def __init__(self, primitives, refine_immediately):
"""Default constructor for GridAccel."""
# initialize self.primitives with primitives for grid
if refine_immediately:
self.primitives = []
for primitive in primitives:
primitive.fully_refine(self.primitives)
else:
self.primitives = list(primitives)
# compute bounds and choose grid resolution
self.bounds = BBox()
for primitive in self.primitives:
self.bounds = union(self.bounds, primitive.world_bound())
delta = self.bounds.p_max - self.bounds.p_min
# find voxels_per_unit_dist for grid
max_axis = self.bounds.maximum_extent()
inv_max_width = 1.0 / delta[max_axis]
cube_root = 3.0 * pow(len(self.primitives), 1.0 / 3.0)
voxels_per_unit_dist = cube_root * inv_max_width
self.n_voxels = []
for axis in range(3):
self.n_voxels.append(
clamp(round_to_int(delta[axis] * voxels_per_unit_dist), 1, 64))
# compute voxel widths and allocate voxels
self.width = Vector()
self.inv_width = Vector()
for axis in range(3):
self.width[axis] = delta[axis] / self.n_voxels[axis]
if self.width[axis] == 0.0:
self.inv_width[axis] = 0.0
else:
self.inv_width[axis] = 1.0 / self.width[axis]
nv = self.n_voxels[0] * self.n_voxels[1] * self.n_voxels[2]
# array of voxels, initialized at None
self.voxels = [None] * nv
# add primitives to grid voxels
for primitive in self.primitives:
# find voxel extent of primitive
primitive_bound = primitive.world_bound()
v_min = []
v_max = []
for axis in range(3):
v_min.append(self._pos_to_voxel(primitive_bound.p_min, axis))
v_max.append(self._pos_to_voxel(primitive_bound.p_max, axis))
# add primitive to overlapping voxels
for z in range(v_min[2], v_max[2] + 1):
for y in range(v_min[1], v_max[1] + 1):
for x in range(v_min[0], v_max[0] + 1):
index = self._offset(x, y, z)
if self.voxels[index] is None:
self.voxels[index] = Voxel(primitive)
else:
self.voxels[index].add_primitive(primitive)
# create reader-writer mutex for grid
self.rw_lock = DummyRWLock()
def __init__(self, primitives, refine_immediately):
"""Default constructor for GridAccel."""
# initialize self.primitives with primitives for grid
if refine_immediately:
self.primitives = []
for primitive in primitives:
primitive.fully_refine(self.primitives)
else:
self.primitives = list(primitives)
# compute bounds and choose grid resolution
self.bounds = BBox()
for primitive in self.primitives:
self.bounds = union(self.bounds, primitive.world_bound())
delta = self.bounds.p_max - self.bounds.p_min
# find voxels_per_unit_dist for grid
max_axis = self.bounds.maximum_extent()
inv_max_width = 1.0 / delta[max_axis]
cube_root = 3.0 * pow(len(self.primitives), 1.0/3.0)
voxels_per_unit_dist = cube_root * inv_max_width
self.n_voxels = []
for axis in range(3):
self.n_voxels.append(clamp(
round_to_int(delta[axis] * voxels_per_unit_dist), 1, 64))
# compute voxel widths and allocate voxels
self.width = Vector()
self.inv_width = Vector()
for axis in range(3):
self.width[axis] = delta[axis] / self.n_voxels[axis]
if self.width[axis] == 0.0:
self.inv_width[axis] = 0.0
else:
self.inv_width[axis] = 1.0 / self.width[axis]
nv = self.n_voxels[0] * self.n_voxels[1] * self.n_voxels[2]
# array of voxels, initialized at None
self.voxels = [None] * nv
# add primitives to grid voxels
for primitive in self.primitives:
# find voxel extent of primitive
primitive_bound = primitive.world_bound()
v_min = []
v_max = []
for axis in range(3):
v_min.append(self._pos_to_voxel(primitive_bound.p_min, axis))
v_max.append(self._pos_to_voxel(primitive_bound.p_max, axis))
# add primitive to overlapping voxels
for z in range(v_min[2], v_max[2]+1):
for y in range(v_min[1], v_max[1]+1):
for x in range(v_min[0], v_max[0]+1):
index = self._offset(x, y, z)
if self.voxels[index] is None:
self.voxels[index] = Voxel(primitive)
else:
self.voxels[index].add_primitive(primitive)
# create reader-writer mutex for grid
self.rw_lock = DummyRWLock()
class GridAccel(Aggregate):
"""Class describing a GridAccel."""
def __init__(self, primitives, refine_immediately):
"""Default constructor for GridAccel."""
