3D Modelling Concepts PDF

Modelling Concepts 3D Modelling Games and Multimedia Author: Alexandrino Gonçalves Last revision: 25/09/2024  Computer Modelling Computer modelling is: Sculpting Spatial Description Placement of virtual 3D objects, environm...

Modelling Concepts 3D Modelling Games and Multimedia Author: Alexandrino Gonçalves Last revision: 25/09/2024  Computer Modelling Computer modelling is: Sculpting Spatial Description Placement of virtual 3D objects, environments and scenes with a computer system 3DM 2  Conventions 3D modelling practice most of the same conventions used in any field of 3D modelling For example, architects and masons have conventions to accurately: Measure spaces Build objects Arrange them in structures 3DM 3  Workspace/Scene The main reference point of our world is entitled world origin Normally is in the center of the workspace 3DM 4  3D Object What defines any 3D object? Width Height Depth Each of these dimensions will be associated to an axis in the world workspace 3DM 5  Cartesian Coordinate System The precise location of an object in the 3D world is defined using a combination of the coordinates of those three axis, usually represented as (x, y, z) Descartes referred it as Cartesian Coordinate System The values within these axis can be positive or negative Example: (14, -5, 2) 3DM 6  Coordinate Systems But, besides the cartesian coordinate system, there are other coordinate systems: Azimuthal Spherical (3D) Polar (2D) … 3DM 7  Azimuthal Coordinate System Normally used to describe the exact position of objects in the sky, such as planets, the Sun… It is expressed in terms of altitude (or elevation) angle and azimuth 3DM 8  Spherical Coordinate System Normally useful for placing and moving cameras and light sources With this system, a point is represented by the ordered triple (r,θ,ϕ), where r≥0 , 0≤θ