I seem to have a problem with DRAWLINE not being able to draw to a sprite created with CREATESCREEN. The DRAWRECT does work. So I am wondering if this a bug, or am I doing something wrong?
Code with the problem
// Screen 0, Sprite 13
CREATESCREEN 0, 13, 256, 256
// Use screen for all output
USESCREEN 0
PRINT "Offscreen", 0,0
ALPHAMODE 0.8
DRAWRECT 254,0,5, 256, RGB(0,250,0) // <<---- This works
DRAWLINE 256,256,512,256, RGB(0,250,0) // <<---- Does not work
// Switch back to the window
USESCREEN -1
// Draw the screen
DRAWSPRITE 13, 0, 0
SHOWSCREEN
MOUSEWAIT
This is very humiliating. I had scratched my head for a long time on this one, and it is really such a silly mistake on my part. I had dimensioned the Createscreen to 256x256 instead of 512x512. So Drawline can obviously not draw to an area that does not exist. My Bad.
Yes, you are drawing the line outside the sprite you created. Your sprite size is 256x256, and the valid coordinates are 0 to 255 for X and the same for the Y. Programming is a fight with this little errors and you don't notice in first time. Happy coding.
Haha. Yes it is sometimes embarrassing to make such mistakes, but its part of the process of learning. I'll get there eventually.