PureBoard

Code: Alles auswählen

Dim Shared As single  posx, posy, posz 
Dim Shared As Single x, y, z 
Dim Shared As Single dd, de, dx, dy, dz, dyi, dxi 
Dim Shared As Single horiz, sdz, p, d, h 
Dim Shared As Integer hei(4096 - 1), col(4096 - 1) 
Dim Shared As Integer sx,i
Dim Shared As Single sinang,cosang,ang, r160

Screen 13

'Generate palette
For z = 0 To 63
   Palette z, Rgb(z / 2, z, z)
Next z

For z = 0 To 63
   Palette z + 64, Rgb(z, z, z \ 2)
Next z
   
'Generate interesting height & color maps
p = 0
For y = 0 To 63
   For x = 0 To 63
      d = 15 * 15 - ((x And 31) - 16) ^ 2 - ((y And 31) - 16) ^ 2
      If d > 0 And ((x Xor y) And 32) Then
         hei(p) = 64 - Sqr(d)
         col(p) = (x + y) * .5
      Else
         hei(p) = 64
         col(p) = (Cos(x * .2) + Sin(y * .3)) * 3 + 88
      End If
      p = p + 1
   Next x
Next y

'Initialize starting position
posx = 0
posy = 0
posz = 40 * 65536
ang = 0
horiz = -50
r160 = 1 / 160
dd = 65536 * r160 'Increment size
de = dd * 128     'Scan out 128 units
sdz = (100 - horiz) * 65536 * r160

Do
   cosang = Cos(ang) * 65536
   sinang = Sin(ang) * 65536
   dx = sinang + cosang
   dxi = -sinang * r160
   dy = sinang - cosang
   dyi = cosang * r160

   'For each column in 320*200 mode...
   For sx = 0 To 319
      'Fast ray trace! No *'s or /'s in here (\ 65536 is a shift)
      x = posx
      y = posy
      z = posz
      dz = sdz
      p = sx + 63680
      For d = 0 To de Step dd
         x += dx
         y += dy
         z += dz
         i = (((x * 64) And &HFC00000) + (y And &H3F0000)) \ 65536
         h = hei(i) * 65536
         Do While h < z
            PSet (p Mod 320, p \ 320), col(i)
            p -= 320
            z -= d
            dz -= dd
         Loop
      Next d
      dx += dxi
      dy += dyi
   
      'Finish off rest of line
      Do While p >= 19200
         PSet (p Mod 320, p \ 320), 0
         p = p - 320
      Loop
   Next sx

   'Move position & angle
   If Multikey(&h50) Then
      posx -= cosang * 4
      posy -= sinang * 4
   End If
   If Multikey(&h48) Then
      posx += cosang * 4
      posy += sinang * 4
   End If
   If Multikey(&h1E) And posz < 2621440 Then posz += 1 * 65536
   If Multikey(&h10) And posz > 0 Then posz -= 1 * 65536
   If Multikey(&h4B) Then ang -= .04
   If Multikey(&h4D) Then ang += .04
   
   Sleep 1
Loop Until Multikey(&h01)