| |
Codey
Registered: Oct 2005
Posts: 79 |
How Does ESCOS Work?
I always assumed ESCOS used the FLD trick to create perfect timing on each scan line, allowing sprites to move freely but not allowing characters to be drawn. Now, I'm pretty sure this isn't how it's done. Does it still use a combination of $D011 and $D016 to turn off all the borders? |
|
| |
JackAsser
Registered: Jun 2002
Posts: 1989 |
* You open the upper and lower border using $d011 but at the same time disable all badlines (chars). See this forum thread how this is done: Screen with no Badlines
* Then on each line you remove the sideborder using $d016.
* Then apply multiplexing of the sprites on lines where appropriate and/or stretch them using inc$d017/dec$d017.
|
| |
HCL
Registered: Feb 2003
Posts: 716 |
Exactly.. and to fill up the whole screen width, you have to expand the sprites with $d01d = #$ff.
The original ESCOS was also y-expanded with $d017 = #$ff, but no fancy stretch-stuff or fiddeling.. Only pure multiplexing by settnig new sprite y-position every now and then.. |
| |
Marauder/GSS
Account closed
Registered: Jul 2006
Posts: 224 |
and use $D018 to quickly change sprite-pointers, afair... |
| |
HCL
Registered: Feb 2003
Posts: 716 |
Quote: and use $D018 to quickly change sprite-pointers, afair...
Daaarn, there you spoiled all teh phun :(((. but well, that's in fact a good idea :). |
| |
JackAsser
Registered: Jun 2002
Posts: 1989 |
Quote: Daaarn, there you spoiled all teh phun :(((. but well, that's in fact a good idea :).
So Codey, you have the general algorithm, we expect results within a week. Or perhaps simply extract the nice ESCOS part in Totally Stoned II by HCL. =) If you like you may also steal my ESCOS part in the S:T Lars 2006 invite. Then if you are really lazy you can use that ESCOS generator that converts a bitmap to ESCOS and pack it with a viewer! :D |
| |
WVL
Registered: Mar 2002
Posts: 886 |
hurrah for lazyness :D |
| |
Mace
Registered: May 2002
Posts: 1799 |
I'm even more lazy and watch you guys do it. |
| |
MagerValp
Registered: Dec 2001
Posts: 1055 |
Or type in the source from Datormagazin :) That's what I based my all-border hires chess scroller on in Bunny...
|
| |
Bacchus
Registered: Jan 2002
Posts: 154 |
Mager
Was that my code or? Have a refer nice to the article?
/Bacchus |
| |
MagerValp
Registered: Dec 2001
Posts: 1055 |
You may or may not be surprised to learn that I don't quite remember which issue I was talking about in a forum post from 2008 referencing a demo part from 2003 based on a magazine article from the 1980s. |
... 2 posts hidden. Click here to view all posts....
|
| Previous - 1 | 2 - Next |
