'===========================================================================
' Subject: VOXEL LANDSCAPE                   Date: 09-23-98 (22:33)       
' Author:  Shawn                             Code: QB, QBasic, PDS        
' Origin:  TopFiero@aol.com                Packet: GRAPHICS.ABC
'===========================================================================
'  Voxel terrain generator for QuickBasic/Qbasic.
'  This program features more detailed terrain than 3dland.bas.
'  This sample was also taken from a graphics engine I use in one of my
'  games.  The terrain color can be changed further by changing the T variable
'  to the value 1 or 2.  When the program displays the word DONE, press
'  a key to return to the menu.  Use this program freely, but please send
'  me any revisions or variations.  I like to see how others can use this
'  idea.  I apologize for the routine containing line numbers, but this is
'  the easiest way I can convert it to run well in Qbasic.  I recommend
'  you have a Pentium 133 or faster to run the routine up to speed.  Or try
'  compiling it.  Send questions or comments to     TopFiero@aol.com

1 SCREEN 13: CLS : CLEAR
5 GOTO 1000
10 SCREEN 13: CLS
11 PL = 0
12 FOR I = 100 TO 160: PLL = CINT(PL * .67): IF PLL > 60 THEN PLL = 60
13 IF T = 1 THEN PALETTE I, 65536 * PL
14 IF T = 2 THEN PALETTE I, 65536 + 256 * PL
15 IF T = 3 THEN PALETTE I, 65536 + 256 * PLL + PL
17 IF T = 4 THEN PALETTE I, 65536 * PL + 256 * PL + PL
20 PL = PL + 1: NEXT I
21 PL = 0
22 FOR I = 170 TO 230: PLL = PL * 2: IF PLL > 60 THEN PLL = 60
23 PALETTE I, 65536 * PLL + 256 * PL + PL: PL = PL + 1: NEXT I
30 Z = 10 + 300 * RND: ZZ = 100 - 95 * RND: MV = 20 * RND
35 EEE = 100 * RND: IF EEE < 30 THEN GOTO 40 ELSE GOTO 50
40 FOR I = 0 TO 60: LINE (0, 99 - I)-(319, 99 - I), 230 - I: NEXT I
42 LINE (0, 100)-(319, 199), 230, BF
45 GOTO 80
50 FOR I = 0 TO 60: CIRCLE (Z, ZZ), 80 - I, 170 + I
52 PAINT (Z, ZZ), 170 + I, 170 + I
55 NEXT I
80 FOR I = 0 TO 500
81 X = 319 * RND: XX = 190 * RND: XCLR = POINT(X, XX)
82 IF XCLR > 220 THEN GOTO 81
83 IF XCLR > 180 THEN VCLR = (31 - ((220 - XCLR) / 4) * RND) ELSE VCLR = 17 + 13 * RND
85 PSET (X, XX), VCLR: NEXT I

100 DIM Z(320), X(320), CLR(320)
110 Z(0) = 0: X(0) = 100: SZ = 1: CLR(0) = 130
120 FOR I = 1 TO 320: Z(I) = Z(I - 1) + SZ
125 X(I) = X(I - 1) - SZ + (SZ * 2) * RND
127 CLR(I) = CLR(I - 1) - 5 + (10 * RND): IF CLR(I) < 100 THEN CLR(I) = 100
128 IF CLR(I) > 160 THEN CLR(I) = 160
130 LINE (Z(I), X(I))-(Z(I) + SZ, X(I) + SZ), CLR(I), BF: NEXT I
180 CHK = 0
190 SZ = SZ * 1.012
195 Z(0) = 0 - (SZ - 1) * 160: X(0) = X(0) + SZ * RND
200 FOR I = 1 TO 320: Z(I) = Z(I - 1) + SZ
205 X(I) = X(I) - SZ / 4 + SZ * RND: IF X(I) < X(I - 1) - SZ THEN X(I) = X(I - 1) - SZ
207 IF X(I) > X(I - 1) + SZ THEN X(I) = X(I - 1) + SZ
209 IF Z(I) < -1 OR Z(I) > 320 THEN GOTO 220
210 CLR(I) = CLR(I) - 4 + (8 * RND)
211 IF CLR(I) < CLR(I - 1) - 3 THEN CLR(I) = CLR(I - 1) - 3
212 IF CLR(I) > CLR(I - 1) + 3 THEN CLR(I) = CLR(I - 1) + 3
217 IF CLR(I) < 100 THEN CLR(I) = 100
218 IF CLR(I) > 160 THEN CLR(I) = 160
219 LINE (Z(I), X(I))-(Z(I) + SZ + 1, X(I) + SZ + 1), CLR(I), BF
220 IF X(I) > 199 THEN CHK = CHK + 1: IF CHK > 319 THEN GOTO 300
225 NEXT I
230 KY$ = INKEY$: IF KY$ = "" THEN GOTO 240 ELSE GOTO 300
240 CHK = 0: GOTO 190
300 LOCATE 1, 1: PRINT "Done...."
310 KY$ = INKEY$: IF KY$ = "" THEN GOTO 310
350 GOTO 1000
1000 PL = 0
1001 FOR I = 100 TO 160: PALETTE I, 65536 * PL: PL = PL + 1: NEXT I
1020 LOCATE 1, 1
1030 PRINT "Example of Voxel type terrain generation"
1035 PRINT "written in QuickBasic version 4.5."
1040 PRINT "": PRINT "    Select color choice:"
1050 PRINT "1 - DESERT"
1055 PRINT "2 - ICE"
1070 PRINT "3 - EXIT"
1080 R = 100 * RND: KY$ = INKEY$: IF KY$ = "1" THEN T = 3: GOTO 1100
1081 IF KY$ = "2" THEN T = 4: GOTO 1100
1084 IF KY$ = "3" THEN END
1085 GOTO 1080
1100 GOTO 10