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Are voxels the goto method for easy mesh manipulation without worrying about vertices? I’ve been trying to research ways to 3d model without worrying about topo

Are voxels the goto method for easy mesh manipulation without worrying about vertices? I’ve been trying to research ways to 3d model without worrying about topology. So far all I’ve found is CSG and voxels.

magic_hamster 2y ago
Can you even call voxel objects a mesh?
- owenpalmer 2y ago
  Why not?
arjonagelhout 2y ago
There’s also SDF (Signed Distance Fields) modeling, such as present in multiple modeling tools like Adobe Substance 3D Modeler [0] or WOMP [1]. I suppose this is similar to voxels in that the data is stored in a uniform grid, but the way it gets rendered is different. [0] https://www.adobe.com/products/substance3d/apps/modeler.html https://www.adobe.com/products/substance3d/apps/modeler.html [1] https://womp.com/ https://womp.com/
- 01HNNWZ0MV43FF 2y ago
  SDFs don't inherently have a grid, right? You can use marching cubes to sample them along a grid, but you can also do ray marching
  - skykooler 2y ago
    It depends on the representation. SDFs can be pure mathematical functions, in which case there is no grid, or they can be a grid of values representing distances to the implicit surface, in which case they do use a grid. The latter representation, to my knowledge, is rarely used in 3d, but it is used in 2d for SDF fonts for example.
    - Jarmsy 2y ago
      A grid of values can be a sampling of an SDF, but it cannot be a true SDF itself.
      - arjonagelhout 2y ago
        From what I can find this depends on the definition, as there is a difference between a Signed Distance Function [0], and a Signed Distance Field, where the latter does get defined as a grid of values: > A signed distance field is represented as a grid sampling of the closest distance to the surface of an object represented as a polygonal model. [1] and > Signed Distance Fields (SDF) are 3D textures where each texel stores the distance from the surface of an object. By convention, this distance is negative inside the object and positive outside. [2] But that grid of values gets generated from either mathematical formulas, e.g. spheres, or from another representation of geometry such as a mesh or a vector shape. [0] https://en.wikipedia.org/wiki/Signed_distance_function https://en.wikipedia.org/wiki/Signed_distance_function [1] https://developer.nvidia.com/gpugems/gpugems3/part-v-physics-simulation/chapter-34-signed-distance-fields-using-single-pass-gpu https://developer.nvidia.com/gpugems/gpugems3/part-v-physics... [2] https://docs.unity3d.com/Packages/com.unity.visualeffectgraph@12.0/manual/sdf-in-vfx-graph.html https://docs.unity3d.com/Packages/com.unity.visualeffectgrap...
        Jarmsy 2y ago
        Some people might use the terms in this sloppy way, but not distinguishing between a field and a discrete grid sampling of that field is incorrect.
        arjonagelhout 2y ago
        That makes sense. Coming from a non-math background I wasn’t familiar with the mathematical term field. Learning something new every day :)

magic_hamster 2y ago

Can you even call voxel objects a mesh?

owenpalmer 2y ago
Why not?

arjonagelhout 2y ago

There’s also SDF (Signed Distance Fields) modeling, such as present in multiple modeling tools like Adobe Substance 3D Modeler [0] or WOMP [1]. I suppose this is similar to voxels in that the data is stored in a uniform grid, but the way it gets rendered is different. [0] https://www.adobe.com/products/substance3d/apps/modeler.html https://www.adobe.com/products/substance3d/apps/modeler.html [1] https://womp.com/ https://womp.com/

01HNNWZ0MV43FF 2y ago
SDFs don't inherently have a grid, right? You can use marching cubes to sample them along a grid, but you can also do ray marching
- skykooler 2y ago
  It depends on the representation. SDFs can be pure mathematical functions, in which case there is no grid, or they can be a grid of values representing distances to the implicit surface, in which case they do use a grid. The latter representation, to my knowledge, is rarely used in 3d, but it is used in 2d for SDF fonts for example.
  - Jarmsy 2y ago
    A grid of values can be a sampling of an SDF, but it cannot be a true SDF itself.
    - arjonagelhout 2y ago
      From what I can find this depends on the definition, as there is a difference between a Signed Distance Function [0], and a Signed Distance Field, where the latter does get defined as a grid of values: > A signed distance field is represented as a grid sampling of the closest distance to the surface of an object represented as a polygonal model. [1] and > Signed Distance Fields (SDF) are 3D textures where each texel stores the distance from the surface of an object. By convention, this distance is negative inside the object and positive outside. [2] But that grid of values gets generated from either mathematical formulas, e.g. spheres, or from another representation of geometry such as a mesh or a vector shape. [0] https://en.wikipedia.org/wiki/Signed_distance_function https://en.wikipedia.org/wiki/Signed_distance_function [1] https://developer.nvidia.com/gpugems/gpugems3/part-v-physics-simulation/chapter-34-signed-distance-fields-using-single-pass-gpu https://developer.nvidia.com/gpugems/gpugems3/part-v-physics... [2] https://docs.unity3d.com/Packages/com.unity.visualeffectgraph@12.0/manual/sdf-in-vfx-graph.html https://docs.unity3d.com/Packages/com.unity.visualeffectgrap...
      - Jarmsy 2y ago
        Some people might use the terms in this sloppy way, but not distinguishing between a field and a discrete grid sampling of that field is incorrect.
        arjonagelhout 2y ago
        That makes sense. Coming from a non-math background I wasn’t familiar with the mathematical term field. Learning something new every day :)