How would you create this lighting technique? (controlling light with geo intersection)
polycounter lvl 4
Hi, I am trying to reproduce this lighting technique which I theoretically know how it's done, but I have no idea how to execute it. Right now I am using Maya, but I would also like to know if this is possible in Unity (which I have minimal experience with).
In short the shading is not controlled with physical lights but with geometry. The character has a toonshader applied. There is an invisible piece of geometry that represents where the 'light' is. Where the character intersects with this geo is where the character is in 'light'. Here is the short "Pearl" where I know the director is using a technique like this, rather than out-of-the-box toonshading. Alternatively this geo can be used just to say "render lighting completely and only in this location, all else in is shadow"
Here's a demonstration with my own rough model, I quickly drew up what sort of thing I'm looking for in photoshop.
If you all have any sort of leads let me know. Also feel free to mention anything that feels close to what I'm going for.
In short the shading is not controlled with physical lights but with geometry. The character has a toonshader applied. There is an invisible piece of geometry that represents where the 'light' is. Where the character intersects with this geo is where the character is in 'light'. Here is the short "Pearl" where I know the director is using a technique like this, rather than out-of-the-box toonshading. Alternatively this geo can be used just to say "render lighting completely and only in this location, all else in is shadow"
Here's a demonstration with my own rough model, I quickly drew up what sort of thing I'm looking for in photoshop.
If you all have any sort of leads let me know. Also feel free to mention anything that feels close to what I'm going for.
Replies
http://polycount.com/discussion/121144/convincing-3d-that-looks-like-2d-wow/p8
Jump to the last pages. If i remember correctly it's something about baking the normals of super low polies to a higher poly mesh.
Guilty gear has a good pdf on this somewhere....ah here
page 21
http://www.ggxrd.com/Motomura_Junya_GuiltyGearXrd.pdf
you'd be transferring from basically a sphere...
I just know that the technique with light shapes can be done, and is preferable in some situations, especially when framing multiple objects in light and with a specific shape. This is more for cinematic purposes.
https://simonschreibt.de/gat/zelda-wind-waker-hyrule-travel-guide/#fireflying
I'll look into this more, though I feel some of the technology explained here is a little over my head and may take time to digest. Creates a cool effect though. The stencil buffers also seem to be capable of something I couldn't find a solution to ages ago which was turning a mesh invisible where geometry intersects. Also the 'portal windows' they can create also look pretty wild.
These 3 passes are needed to build a "mask" on the stencil buffer that represents only the pixels you want to light up. Think of it like working with selections in Photoshop: you can add, subtract, intersect selections etc. and at the end you have the complex selection you want. These selections that you are making are the pixels of the sphere that is being rendered sometimes with frontface culling and sometimes with backface culling.
After the mask is ready, you can render a fullscreen quad with an additive blend and set the stencil-test to only let pixels of the quad appear when they are within the region of that mask.
You can also do the opposite: render a fullscreen quad with like a multiply blend and set the stencil-test to only let pixels of the quad appear when they are outside of the region of that mask. The whole scene is rendered lit, but the pixels outside of the mask are darkened to make them look like they're in shadow. This is kinda like stencil-buffer shadows work.