:0->Xmin These 4 lines set up the window
:94->Xmax -
:1->Ymin -
:63->Ymax -
:PlotsOff Turns off your plots, so it won't graph plots during the game
:CoordOff Turns off the coordinate display
:AxesOff Turns off the Axis
:GridOff Turns off all the grid dots
:FnOff Turns off the 'Y=' functions
:Lbl A Label A
:0->B B takes the value 0
:randInt(10,85)->C C is now a random intiger between 10 and 85 (target's position)
:ClrDraw Clear any marks on the graph screen
:ClrHome Clear the home screen
:Line(C,1,C+5,1 Draw a line between 2 points : Line(X1,Y1,X2,Y2)
:Line(C+1,2,C+4,2 I think these Line()'s draws the target
:For(A,1,500) For loop, used as a time delay here. Using this as a time delay is considered bad
:End programming, because the For loop delay depends on processor speed.
:Lbl B Label B
:ClrDraw Clear the graph screen again
:Input "SHOT POWER=",S Prompts the user for the value of 'S'
:B+1->B Increases B by 1, used to count number of shots
:(1/S)->S Invert the variable S
:Line(C,1,C+5,1 Draw the target again
:Line(C+1,2,C+4,2 -
:For(X,0,95,.25 This For loop draws your shot path one point at a time.
:(-S(X^2)+63)->Y Makes a Y= function to plot an arc
:Y->Z Makes a backup of variable Y (the TI-83 will sometimes forget this variable when drawn)
:Pt-On(X,Y) Fills in a pixel at (X,Y). After here, the variable Y is as good as dead(TI-83 bug)
:If Z<0 or Z=0 Make sure Z(a.k.a. Y) has not fallen off the screen.
:Goto C If so, go to label C.
:End -
:Lbl C Label C
:1->M M will keep track of if you've made a hit or not. Default is no hit.
:If X>(C-1) and X<(C+6) Checks if your shot is in the target range, or in a place to cause a hit.
:Then -
:2->M Have M remember that there is a hit. Because it passed the check.
:X->K Backup of X, cause of the bug in the TI.
:Line(K,1,K-8,3 Draw an explosion around the current possition.
:Line(K,1,K+8,3 -
:Line(K,1,K-6,8 -
:Line(K,1,K+6,8 -
:Line(K,1,K-2,6 -
:Line(K,1,K+2,6 -
:End End of hit check.
:For(A,1,200) Another time delay
:End -
:If M=2 If target hit, then...
:Then -
:ClrHome Clear the home screen
:If B=1 Checks if you made a hit in one try.
:Then -
:For(I,1,3) This loop will make the text flash 3 times.
:Output(4,4,"FIRST TRY!" Draw text
:For(A,1,100) wait
:End -
:Output(4,4,"__________" Clear only that text (as opposed to clearing the whole screen)
:For(A,1,100) wait again
:End -
:End End the flashing loop
:Output(4,4,"FIRST TRY!:" draw text again, because it was erased when the loop finished.
:End End of If B=1 check
:If B>1 This really shouldn't be necessary, It should be obvious that you've take more
:Then than one shot. But I wrote this a while back.
:Output(4,4,B Outputs number of shots
:Output(4,8,"SHOTS" Outputs text
:End Ends B>1 condition
:Pause Pause until Enter key is hit.
:ClrHome Clear Home screen
:Goto D Goto Label D
:End End of M=2 condition
:ClrHome Clear screen if you missed the target
:Disp "SHOOT AGAIN:" Display text
:Goto B Go back to label B (choose shot power again)
:Lbl D Label D
:ClrHome Clear home screen
:Menu("PLAY AGAIN?","YES",A,"NO",E Basic Menu. Menu("TITLE","CHOICE 1",Label to go to,"CHoICE 2", ...)
:Lbl E Label E, end of game
:ClrHome Clear off the screen
:Stop Quit program, it'll also do this if it runs to the end of the program. So it's not necessary here
I wrote this code a long time ago, so there are many things I would have done different. My Gunner game better depicts parabolic motion, using real numbers for gravity and all.