10 REM *****************************************************
 20 REM *                                                   *
 30 REM *                   SPACE WAR                       *
 40 REM *   For one or two Players on a Graphics Terminal   *
 50 REM *                  Jobst Brandt                     *
 60 REM *                 Hewlett-Packard                   *
 61 REM *                   (01 Apr 82)                     *
 65 REM *                                                   *
 66 REM *  Converted for TRS-80 MC-10 from the IBM version  *
 67 REM *       Requires MCX-128 expansion for MC-10        *
 68 REM *                 by Chris Osborn                   *
 69 REM *                   (26 Mar 15)                     *
 80 REM *                                                   *
 90 REM *****************************************************
 100  DIM C(46),OA(21,3),S(16,2),E(8,2)
 120  REM  Star locs and size: Xmax=720, Ymax=360, Smax=0, Smin=0
 130  DATA  0,0,0,0,10,0,-2,0,0,2,-1,0,3,2,-8,0,-2,-2,-4,0,-4
 140  DATA  -2,4,-2,4,0,2,-2,8,0,-3,2,1,0,0,2
 145  DATA -2,6,-2,-6,-6,-2,6,-2,2,-6,2,6,6,2,-6,2
 150  FOR I = 1 TO 4: READ Q(I): NEXT : FOR I = 1 TO 16: FOR J = 1 TO 2: READ S(I,J): NEXT J,I: FOR I = 1 TO 8: FOR J = 1 TO 2: READ E(I,J): NEXT J,I
 160  GOSUB 2740:G = R1
 170  REM  - Q CONTAINS Xlim,Ylim(screen),Distance,Maxsize(stars)
 220 M =  INT (2 *  RND(0) + 1):O = 0
 230 N1$ = "9":P$ = "2"
 250  GOSUB 2370
 270  CLS
 280 F1 = 0:F2 = 0:F3 = 0:V1$(1) = "20":V1$(2) = "20"
 290  PRINT  "(";P$;") One or two players? ";
 300  INPUT "";A$:P1$ = A$
 310  GOSUB 2000: ON R1 GOTO 290,290,290,270,290,2980
 320  IF A$ = "" THEN A$ = P$
 330 Q =  VAL (A$)
 340  IF Q <  > 1 AND Q <  > 2 THEN 290
 350 NP = Q
 360 P$ =  STR$ (NP)
 370  IF NP = 2 THEN 400
 380 N$(1) = "Player":N$(2) = "Enemy"
 390  GOTO 470
 400 N$(1) = "Spock":N$(2) = "Darth": FOR J = 1 TO 2
 410  PRINT  "("N$(J)")  Name of captain #";J;" ";
 420  INPUT "";A$
 430 P1$ = A$: GOSUB 2000: ON R1 GOTO 280,440,280,270,280,2980
 440  IF A$ = "" THEN 460
 450 P1$ = A$: GOSUB 2610:N$(J) = R1$
 460  NEXT J
 470  PRINT  "(";N1$;") How many stars? (0 to 18): ";
 480  INPUT "";A$
 490 P1$ = A$: GOSUB 2000: ON R1 GOTO 280,470,470,470,280,2980
 500  IF A$ = "" THEN A$ = N1$
 510 N =  VAL (A$)
 530  IF  ABS (N) < 0 OR  ABS (N) > 18 THEN 470
 540 N1$ =  STR$ (N)
 550  REM  O=Black hole
 560 O = 0: IF N < 0 THEN O = 1
 570 N =  ABS (N)
 580 Q(4) =  INT (10 - N / 6)
 590 Q(3) =  INT (Q(2) / 3) - N
