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This pottery simulator is all done using shaders 
Here's a thread of how I did it
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Here's a thread of how I did it
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I start with a shader that can project (orthographic) any object onto a cylindrical surface.
This is done by taking an object's world xyz coords, mapping them to cylindrical coords, and rendering them to a texture.
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This is done by taking an object's world xyz coords, mapping them to cylindrical coords, and rendering them to a texture.
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The colour of the projection is then calculated based on how far each vertex is from the surface of the cylinder. Sorta like a depth map.
By not clearing the texture every frame, you can keep track of where the hand has moved inside the cylinder.
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By not clearing the texture every frame, you can keep track of where the hand has moved inside the cylinder.
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This texture can be used as a displacement map on the cylinder. This lets you press into the mesh to deform it.
Surface normals can then be generated in the shader from the displacement map.
I could have used tessellation here, but was too lazy
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Surface normals can then be generated in the shader from the displacement map.
I could have used tessellation here, but was too lazy
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Now here's the fun part.
By simply scrolling the texture horizontally, you get the illusion of the cylinder rotating.
It looks like you're deforming a moving mesh.
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By simply scrolling the texture horizontally, you get the illusion of the cylinder rotating.
It looks like you're deforming a moving mesh.
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If you scroll the texture fast enough you get a really convincing effect. Setting the material roughness close to 0 gives that wet clay look.
While this technique doesn't support pulling the clay upwards or outwards (yet), I'm amazed by how well it works!
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While this technique doesn't support pulling the clay upwards or outwards (yet), I'm amazed by how well it works!
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The best part of my pottery shader is that it works with any object.
It's super precise and doesn't rely on colliders at all!
It's super precise and doesn't rely on colliders at all!
