The Sinclair QL Forum

Hi Folks,

tofro wrote:
<< There's also the QPC_QLSCREMU -1 command that allows you to load QL screens even in arbitrary resolutions and colour depths - It simply emulates the QL screen in the top left of the QPC screen. >>

Yes, but I needed a routine to fill the whole screen, (in another program). I have now added a few code statements so the program (today post 10h49am) gets mode 4 colours right too. I may adapt it for different resolutions than the 512x256 QPC2 preset.

Thanks, Per, for the extra info in your listing, which will be very useful.

Regards,
Steve.

Hi Tofro,

To get a full QL screen on QPC2 :

1 : Click on your QPC icon to load it.
2 : In the 'resolution boxes', type in 512 and 256.
3 : Hit OK.
4 : Click on the 'full screen' rectangle, (top right of QPC window).
5 : Done ...

6 : Repeat item 4 to reduce the screen again !

Best Wishes,
Steve.

Hi All,

The QL to QPC2 screen transfer program is now finished, (in so much as are my requirements). Modes 4 and 8 are catered for.

There is no point in using SCR_XLIM or SCR_YLIM etc, as they return the size of the full QPC screen, irrespective of the actual size used.

I manipulate binary string$ instead of bitwise operators, as these are easier to prototype with... in basic !

So It easy to see how routines like RECOLOR could be written, so feel free to tweak as you wish.

Regards, Steve.

100 :
110 REMark zzMIX - Transfers SBYTEd QL screens to QPC2 via LBYTES.
120 REMark QPC2 screen resolution is 512x256, & 'full_screen' rectangle clicked.
130 :
140 WINDOW 512,256,0,0: OVER 0: PAPER 0: INK 7
150 s1=SCR_BASE: s2=ALCHP(32768): s3=ALCHP(32768)
160 LBYTES dos5_globe_pic,s3 : REMark Or whatever names you gave your files.
170 LBYTES dos5_spiral_pic,s2 : REMark Or whatever device you are using.
180 REMark demo to show mode 4 (and mode 8) treatments...
190 CLS: swapem s3,8: swapem s3,4: swapem s2,8: swapem s2,4
200 PAUSE 500: CLCHP: STOP
210 :
220 DEFine PROCedure swapem(ad,md)
230 st=1: IF md=8: st=2: REMark ad is address, md is MODE.
240 x=0: y=0: FOR f=0 TO 32766 STEP 2
250 REMark lookup pixel Words as binary :-
260 greens=PEEK(ad+f): reds=PEEK(ad+f+1)
270 green$=BIN$(greens,8): red$=BIN$(reds,8)
280 REMark Mask out the flash bits :-
290 IF md=8: FOR j=2 TO 8 STEP 2: green$(j)='9'
300 REMark find each binary pixel colour :-
310 pos=0: FOR bit=1 TO 8-(md=8) STEP st
320 IF md=4: pix$=green$(bit) & red$(bit): px=pix$
330 IF md=8: pix$=green$(bit) & red$(bit) & red$(bit+1): px=pix$
340 REMark Don't select on string variable$ :-
350 SELect px
360 =0 : ik= 0
370 =1 : ik= 1: IF md=4: ik=2
380 =10 : ik= 2: IF md=4: ik=4
390 =11 : ik= 3: IF md=4: ik=7
400 =100: ik= 1
410 =101: ik= 2
420 =110: ik= 3
430 =111: ik= 7
440 END SELect : REMark pos=position in byte , ik=INK , st=pixel width (step).
450 BLOCK st,1,x+pos,y,ik: pos=pos+st
460 END FOR bit
470 x=x+8: IF x>511: x=0: y=y+1
480 END FOR f
490 END DEFine
500 ::

Hi Steve,
Nice work I may not have understood you properly, but it appears to me that there is an issue with mode 8. If I take a mode 8 QL screen dump it doesnt appear to display correctly in your mode 8 recreation. For example, yellow gets lost in translation.

Hi per,

Yes, I have done a fix for this problem, in as much as I now get 256 colours.

But that still leaves a problem wuth QL stipples : If I tweak for these, the mode 4 then mode 8 screens are often offset by 1 pixel !

I will report back as soon as I understand the reason for this.....

Many thanks,

Steve.

Hi per,

The program now appears to be correct with all QL and QPC2 MODE combinations.
Graphics ouput is OK with QPC2v3.31, but one pixel wrong with QPC2v4.02 !
I have tried pictures saved with and without SGC...
Regards,
Steve.
____________________
100 REMark zzSWAP
110 WINDOW 512,256,0,0: OVER 0: PAPER 0: INK 7: BORDER 0: CSIZE 3,1: CLS
120 s2=ALCHP(32768): s3=ALCHP(32768): LBYTES dos5_yourpic1,s2: LBYTES dos5_yourpic2,s3
130 FOR QPCmodes=4,8: MODE modes: swapem s2,QPCmodes,4: swapem s3,QPCmodes,8
140 CLCHP: INK 7: CSIZE 0,0: STOP
150 :
160 DEFine PROCedure swapem(ad,md,qm)
170 st=1: x=0: y=0: AT 7,1: PRINT 'ql MODE'!qm,'qpc MODE'!md
180 FOR byte=ad TO ad+32765 STEP 2
190 greens=PEEK(byte) : reds=PEEK(byte+1)
200 green$=BIN$(greens,8): red$=BIN$(reds,8): pos=0
210 IF md=4 THEN
220 FOR bit=1 TO 7 STEP 2
230 pix$= green$(bit) & red$(bit): px=pix$
240 SELect px: =0:ik= 0: =1:ik= 2: =10:ik= 4: =11:ik= 7
250 BLOCK 2,1,x+pos,y,ik: pos=pos+2
260 END FOR bit
270 ELSE
280 FOR bit=1 TO 7 STEP 2
290 pix$= green$(bit) & red$(bit) & red$(bit+1): ik=BIN(pix$)
300 BLOCK 2,1,x+pos,y,ik: pos=pos+2
310 END FOR bit
320 END IF : x=x+8: IF x>511: x=0: y=y+1
330 END FOR byte
340 END DEFine