Solid5 3/8

 BBS: Inland Empire Archive
Date: 03-21-93 (03:41)             Number: 353
From: RICH GELDREICH               Refer#: NONE
  To: ALL                           Recvd: NO  
Subj: Solid5 3/8                     Conf: (2) Quik_Bas

'Page 3 of SOLID5.BAS begins here.
s1! = SIN(a1!): c1! = COS(a1!)
s2! = SIN(a2!): c2! = COS(a2!)
lx = 128 * s1! * c2!        'convert spherical coordinates to a vector
ly = 128 * s1! * s2!        'scale up by 128 for integer math
lz = 128 * c1!

FOR a = -128 TO 128         'precalculate the three light source tables
    lx(a + 128) = lx * a    'for fast Lambert shading
    ly(a + 128) = ly * a
    lz(a + 128) = lz * a
NEXT

PRINT "Strike a key...": DO: LOOP WHILE INKEY$ = ""

R1 = 0: R2 = 0: R3 = 0      'three angles of rotation
ox = 0: oy = -50: oz = 1100 'object's origin (this program cannot _
currently
                            'handle the object when it goes behind the
_
viewer!)
s = 1: t = 0

SCREEN 7, , 0, 0
OUT &H3C8, 0                'set 16 shades
FOR a = 0 TO 15
    OUT &H3C9, (a * 34) \ 10
    OUT &H3C9, (a * 212) \ 100
    OUT &H3C9, (a * 4) \ 10
    IF a = 7 THEN OUT &H3C7, 16: OUT &H3C8, 16
NEXT
LINE (0, 100)-(319, 199), 9, BF
LINE (0, 0)-(319, 99), 3, BF
SCREEN 7, , 1, 0
LINE (0, 100)-(319, 199), 9, BF
LINE (0, 0)-(319, 99), 3, BF

YHigh(0) = -32768: ShadowYHigh(0) = -32768
YHigh(1) = -32768: ShadowYHigh(1) = -32768
DO
    'Flip active and work pages so user doesn't see our messy drawing
    SCREEN 7, , s, t: SWAP s, t

    'Wait for vertical retrace to reduce flicker
    WAIT &H3DA, 8

    'Erase the old image from the screen
    IF YHigh(s) <> -32768 THEN
        IF YHigh(s) < 100 THEN
            LINE (XLow(s), YLow(s))-(XHigh(s), YHigh(s)), 3, BF
        ELSEIF YLow(s) < 100 THEN
            LINE (XLow(s), YLow(s))-(XHigh(s), 99), 3, BF
            LINE (XLow(s), 100)-(XHigh(s), YHigh(s)), 9, BF
        ELSE
            LINE (XLow(s), YLow(s))-(XHigh(s), YHigh(s)), 9, BF
        END IF
    END IF
    IF ShadowYHigh(s) <> -32768 THEN
        LINE (ShadowXLow(s), ShadowYLow(s))-(ShadowXHigh(s), ShadowYHig_
h(s)), 9, BF
    END IF
    RotatePoints
    CullPolygons
    ShadePolygons

    XLow(s) = 32767: XHigh(s) = -32768
    YLow(s) = 32767: YHigh(s) = -32768
    DrawShadows
    DrawObject

    R1 = (R1 + D1) MOD 360: IF R1 < 0 THEN R1 = R1 + 360
    R2 = (R2 + D2) MOD 360: IF R2 < 0 THEN R2 = R2 + 360
    R3 = (R3 + D3) MOD 360: IF R3 < 0 THEN R3 = R3 + 360
    oz = oz + dz: ox = ox + dx
    IF oz < 600 THEN
        oz = 600: dz = 0
    ELSEIF oz > 8000 THEN
        oz = 8000: dz = 0
    END IF
    IF ox < -4000 THEN
        ox = -4000: dx = 0
    ELSEIF ox > 4000 THEN
        ox = 4000: dx = 0
    END IF
    a$ = INKEY$
    SELECT CASE a$
    CASE "4"
        D1 = D1 - 2
    CASE "6"
        D1 = D1 + 2
    CASE "8"
        D2 = D2 - 2
    CASE "2"
        D2 = D2 + 2
    CASE "5"
'Continued on page 4

--- MsgToss 2.0b
 * Origin: Computer Co-Op - Voorhees, NJ | Ted Hare (1:266/29)