Thunderbolt (Sinclair QL) by Stephen Poole

PUR80 – Thunderbolt_bas game by Stephen Poole, (QL Forum).

Code written and tested on SINCLAIR QL, (Preferably use QPC2 emulator).

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1 CLEAR:PAPER 0:MODE 8:WINDOW 512,256,0,0:g=DATE:CSIZE 0,0:k=0:q=75:h=40:i=-1:f=4
2 REPeat r:CLS:n=q+h*i:s RND(30 TO 120),98:IF KEYROW(1)=8:STOP:ELSE IF k>9:STOP
3 DEFine PROCedure s(x,y)
4 LOCal L,c,a,b,j:GO SUB 9:IF k>9:RETurn :END IF :p=0:FOR L=1 TO 7
5 c=RND(-25 TO 25):a=x-c:b=y-14:IF b<0 OR p=1:p=0:RETurn :END IF :p=KEYROW(1)=64
6 j=8-y/14:INK j:IF b<14:SELect a:=n-7 TO n+7:k=k+1:BEEP 9999,k:GO SUB 9:PAUSE 1
7 LINE x,y TO a,b:IF p:INK 0:GO SUB 9:i=-i:n=q+h*i:INK j:GO SUB 9:p=0:END IF
8 x=a:y=b:PAUSE f:IF RND(2)=0:s a,b:END IF :END FOR L: END DEFine
9 GO SUB 10:FOR z=1 TO 3:CURSOR n,8,-3,0:PRINT k:END FOR z: RETurn
10 ARC n-4,11 TO n+4,11,PI:FILL 1:CIRCLE n,6,3:FILL 0:AT 1,1:PRINT DATE-g :RETurn

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Program description :

1 Clear out memory : MODE 8 colours : WINDOW format : g start_timer : character           size small : k lifecounter : q screen_center : h center_offset :i left_or_right :f pause_speed

2 Main_loop : blank_screen : n viking_position : s bolt(start_position) :

  IF ESCape key hit or life=10 ? then STOP 

3 DEFine thunderbolt animation (current_position)

4 non-global variables L loop, c next_position, a x_offset, b y_down, j bolt_ink

  GOSUB viking_head : k if dead go to main loop : p space_bar

L loop to flash_downwards 

5 c flash_offset : a lower x_position : b lower y_position : 

  if b<0 ground_level or p=1 spacebar_hit then next thunderbolt_section :

  p see if spacebar_hit

6 j calculate ink_colour : if b=ground_level, compare, a bolt, to n viking positions : if viking_hit, k increment_lives, beep_deeper and redraw_viking on line 9 : wait 1/50th second

7 draw_bolt : if p=1 spacebar hit : erase viking(black ink) : jump sideways :

  p=0 reset spacebar

8 new bolt_position : f wait : 1/3 chance to start a lateral_bolt : end_loop

9 draw the lives_number (in the viking) : return to the calling statement.

10 draw_horns, head and timer.  Return to the calling statement.

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This program was rapidly written at short notice, using a few of the QL’s built in features. It has been tested on a Sinclair QL original machine too, via a floppy disc interface, which can read the program as it stands : Hit the (ESC)ape key, then type, in the lower black window, SAVE flp1_ThunderBolt_bas and hit (ENTER). 

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Any time the program halts, just type in RUN and hit ENTER.

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