipping removes parts outside a viewing region.
6. Rendering and Shading
• Rendering creates an image using geometry, materials, lights and a camera.
• Flat shading assigns a simple shade per polygon.
• Gouraud shading interpolates vertex colors.
• Phong shading interpolates normals for lighting calculations.
• Textures add surface detail.
7. Curves and Surfaces
• Bezier curves use control points.
• Splines create smooth piecewise curves.
• Surface models represent 3D forms.
