Saturday 1 October 2016

Miniature Golf by Mitch Voth



Thanks to the help of Darren and jdiffendaffer on the MC-10 Yahoo group I was able to figure out the esoteric features of SG6 graphics mode to port a miniature golf game by Mitch Voth (Softside Magazine, Vol 6, no. 7) for the 16K TRS-80. I used Greg Dionne's M/L USR utility (a BASIC subroutine that pokes a USR "SET" function into memory for setting SG6 64X48 graphic points on the screen). I had to figure out a way to do without a point function by simply looking if the byte location of the screen map changed after plotting (i.e. no change means the point is already lit in that byte region). My conversation with Darren and J.D. did help me figure out how to reset a point, which allowed me to get a nice cursor flash function built into my port. Darren figured out a M/L USR "POINT" function (which can also be poked into memory), which I hope to use in future projects or possibly to improve some existing games. I've added that routine (HIRES_SET&RESET2.TXT) to the UTILS directory of my Github site.

Thanks again to all these folks for their help in my programming projects.

As can be seen in the pictures above I used my SG6 Basic text plotting routine to print the 3 message lines at the top of the TRS-80 original. Of course I had to condense the information to just the course #, par # and player's name (limited to 5 characters). Luckily the original game already doubled the pixels to draw the maps and ball on the 128X48 screen of the TRS-80, so representing it on 64X48 screen was no problem. I just had to half the pixel plot values and remove the second pixel plot done for all the SET commands in the original program. The original also used a period character for target for each hole. I used a red dot instead, and therefore had to re-program a different piece of code to judge when a ball enters the hole.

I have also made a couple of little fixes to my programs lately. My son Charlie left for Dalhousie University so his bedroom in the basement has been reverting (somewhat) back to my MC-10 "man cave." I also made a number of Retrocomputing presentations at our local Cape Breton CaperCon gamer and sci-fi convention. As part of that project, I got an old android tablet to work as a WAV file player for my real MC-10s to replace my tape cassette player. So I have been playing a lot of my games on the real hardware lately. I noticed that I hadn't properly entered the map data for the last map of my port of Robot R-29.  I also noted a misspelling in my port of Lance Micklus' version of the classic Star Trek III game. His version is very rich and complex. Here's a link to a video of my port from the TRS-80 of TREKIII:




And here's a video of my version of Miniature Golf (Note: I have added a few speedups since this video was made):




Thanks to John and Neil for mentioning my Robot R-29 project in their last Coco crew retro podcast. They gave me a little good-natured ribbing about being a Basic programmer but I still highly recommend their podcast for people interested in all things TRS-80. We Basic programmers are used to hearing such sentiments from the M/L and higher level language master race;)



Next post (hopefully) a Retrochallenge project of some sort.

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