🖥️Computer Aided Drafting and Design Unit 7 – 3D Modeling Fundamentals

What's 3D Modeling?

• Process of creating three-dimensional representations of objects, characters, or environments using specialized software
• Involves defining the geometry, texture, lighting, and other properties of a digital model
• Used in various industries (video games, film, architecture, product design, and engineering)
• Enables designers to visualize and iterate on concepts before physical production
• Models can be animated, rendered, or 3D printed for various purposes
• Requires a combination of technical skills and artistic creativity
• Allows for the creation of highly detailed and realistic digital assets

Key Concepts and Terminology

• Vertex: A single point in 3D space, serving as the building block for 3D models
• Edge: A line segment connecting two vertices in a 3D model
• Face: A flat surface bounded by edges in a 3D model, typically triangular or quadrilateral
• Polygon: A closed shape composed of vertices, edges, and faces, forming the surface of a 3D model
  • Polygonal modeling is a common technique in 3D modeling
• UV mapping: The process of projecting a 2D texture onto the surface of a 3D model
• Shader: A program that determines how a 3D model's surface appears when rendered, considering factors (lighting, color, and texture)
• Rigging: The process of creating a virtual skeleton for a 3D model to enable animation
• Rendering: The final process of generating a 2D image from a 3D scene, considering (lighting, shading, and camera settings)

Essential Tools and Software

• 3D modeling software: Applications used to create, edit, and manipulate 3D models (Autodesk Maya, Blender, and SketchUp)
  • Each software has its own strengths and is suited for different industries and purposes
• Graphics tablet: An input device that allows artists to draw and sculpt 3D models more intuitively using a pen-like stylus
• 3D scanners: Devices that capture the geometry and texture of real-world objects to create digital 3D models
• Rendering engines: Software that processes 3D scenes and generates final images or animations (V-Ray, Arnold, and Cycles)
• Texture painting software: Applications used to create and edit textures for 3D models (Substance Painter, Mari, and Quixel Suite)
• Version control systems: Tools that help manage and collaborate on 3D projects by tracking changes and allowing for easy iteration (Git and Perforce)

Basic Shapes and Primitives

• Primitives are the basic geometric shapes used as starting points for creating more complex 3D models
• Common primitives include (cubes, spheres, cylinders, cones, and planes)
• Primitives can be modified using various modeling tools (extrude, scale, and boolean operations)
• Cubes are often used as the base for creating rectangular objects or buildings
• Spheres are useful for creating organic shapes or objects with rounded surfaces
• Cylinders are commonly used for creating pipes, columns, or tree trunks
• Planes serve as flat surfaces for creating floors, walls, or as the base for 2D shapes

Modeling Techniques and Approaches

• Box modeling: Starting with a primitive shape and modifying it using extrusion, scaling, and edge loops to create the desired form
• Edge modeling: Creating a 3D model by manipulating individual edges and vertices to define the object's shape
• Subdivision surface modeling: Creating a low-poly base mesh and applying subdivision algorithms to generate a smooth, high-resolution model
  • Allows for efficient creation of organic shapes and smooth surfaces
• Digital sculpting: Using specialized software (ZBrush or Mudbox) to manipulate 3D models as if working with clay, allowing for highly detailed and organic shapes
• Procedural modeling: Generating 3D models using algorithms and rules, often used for creating complex patterns, textures, or large-scale environments
• CAD (Computer-Aided Design): Using precise measurements and geometric constraints to create accurate 3D models for engineering and product design purposes

Texturing and Materials

• Texturing is the process of applying 2D images or patterns to the surface of a 3D model to add visual detail and realism
• Materials define how a 3D model's surface interacts with light, including properties (color, reflectivity, and transparency)
• UV mapping is used to project 2D textures onto the surface of a 3D model accurately
  • Involves unwrapping the 3D model's surface into a 2D representation
• Common texture maps include (diffuse, normal, specular, and displacement maps)
  • Each map type contributes to a different aspect of the material's appearance
• Physically-based rendering (PBR) is a texturing approach that aims to simulate real-world material properties for more realistic results
• Procedural textures are generated using algorithms and can be used to create repeating patterns or complex surface details without manual painting

Lighting and Rendering Basics

• Lighting plays a crucial role in how a 3D scene is perceived, affecting mood, atmosphere, and realism
• Common light types in 3D software include (point lights, spot lights, directional lights, and area lights)
  • Each light type has its own properties and use cases
• Shadows are essential for creating depth and realism in a 3D scene
  • Can be computed using techniques (shadow maps or ray tracing)
• Global illumination simulates how light bounces and interacts with surfaces in a scene, creating more realistic lighting
• Rendering is the process of generating a final 2D image from a 3D scene, considering (lighting, materials, and camera settings)
• Rendering engines (V-Ray, Arnold, and Cycles) use different algorithms and techniques to calculate the final image
• Render settings (samples, resolution, and bounces) can be adjusted to balance quality and computation time

Practical Applications and Projects

• Architectural visualization: Creating 3D models and renderings of buildings, interiors, and landscapes for design and presentation purposes
• Product design: Using 3D modeling to create and iterate on product concepts, from consumer goods to industrial equipment
• Character modeling for video games and animation: Creating 3D models of characters, creatures, and props for use in games and animated films
• Visual effects (VFX) for film and television: Creating 3D assets and environments for integration with live-action footage
• Medical and scientific visualization: Using 3D modeling to create accurate representations of anatomical structures or scientific concepts for educational and research purposes
• 3D printing: Preparing 3D models for physical production using additive manufacturing techniques
  • Requires consideration of factors (wall thickness, support structures, and material properties)