The Sinclair QL Forum

Hi Per, Thanks for all the technical details. I just downloaded the latest QPC2 onto a windows10 computer, and your program version (modified as you requested), runs and executes spectacularly ! The 'high colours' certainly improve on the 256 of my previous PC, but the rightmost section of screen do...

Hi Per, Your program EXecutes or RUNs fine on QPC2, until the call to 'alpha_blend' on line 654, where it halts with 'unknown procedure'. I see there is such a call on line 114 which gives no such error message. (There is also a call on line 692). For some reason the #0 buffer also gets clobbered, a...

Hi Folks, Here is a second version of the MANDALA-spirograph 'screen-saver' program. Colour, detail and transitions are greatly improved. Tested on QPC2. Ok on SGC with 'aspect' set to 1 for circles. Otherwise set aspect (ratio) to suit your emulator ! The program uses all factors of 360 degrees to ...

Hi TMD, As mentioned before, I have a very short epicyclic orbits program, which I have combined into your spirograph routine. The result produces MANDALA-type designs which could make a reasonably good screen-saver, if the PAUSE were set to say 250 units. I hope you like it.... Just extract and RUN...

Hi TMD, By slight modifications to just the 'spirograph' procedure loop, the program can be converted into a beautiful randomised repeating 'screen saver'. If you allow ink colours from 0 to 255, the effect can be quite spectacular too. Thank you again for your hard work ! Steve. ______________

Hi TMD, Nice conversion ! Don't worry! spiro_bas works ok under smsq/e and QPC2, with 8 colours. For correct aspect ratio, add h=h*0.76 onto line 3070, and that's it ! ( I have a much shorter demo program to draw tons of epicyclic constructions.) But spiro is very good for users to experiment with.....

Hi TMD, On some more recent QL systems, replace 131072 with SCR_BASE, as this keeps any shifts in the memory area located.... Also replace 32768 (bytes), with SCR_XLIM * SCR_YLIM Eg: 100 SBYTES flp1_filename, SCR_BASE, SCR_XLIM * SCR_YLIM On emulators, you may need to modify again to allow for resol...

Hi Folks, By 'grammar' I suspect you all mean syntax 'railway line' graphs, as defined for example in Jan Jones' handbook. This will allow however strange legal programs like the very short : 100 ELSE But try mixing lines of SELects with IFs and ELSEs in disorder, and you may find very unexpected th...

Hi Bwinkel, You can use use a specific name for the EXIT variable with a REPeat loop, if you wish. Indeed, REPeat under SMSQ/E can work without a loop variable ! (Loop variables were retained for backward compatibility). But the fact is that NEXT never increments REPeat counts, as it would using the...

Hi Bwinkel, On a QL, NEXT will increment in a FOR loop, but not in a REPeat loop. The QL uses NEXT in FOR loops to activate 'loop epilogues', but not in REPeat loops : 100 FOR loop=1 TO 5 110 PRINT loop !! 120 NEXT loop: REMark increments loop and falls through to epilogue on loop=5... 130 PRINT 'en...