3D mesh modeling - what is it and what are its applications in modeling industrial facilities?
What is 3D mesh?
A 3D mesh is a digital representation of a 3-dimensional object made up of interconnected vertices, edges, and faces that define the shape and surface of the object in 3D space. It serves as a structural framework that describes the geometry of an object and is widely used in 3D modelling, computer graphics, and animation.
Here are the main components of a 3D mesh:
- Vertices: These are points in 3D space that define the corners or key positions on the mesh.
- Edges: These are straight lines connecting two vertices, forming the skeleton of the mesh.
- Faces: A face is a flat surface enclosed by edges. Most 3D meshes use triangular or quadrilateral faces, though more complex polygons can also be used.
A 3D mesh can be refined with additional details such as textures (to give it color or surface properties) and materials (to simulate the way light interacts with the surface).
Methods for creating 3D mesh models
Creating 3D mesh models involves several methods, each suited for different applications depending on the level of detail, complexity, and the type of model being created. Here are some of the most common methods for generating 3D mesh models: polygonal modelling, NURBS modelling, subdivision surface modelling, sculpting, procedural modelling, photogrammetry, 3D scanning, parametric modelling, voxel modelling, Boolean modelling. At Capnor, from among the listed methods, we use only those that are strictly applicable to engineering and industrial issues. Consequently, it is possible to use methods: polygonal modelling, parametric modelling, photogrammetry and 3D scanning.
These methods are often combined in practice:
- Polygonal modelling for base mesh creation, followed by digital sculpting for high detail.
- Procedural modelling and parametric modelling are great for complex structures, while scanning and photogrammetry are ideal for real-world asset creation.
The method chosen depends on the desired level of detail, precision, and application of the 3D model.
3D mesh modeling - pros and cons
Pros of 3D Mesh Modelling
- High Flexibility - 3D mesh models allow for a wide range of shapes, from simple geometric structures to highly complex.
- Detailed Surface Representation - Mesh modelling supports a high degree of detail, allowing for realistic textures.
- Compatibility with Texturing and Shading - Mesh models can easily incorporate UV mapping, which enables textures (such as images, materials, or patterns) to be applied precisely. Meshes are also compatible with various shaders and lighting techniques, allowing for highly realistic rendering.
- Optimizable for Performance - Meshes can be optimized by reducing the polygon count while maintaining essential shape and detail, which is crucial for real-time rendering in VR/AR applications.
- Software compatibility - Meshes take up little disk space compared to raw data like point clouds, which makes them compatible with many programs. Another advantage is the versatility of storage and the number of file formats in which mesh data can be saved.
Cons of 3D Mesh Modelling
- Complexity in Creation and Editing - Creating detailed mesh models can be time-consuming, especially when working on high-poly models with intricate details. Beginners might find it challenging to master.
- Mesh Topology Issues - Poor mesh topology (arrangement of polygons) can result in problems like non-uniform deformation during animation, rendering artifacts, or difficulty in applying textures. Cleaning up bad topology can be labor-intensive.
- Limited Realism in Curved Surfaces - A mesh is essentially an approximation of curved surfaces using flat polygons. This can lead to faceted appearances in areas that are supposed to be smooth unless a high number of polygons are used, which increases computational demands.
- Difficult to Modify After Creation - Once a mesh is modelled, making large-scale changes to its structure can be difficult without distorting its geometry. Unlike procedural or parametric models, where adjustments are more flexible, mesh models often require significant reworking for major changes.