[stella] Star Fire - Return of the Starfield ?!?

[Manuel Polik <cybergoth@xxxxxxxx>]

Hi there!

Reaching the end of all my knowledge, I once more need 
your advice. :-)

Though it actually was impossible, I somehow managed to 
put the Starfield back into my kernel.

Well, attached is the result. It's not yet centered 100% 
and there's some flaws in the kernel, but:

You'll realize immediately, that it's not acceptable at 
all. The flicker is maddening, probably worse than 
SW-TAG.

I can tell you, why it must flicker that much. 
The reason is actually simple: Repositioning an object 
takes a whole scannline. This _can't_ take place in a 
line where I'm repositioning or drawing a sprite.

What you see now, is a compromise, where I can draw the 
stars only in the vertical gaps between the sprites. A 
huge sprite can occupy enough vertical space to blank 
out 5 stars at once for example.

Well, I don't think it makes any sense continuing with 
that approach. Even though I think it's a little better 
on the TV, I won't continue with that.

Now I'm thinking of alternatives. Does anybody have an 
idea?

Well, I could try for example doing 9 stars by utilizing 
both missiles and the ball and cycling through them with 
20Hz, but that'll flicker again, of course. A little 
less probably, but it'll flicker. Maybe like Star 
Raiders. I think Star Raiders does it that way. Is this 
acceptable?

Other ideas?

Phew... I think I should feel frustrated now... spending 
almost 8 hours for nothing. Yet another learning 
experience I think :-)

Greetings,
	Manuel

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