User talk:Gruvinnz

ReGIS
Aren't the coordinates in that example wrong? If we want to draw a rectangle I would think it should be

V(B),[+100,+0],[+0,-10],[-100,+0],(E)

or perhaps

V(B),[+0,-10],[+100,+0],[+0,+10],(E)

As it is I think it draws a long horizontal line, then a short vertical line, then retraces those two lines. Jeh (talk) 05:12, 9 May 2015 (UTC)


 * You're right. I didn't even look at the co-ordinates themselves. I've updated the text. Thanks. Gruvinnz (talk) 23:17, 9 May 2015 (UTC)


 * Thanks. An "inertia trap" prevented me from firing up the machine where I could have tested it (a VS3100/76; probably hasn't been powered on in over a year...) and I didn't want to just make the change without at least another pair of eyes. Jeh (talk) 09:51, 10 May 2015 (UTC)


 * I tested it under Xterm. Image here
 * Xterm is by no means the real thing (not a DEC terminal). But I am confident that it's emulation is accurate enough for this test. ;-)
 * The rectangle in question is displayed overlapping the blue box, in the middle. (Second last line in the BASIC code)
 * FWIW, I used a Maximite Colour BASIC micro, over a USB serial link. Gruvinnz (talk) 21:37, 10 May 2015 (UTC)
 * Oh -- I probably should have mentioned that the above test was done in VT340 mode -- and perhaps that one has to compile their own version of Xterm, with configure --enable-regis-graphics ... and that it's quite some feat to get Xterm to communicate directly with a serial port -- without using screen under a unix shell, which filters escape sequences, wrecking the above results. But that's all quite another story. Gruvinnz (talk) 21:50, 10 May 2015 (UTC)