So I just recently learned BASIC and figured I would try making a clone of pong on my own in darkBASIC pro, and I made everything else work just fine except for the part that makes the ball bounce off the paddle. And yes I'm aware that the game is not yet finished. The error is on lines 39-51 EVERYTHING IS 2D. /////////////////////////////////////////////////////////// // // Project: Pong // Created: Friday, August 31, 2012 // Code: Brandon Spaulding // Art: Brandon Spaulding // Made in CIS lab at CPAVTS // Pong art and code © Brandon Spaulding 2012-2013 // ////////////////////////////////////////////////////////// y=150 x=0 ay=150 ax=612 ballx=300 bally=200 ballx_DIR=1 bally_DIR=1 hide mouse set global collision on //objectnumber=10 //make object box objectnumber,5,150,0 do load image "media\paddle1.png",1 load image "media\paddle2.png",2 load image "media\ball.png",3 sprite 1,x,y,1 sprite 2,ax,ay,2 sprite 3,ballx,bally,3 if upkey()=1 then y = y - 4 if downkey()=1 then y = y + 4 //num_1 = sprite collision(1,0) //num_2 = sprite collision(2,0) num_3 = sprite collision(3,0) for t=1 to 2 //ball&paddle collision if num_3 > 0 if bally_DIR=1 bally_DIR=0 else bally_DIR=1 endif if ballx_DIR=0 ballx_DIR=1 else ballx_DIR=0 endif endif //if bally > 1 and bally < 500 then bally=bally + 2.5 if bally_DIR=1 bally=bally-2.5 if bally<-2.5 bally_DIR=0 endif else bally=bally+2.5 if bally>452.5 bally_DIR=1 endif endif if ballx_DIR=1 ballx=ballx-2.5 if ballx<-2.5 ballx_DIR=0 endif else ballx=ballx+2.5 if ballx>612 ballx_DIR=1 endif endif //bally = bally + t //if bally < 600 or bally > 1 then bally = bally - 2.5 //if ballx < 400 or ballx > 1 then ballx = ballx + 2.5 //move sprite 3,1 next t if escapekey()=1 then exit loop end Thank you in advance for the help.