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#! /usr/bin/env python
# Rotate a 3D surface created using NURBS.
#
# Press left mouse button to toggle surface trimming.
# Press ESC to quit.
#
# See the GL manual for an explanation of NURBS.
from gl import *
from GL import *
from DEVICE import *
TRUE = 1
FALSE = 0
ORDER = 4
idmat = [1,0,0,0, 0,1,0,0, 0,0,1,0, 0,0,0,1]
surfknots = [-1, -1, -1, -1, 1, 1, 1, 1]
def make_ctlpoints():
c = []
#
ci = []
ci.append((-2.5, -3.7, 1.0))
ci.append((-1.5, -3.7, 3.0))
ci.append((1.5, -3.7, -2.5))
ci.append((2.5, -3.7, -0.75))
c.append(ci)
#
ci = []
ci.append((-2.5, -2.0, 3.0))
ci.append((-1.5, -2.0, 4.0))
ci.append((1.5, -2.0, -3.0))
ci.append((2.5, -2.0, 0.0))
c.append(ci)
#
ci = []
ci.append((-2.5, 2.0, 1.0))
ci.append((-1.5, 2.0, 0.0))
ci.append((1.5, 2.0, -1.0))
ci.append((2.5, 2.0, 2.0))
c.append(ci)
#
ci = []
ci.append((-2.5, 2.7, 1.25))
ci.append((-1.5, 2.7, 0.1))
ci.append((1.5, 2.7, -0.6))
ci.append((2.5, 2.7, 0.2))
c.append(ci)
#
return c
ctlpoints = make_ctlpoints()
trimknots = [0., 0., 0., 1., 1., 2., 2., 3., 3., 4., 4., 4.]
def make_trimpoints():
c = []
c.append((1.0, 0.0, 1.0))
c.append((1.0, 1.0, 1.0))
c.append((0.0, 2.0, 2.0))
c.append((-1.0, 1.0, 1.0))
c.append((-1.0, 0.0, 1.0))
c.append((-1.0, -1.0, 1.0))
c.append((0.0, -2.0, 2.0))
c.append((1.0, -1.0, 1.0) )
c.append((1.0, 0.0, 1.0))
return c
trimpoints = make_trimpoints()
def main():
init_windows()
setup_queue()
make_lights()
init_view()
#
set_scene()
setnurbsproperty( N_ERRORCHECKING, 1.0 )
setnurbsproperty( N_PIXEL_TOLERANCE, 50.0 )
trim_flag = 0
draw_trim_surface(trim_flag)
#
while 1:
while qtest():
dev, val = qread()
if dev == ESCKEY:
return
elif dev == WINQUIT:
dglclose(-1) # this for DGL only
return
elif dev == REDRAW:
reshapeviewport()
set_scene()
draw_trim_surface(trim_flag)
elif dev == LEFTMOUSE:
if val:
trim_flag = (not trim_flag)
set_scene()
draw_trim_surface(trim_flag)
def init_windows():
foreground()
#prefposition(0, 500, 0, 500)
wid = winopen('nurbs')
wintitle('NURBS Surface')
doublebuffer()
RGBmode()
gconfig()
lsetdepth(0x000, 0x7fffff)
zbuffer( TRUE )
def setup_queue():
qdevice(ESCKEY)
qdevice(REDRAW)
qdevice(RIGHTMOUSE)
qdevice(WINQUIT)
qdevice(LEFTMOUSE) #trimming
def init_view():
mmode(MPROJECTION)
ortho( -4., 4., -4., 4., -4., 4. )
#
mmode(MVIEWING)
loadmatrix(idmat)
#
lmbind(MATERIAL, 1)
def set_scene():
lmbind(MATERIAL, 0)
RGBcolor(150,150,150)
lmbind(MATERIAL, 1)
clear()
zclear()
#
rotate( 100, 'y' )
rotate( 100, 'z' )
def draw_trim_surface(trim_flag):
bgnsurface()
nurbssurface(surfknots, surfknots, ctlpoints, ORDER, ORDER, N_XYZ)
if trim_flag:
bgntrim()
nurbscurve(trimknots, trimpoints, ORDER-1, N_STW)
endtrim()
endsurface()
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)
main()
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