English Amiga Board - View Single Post

chb · 31 May 2018, 22:57

I'm not completely sure what you want to gain by this technique. For a color change every 8 pixels you can not use more than 16 colors, so max 4 bitplanes. Also you need to change color 4 for every line - the Amiga has no per-char-attributes like Sinclair/C64. You can use copper loops to have a shorter copper list, but DMA will be the same - so all slots during display are used for copper and display, nothing left for blitter and cpu.

So why not use 32 or 64 colors from the start? Less dma, more colors (in 64 mode), no attribute clashes. I do not see any benefit for your idea.

What could work: if you have unused sprites, you can use them behind the playfield to color your bobs (color 0 in the bob will be replaced by sprite color). You have only 16 pix width, but maybe it's enough for some clever coloring of some bobs.

31 May 2018, 22:57	#4
chb Registered User Join Date: Dec 2014 Location: germany Posts: 439	I'm not completely sure what you want to gain by this technique. For a color change every 8 pixels you can not use more than 16 colors, so max 4 bitplanes. Also you need to change color 4 for every line - the Amiga has no per-char-attributes like Sinclair/C64. You can use copper loops to have a shorter copper list, but DMA will be the same - so all slots during display are used for copper and display, nothing left for blitter and cpu. So why not use 32 or 64 colors from the start? Less dma, more colors (in 64 mode), no attribute clashes. I do not see any benefit for your idea. What could work: if you have unused sprites, you can use them behind the playfield to color your bobs (color 0 in the bob will be replaced by sprite color). You have only 16 pix width, but maybe it's enough for some clever coloring of some bobs.