QL Art

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BSJR
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Re: QL Art

Post by BSJR »

TMD2003 wrote:
BSJR wrote:Comparing the two images there appear five lines of rubbish at the start minus an offset of 32 pixels.
I guess some header info got translated as well, so conversion should start at +5x256 -32 pixels, in bytes for the Tiff.
That's what I'd assumed - but then I'd also assumed that the four values in the SELECT loop towards the end of the main procedure had been chosen to account for that.
I had to check the S*Basic Reference Manual for this unusual use of SCROLL & PAN in this _bas, acting as file pointers. That may not be valid for the ROM you are using. If TK2 is present this can be replaced with BGET #3,n.

BSJR


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TMD2003
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Re: QL Art

Post by TMD2003 »

BSJR wrote:I had to check the S*Basic Reference Manual for this unusual use of SCROLL & PAN in this _bas, acting as file pointers. That may not be valid for the ROM you are using. If TK2 is present this can be replaced with BGET #3,n.
I was wondering what was going on with those. I could see they were acting on the file (SCROLL #3 and PAN #3), but how that was made to work is well beyond me.

And to think that POKE_L 167722,base was considered "The Wild West"...


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dilwyn
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Re: QL Art

Post by dilwyn »

TMD2003 wrote:
BSJR wrote:I had to check the S*Basic Reference Manual for this unusual use of SCROLL & PAN in this _bas, acting as file pointers. That may not be valid for the ROM you are using. If TK2 is present this can be replaced with BGET #3,n.
I was wondering what was going on with those. I could see they were acting on the file (SCROLL #3 and PAN #3), but how that was made to work is well beyond me.

And to think that POKE_L 167722,base was considered "The Wild West"...
They are at least documented by Simon Goodwin in his ROM Bugs articles from QL World: http://www.dilwyn.me.uk/docs/basic/rombugs.pdf


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