As I was reading the sample code, I noticed you use ball for both the type and the type variable instance. While Blitz can distinguish between them, no problemo, human eyes are not as discerning,. Maybe you could rename the type declaration as T-Ball ("t" for type) for human readability, as follows:
Type T-Ball
Field Entity
Field x# , y# , z#
Field xs# , ys# , zs#
End Type
The memory access error is telling you the variable or object being accessed doesn't exist. It often occurs, for instance, when someone tries to use a graphic image that they did not successfully load (i.e. a "tree" image is un-successfully NOT loaded, and then the program tries to draw the tree.)
Type T-Ball
Field Entity
Field x# , y# , z#
Field xs# , ys# , zs#
End Type
The memory access error is telling you the variable or object being accessed doesn't exist. It often occurs, for instance, when someone tries to use a graphic image that they did not successfully load (i.e. a "tree" image is un-successfully NOT loaded, and then the program tries to draw the tree.)