def default_OTF(x1, x2):
"""Creates a default opacity transfer function.
"""
maxs = max(x1, x2)
mins = min(x1, x2)
otf = PiecewiseFunction()
otf.add_point(mins, 0.0)
otf.add_point(maxs, 0.2)
return otf
def show_volume(D,
cm="Spectral",
minfact=0.1,
maxfact=0.9,
visible=True,
normalize=True):
print "Show volume"
mind = D.min()
D -= D.min()
src = mlab.pipeline.scalar_field(D)
ptpd = D.ptp()
if normalize:
R = (mind + minfact * ptpd, mind + maxfact * ptpd)
else:
R = (minfact - mind, maxfact - mind)
v = mlab.pipeline.volume(src, vmin=R[0], vmax=R[1])
if False and not (cm == "Spectral"):
ctf = ColorTransferFunction()
ctf.range = R
ctf.add_rgb_point(mind, 1, 1, 1)
ctf.add_rgb_point(R[0], 1, 1, 1)
ctf.add_rgb_point(R[1], 0, 0, 0)
ctf.add_rgb_point(mind + ptpd, 0, 0, 0)
v._volume_property.set_color(ctf)
v._ctf = ctf
v.update_ctf = True
if False:
from enthought.tvtk.util.ctf import PiecewiseFunction
otf = PiecewiseFunction()
otf.add_point(mind, 0)
otf.add_point(R[0], 0)
#otf.add_point(R[0]+0.1*ptpd, 0.1)
#otf.add_point(R[0]+0.2*ptpd, 0.3)
#otf.add_point(R[0]+0.3*ptpd, 0.5)
otf.add_point(R[0] + 0.2 * ptpd, 0.7)
otf.add_point(R[1], 1.0)
otf.add_point(mind + ptpd, 1.0)
v._otf = otf
v._volume_property.set_scalar_opacity(otf)
v.update_ctf = True
v.volume_mapper.cropping_region_planes = np.array(
[0., 1., 0., 1., 0., 1.])
v.volume_mapper.lock_sample_distance_to_input_spacing = True
print "done"
def make_volume_prop(mins=255, maxs=355):
"""Make a volume property for the testing."""
table = tvtk.VolumeProperty()
ctf = ColorTransferFunction()
ds = (maxs - mins) / 4.0
try:
ctf.range = (mins, maxs)
except Exception:
# VTK versions < 5.2 don't seem to need this.
pass
ctf.add_rgb_point(mins, 0.00, 0.0, 1.00)
ctf.add_rgb_point(mins + ds, 0.25, 0.5, 0.75)
ctf.add_rgb_point(mins + 2 * ds, 0.50, 1.0, 0.50)
ctf.add_rgb_point(mins + 3 * ds, 0.75, 0.5, 0.25)
ctf.add_rgb_point(maxs, 1.00, 0.0, 0.00)
otf = PiecewiseFunction()
otf.add_point(mins, 0.0)
otf.add_point(maxs, 0.2)
table.set_color(ctf)
table.set_scalar_opacity(otf)
return table, ctf, otf
# Use a GeometryFilter to cut out a slab
geom = mlab.pipeline.user_defined(edges, filter='GeometryFilter')
geom.filter.extent = [-0.8*extent, 0.8*extent,
-0.2*extent, 0.2*extent,
-0.8*extent, 0.8*extent, ]
geom.filter.extent_clipping = True
# Display connections in the selected slab as thick tubes.
mlab.pipeline.surface(mlab.pipeline.tube(geom,
tube_radius=0.25,
tube_sides=10,
),
colormap='Paired')
# Display the scalar field with volume rendering.
vol = mlab.pipeline.volume(delaunay)
# Change the opacity transfer function
from enthought.tvtk.util.ctf import PiecewiseFunction
otf = PiecewiseFunction()
otf.add_point(0, 0)
otf.add_point(N, 0.02)
vol._otf = otf
vol._volume_property.set_scalar_opacity(otf)
# And now choose a view, and re-enable rendering.
mlab.view(166, 80, 82)
fig.scene.disable_render = False
mlab.show()