# initialize self.primitives with primitives for grid
if refine_immediately:
self.primitives = []
for primitive in primitives:
primitive.fully_refine(self.primitives)
else:
self.primitives = list(primitives)
# compute bounds and choose grid resolution
self.bounds = BBox()
for primitive in self.primitives:
self.bounds = union(self.bounds, primitive.world_bound())
delta = self.bounds.p_max - self.bounds.p_min
# find voxels_per_unit_dist for grid
max_axis = self.bounds.maximum_extent()
inv_max_width = 1.0 / delta[max_axis]
cube_root = 3.0 * pow(len(self.primitives), 1.0 / 3.0)
voxels_per_unit_dist = cube_root * inv_max_width
self.n_voxels = []
for axis in range(3):
self.n_voxels.append(
clamp(round_to_int(delta[axis] * voxels_per_unit_dist), 1, 64))
# compute voxel widths and allocate voxels
self.width = Vector()
self.inv_width = Vector()
for axis in range(3):
self.width[axis] = delta[axis] / self.n_voxels[axis]
if self.width[axis] == 0.0:
self.inv_width[axis] = 0.0
else:
self.inv_width[axis] = 1.0 / self.width[axis]
nv = self.n_voxels[0] * self.n_voxels[1] * self.n_voxels[2]
# array of voxels, initialized at None
self.voxels = [None] * nv
# add primitives to grid voxels
for primitive in self.primitives:
# find voxel extent of primitive
primitive_bound = primitive.world_bound()
v_min = []
v_max = []
for axis in range(3):
v_min.append(self._pos_to_voxel(primitive_bound.p_min, axis))
v_max.append(self._pos_to_voxel(primitive_bound.p_max, axis))
# add primitive to overlapping voxels
for z in range(v_min[2], v_max[2] + 1):
for y in range(v_min[1], v_max[1] + 1):
for x in range(v_min[0], v_max[0] + 1):
index = self._offset(x, y, z)
if self.voxels[index] is None:
self.voxels[index] = Voxel(primitive)
else:
self.voxels[index].add_primitive(primitive)
# create reader-writer mutex for grid
self.rw_lock = DummyRWLock()
def world_bound(self):
"""Return the bounding box in world space."""
return self.bounds
def can_intersect(self):
"""Return True if the aggregate can intersect."""
return True
def intersect(self, ray, intersection):
"""Compute the intersection with the primitives."""
# check ray against overall grid bounds
if self.bounds.inside(ray(ray.mint)):
ray_t = ray.mint
else:
intersected, t0, t1 = self.bounds.intersect_p(ray)
if not intersected:
self.rw_lock.release()
return False
ray_t = t0
grid_intersect = ray(ray_t)
# set up 3D DDA (Digital Differential Analyzer) for ray
pos = []
next_crossing_t = []
delta_t = []
step = []
out = []
for axis in range(3):
# compute current voxel for axis
pos.append(self._pos_to_voxel(grid_intersect, axis))
if ray.d[axis] == 0.0:
next_crossing_t.append(float('inf'))
delta_t.append(float('inf'))
step.append(1)
out.append(self.n_voxels[axis])
elif ray.d[axis] > 0.0:
# handle ray with positive direction for voxel stepping
next_crossing_t.append(
ray_t + (self._voxel_to_pos(pos[axis]+1, axis) - \
grid_intersect[axis]) / ray.d[axis])
delta_t.append(self.width[axis] / ray.d[axis])
step.append(1)
out.append(self.n_voxels[axis])
else:
# handle ray with negative direction for voxel stepping
next_crossing_t.append(
ray_t + (self._voxel_to_pos(pos[axis], axis) - \
grid_intersect[axis]) / ray.d[axis])
delta_t.append(-self.width[axis] / ray.d[axis])
step.append(-1)
out.append(-1)
# acquire a READ lock
self.rw_lock.acquire_read()
# walk ray through voxel grid
hit_something = False
while (True):
# check for intersection in current voxel and advance to next
voxel = self.voxels[self._offset(pos[0], pos[1], pos[2])]
if voxel is not None:
hit_something |= voxel.intersect(ray, intersection,
self.rw_lock)
# advance to next voxel
# find step_axis for stepping to next voxel
# don't use shift comparisons as it's slower than branching
# in python (see /timing/minimum.py)
if next_crossing_t[0] < next_crossing_t[1]:
if next_crossing_t[0] < next_crossing_t[2]:
step_axis = 0
else:
step_axis = 2
else:
if next_crossing_t[1] < next_crossing_t[2]:
step_axis = 1
else:
step_axis = 2
if ray.maxt < next_crossing_t[step_axis]:
break
pos[step_axis] += step[step_axis]
if pos[step_axis] == out[step_axis]:
break
next_crossing_t[step_axis] += delta_t[step_axis]
# release lock
self.rw_lock.release()
return hit_something
def intersect_p(self, ray):
"""Return True if the ray intersects any primitive."""
