[Coco] Mary's arcade game nearing release

Roger Taylor operator at coco3.com
Sun Jan 6 01:41:18 EST 2008

With several days of dealing with collision detection problems after 
altering some code, I finally got it right tonight and the critter 
sprites are now reacting as they should when Mary's character touches them.

An extra VSYNC has to be used in the screen updates or the game would 
be too fast.  Now it runs at the ideal smooth and constant 
framerate.  Keep in mind that this game uses NO page flipping.  A 
single screen is used and all sprites are erased, moved, and 
replotted at the right time to eliminate flicker.  Special methods 
are used to minimize time-wasting opcodes in between the erasing and 
replotting.  I could probably add a lot more sprites to the game and 
have it work well, but I'l save that for my next idea.  Even the tree 
graphics are plotted on each frame (without erasing them first).  So, 
two VSYNCs are used to plot two groups of sprites, then a third VSYNC 
to slow the rate down to be just right.

I'll need somebody to test this game on a real CoCo 3 in a few 
days.  That version will have the tester's name encrypted in the code 
and displayed in the title screen.  The purpose of this test is 
mainly to see if there is any flicker on the real hardware.  With the 
way I have set the game to SYNC with the rising edge of the 60hz 
flag, it should be fine, but I want to make sure.

I may be able to sneak in a few extra features before releasing the 
game, but it depends on what they are.  Sling an idea my way and 
we'll see, but I want to get this game DONE now.

Also... the Super CoCo Archive DVD orders are still being processed 
after several weeks of a delay due to my job robbing me of at least 
12 hours a day and depriving me of any sleep over 3 hours a night 
during the UPS Xmas/New Years season.  Bad weather up North caused 
major problems with backflow at our center down South and this 
reflected in a major way on my web site duties.  Things are calm now 
and I'm putting in some hours at the keyboard and DVD burner.

If you ordered a DVD, I know about it and yours will be delivered in 
turn, and a groups of DVDs will go out each day until I complete the orders.

If you need to ask a question about any of this, please write me 
privately at operator at coco3.com and I'll try to estimate your delivery date.

Thanks, and Happy CoCoing.

More information about the Coco mailing list