prog8/examples/cube3d.p8

107 lines
3.1 KiB
Plaintext
Raw Normal View History

%import syslib
2020-11-22 17:17:43 +00:00
%import test_stack
%import textio
2018-10-02 23:11:28 +00:00
2019-07-29 21:11:13 +00:00
main {
2018-10-02 23:11:28 +00:00
; vertices
2020-08-22 17:00:03 +00:00
word[] xcoor = [ -40, -40, -40, -40, 40, 40, 40, 40 ]
word[] ycoor = [ -40, -40, 40, 40, -40, -40, 40, 40 ]
word[] zcoor = [ -40, 40, -40, 40, -40, 40, -40, 40 ]
2018-10-02 23:11:28 +00:00
; storage for rotated coordinates
word[len(xcoor)] rotatedx
word[len(ycoor)] rotatedy
word[len(zcoor)] rotatedz
2018-10-02 23:11:28 +00:00
sub start() {
uword anglex
uword angley
uword anglez
repeat {
rotate_vertices(msb(anglex), msb(angley), msb(anglez))
2020-08-27 16:10:22 +00:00
txt.clear_screenchars(32)
draw_edges()
anglex+=1000
angley+=433
anglez+=907
2020-08-27 16:10:22 +00:00
txt.plot(0,0)
txt.print("3d cube! ")
txt.print_ub(c64.TIME_LO)
txt.print(" jiffies/fr = ")
txt.print_ub(60/c64.TIME_LO)
txt.print(" fps")
c64.TIME_LO=0
2020-11-22 17:17:43 +00:00
; test_stack.test()
2018-10-02 23:11:28 +00:00
}
}
sub rotate_vertices(ubyte ax, ubyte ay, ubyte az) {
2018-10-02 23:11:28 +00:00
; rotate around origin (0,0,0)
; set up the 3d rotation matrix values
2019-08-17 09:49:30 +00:00
word wcosa = cos8(ax)
word wsina = sin8(ax)
word wcosb = cos8(ay)
word wsinb = sin8(ay)
word wcosc = cos8(az)
word wsinc = sin8(az)
word wcosa_sinb = wcosa*wsinb / 128
word wsina_sinb = wsina*wsinb / 128
word Axx = wcosa*wcosb / 128
word Axy = (wcosa_sinb*wsinc - wsina*wcosc) / 128
word Axz = (wcosa_sinb*wcosc + wsina*wsinc) / 128
word Ayx = wsina*wcosb / 128
word Ayy = (wsina_sinb*wsinc + wcosa*wcosc) / 128
word Ayz = (wsina_sinb*wcosc - wcosa*wsinc) / 128
word Azx = -wsinb
word Azy = wcosb*wsinc / 128
word Azz = wcosb*wcosc / 128
2018-10-02 23:11:28 +00:00
ubyte @zp i
for i in 0 to len(xcoor)-1 {
2019-08-17 09:49:30 +00:00
; don't normalize by dividing by 128, instead keep some precision for perspective calc later
2020-03-11 19:47:42 +00:00
rotatedx[i] = Axx*xcoor[i] + Axy*ycoor[i] + Axz*zcoor[i]
rotatedy[i] = Ayx*xcoor[i] + Ayy*ycoor[i] + Ayz*zcoor[i]
rotatedz[i] = Azx*xcoor[i] + Azy*ycoor[i] + Azz*zcoor[i]
2018-10-02 23:11:28 +00:00
}
}
sub draw_edges() {
; plot the points of the 3d cube
; first the points on the back, then the points on the front (painter algorithm)
2018-10-02 23:11:28 +00:00
ubyte @zp i
word @zp rz
word @zp persp
byte sx
byte sy
for i in 0 to len(xcoor)-1 {
rz = rotatedz[i]
if rz >= 10 {
2019-08-17 09:49:30 +00:00
persp = 900 + rz/32
sx = rotatedx[i] / persp as byte + txt.DEFAULT_WIDTH/2
sy = rotatedy[i] / persp as byte + txt.DEFAULT_HEIGHT/2
2020-08-27 16:10:22 +00:00
txt.setcc(sx as ubyte, sy as ubyte, 46, 7)
}
2018-10-02 23:11:28 +00:00
}
for i in 0 to len(xcoor)-1 {
rz = rotatedz[i]
if rz < 10 {
2019-08-17 09:49:30 +00:00
persp = 900 + rz/32
sx = rotatedx[i] / persp as byte + txt.DEFAULT_WIDTH/2
sy = rotatedy[i] / persp as byte + txt.DEFAULT_HEIGHT/2
2020-08-27 16:10:22 +00:00
txt.setcc(sx as ubyte, sy as ubyte, 81, 7)
}
2018-10-02 23:11:28 +00:00
}
}
}