4 replies to this topic

[José Pereira]

Hello.
Anyone here first can say something about how it can be done something like two Scrolls on A8 (like a 2nd Blue/Red,... on Turrican, R-Type,...)?
And if it is possible Backgr.,PF1,PF2 Ground colours, PF0 (Backgr. colour (some masking Sprites) and than use PF3 for that other colour/2nd Scroller/Backstage Pixels?


Moving the Ground with PF2 and second Scroll (with PF3) can be done 2scrolls without clashes?


This is the only way I see to get at least 5colours on A8:
3 for the Ground.
1 for the Backstage Gfxs. Pixels.
1 as Black.










But now the crazy idea:
ANTIC4or5 CharModes.
4/5colours on the Graphics and ex. Charset0 with Horiz./Vert. Scrolling Enabled.


Another Charset also with Scrolling enabled 4/5colours to the other Scrolling.



This will be like that NewBreed 2Charsets to get more colours. This 2nd with probably only Black(same in the other Charset) and Blue,Red,Yellow,... as PF3 the only that Flicker, probably not much (same Lumin. (nºs.6,)...

And they have to scroll but with different speeds, starting point of Scrolling...?




Crazy (also bad english...)?

Hope you understand and at least can explain how (in a normal way) get Paralax in an A8 Char Mode (also possible and not PF2/PF3 clash...).


Thanks.
Greetings.
José Pereira.

[TMR]

José Pereira, on Tue May 4, 2010 6:48 AM, said:

Hello.
Anyone here first can say something about how it can be done something like two Scrolls on A8 (like a 2nd Blue/Red,... on Turrican, R-Type,...)?

The more basic version of the effect is just a matter of having say a 2x2 character block that's repeated over the entire background the character definitions are scrolled in memory so they're moving the opposite direction to the scrolling and it produces some parallax - Lowca does that on the A8 already in fact, using a 2x1 character area if memory serves.

The only problem is refresh speed, if the scroller is shifting at one colour clock every other frame (like Humanoid or Zybex do if memory serves) the best bet is to have the parallax move every time the scrolling does so it remains static as the background appears to roll over it. Trying to roll it back every other refresh to get it moving slower than the foreground rather than remaining static will have a very distinct "wobble" to the movement.

José Pereira, on Tue May 4, 2010 6:48 AM, said:

And if it is possible Backgr.,PF1,PF2 Ground colours, PF0 (Backgr. colour (some masking Sprites) and than use PF3 for that other colour/2nd Scroller/Backstage Pixels?

In theory yes, in practise it depends on the graphics and where the software sprites need to move as to which colours can be used where. Me personally, i'd use one of the shared playfield colours for the parallax (probably a darker one just so that it doesn't become too prominent compared to the foreground stuff) so that it doesn't matter too much what the software sprites are trying to draw in over it.

[Heaven/TQA]

have a look...

http://atari.fandal....p?files_id=5313

http://atari.fandal....p?files_id=2140

[TMR]

There are a few more examples out there yeah, Warhawk has a bit of parallax (the grids behind some of the landscapes) f'example. i expect vertical is a tad easier to get looking decent than horizontal because it's got a finer scroll resolution...

[Heaven/TQA]

I did my parallax demo with flipping 4 fonts... it uses a lot of chars for the background and I am pasting the foreground layer over the background.

Jump and my Boinxx are using "char rotation" for the parallax fx which is far easier than the my horizontal demo.