Made a new (!) Scoopex demo called 'Blitter Sweet'

[Chain]

wow, a fresh scroller

[Photon]

Originally Posted by Toni Wilen

Problem is very simple:

00039bfe: 0092 0080 ; DDFSTRT := 0x0080
00039c02: 0094 0088 ; DDFSTOP := 0x0088

DDFSTRT larger than sprite x-coordinate = sprite is hidden. (except if using AGA-only BRDSPRT feature)

(DDFSTOP does not matter, sprites are visible from DDFSTRT to end of line. This is undocumented feature, logically it should be DDFSTRT to DDFSTOP but it isn't)

Yep. It was added in an optimizing frenzy to save bpl dma cycles Even so, WinUAE (1.3.2?) showed the sprites, and so being new to Amiga coding again I thought it was ok.

Progress so far - Modified the copper to fix the above, fixed some other stuff, fixing the $yydf,$fffe ugly coppershade 'steps' in the right margin, left to do - optimizing to fit it all into 1 frame now that there is more dma slots taken and 0x0 compatibility...

[Toni Wilen]

Originally Posted by Photon

Yep. It was added in an optimizing frenzy to save bpl dma cycles

Something like DDFSTRT=0x38, DDFSTOP=0x40 should work without causing missing sprites. (sprites are visible as long as DDFSTRT is earlier than sprite, DDFSTOP does not matter)

[Photon]

I was unsure if it was compatible with AGA, but I will do that, should shave a little more time... Removed 4 blits and optimized 1 raster line, still have to optimize some more to fix the stutter. Hopefully this will clean up the code somewhat, it stings my eyes now... always a good thing

Too bad my own playroutine is still half-finished... it would have fixed all this in an instant... give me time, will pay with PayPal. :P