38 Perspective Projection

*Perspective projection* is a technique used in computer graphics, drawing, and photography to represent three-dimensional objects in two dimensions, mimicking how objects appear to the human eye. This projection creates a sense of depth by making objects appear smaller as they get further away from the viewer, resulting in the visual effects of *vanishing points* and **convergence**. Key Concepts: 1. **Vanishing Points**: In perspective projection, parallel lines in 3D space converge towards one or more vanishing points on the 2D plane. This creates the illusion of depth and distance. 2. **Convergence**: As objects move further from the viewer, their size reduces and edges converge towards the vanishing point, simulating depth. 3. **Field of View (FOV)**: The angle of view from which the scene is captured affects the perspective. A wider FOV makes objects appear smaller and more distorted, while a narrower FOV keeps objects larger and more focused. 4. **Types of Perspective**: **One-point Perspective**: All lines converge to a single vanishing point, typically used for objects directly facing the viewer. **Two-point Perspective**: Lines converge to two vanishing points, often used to depict objects at an angle to the viewer. **Three-point Perspective**: Involves three vanishing points, often used to depict tall buildings or objects viewed from an extreme angle (both horizontally and vertically). Applications: **Architecture and Design**: In technical drawings and 3D modeling, perspective projection helps visualize objects in a realistic manner. **Photography**: Cameras capture the world through perspective projection, with distant objects appearing smaller. **Computer Graphics and Game Design**: In 3D rendering, perspective projection is used to simulate how objects appear in real life, creating a more immersive and realistic environment. Example: In a *one-point perspective* drawing, roads or railroad tracks appear to converge towards a single vanishing point in the distance, simulating how they would look if you were standing on them. Conclusion: *Perspective projection* creates realistic depth in 2D images by mimicking how the human eye perceives objects in 3D space. By using vanishing points and converging lines, this technique brings a sense of realism to visual representations, widely used in art, design, photography, and computer graphics.