 600  CLS 
 610  REM  -------------------- MAKE STARS ---------------------
 620 N = N + O
 630 FOR I = 1 TO N
 640 R = 0
 650 R = R + 1
 660  IF R > 20 THEN I = N + 1: GOTO 760
 670 OA(I,3) = Q(4)
 680  REM  -- J: 1 = Xpos, 2 = Ypos, 3 = Mass/Size --
 690  FOR J = 3 TO 1 STEP  - 1
 700 OA(I,J) =  INT ((Q(J) - 2 * OA(I,3)) *  RND(0) + OA(I,3))
 710  NEXT J:IF I = 1 THEN 760
 720 FOR J = 1 TO I - 1
 730 T = (OA(I,3) + OA(J,3) + 10) ^ 2
 740 IF (OA(I,1) - OA(J,1)) ^ 2 + (OA(I,2) - OA(J,2)) ^ 2 < T THEN J = I
 750  NEXT J:IF J > I THEN 650
 760  NEXT I:IF R > 20 THEN 630
 770  REM  ----------------- PLACE SPACE SHIPS -----------------
 780  REM  -- Space ship size = 5 --
 790 OA(N + 1,3) = 5:OA(N + 2,3) = 5
 800  FOR J = 1 TO 2
 810 T = 4 *  LEN (N$(J)): IF T < 10 THEN T = 10
 820  IF J = 1 THEN I = .28 * Q(1):Q = 0: GOTO 840
 830 T =  - T:I =  - .28 * Q(1):Q = Q(1)
 840 R = 0
 850 R = R + 1
 860  IF R > 20 THEN J = 3: GOTO 940
 870 X =  INT (I *  RND(0)) + Q + T
 880 Y =  INT ((Q(2) - 30) *  RND(0) + 20)
 890  FOR K = 1 TO N
 900  IF (X - OA(K,1)) ^ 2 + (Y - OA(K,2)) ^ 2 < (OA(K,3) * 2) ^ 2 THEN K = N + 1
 910  NEXT K:IF K > N + 1 THEN 850
 920 OA(N + J,1) = X
 930 OA(N + J,2) = Y
 940  NEXT J: IF J = 4 THEN 630
 950 A1$(1) = "0":A1$(2) = "180"
 960  IF NP > 1 THEN A$ = N$(1):N$(1) = N$(2):N$(2) = A$
 970  REM  -------------------- PLOT STARS ---------------------
 980  PMODE 2:SCREEN 2:PCLS
 990 Z1 = 3.14159 * (1 / 180)
 1000  FOR I = 0 TO 45
 1010 C(I + 1) =  COS (I * 10 * Z1)
 1020  NEXT I
 1030  FOR I = 1 TO N - O
 1040  FOR J = 1 TO 37
 1050 X =  INT (OA(I,1) + OA(I,3) * C(J) + .5)
 1060 Y =  INT (OA(I,2) - OA(I,3) * C(J + 9) + .5)
 1070  IF J = 1 THEN  LINE (X,Y) - (X,Y),PSET
 1080  LINE - (X,Y),PSET
 1090  NEXT J
 1110  NEXT I
 1130  REM  ------------------ PLOT SPACE SHIPS -----------------
 1140  FOR I = 1 TO 2
 1150 P1 = OA(N + I,1):P2 = OA(N + I,2):P3$ = N$(I):P4 = I: GOSUB 2120
 1160  NEXT I
 1170  IF A$(1,1) = "I" THEN 1450
 1180  GOTO 1210
 1190  REM  --------------------- PLAY GAME ---------------------
 1200 M = M -  INT (M / 2) * 2 + 1
 1210  IF NP = 1 THEN M = 1
 1240 A$=INKEY$:IF A$ = "" THEN 1240
 1245  PRINT  "(" + A1$(M) + ") ";N$(M);"'s, launch angle: ";
 1250 B = 20:F1 = 1
 1260  INPUT "";A$
 1270  IF A$ = "" THEN A$ = A1$(M)
 1280 P1$ = A$: GOSUB 2000: ON R1 GOTO 1240,980,1240,270,1240,2980
 1290 A =  VAL (A$)
 1300 A =  -  SGN (A) * ( ABS (A) -  INT ( ABS (A) / 360) * 360)
 1310 A1$(M) =  STR$ ( - A)
 1320  IF N = 0 THEN 1450
