Though unrelated to the issue, why do you have such a large image made up of a small tileable image? Seems like a huge waste of memory.
I thought your movement code was the culprit. Your rotating the sprite to point in the direction you want to move, moving 'forward', then rotating back..... why? Especially for a background. So I changed the code like this: (much simpler movement code)
randomize timer()
set display mode 1920, 1080, 32, 1
sync on:sync rate 60
color backdrop rgb(0,0,128)
set text font "arial" : set text size 12 : set text transparent
load image "c:\testMap.png",1
sx = 300 : sy = 300 : speed = 4
sprite 1, sx, sy, 1 : hide sprite 1
do
rem W - up
if keystate(17) then inc sy, speed
rem S - down
if keystate(31) then dec sy, speed
rem A - left
if keystate(30) then inc sx, speed
rem D - right
if keystate(32) then dec sx, speed
rem show background
paste sprite 1, sx, sy
sync
LOOP
But that didn't help. I've tried different images, large and small. I still see it. And I don't recall seeing this on my own 2D projects.
But as was discussed in yet another one of your threads about this issue, I've changed the code above to add the vertical sync flag to the
set display mode command and that seems to have resolved the issue.
"You're not going crazy. You're going sane in a crazy world!" ~Tick
