Dither and Animations

[Cyangmou]

Hello pixel fellows,

I came some time ago over the question if it's senseful to connect dither and animations. I am thinking about dither as method to smoothen out gradients while keeping the color amount low and to add a clean looking but raw texture to smaller sprites (stone, rusty metal). Dither can look great if it's done in the right doses because it strengthens the impression of volumes and it's also a easy way to achieve hard and soft edges.

The only thing which is bad about dither is that it works only with bigger clusters. So there is no way to use it for standard e.g. 32x32 animations. But if you have to animate a bigger sprite (64x64+) it can be that there will be enough space for dithering.
This leads me to two solutions:
a) I use more colors - modern hardware don't really has a limit so there will only occur heavy banding problems if I am using too much colors - (this means that I am keeping my color orchestra manageable)
b) I use dither

I heard that dither is in general bad for animations because there will always be some pixel fragments which look odd.

I have an dither example from metal Slug:


(don't mind that it's zoomed in - I was lazy and don't build rips together)

As you can see they used animated ditherpatterns. If you are looking at the elephant's back you'll notice that the dither there isn't moving heavily, it looks more crisp and clean than at the elephant's legs. I think the Dither at the hind leg leads to serious clusterfuck because the basic clusters changing there form heavily and the dither makes this impression even worse.

Because of that I'd say dither works at calm parts of an animation



An example for the layered method would be my seasnake:



The whole sprite uses only layered clusters without dither. The animation stays crisp and clean (at least at the head and the first body segments where I worked more carefully) but in general the form with a layered style looks more flat.


The Questions are now:

1) Dither
1-a) Is Dither from it's technical side a plus for pixel graphics or is one color more better?
1-b) Where does dither general improve a graphic?
1-c) Improves dither the 3D effect (or general form) of a graphic more than more layered clusters?

2) Dither + Animations
2-a) Is it possible to use dither and animations together or is it a NoGo?
2-b) if 3 is possible where are the best places to achieve a better result with dither?

Well, that's all to start with

[9_6]

Kind of like applying a filter to an image, dithering is destructive.

You can easily divide and then bucket-fill a shape where needed but if it's all single pixel clusters, all the work always has to be done manually and more work is the last thing you need while animating.
Rotating dithered parts of your sprite will also look even more terrible than if it is clean clusters so if you use that approach to animate (chances are that if you work large enough that dithering works, you may want that), dithering will be a pain yet again.

So I'd keep dithering and animation sepparate for purely practical reasons alone but I also don't find 50% dithering to look appealing enough to outweigh the pain it brings anyway.

[rikfuzz]

Hmm.. That kind of checkerboard dither is the smoothest 'mix' of two palette entries, so it can be used to add extra colours too smooth out large areas, but it still adds some grain, so it's used for texture sometimes too. 

From a technical standpoint, if I were to be animating something that had this kind of dithering (for whatever reason), I'd replace all the dithered areas with additional colours, animate it as normal, and then replace the additional colours with pattern fills in one go at the end. 

[Helm]

That elephant gains nothing from dithering in animation, though each frame on its own does gain. I'd solve this problem by not using dithering on sprites that have many, many frames of animation, for workflow purposes this just saves time. I do not think there are time-effective ways to keep the dithering for such super smooth animations. Moreover, I am not convinced that the dither pattern texture is something that's pleasing to the eye of non-pixel art affictionados that know why and how the dithering has come to exist. Whereas in still images, the effect can be seen as controlled much more easily and appreciated as artistic, in motion the untrained eye might think 'oh, this looks like a strange artifact of low-color reduction'.

[Ai]

1) Dither
1-a) Is Dither from it's technical side a plus for pixel graphics or is one color more better?

That's a style choice. I think of dither as airbrushing (and secondarily texture), so in general I would say it's associated with a more realistic, and perhaps more atmospheric, style.

1-b) Where does dither general improve a graphic?

Places where airbrushing would -- ie. where it makes sense to trade distinctness of shape for smoothness of shading.

1-c) Improves dither the 3D effect (or general form) of a graphic more than more layered clusters?

With regard to giving a more 3D effect,  I regard it more as a finishing technique which draws together clusters which are already well defined in 3d to make them -- more rounded, usually.  Personally I like the effect of layering a lot of clusters, but it's a lot of work, and easy to do badly. Dither is somewhat more forgiving, and has a bit more scope for implying texture, as long as you apply it thoughtfully.

2) Dither + Animations
2-a) Is it possible to use dither and animations together or is it a NoGo?

Yes, if you coordinate yourself carefully (and usually, use only 50% dither). See Vanguard Princess for an example of a game that successfully combines them (targeted to 640x480 resolution IIRC).
Dither+Animation is also used sparingly in a number of Genesis games.

However, there are some rather interesting issues that only come up when using dithering. In general it's certainly more demanding and finicky, so personally I would avoid it whereever possible. By which I mean although I'd be interested to use it, I don't have the time to spend on the extra tweaking necessary; Although I intended to be clear that it can be done well, I do agree with Helm that it's not actually worth doing.

[questseeker]

I like the animated dithering on the elephant a lot: it gives a sensation of moving texture that suggests shading changes due to small deformations (e.g. trunk), large-displacement deformations (e.g. the anatomically dubious one at the top of the back, between the character and the belt which don't actually move), drastic lighting changes (e.g. the frame in which the skin flap in front of the hind leg is distended and lighter).

[Cyangmou]

Thanks that all of you took time to help me with my thoughts. Most of the things you are pointing out are the things which I thought the exactly same way about it, and there are also some really interesting thoughts from you.