On 13/04/2018 17:46, Dilwyn Jones via Ql-Users wrote:
Thanks for your replies, most of which agree with my understanding
but, unfortunately, not with my recent experience. (Eg see my post on
the Forum for one example:
This agrees with my experience of sprites and PIC files from when I
was writing Q-Dock. Some unusual things can happen if the sprites
aren't long word padded.
Could someone please explain the rules to me regarding the padding of
graphics objects for the two main formats: Sprites and Pics/PSA?
I thought Id worked it all out, at least for some modes, but my rule-
book does not appear to be complete, nor provide stable answers in
cases. Also, there are some formats Im not able to test.. So now Im
confused and would like to get a "definitive" take on the matter.
As I understand it,
Sprites must always be padded to Longs for all modes QL or GD2.
PIC/PSA must be padded for modes 4 & 8.
The GD2 modes 16 to 33 should/need not be padded and some viewers
may have problems if they are.
SQRview will detect excess padding and not show it.
I haven't much experience of PSA files, but since they are
essentially PIC files with an extra long word in the preamble, I
would assume they would handle exactly the same as PIC files after
taking the extra long word into account.
And that is the crux of the matter: Without a definitive description
its each to his own interpretation. This is bad for those of us trying
to produce fun or useful stuff. And the number of offerings out there
that dont really work, or work inconsistently, dont exactly evoke the
sense that "The QL" is a serious or relieable machine. It certainly
puts me off at times (my own failings in this regard notwithstanding ;)
If those who "wrote the book" on these matters arent able/willing to
pipe up, then we'll have to waste some time R-ingTFBs and doing the
tests ourselves. I'll be back.
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