3 ms·

Ah, I assume this was posted because ambient.garden was just on the front page. Re-reading it now, I think it should really have been 2 articles. I think I sti

Ah, I assume this was posted because ambient.garden was just on the front page. Re-reading it now, I think it should really have been 2 articles. I think I still like the first half, it's a reasonable dive into the detail of what motion blur is, or should be in theory. The second half is a slightly crazy, extremely condensed explanation of how the shader works for this particular "torusphere" animation based on motion blur. I find that part mainly useful because otherwise the code would be impenetrable at this point, at least to me. In retrospect the transition between the 2 parts feels a bit like jumping into a frozen lake, sorry about that!

chaboud 3y ago
I read through it and got the sense that it just jumped into one particularly odd special case bag of crazy after providing a clean explanation of motion blur as a function of shutter-angle (exposure window). I'm glad it wasn't just the glass of wine I finished. I've played with motion blur as a function of projection of 4D extrusions a few times, but the practical context (video, textures) ends up leaving it an impractical approach when compared to sampling in hardware with caching. This write up leaves me thinking "maybe just one more time".
- pierrec 3y ago
  If you're working with triangle meshes, I think the approach of extruding triangles into prisms looks promising. It allows drawing arbitrarily long trails with OK performance. Sadly it did not match the constraints of cramming the whole scene into a shader, hence the weirder volume-based techniques. Fast analytical motion blur with transparency: https://www.sciencedirect.com/science/article/pii/S0097849321000066 https://www.sciencedirect.com/science/article/pii/S009784932...
  - chaboud 3y ago
    I played with an approach like Gribel in a software abuffer engine years ago, where coverage fragment lists were already part of the picture. Combined with video textures, it's fair to say that my result was... slow. But I'm more and more inclined to take another crack at it.

chaboud 3y ago

I read through it and got the sense that it just jumped into one particularly odd special case bag of crazy after providing a clean explanation of motion blur as a function of shutter-angle (exposure window). I'm glad it wasn't just the glass of wine I finished. I've played with motion blur as a function of projection of 4D extrusions a few times, but the practical context (video, textures) ends up leaving it an impractical approach when compared to sampling in hardware with caching. This write up leaves me thinking "maybe just one more time".

pierrec 3y ago
If you're working with triangle meshes, I think the approach of extruding triangles into prisms looks promising. It allows drawing arbitrarily long trails with OK performance. Sadly it did not match the constraints of cramming the whole scene into a shader, hence the weirder volume-based techniques. Fast analytical motion blur with transparency: https://www.sciencedirect.com/science/article/pii/S0097849321000066 https://www.sciencedirect.com/science/article/pii/S009784932...
- chaboud 3y ago
  I played with an approach like Gribel in a software abuffer engine years ago, where coverage fragment lists were already part of the picture. Combined with video textures, it's fair to say that my result was... slow. But I'm more and more inclined to take another crack at it.