 1330  REM LOCATE 23,26
 1340  PRINT "(";V1$(M);") ";N$(M);"'s initial velocity: ";
 1350  INPUT "";A$
 1360  IF A$ = "" THEN A$ = V1$(M)
 1370 P1$ = A$: GOSUB 2000: ON R1 GOTO 1240,980,1330,270,1240,2980
 1380 B =  VAL (A$)
 1390  IF B >  = 0 AND B <  = 20 THEN 1420
 1400  PRINT "Velocity must be from 0 to 20"
 1410  GOTO 1330
 1420 V1$(M) =  STR$ (B)
 1450 U1 = 0:U2 = 0:V1 = 0:V2 = 0:F3 = 0
 1460 X = .35 * B *  COS (A * Z1)
 1470 Y = .35 * B *  SIN (A * Z1)
 1480 U = X + OA(N + M,1) + 8 *  COS (A * Z1)
 1490 V = Y + OA(N + M,2) + 8 *  SIN (A * Z1)
 1500 P1 = U:P2 = V: GOSUB 2230
 1510  IF F2 THEN 1570
 1520  REM  ----------------- DRAW ROCKET PATH ------------------
 1525 SCREEN 2
 1530 U1 =  INT (U + .5):V1 =  INT (V + .5)
 1540  IF U1 <  > U2 OR V1 <  > V2 THEN P1 = U1:P2 = V1: GOSUB 2290
 1550 U2 = U1:V2 = V1
 1560  REM  -- E = Xforce, F = Yforce --
 1570 E = 0:F = 0
 1580  FOR J = 1 TO N
 1590 R5 = OA(J,1) - U
 1600 R6 = OA(J,2) - V
 1610 R4 = R5 ^ 2 + R6 ^ 2
 1620 R3 =  SQR (R4)
 1630 R2 = R5 / R3
 1640 R1 = R6 / R3
 1650 G = .017 * (OA(J,3) ^ 3) / R4
 1660 E = E + G * R2
 1670 F = F + G * R1
 1680  NEXT J
 1690 X = X + E
 1700 Y = Y + F
 1710 U = U + X
 1720 V = V + Y
 1730  REM  ------------------ FIND COLLISIONS ------------------
 1740  IF F2 THEN 1790
 1750  RJ = 0:FOR J = 1 TO N + 2
 1755  IF J = N + 1 THEN 1780
 1760  IF O AND J = N THEN 1780
 1770  IF (U - OA(J,1)) ^ 2 + (V - OA(J,2)) ^ 2 < OA(J,3) ^ 2 THEN F1 = J:J = N + 3: RJ = 1
 1780  NEXT J: IF RJ THEN J = F1: GOTO 1880
 1790  IF U <  - Q(1) OR U > Q(1) * 2 OR V <  - Q(2) OR V > Q(2) * 2 THEN 1200
 1800 F2 = (U < 0 OR U > Q(1) OR V < 0 OR V > Q(2))
 1810  REM  -- F2=F3 (no change............) --
 1820  REM  -- F2=1  (just went off screen.) --
 1830  REM  -- F3=1  (just came onto screen) --
 1840  IF F2 = F3 THEN 1510
 1850  IF F3 THEN P1 = U:P2 = V: GOSUB 2230
 1860 F3 = F2
 1870  GOTO 1510
 1880  REM  ------------------ MAKE EXPLOSIONS ------------------
 1890 P1 = U + 2:P2 = V + 2: GOSUB 2230
 1900  FOR I = 1 TO 8:P1 = E(I,1):P2 = E(I,2): GOSUB 2250: NEXT 
 1910  IF J <  = N THEN 1200
 1920  REM LOCATE 23,16
 1930  PRINT N$(M);" destroyed ";N$(J - N);"'s ship!";
 1940  PRINT "   (Y) Again? : ";
 1950  INPUT "";A$
 1970  IF  MID$ (A$,1,2) = "//" THEN 2980
 1980 A$ =  LEFT$ (A$,1): IF A$ = "D" OR A$ = "I" THEN 980
 1985  IF A$ = "N" OR A$ = "E" THEN 2980
 1990  GOTO 270
 2000  REM  ******************* INPUT ******************* FNC ***
 2010 P1$ =  LEFT$ (P1$,1)
