If I understand you correctly you mean a grid of tiles each having their own X,Y co-ords?
If so i would suggest using a POO (Point Of Origin
) and having all your tiles run from that grid co-ord. That way you only ever have to adjust one set of co-ords and all the other tiles will adjust themselves accordingly. This will work in all four directions.
To scroll a screen, always draw everything first, and use the SYNC command afterwards, and only allow a set degree of movement between each SYNC to enable a smooth scroll.
So to summarise:
To set up your tiles:
DIM screenposX(10) : DIM screenposY(10) ;Co-ords (these will be relative to the DATUM co-ords.
DIM screenbmp(10,10) ;This line will contain what Bitmap is at co-ord X,Y
datumX=0 : datumY=0 ;DATUM co-ords
FOR L=1 TO 10:READ screenposX(L) : READ screenposY(L) : NEXT L
DATA 0,0
DATA 100,100
DATA 200,200
DATA 300,300
etc
SO------->
DO
FOR Y=1 TO 10:FOR X=1 TO 10
SPRITE (X*Y),(datumX+screenposX(X)),(datumY+screenposY(Y)),screenBMP(X,Y):SHOW SPRITE (X*Y)
NEXT X:NEXT Y
SYNC
LOOP
Ok, so now your screen is drawn.
If you are using Keys to scroll the screen, only alter the datumX and datumY values accordingly and then redraw the screen using the procedure above.
If you are experiancing a slow down due to the number of sprites being drawn, then use the SET SPRITE ?,0,0 command for all background sprites. This will turn the Backsave and Transparency Options off and significantly improve your speed.
Hope this is of use and I haven't been asking to suck eggs!
