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3D in Voxelers
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Understand Signed Distance Fields (SDF) in CG and its implications #25

Open acs opened 3 years ago

acs commented 3 years ago

SDF

http://jamie-wong.com/2016/07/15/ray-marching-signed-distance-functions/ SDF and Ray Marching (https://github.com/stasilo/retrace.gl)

https://renderdiagrams.org/2017/12/28/signed-distance-fields/

How does it compare to marching cubes? does it need polys? What is the relations to voxels?

For example, some thoughts about howto convert SDF to a mesh.

3D GPU Gems: https://developer.nvidia.com/gpugems/gpugems3/part-v-physics-simulation/chapter-34-signed-distance-fields-using-single-pass-gpu

acs commented 3 years ago

It is all about shape modelling

acs commented 3 years ago

https://www.alanzucconi.com/2016/07/01/signed-distance-functions/ SDF is a kind of vectoral descriptions of models: describe the model using maths, not with tons of triangles. Like defining a 2D image with in a vectorial way, not using tons of pixels.

acs commented 3 years ago

A paper which covers voxels and SDF and volumes ... interesting: https://arxiv.org/pdf/1906.06543.pdf And pretty recent: 2019 "Image-based 3D Object Reconstruction"

acs commented 3 years ago

Ray tracing and SDF

https://www.sebastiansylvan.com/post/ray-tracing-signed-distance-functions/ (Haskell code)

http://bentonian.com/teaching/FGraphics1819/1.%20Ray%20Marching%20and%20Signed%20Distance%20Fields.pdf Benefits of using SDF for Ray Tracing and great intro to SDF modelling

Raymarching SDF: https://iquilezles.org/www/articles/raymarchingdf/raymarchingdf.htm (2008-2019) and basic SDF https://iquilezles.org/www/articles/distfunctions/distfunctions.htm iquiles seems to be a reference in SDF (he is also referenced for example in https://devtalk.blender.org/t/sdf-functions/11055)

SDF in reedit thread: https://www.reddit.com/r/gamedev/comments/4uzxaq/3d_models_with_zero_vertices_welcome_to_signed/ (2016) Quite interesting.

acs commented 3 years ago

Samples in Shadertoy: https://www.shadertoy.com/results?query=tag%3Dsdf

acs commented 3 years ago

Dec 2019 a patch for adding SDF functions to Blender was proposed: https://devtalk.blender.org/t/sdf-functions/11055

Blender supports Metaballs for a long time (Metaballs are defined with a kind of SDF I have understood).

acs commented 3 years ago

Godot

https://godotengine.org/article/godot-40-gets-sdf-based-real-time-global-illumination (reedit)

acs commented 2 years ago

In MagicaCSG it is used now for modelling 3d objects: https://ephtracy.github.io/index.html?page=magicacsg#ss-carousel_ss