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#! /ufs/guido/bin/sgi/python
# Fancy NURBS demo. Require Z buffer and Panel Library.
from gl import *
from GL import *
from DEVICE import *
from nurbsdata import *
import panel
#
# flags = trim_f, invis_f, cpvis_f, tpvis_f, axvis_f, freeze_f
#
TRIM = 0
VIS = 1
CPVIS = 2
TPVIS = 3
AXVIS = 4
FREEZE = 5
flags = [0, 1, 0, 0, 0, 0]
def draw_axis () :
cpack (0x0)
zero = (0.0, 0.0, 0.0)
#
one = (1.0, 0.0, 0.0)
smallline (zero, one)
cmov (1.0, 0.0, 0.0)
charstr ('x')
#
one = (0.0, 1.0, 0.0)
smallline (zero, one)
cmov (0.0, 1.0, 0.0)
charstr ('y')
#
one = (0.0, 0.0, 1.0)
smallline (zero, one)
cmov (0.0, 0.0, 1.0)
charstr ('z')
DELTA = 0.1
def cross (p) :
p0 = [p[0], p[1], p[2]]
p1 = [p[0], p[1], p[2]]
for i in range (0, 3) :
p0[i] = p0[i] + DELTA
p1[i] = p1[i] - DELTA
smallline (p0, p1)
p0[i] = p0[i] - DELTA
p1[i] = p1[i] + DELTA
def smallline (p0, p1) :
bgnline ()
v3f (p0)
v3f (p1)
endline ()
def draw_pts (pnts, color) :
linewidth (2)
cpack (color)
for i in pnts :
cross (i)
def init_windows():
foreground()
wid = winopen('nurbs')
wintitle('NURBS Surface')
doublebuffer()
RGBmode()
gconfig()
lsetdepth(0x000, 0x7fffff)
zbuffer( TRUE )
def init_view():
mmode(MPROJECTION)
ortho( -5., 5., -5., 5., -5., 5. )
#
mmode(MVIEWING)
loadmatrix(idmat)
#
lmbind(MATERIAL, 1)
def set_scene(flags):
#
lmbind(MATERIAL, 0)
RGBcolor(150,150,150)
lmbind(MATERIAL, 1)
clear()
zclear()
#
if not flags[FREEZE] :
rotate( 100, 'y' )
rotate( 100, 'z' )
def draw_trim_surface(flags):
pnts = ctlpoints
if flags[VIS] :
bgnsurface()
nurbssurface(surfknots,surfknots,pnts,ORDER,ORDER,N_XYZ)
if flags[TRIM]:
bgntrim()
nurbscurve(trimknots,trimpoints,ORDER-1,N_STW)
endtrim()
endsurface()
#
if flags[CPVIS] :
for i in pnts :
draw_pts (i, RED)
#
if flags[TPVIS] :
tpts = trimpoints
draw_pts (tpts, YELLOW)
#
if flags[AXVIS] :
draw_axis ()
#
swapbuffers()
def make_lights():
lmdef(DEFLMODEL,1,[])
lmdef(DEFLIGHT,1,[])
#
# define material #1
#
a = []
a = a + [EMISSION, 0.0, 0.0, 0.0]
a = a + [AMBIENT, 0.1, 0.1, 0.1]
a = a + [DIFFUSE, 0.6, 0.3, 0.3]
a = a + [SPECULAR, 0.0, 0.6, 0.0]
a = a + [SHININESS, 2.0]
a = a + [LMNULL]
lmdef(DEFMATERIAL, 1, a)
#
# turn on lighting
#
lmbind(LIGHT0, 1)
lmbind(LMODEL, 1)
def main():
init_windows()
make_lights()
init_view()
#
panel.needredraw()
panels = panel.defpanellist('nurbs.s')
p = panels[0]
#
def cbtrim (a) :
flags[TRIM:TRIM+1] = [int (a.val)]
p.trim.upfunc = cbtrim
#
def cbquit (a) :
import sys
sys.exit (1)
p.quit.upfunc = cbquit
#
def cbmotion (a) :
flags[FREEZE:FREEZE+1] = [int (a.val)]
p.motion.upfunc = cbmotion
#
def cbxyzaxis (a) :
flags[AXVIS:AXVIS+1] = [int (a.val)]
p.xyzaxis.upfunc = cbxyzaxis
#
def cbtrimpnts (a) :
flags[TPVIS:TPVIS+1] = [int (a.val)]
p.trimpnts.upfunc = cbtrimpnts
#
def cbcntlpnts (a) :
flags[CPVIS:CPVIS+1] = [int (a.val)]
p.cntlpnts.upfunc = cbcntlpnts
#
def cbnurb (a) :
flags[VIS:VIS+1] = [int (a.val)]
p.nurb.upfunc = cbnurb
#
set_scene(flags)
setnurbsproperty( N_ERRORCHECKING, 1.0 )
setnurbsproperty( N_PIXEL_TOLERANCE, 50.0 )
draw_trim_surface(flags)
#
while 1:
act = panel.dopanel()
#
wid = panel.userredraw ()
if wid :
winset (wid)
reshapeviewport()
set_scene(flags)
draw_trim_surface(flags)
#
set_scene(flags)
draw_trim_surface(flags)
main()
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