AuthorTopic: [WIP][Nudity] AA help please?  (Read 4023 times)

Offline SafetyPinKisses

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[WIP][Nudity] AA help please?

on: May 14, 2009, 12:56:34 am
Alright well I'm part of Glam! and we're currently doing a redoll thing where we are assigned someone elses doll to redo while making changes to it. I've started on mine but I know a few things are off and I'd like to try and AA this one but I have no idea where to even start. I've tried looking up tutorials on it but they're all kinda confusing to me. I'd love it if someone could give me some pointers on how to do the AAing correctly, or somewhat correctly at least. (ignore the ugly looking colors on her pants I'm just starting to work on coloring those)



Base from pixel.ryoshi
Original dolls (on right) by Stino
« Last Edit: May 14, 2009, 01:47:43 am by SafetyPinKisses »

Offline Tourist

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Re: [WIP][Nudity] AA help please?

Reply #1 on: May 15, 2009, 10:03:09 pm
Thanks for the links.  It's always nice to see what other pixel artists are doing.

I've been wrestling with AA recently too.  Here's what I've learned.

First up, do any AA work LAST.  If you tweak your other colors at all you will have to redo the AA pixels and it is tiresome.

When to use AA?
AA has trade-offs.  On the one hand, it reduces the jaggies and smooths the curves.  On the other hand, it blurs your image and effectively reduces the resolution.  There doesn't seem to be any good rule of thumb for when to use it or not, but

1) You probably don't need it on straight lines that don't have any jaggies to begin with.

2) Avoid AA on small sprites.  The smoothing is not worth the effective loss of resolution.


Which pixels to AA?

Hopefully the more experienced folks can expand in this.

AA is slow if you do it by hand.  So focus on areas where the pixels aren't already smooth, like where a line or color changes angle.  Jaggies can usually be fixed by working on the underlying lines instead of using AA (it's faster that way too), but some areas will still have too sharp curves or banding.

If your art is going to be a sprite or be put on different backgrounds, then only AA the inside edges of the sprite.  If the art is part of a piece with background and all, inside or outside is fine.


How to select the colors?

If you have a limited color set, then you have to be very selective about using colors only for AA.  I expect there are some tricks on how to choose colors that serve both as AA for two existing colors and as a color for other objects on the screen.  I haven't seen any tutorials or tricks like this though.

If you don't have a color limit, then the AA methods are a variation on blurring or blending.  I think most people try and judge it by eye, but I made a chart:



For a target pixel in the center (C), you blend with the surrounding colors.  I list three different weights for the blending.  They're based on different math for how to blend the pixels, but you can just use those numbers or use them as examples and make your own balance.

Hopefully this can help you get started.


Things I'm not sure about yet:
AA tends to smudge the picture, which should reduce the appearance of depth.  But AA is often used on edges, where the depth changes significantly.  These two effects should be in opposition, I'm not sure how they actually play together.

Tourist

Offline ptoing

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Re: [WIP][Nudity] AA help please?

Reply #2 on: May 15, 2009, 10:12:22 pm
Sorry Tourist, that is not aa, that is blurring pretty much.

Here is an image I did some time ago. It is not finished and I should try to actually DO finish it, but I think it might help. :)
There are no ugly colours, only ugly combinations of colours.

Offline Tourist

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Re: [WIP][Nudity] AA help please?

Reply #3 on: May 16, 2009, 12:51:06 am
Thanks for correcting me, and thanks for the diagram.

Tourist

Offline SafetyPinKisses

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Re: [WIP][Nudity] AA help please?

Reply #4 on: May 16, 2009, 03:25:02 pm
Thanks for the help guys it'll really help me when I'm done with this

Offline Scribblette

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Re: [WIP][Nudity] AA help please?

Reply #5 on: May 17, 2009, 11:17:44 pm
Ahhh! Thanks, Ptoing! Is that in a sticky somewhere? I'd been struggling to understand how folk knew it better and worked too much off the 'feel' of it (lots of editing and little satisfaction >_<)

I don't quite catch what the science and percentages are about though. Must be a thread on it here somewhere, search function time!
Now reading: Animator's Survival Kit, Drawing On The Right Side Of The Brain, Fun With A Pencil. No time to pixel!
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Offline Akira

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Re: [WIP][Nudity] AA help please?

Reply #6 on: May 18, 2009, 02:18:40 am
The colours (green, blue, red, purple) represent an 8x zoom pixel - a pixel created out of 64 smaller pixels. The number of white pixels in each 8x zoom pixel is the first value (green is 4px, blue is 19px, etc) and the percentage is generated from the number of white pixels (green is 4px, blue is 19px, etc) over the total (64px). This percentage then corresponds to a colour value. The 6% represented by the green colour is essentially 6% white. This 6% white is the AA colour that should be used in place of the green 8x zoom pixel.

I don't know how well I explained that...
thanks Dogmeat!

Offline ptoing

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Re: [WIP][Nudity] AA help please?

Reply #7 on: May 18, 2009, 02:31:31 am
Yes, that was correct Akira. I have not posted this image before, because it is not done and it also needs some explanation for certain things.
I hope I will get some time soonish to continue working on it. Enough derailing now tho.
There are no ugly colours, only ugly combinations of colours.