# check ray against overall grid bounds
if self.bounds.inside(ray(ray.mint)):
ray_t = ray.mint
else:
intersected, t0, t1 = self.bounds.intersect_p(ray)
if not intersected:
self.rw_lock.release()
return False
ray_t = t0
grid_intersect = ray(ray_t)
# set up 3D DDA (Digital Differential Analyzer) for ray
pos = []
next_crossing_t = []
delta_t = []
step = []
out = []
for axis in range(3):
# compute current voxel for axis
pos.append(self._pos_to_voxel(grid_intersect, axis))
if ray.d[axis] == 0.0:
next_crossing_t.append(float('inf'))
delta_t.append(float('inf'))
step.append(1)
out.append(self.n_voxels[axis])
elif ray.d[axis] > 0.0:
# handle ray with positive direction for voxel stepping
next_crossing_t.append(
ray_t + (self._voxel_to_pos(pos[axis]+1, axis) - \
grid_intersect[axis]) / ray.d[axis])
delta_t.append(self.width[axis] / ray.d[axis])
step.append(1)
out.append(self.n_voxels[axis])
else:
# handle ray with negative direction for voxel stepping
next_crossing_t.append(
ray_t + (self._voxel_to_pos(pos[axis], axis) - \
grid_intersect[axis]) / ray.d[axis])
delta_t.append(-self.width[axis] / ray.d[axis])
step.append(-1)
out.append(-1)
# acquire a READ lock
self.rw_lock.acquire_read()
# walk grid for shadow ray
while (True):
# check for intersection in current voxel and advance to next
voxel = self.voxels[self._offset(pos[0], pos[1], pos[2])]
if voxel and voxel.intersect_p(ray, self.rw_lock):
self.rw_lock.release()
return True
# advance to next voxel
# find step_axis for stepping to next voxel
# don't use shift comparisons as it's slower than branching
# in python (see /timing/minimum.py)
if next_crossing_t[0] < next_crossing_t[1]:
if next_crossing_t[0] < next_crossing_t[2]:
step_axis = 0
else:
step_axis = 2
else:
if next_crossing_t[1] < next_crossing_t[2]:
step_axis = 1
else:
step_axis = 2
if ray.maxt < next_crossing_t[step_axis]:
break
pos[step_axis] += step[step_axis]
if pos[step_axis] == out[step_axis]:
break
next_crossing_t[step_axis] += delta_t[step_axis]
# release lock
self.rw_lock.release()
return False
def _pos_to_voxel(self, point, axis):
"""Convert a 1D position into a voxel index."""
v = int((point[axis] - self.bounds.p_min[axis]) * self.inv_width[axis])
return clamp(v, 0, self.n_voxels[axis] - 1)
def _voxel_to_pos(self, index, axis):
"""Convert a voxel index to a 1D position."""
return self.bounds.p_min[axis] + index * self.width[axis]
def _offset(self, x, y, z):
"""Compute a voxel position based on its x, y, z indexes."""
return z * self.n_voxels[0] * self.n_voxels[1] + y * self.n_voxels[
0] + x
class GridAccel(Aggregate):
"""Class describing a GridAccel."""
def __init__(self, primitives, refine_immediately):
"""Default constructor for GridAccel."""
