Deathchase

What you have here is the Alpha 3 version of 3D Deathchase for the MSX.

Alpha 3 Notes

This release contains some tidying, some polish and is more along the lines of the vision for an MSX version.

• Improved missile by using multiple colored sprites.
• Fix for end of sector 'hang' whorizon-basedased enemies are on screen
• Fixed the distant biker colors so they match the nearer ones (and recolored all of the bikers so they don't look like Santa)
• Animated tank tracks
• Updated Helicopter gfx and animation
• Improved colors in debris animation.
• Improved debris effect
• Fixed debris sprites 'wrap around'.
• Missile sound effect no longer repeats if you hold down the fire button
• The tank colors are no longer very 'creative' (there were placeholder).
• Tank and Biker background explosion fixed so it no longer flashes with the border when you collide with a tree
• Wipe the bullet sprites when you crash.
• Helicopter was too fast
• The Helicopter blew up one line above what it should have.
• The Helicopter and Tank were appearing too frequently.

Known Issues

• There is a bug where if your missile collides with a biker after you crash, you get the kill...but I kinda like it.  Left it in for now.

Still to-do

• I'd like to replace the explosion graphics when they change to debris.
• Final tuning of tree density TreePopulationLookup table. 
• Throttle sound effects (this requires an audio re-write, so it'll be done after the full release).
• Surprises.

Alpha 2 Notes

• The big fix is for MSX1 - VDP timing corrects fix a lot of troubled graphics.
• I have slowed the bullet down so that the idea of 'steering' it is in line with the Spectrum version.
• Crashing during Night Patrol no longer has you restart in day time.
• Further tuned the tree density - the game is a little easier.
• There is no longer any choice between keyboard and joystick play - press space and you can just put your hands on the keyboard or the joystick.

MSX Improvements

• It has been optimized in terms of how it renders and I've taken advantage of that to present a game that is faster than the original ZX Spectrum version.
• Colored sprites.
• More audio effects have been added.

Why?

This was one of the first cassette games I purchase for the ZX Spectrum.  It's a classic for that computer.  The fact it is #1 on the Your Sinclair top 100 should inform you how people feel about this game.

I was fascinated by how such a playable title was put into a 16k game.  Having finally had time to look into that, what better way of paying homage to it than creating versions for new platforms.  I decided the MSX was first largely because I had never programmed for MSX prior and I felt I may be able to make slight improvements.

The MSX version is faster.  I originally developed a similar bitmap-based implementation but the game draws and overdraws quite a lot - for every 9 bytes of data (a character and its color) written to the screen on the Spectrum, required 16 bytes on MSX.  For the same CPU, same speed the MSX version was slower.  Therefore the only choice was to optimize it for MSX hardware and in doing so, I managed to keep all graphics intact AND still meet the original goal of a more colorful version.

What next?

As the Alpha issues are reported/fixed, this naturally has to go onto ColecoVision in some form or other.  I also want to put something onto Mattel Aquarius.  I'd also like to do a 6502 version.  Finally, the MSX bitmap version...while it was never finished I'd like to re-purpose that code for another bitmap-based format at some point.  Suggestions welcome.