 2060  IF P1$ = "" THEN R1 = 0: RETURN 
 2061 P = 7
 2062 P = P - 1: IF P = 0 THEN 2100
 2063  IF  MID$ ("BDHS/E",P,1) = P1$ THEN 2080
 2064  GOTO 2062
 2080  IF  MID$ (A$,1,2) = "//" THEN P = 6
 2090  IF P = 3 THEN  GOSUB 2370
 2100 R1 = P: RETURN 
 2120  REM  **************** MAKE SHIPS ***************** FNS ***
 2140 S = (P4 - 1) * 2 - 1
 2150  GOSUB 2230
 2160  FOR K = 1 TO 16:P1 = S(K,1) * S:P2 = S(K,2): GOSUB 2250: NEXT 
 2210  RETURN 
 2230  REM  ***************** G CURSOR ****************** FNG$ **
 2240 CX = P1:CY = P2: RETURN 
 2250  REM   ***************** DRAW LINE *************************
 2260  IF CX >  = 0 AND CX <  = Q(1) AND CY >  = 0 AND CY <  = Q(2) AND CX + P1 >  = 0 AND CX + P1 <  = Q(1) AND CY + P2 >  = 0 AND CY + P2 <  = Q(2) THEN LINE (CX,CY) - (CX + P1,CY + P2),PSET
 2270 CX = CX + P1:CY = CY + P2
 2280  RETURN 
 2290  IF CX >  = 0 AND CX <  = Q(1) AND CY >  = 0 AND CY <  = Q(2) AND P1 >  = 0 AND P1 <  = Q(1) AND P2 >  = 0 AND P2 <  = Q(2) THEN  LINE (CX,CY) - (P1,P2),PSET
 2300 CX = P1:CY = P2: RETURN 
 2370  REM  ******************* HELP ******************** FNH ***
 2410  SCREEN 0:CLS
 2420  PRINT "SPACE WAR ";D$: REM LOCATE 7,1
 2430  PRINT  TAB( 26);"     Commands:": PRINT 
 2440  PRINT  TAB( 26);"      H = Help"
 2450  PRINT  TAB( 26);"      S = Start"
 2460  PRINT  TAB( 26);"      D = Display"
 2470  PRINT  TAB( 26);"      I = Instant replay after hit"
 2480  PRINT  TAB( 26);" / or B = Back"
 2490  PRINT  TAB( 26);"// or E = Exit": REM LOCATE 17,17
 2500  PRINT "Negative number of stars gives a BLACK HOLE"
 2510  PRINT "(Y) Are you ready to play? (Y/N): ";
 2520  INPUT "";A$
 2530 A$ =  LEFT$ (A$,2): IF A$ > "" THEN A =  ASC (A$):A$ =  CHR$ (A - 32 * (A > 96 AND A < 123)) +  MID$ (A$,2)
 2540  IF A$ = "N" OR A$ = "E" OR A$ = "//" THEN 2580
 2550  IF A$ = "H" THEN 2410
 2560  RETURN : POKE 49232,0: POKE 49239,0
 2570  RETURN 
 2580  CLS 
 2590  END 
 2610  REM  ************** FUNCTION DOWNSHIFT *********** FNS$ **
 2640 M = 0: IF P1$ = "" THEN  RETURN 
 2650  FOR I = 1 TO  LEN (P1$)
 2660 K =  ASC ( MID$ (P1$,I,1))
 2670  IF K = 32 THEN M = 0
 2680  IF K < 65 OR K > 91 THEN 2710
 2690  IF M THEN P1$ =  MID$ (P1$,1,I - 1) +  CHR$ (K + 32) +  MID$ (P1$,I + 1)
 2700 M = 1
 2710  NEXT I
 2720 R1$ = P1$: RETURN 
 2740  REM  *********** POLL TERMINAL CAPABILITY ******** FNi ***
 2750 R1 = 1:Q(1) = 255:Q(2) = 191
 2760  RETURN 
 2970  REM  ******************** EXIT ***************************
 2980  IF G THEN  TEXT 
 2990  CLS 
 3000  END