I wish ... someone to implement ... Cel-shading

[Rice]

The cel-shade texture packages for Zelda OOT and Mario 64 are looking great.

The current rendering engine of the video plugin does not support cel-shading, thus the triangles are still rendered with gouraud shading, with cel-shade type of textures.


I looked at this topic before. I thought it is not very difficult to do. For every triangle, the norm of the triangle needs to be computed, and compare against the directions of the lightings, and a flat shading should be used instead of gouraud shading, lighting will be done via a lighting texture, etc, ...

Well, it is not very easy, but is definitely do-able.

I wish I had time to do it, but I really don't have time.

Someone feels this topic is interesting should continue to discuss it here.

Reference: Cel-Shading by Sami "MENTAL" Hamlaoui

 

[Risio]

Orkin had that cel shade plugin he was working on, but he dissapeared. If I recall, he showed it off with Djipi's Cel Zelda pack.

Djipi, do you have any info on this? I'd love to see my Retro Mario 64 cel shaded!

 

[Djipi]

Orkin had send me a beta of his plugin , but even if cell shaded work well , many bug were here at the same time. I haven't seen Orkin since 2004 or 2005 i think , hope he's fine ..

But it woujld be great if someone can redo a cell shading plugin using Rice ^^ . And Rice , nice to see you ^^

 

[UnaidedCoder]

Screw cel shading, i want someone to establish model extraction and modification I can only bring it so far with textures, i'm used to working on my own models >.>

Similarly, remapping would be awesome for many games.

 

[Rice]

Model extraction is easy to do, just a matter of implementation.

Model modification/replacement is another matter. It is very similar HLE audio modification/replacement that has been discussed in other threads. Unlike to replace a texture which by itself is a complete object, a 3D object model, maybe not rendered completely alone by itself, therefore it is not easy to identify a group of vertex data as a 3D object. If we can identify such a group of triangles as a 3D model, and assuming such triangle data won't change as the scene changes, it will be possible to replace the data with a new 3D model.

I think model replacement is possible, but not 100% sure, and I guess it may work for some games, but for all games.

 

[Risio]

What I would like to know is, would it be possible to add textures in places that originally lacked textures. Such as, Mario in Mario 64. Hes all gouraud, as I'm sure you know.

Would it be possible to add textures to him?

 

[Rice]

Similar to 3D model replacement. The key is to be able to identify the 3D objects from the stream of drawing commands.

For now, I will say it is possible, but will not likely to get implemented.

 

[jmf145]

There was something like Cel-shading posted a few weeks ago that mudlord did something on, in case you missed it.
(I think pics 2-4 and 6-8 seem like a good start for "true" cel-shanding with edge detection)

http://emutalk.net/showthread.php?t=43488

oh, and it's great to see you back.

 

[M[u]ddy]

There was something like Cel-shading posted a few weeks ago that mudlord did something on, in case you missed it.
(I think pics 2-4 and 6-8 seem like a good start for "true" cel-shanding with edge detection)

http://emutalk.net/showthread.php?t=43488

oh, and it's great to see you back.

Thats not real cell-shading. It looks similar but you will never be able to get a 100% perfect image this way.
In real cell-shading the effect is applied before the image is drawn.
In the method used there, a filter is put over the ready image like in Photoshop.

 

[Gonetz]

Hello Rice,

Good to see you again!

Thanks for the topic. I’ve read briefly the reference document - it’s very interesting. I was surprised, that cel-shading is actually that simple to implement. You don’t need to code advanced shader programs, just some simple additional calculations and special blending mode. I agree, it can be done for N64 graphics plugins too, and with any API.
Now we need a volunteer

 

[Cyberman]

the 3d models thing is a bit hairy.
As Rice pointed out It depends on how the software (IE game) handled loading the model data.
Anything is possible, just you should ask yourself is it practical.
CoolisCool's thread in programming shows that it's possible to tweak data in a game (or view it) with a great deal of patience. Replacing the models has been a dream of many a gamer. I know on the playstation this is nothing short of a nightmare (because the GPU is 2d and all the 3d magic happens inside the playstation coprocessor the GTE).
If the game used a 'standard' library or microcode for the N64 coprocessor then it's practical. If not, not so practical.
Side note understanding why it's difficult to get 3d data in a consistant manner:
I remember having an arguement with one of the guys who made Wolfenstien 3d (they were working on Doom at the time though I didn't know it). He wanted to have full access to the hardware (I was designing a system I just said to hell with after this conversation). It was to have programmable hardware for flexible archetecture, and like any programmer he thought it insulting that there wouldn't be full access to programming the hardware.
What has this to do with changing models? If there is no standard method to do things, it makes doing model insertion VERY difficult, because EVERY game will use a different set of procedures and functions to do this.

Cel shapding in the graphic plugin itself might be a good way of doing it. Although I'm not sure how one determines what to cell shade and what not to. Perhaps just shading anything with textures might work.

Cyb

 

[mdtauk]

2d Sprite textures, like the HUD or the flat trees in Mario 64 shouldn't be cel-shaded, but the environments and charcters yes.

 

[Driscol]

even if we do get this working, the whole thing is just a lighting effect, right? ao it also depends upon the geometry of the model. if links face is a triangle based model, then his face could be a gradient of triangles, which would look crappy.

 

[M[u]ddy]

even if we do get this working, the whole thing is just a lighting effect, right? ao it also depends upon the geometry of the model. if links face is a triangle based model, then his face could be a gradient of triangles, which would look crappy.

Have you ever seen the screenshots of Orkins beta plugin?

 

[mdtauk]

 

[Rice]

I am not 100% sure, but I think there are still problems in Orkin's implementation on this screenshot. The hat is lighted on both bottom-right and top-left. This may be caused by more than 1 lighting. I think it could be better than this. And there is no highlighted edges. Maybe we don't really need to draw the edges.

 

[Elite Knight]

Hey rice long time no see from you hope you might start up your plugin again not that mudlord isent bad at it hes just been quiet for a while now. Ok back on the topic try those files that guy posted they worked good with your pack some things might need adjusting but hey still looked good. Also rice i need to ask you somthing about your texture dumping pm me or pm me for your msn if you have one because i cant seem to get somthing right.

I think it's a bit off i'v seen Zelda WW and it's cel shader is configed right mabey this plugin might need some tweeking. Ok i hope i said every thing right. Peace

 

[Rice]

Elite Knight, I haven't touched the plugin source code for more than 2 years. I don't know if I can help you on the texture dumping. You can pm me your question.

 

[mdtauk]

The background should really have no shading at all, or if it does, only two tones, certainly not as strong as the character's shading. Also the top light is coming from Navi, she is a light source you know

 

[mdtauk]