"Z80 Project Vs Amiga Boing" :)

This demo was done to test out two of the new features of the V3 Z80 project; the enhanced sprite controller and character mapped display mode. Click the pic on the right to play the video (2MB - divx .avi)

Technical details: The demo runs at 50 frames per second (naturally:) but my crumbly video capture card / camcorder combo would only allow me to do a 25 FPS avi. There's also no tearing in the original, the split you may see on the video rolling down the screen was caused by the camcorder being slightly out of sync with the TV.

Really technical details: The display is actually in character mapped mode. The blue ball is made of hardware sprites and the red one is actually "the background" (using a character set made of ball fragments) which is being shifted smoothly with hardware scrolling. The grid behind both balls is regenerated each frame (its all the same character:) to compensate for the scrolling. The edge characters of the red ball also have to be regenerated each frame to cleanly mask the ball against the "changing but stationary" grid. The scrolly message uses a similar scroll compensating method along with beam sync'd IRQs and colour bars. Phew!

The tune is originally from the C64 game Hawkeye. Here the Z80 project is playing an Amiga Protracker conversion which I converted to use synth instruments (again) with my sound editor - kinda full circle, no? :)