The magazine of the Melbourne PC User Group Robots in stereo Ken Holmes

In November 1995, ROBOTS3D.LZH was put on the BBS and is not available for the link on this page. It was a version meant to be viewed with red/green goggles to see various animated stick-figure animals(?) in stereo. As it was essentially a C++ programming exercise (to keep me off the streets), it was placed in the programming file area. I don't know how many of the 100-odd downloaders were interested in the C++ code included with the .EXE file, but hope they found running the latter to be fun.

This version is meant for use with the old mirror trick. It allows the robots to be colour coded and have black shadows, on a ground plane, which serves to define it without needing to draw "scenery" on it. They are still wire frame models making no claims to realism, but they are mesmerising and you can control their modes of activity, so they do seem to acquire a modicum of personality. ROBOTSMIR.LZH is now available for download as it contains only the .EXE file and a text file you can print out, to help with the keystrokes to get the most out of the program. The C++ code differs mainly in the calculations for the display; anyone interested in it is welcome to contact me.

Dramatis personae

By using Class objects in C++, we may have as many clones as we wish, but have settled for eight Robobugs, eight Robobats and four Robopedes. As you may note, the Robobug is a six-legged, camel-like insect of ungainly gait and peculiar habits, plodding doggedly around a circuit of eight targets - until you interrupt him/her/it. You can make any of them do a double shuffle, reverse, divert to a different target or circle around a single target. The 20-legged Robopede (twentipede) has a sinusoidally undulating motion on rippling legs and is content to crawl around a circuit of the targets or, alternately, vainly try to follow one of the Robobugs. Both will find their way through the gaps between the row of square obstacles.

The fundamental method of control is to nominate the target for each animal; this may be either a fixed target or a moving one, i.e. another animal. As they approach a fixed target, they are switched to the next one around the circuit. Now we come to the stars of the show, the Robobats, da-daah; they can be switched to 14 different modes of activity. They will happily cruise the circuit, swooping down on each target and climbing to cruising altitude in between. When a Robobug is allotted as a target for a Robobat, it is constantly hassled by swooping attacks and tight circling returns. If two, three or four bats are targeted on each other in an endless loop, they settle down to a stable circle - which can be distorted by varying the speeds of individuals. If the leading bat is given a fixed target on the ground, it will circle it and the others will fall in neatly behind in echelon formation - rather unconventional behaviour for bats, you will agree. By targeting all followers directly onto the leader, with various speed control and lateral displacement regimes, we can get formation flying in Vee, diamond, broad arrow and Y (sharp arrow).

With variations

The action may be seen from two different viewpoints

• a fixed point whence all may be seen
• a point above and behind the leading bat; a single key toggles between these at any time.

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