MeshVolume exploration #32237
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MeshVolume exploration #32237
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…rt, function or class Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>
…rt, function or class Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>
…rt, function or class Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>
Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>
Owner
Author
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62k tris mesh converted to a 64³ SDF and instanced 1000 times: 
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gkjohnson
reviewed
Nov 13, 2025
Comment on lines
127
to
151
| // Check if the point is inside or outside by raycasting | ||
| // Skip expensive raycasts for points far from surface (definitely outside) | ||
| let isInside = false; | ||
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| if ( dist < this.margin ) { | ||
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| // If we hit a back face then we're inside | ||
| let insideCount = 0; | ||
| ray.origin.copy( point ); | ||
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| for ( let i = 0; i < 6; i ++ ) { | ||
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| ray.direction.copy( directions[ i ] ); | ||
| const hit = bvh.raycastFirst( ray, DoubleSide ); | ||
| if ( hit && hit.face.normal.dot( ray.direction ) > 0.0 ) { | ||
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| insideCount ++; | ||
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| } | ||
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| } | ||
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| isInside = insideCount > 3; | ||
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| } |
Collaborator
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Just a note that checking "insidedness" can only really reliably work if the source model is water tight - has no intersecting triangles, etc. Otherwise you might get an odd pos / neg pattern.
| break; | ||
| } | ||
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| float stepSize = distanceToSurface * 0.5; |
Collaborator
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Why halve the step to the surface?
Owner
Author
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Not sure!
Without it the render would get that near clipping artifact:
https://x.com/mrdoob/status/1987814636306198581
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Description
I was always curious to see how would it be to convert a mesh into a SDF 3D texture and then render it using
MeshStandardMaterial. Finally gave it a try today.Screen.Recording.2025-11-10.at.9.41.24.PM.mov