Log inRegister an accountBrowse CSDbHelp & documentationFacts & StatisticsThe forumsAvailable RSS-feeds on CSDbSupport CSDb Commodore 64 Scene Database
You are not logged in - nap
CSDb User Forums


Forums > C64 Coding > Generating dither-charset for 8x8-effects
2008-04-09 11:09
Shadow
Account closed

Registered: Apr 2002
Posts: 355
Generating dither-charset for 8x8-effects

OK, so apparently my 8x8-dither-charset (used in 407566) is 'horrible' :D

I found it on an old disk, so I can't recall exactly HOW I generated it, but I think it was something like this:

Place pixel of col 1 randomly, but as far from exisiting pixels as possible to avoid big 'blobs' of color forming.. Repeat until full of col1, then start placing pixels of col 2 etc.

So, what is a better algorithm?
2008-04-09 11:13
HCL

Registered: Feb 2003
Posts: 728
Well, that sounds good, but it doesn't look like that alg was used.. Don't know.
2008-04-09 11:15
HCL

Registered: Feb 2003
Posts: 728
My algorithm:

Load teh font editor 1x1.
Put beautiful pixel on good place.
loop:
Copy to next char.
Put another pixel which makes the char even more beautiful.
Goto loop until char is full.

That will do it :).
2008-04-09 11:26
JackAsser

Registered: Jun 2002
Posts: 2014
Quote: My algorithm:

Load teh font editor 1x1.
Put beautiful pixel on good place.
loop:
Copy to next char.
Put another pixel which makes the char even more beautiful.
Goto loop until char is full.

That will do it :).


My algorithm:

Rip the char set from Deus Ex.
2008-04-09 12:04
enthusi

Registered: May 2004
Posts: 677
there is a nice one in the cc65-plasma-example from groepaz btw.
Or you can abuse GIMP to generate greyscale-dithering.
Or check old articles on color-printing-with-mono-color-printers-by-multiple-prints.
Seen some theory on dithering there.
Or check GoDot for a very nice dither-charset in the option-menu!
i.e. here, but there are more:
http://users.aol.com/howtogodot/pix/histo.gif
2008-04-09 13:08
Dane

Registered: May 2002
Posts: 423
Quote: My algorithm:

Rip the char set from Deus Ex.


Beautifully pixeled by yours truly.
2008-04-09 13:56
chatGPZ

Registered: Dec 2001
Posts: 11386
Quote:

there is a nice one in the cc65-plasma-example from groepaz btw.

and i dont even remember wether i ripped it or if i was crazy enough to make it myself =P
2008-04-09 14:43
enthusi

Registered: May 2004
Posts: 677
it says "generating charset" or something like that.
So its either generated or live-ripped :)
2008-04-09 14:56
chatGPZ

Registered: Dec 2001
Posts: 11386
oh yes, you are right. there is a ghetto generator routine in C. *hides*
2008-04-09 15:27
yago

Registered: May 2002
Posts: 333
My Algorithm is the following:

Design a nice dithered 8x8 char, with e.g. 64 intensities

matrix:
.byte 1,12, 8, 3,21, 4,36,56
.byte ...

Now you loop from 0 to 63, and plot every pixel into a char where its below the intensity from the matrix.

I might put that up into codebase64 one day, its very small, simple and the outcome (how good the dithered chars are) only depends upon the initial matrix.

This generates hires-dithering, might be adjusted for multicolor-dithering, but I never needed them.

Edit: removed double entries from matrix :-)
2008-04-10 21:44
Shadow
Account closed

Registered: Apr 2002
Posts: 355
Nice algorithm yago! I adapted it to multicolor mode and was able to generate a dither-charset with a much more standard/evenly distributed dither pattern compared to mine.
I tried it on my 8x8 plasma, and while the dither itself is probably better, it actually makes the 8x8 blocks much more apparent.
So somehow the strange ("ugly" :D) charset I had generated before managed to hide the 8x8 better. Sometimes it pays off to do things the wrong way I guess! ;)
2008-04-11 06:49
HCL

Registered: Feb 2003
Posts: 728
F FF**k Fk.. Hey, this thread can not end like this!! Dark side can not win!
2008-04-11 21:15
Frantic

Registered: Mar 2003
Posts: 1648
What's the dark side? Doing it with a bad algo (rather than a good one) or doing it with an algo (rather than by hand)?

Man... I am SO confused. Please please.. help me.
2008-04-12 09:16
Steppe

Registered: Jan 2002
Posts: 1510
Shadow - just look at the handle! If he ain't from the dark side then who is? ;-)
RefreshSubscribe to this thread:

You need to be logged in to post in the forum.

Search the forum:
Search   for   in  
All times are CET.
Search CSDb
Advanced
Users Online
t0m3000/hf^boom!^ibx
psych
XmikeX
The Syndrom/TIA/Pret..
Jazzcat/Onslaught
Yogibear/Protovision
Knut Clausen/SHAPE/F..
psenough
Guests online: 133
Top Demos
1 Next Level  (9.7)
2 13:37  (9.7)
3 Mojo  (9.7)
4 Coma Light 13  (9.6)
5 Edge of Disgrace  (9.6)
6 What Is The Matrix 2  (9.6)
7 The Demo Coder  (9.6)
8 Uncensored  (9.6)
9 Comaland 100%  (9.6)
10 Wonderland XIV  (9.6)
Top onefile Demos
1 No Listen  (9.6)
2 Layers  (9.6)
3 Cubic Dream  (9.6)
4 Party Elk 2  (9.6)
5 Copper Booze  (9.6)
6 X-Mas Demo 2024  (9.5)
7 Dawnfall V1.1  (9.5)
8 Rainbow Connection  (9.5)
9 Onscreen 5k  (9.5)
10 Morph  (9.5)
Top Groups
1 Performers  (9.3)
2 Booze Design  (9.3)
3 Oxyron  (9.3)
4 Censor Design  (9.3)
5 Triad  (9.3)
Top Coders
1 Axis  (9.8)
2 Graham  (9.8)
3 Lft  (9.8)
4 Crossbow  (9.8)
5 HCL  (9.8)

Home - Disclaimer
Copyright © No Name 2001-2024
Page generated in: 0.063 sec.