prog8/examples/cube3d-stackvm.p8
2019-01-09 22:01:47 +01:00

122 lines
3.7 KiB
Lua

%import c64utils
%import c64flt
~ irq {
uword global_time
ubyte time_changed
sub irq() {
; activated automatically if run in StackVm
global_time++
time_changed = 1
}
}
~ main {
const uword width = 320
const uword height = 200
; vertices
float[8] xcoor = [ -1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0 ]
float[8] ycoor = [ -1.0, -1.0, 1.0, 1.0, -1.0, -1.0, 1.0, 1.0 ]
float[8] zcoor = [ -1.0, 1.0, -1.0, 1.0, -1.0, 1.0, -1.0, 1.0 ]
; edges (msb=from vertex, lsb=to vertex)
uword[12] edges = [$0001, $0103, $0302, $0200, $0405, $0507, $0706, $0604, $0004, $0105, $0206, $0307]
; storage for rotated coordinates
float[len(xcoor)] rotatedx
float[len(ycoor)] rotatedy
float[len(zcoor)] rotatedz
sub start() {
while true {
if irq.time_changed {
irq.time_changed = 0
vm_gfx_clearscr(0)
vm_gfx_text(8, 6, 1, "Spin")
vm_gfx_text(29, 11, 1, "to Win !")
for uword i in 0 to width/10 {
vm_gfx_line(i*2+width/2-width/10, 130, i*10.w, 199, 6)
}
rotate_vertices(irq.global_time as float / 30.0)
draw_edges()
}
}
}
sub rotate_vertices(float t) {
; rotate around origin (0,0,0)
; set up the 3d rotation matrix values
float cosa = cos(t)
float sina = sin(t)
float cosb = cos(t*0.33)
float sinb = sin(t*0.33)
float cosc = cos(t*0.78)
float sinc = sin(t*0.78)
float cosa_sinb = cosa*sinb
float sina_sinb = sina*sinb
float Axx = cosa*cosb
float Axy = cosa_sinb*sinc - sina*cosc
float Axz = cosa_sinb*cosc + sina*sinc
float Ayx = sina*cosb
float Ayy = sina_sinb*sinc + cosa*cosc
float Ayz = sina_sinb*cosc - cosa*sinc
float Azx = -sinb
float Azy = cosb*sinc
float Azz = cosb*cosc
for ubyte i in 0 to len(xcoor)-1 {
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]
}
}
sub draw_edges() {
sub toscreenx(float x, float z) -> word {
return x/(4.2+z) * (height as float) as word + width / 2
}
sub toscreeny(float y, float z) -> word {
return y/(4.2+z) * (height as float) as word + height / 2
}
; draw all edges of the object
for uword edge in edges {
ubyte e_from = msb(edge)
ubyte e_to = lsb(edge)
vm_gfx_line(toscreenx(rotatedx[e_from], rotatedz[e_from]), toscreeny(rotatedy[e_from], rotatedz[e_from]),
toscreenx(rotatedx[e_to], rotatedz[e_to]), toscreeny(rotatedy[e_to], rotatedz[e_to]), e_from+e_to)
}
; accentuate the vertices a bit with small boxes
for ubyte i in 0 to len(xcoor)-1 {
word sx = toscreenx(rotatedx[i], rotatedz[i])
word sy = toscreeny(rotatedy[i], rotatedz[i])
ubyte color=i+2
vm_gfx_pixel(sx-1, sy-1, color)
vm_gfx_pixel(sx, sy-1, color)
vm_gfx_pixel(sx+1, sy-1, color)
vm_gfx_pixel(sx-1, sy, color)
vm_gfx_pixel(sx, sy, color)
vm_gfx_pixel(sx+1, sy, color)
vm_gfx_pixel(sx-1, sy+1, color)
vm_gfx_pixel(sx, sy+1, color)
vm_gfx_pixel(sx+1, sy+1, color)
vm_gfx_pixel(sx, sy-2, color)
vm_gfx_pixel(sx+2, sy, color)
vm_gfx_pixel(sx, sy+2, color)
vm_gfx_pixel(sx-2, sy, color)
}
}
}