!***********************************!
!				    !
!              LIFE.BAS		    !
!        Conway's Game of Life	    !
!    Implemented under AlphaBASIC   !
!        By David F. Pallmann	    !
!				    !
!***********************************!
!Subroutines required: VUE

	MAP1 A(20,40), S, 1		!source array
	MAP1 B(20,40), S, 1		!destination array
	MAP1 I, F, 6			!loop index
	MAP1 J, F, 6 			!loop index
	MAP1 R, F, 6			!current row
	MAP1 C, F, 6			!current column
	MAP1 LR, F, 6			!low row
	MAP1 HR, F, 6			!high row
	MAP1 LC, F, 6			!low column
	MAP1 HC, F, 6			!high column
	MAP1 COUNT, B, 2		!life count
	MAP1 TEXT, S, 80		!text line
	MAP1 GEN, F, 6			!generation
	MAP1 TOTAL, F, 6		!total number of life units

INIT:	PRINT TAB(-1,0);
	FOR I = 1 TO 20
	    FOR J = 1 TO 40
		B(I,J) = " "
		NEXT J
	    NEXT I

SCREEN:	PRINT TAB(-1,11);
	FOR I = 1 TO 20
	    PRINT TAB(I+1,1); "|";
	    PRINT TAB(1,I+1); "-";
	    PRINT TAB(1,I+21); "-";
	    PRINT TAB(I+1,42); "|";
	    PRINT TAB(22,I+1); "-";
	    PRINT TAB(22,I+21); "-";
	    NEXT I
	PRINT TAB(1,1); "+"; TAB(1,42); "+";
	PRINT TAB(22,1); "+"; TAB(22,42); "+";
	PRINT TAB(-1,12);
	PRINT TAB(3,52); "==  LIFE  ==";

ENTRY:	PRINT TAB(5,50); "Enter pattern";
	PRINT TAB(7,50); "Use VUE control chars";
	PRINT TAB(9,50); "Hit ESCAPE when done";
	XCALL VUE, B(1,1), 20, 40, 1, 1

GET2:	PRINT TAB(5,50); TAB(-1,9);
	PRINT TAB(7,50); TAB(-1,9);
	PRINT TAB(9,50); TAB(-1,9);

CORECT:	FOR I = 1 TO 20
	    FOR J = 1 TO 40
		IF B(I,J)="" THEN B(I,J) = " "
		IF B(I,J)<>" " THEN B(I,J) = "*"
		A(I,J) = B(I,J)
		NEXT J
	    NEXT I

DISPLAY:
	LR = 20 : HR = 0
	LC = 40 : HC = 0
	TOTAL = 0
	FOR I = 1 TO 20
	    FOR J = 1 TO 40
		IF B(I,J)="*" THEN TOTAL = TOTAL+1 : CALL WINDOW
		IF A(I,J)<>B(I,J) THEN PRINT TAB(I+1,J+1); B(I,J);
		PRINT TAB(I+1,J+1); B(I,J);
	        A(I,J) = B(I,J)
	        NEXT J
	    NEXT I
	I = GEN+6
	IF I>20 THEN I = I-15
	PRINT TAB(I,45);
	IF TOTAL=0 THEN PRINT "** Colony Extinct **"; TAB(22,50); : END
	PRINT "Generation"; GEN;
	PRINT  "  Population"; TOTAL;
	GEN = GEN+1

GENERATE:
	FOR I = LR-1 TO HR+1
	    FOR J = LC-1 TO HC+1
		IF I<1 OR I>20 THEN GOTO G'NEXT
		IF J<1 OR J>20 THEN GOTO G'NEXT
		CALL SCAN

G'NEXT:		NEXT J
	    NEXT I
	GOTO DISPLAY

SCAN:	COUNT = 0
	FOR R = I-1 TO I+1
	    FOR C = J-1 TO J+1
		IF R<1 OR R>20 THEN GOTO NEXT
		IF C<1 OR C>40 THEN GOTO NEXT
		IF R=I AND C=J THEN GOTO NEXT
		IF A(R,C)<>" " THEN COUNT = COUNT+1

NEXT:		NEXT C
	    NEXT R

	B(I,J) = " "
	IF A(I,J)="*" AND COUNT>1 AND COUNT<4 THEN B(I,J) = "*"
	IF A(I,J)=" " AND COUNT=3 THEN B(I,J) = "*"
	RETURN

WINDOW:	IF I<LR THEN LR = I
	IF I>HR THEN HR = I
	IF J<LC THEN LC = J
	IF J>HC THEN HC = J
	RETURN

	END