Was doing some experimenting with the PCIN character mode (Graphics 12 + 10 interlace) and I had an idea ... it might be possible to do a port of Puzzle Bobble / Bust-a-Move (as it's called in Linux World) using this mode.
To start off, I've done a multi-character set unoptimized render of a MAME screen capture, along with a demo ATR ...
![puzzle bobble.png]()
MAME capture
![puzzle bobble test - pcin.png]()
![Attached File]()
puzzle bobble - pcin.atr 90.02K
27 downloads
This character mode allows for 35 colors onscreen, at Antic 4 (160 pixel) resolution. This mode works like Super IRG, except you are also changing the GTIA to reflect mode 10 every vblank, combined also with a display list shift, and a COLBAK (712) shift to ensure a stable background and enable an extra color register. The flicker (hopefully) is reduced, partially because of the fact that no color register changes are made ... areas of the screen where the PF0-PF3 colors mix, will be relatively stable and flicker free ... with antiflicker dithering possible to help out.
This screen is best viewed on a real Atari ... emulators tend to mess up the flicker really bad unless you use frame blending. Would be curious to see what results are gotten on the real machine.
This is a straight bitmap style render using 8 character sets ... so, a bit of work will be needed to get the screen to display using just one or two optimized character sets. It's likely the checkerboard background might need to be altered to better match up with the colored bubbles ... also remembering, in addition to the red, green, yellow, and blue bubbles, we will need three more colors (purple, grey, and black ... colors which are doable in this mode with these color settings). Each bubble will need 4 characters in order to display. It may be that 2 character sets would be needed for the game.
I'm going to also eliminate the scoring display at the top to enable the bottom two character rows to display. It's better to have a row of normal non interlaced character mode at the top (Antic 2 maybe) for the scoring display, as PCIN is not really suitable for readable text,
There will also be some experimentation to see if I can get PMG's to display here ... it's likely that PM0 will be unusable, so we'll be limited to three players ... four, if you use the fifth player option. Plus, these will have to be the same color as some of the mode graphics, as mode 10 also uses these registers.
The idea is, character sprites for the bubbles, and also for the arrow pointer ... you might need several frame captures, and a delta system to move the pointer. When this is optimized down, the overhead for this mode should be about 2K for the character set (4K, should a second character set be necessary), plus the normal overhead for an Antic 4 screen (960 bytes) ... plus however much you might need for PMG's should they be necessary.
To start off, I've done a multi-character set unoptimized render of a MAME screen capture, along with a demo ATR ...
MAME capture
puzzle bobble - pcin.atr 90.02K
27 downloadsThis character mode allows for 35 colors onscreen, at Antic 4 (160 pixel) resolution. This mode works like Super IRG, except you are also changing the GTIA to reflect mode 10 every vblank, combined also with a display list shift, and a COLBAK (712) shift to ensure a stable background and enable an extra color register. The flicker (hopefully) is reduced, partially because of the fact that no color register changes are made ... areas of the screen where the PF0-PF3 colors mix, will be relatively stable and flicker free ... with antiflicker dithering possible to help out.
This screen is best viewed on a real Atari ... emulators tend to mess up the flicker really bad unless you use frame blending. Would be curious to see what results are gotten on the real machine.
This is a straight bitmap style render using 8 character sets ... so, a bit of work will be needed to get the screen to display using just one or two optimized character sets. It's likely the checkerboard background might need to be altered to better match up with the colored bubbles ... also remembering, in addition to the red, green, yellow, and blue bubbles, we will need three more colors (purple, grey, and black ... colors which are doable in this mode with these color settings). Each bubble will need 4 characters in order to display. It may be that 2 character sets would be needed for the game.
I'm going to also eliminate the scoring display at the top to enable the bottom two character rows to display. It's better to have a row of normal non interlaced character mode at the top (Antic 2 maybe) for the scoring display, as PCIN is not really suitable for readable text,
There will also be some experimentation to see if I can get PMG's to display here ... it's likely that PM0 will be unusable, so we'll be limited to three players ... four, if you use the fifth player option. Plus, these will have to be the same color as some of the mode graphics, as mode 10 also uses these registers.
The idea is, character sprites for the bubbles, and also for the arrow pointer ... you might need several frame captures, and a delta system to move the pointer. When this is optimized down, the overhead for this mode should be about 2K for the character set (4K, should a second character set be necessary), plus the normal overhead for an Antic 4 screen (960 bytes) ... plus however much you might need for PMG's should they be necessary.