C64 ASM: Skull Tumbler V1-4

C64 ASM: Skull Tumbler V1-4

Skull Tumbler v1-4 [2014]: Coding, GFX and Music by Wolfgang Bochar. This is a long time coming, I’ve managed to the IRQ timing correct, 16 sprite blockers to give the window effect and no jitters. Works on NTSC and PAL machines, though PAL is a little slower on the playback. I used to have closer to 18 rows of text graphics scrolling — but when combined with the audio, sprites and x-y scrolling in the two raster areas.. it got quite jittery. There is only so much raster time to render the image, so I started running frame 0 half image then frame 1 lower half — then the Y scrolling started to look jumpy with the timing. This version has a smaller window, but I like the simple layout better (but full screen video is great too). Something to work at in the future.

I am pretty happy with this, it is the cleanest and most complex IRQ coding I’ve every done. I’d like to thank the crew at Covert Bitops for the ASM Notes and GoatTracker (which I composed the music on), The KickAss Assembler and the Kick IDE guys (makes Dev so much faster), Oliver Achten and Jens Schönfeld for the MMC Replay (makes testing on a real C64 fast and easy) and Takeshi Yano (for all the C64 chats over the years).

The Source graphic (and any video data on this site) was generated by GIF2C64 (C# application), that takes gifs (animated too) and generates custom charsets. I haven’t got all the bugs out, but after alpha is finished I’ll post a beta version for external testing.

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