# initialize self.primitives with primitives for grid
if refine_immediately:
self.primitives = []
for primitive in primitives:
primitive.fully_refine(self.primitives)
else:
self.primitives = list(primitives)
# compute bounds and choose grid resolution
self.bounds = BBox()
for primitive in self.primitives:
self.bounds = union(self.bounds, primitive.world_bound())
delta = self.bounds.p_max - self.bounds.p_min
# find voxels_per_unit_dist for grid
max_axis = self.bounds.maximum_extent()
inv_max_width = 1.0 / delta[max_axis]
cube_root = 3.0 * pow(len(self.primitives), 1.0/3.0)
voxels_per_unit_dist = cube_root * inv_max_width
self.n_voxels = []
for axis in range(3):
self.n_voxels.append(clamp(
round_to_int(delta[axis] * voxels_per_unit_dist), 1, 64))
# compute voxel widths and allocate voxels
self.width = Vector()
self.inv_width = Vector()
for axis in range(3):
self.width[axis] = delta[axis] / self.n_voxels[axis]
if self.width[axis] == 0.0:
self.inv_width[axis] = 0.0
else:
self.inv_width[axis] = 1.0 / self.width[axis]
nv = self.n_voxels[0] * self.n_voxels[1] * self.n_voxels[2]
# array of voxels, initialized at None
self.voxels = [None] * nv
# add primitives to grid voxels
for primitive in self.primitives:
# find voxel extent of primitive
primitive_bound = primitive.world_bound()
v_min = []
v_max = []
for axis in range(3):
v_min.append(self._pos_to_voxel(primitive_bound.p_min, axis))
v_max.append(self._pos_to_voxel(primitive_bound.p_max, axis))
# add primitive to overlapping voxels
for z in range(v_min[2], v_max[2]+1):
for y in range(v_min[1], v_max[1]+1):
for x in range(v_min[0], v_max[0]+1):
index = self._offset(x, y, z)
if self.voxels[index] is None:
self.voxels[index] = Voxel(primitive)
else:
self.voxels[index].add_primitive(primitive)
# create reader-writer mutex for grid
self.rw_lock = DummyRWLock()
def world_bound(self):
"""Return the bounding box in world space."""
return self.bounds
def can_intersect(self):
"""Return True if the aggregate can intersect."""
return True
def intersect(self, ray, intersection):
"""Compute the intersection with the primitives."""
# check ray against overall grid bounds
if self.bounds.inside(ray(ray.mint)):
ray_t = ray.mint
else:
intersected, t0, t1 = self.bounds.intersect_p(ray)
if not intersected:
self.rw_lock.release()
return False
ray_t = t0
grid_intersect = ray(ray_t)
# set up 3D DDA (Digital Differential Analyzer) for ray
pos = []
next_crossing_t = []
delta_t = []
step = []
out = []
for axis in range(3):
# compute current voxel for axis
pos.append(self._pos_to_voxel(grid_intersect, axis))
if ray.d[axis] == 0.0:
next_crossing_t.append(float('inf'))
delta_t.append(float('inf'))
step.append(1)
out.append(self.n_voxels[axis])
elif ray.d[axis] > 0.0:
# handle ray with positive direction for voxel stepping
next_crossing_t.append(
ray_t + (self._voxel_to_pos(pos[axis]+1, axis) - \
grid_intersect[axis]) / ray.d[axis])
delta_t.append(self.width[axis] / ray.d[axis])
step.append(1)
out.append(self.n_voxels[axis])
else:
# handle ray with negative direction for voxel stepping
next_crossing_t.append(
ray_t + (self._voxel_to_pos(pos[axis], axis) - \
grid_intersect[axis]) / ray.d[axis])
delta_t.append(-self.width[axis] / ray.d[axis])
step.append(-1)
out.append(-1)
# acquire a READ lock
self.rw_lock.acquire_read()
# walk ray through voxel grid
hit_something = False
while(True):
# check for intersection in current voxel and advance to next
voxel = self.voxels[self._offset(pos[0], pos[1], pos[2])]
if voxel is not None:
hit_something |= voxel.intersect(ray, intersection, self.rw_lock)
# advance to next voxel
# find step_axis for stepping to next voxel
# don't use shift comparisons as it's slower than branching
# in python (see /timing/minimum.py)
if next_crossing_t[0] < next_crossing_t[1]:
if next_crossing_t[0] < next_crossing_t[2]:
step_axis = 0
else:
step_axis = 2
else:
if next_crossing_t[1] < next_crossing_t[2]:
step_axis = 1
else:
step_axis = 2
if ray.maxt < next_crossing_t[step_axis]:
break
pos[step_axis] += step[step_axis]
if pos[step_axis] == out[step_axis]:
break
next_crossing_t[step_axis] += delta_t[step_axis]
# release lock
self.rw_lock.release()
return hit_something
def intersect_p(self, ray):
"""Return True if the ray intersects any primitive."""
# check ray against overall grid bounds
if self.bounds.inside(ray(ray.mint)):
ray_t = ray.mint
else:
intersected, t0, t1 = self.bounds.intersect_p(ray)
if not intersected:
self.rw_lock.release()
return False
ray_t = t0
grid_intersect = ray(ray_t)
# set up 3D DDA (Digital Differential Analyzer) for ray
pos = []
next_crossing_t = []
delta_t = []
step = []
out = []
for axis in range(3):
# compute current voxel for axis
pos.append(self._pos_to_voxel(grid_intersect, axis))
if ray.d[axis] == 0.0:
next_crossing_t.append(float('inf'))
delta_t.append(float('inf'))
step.append(1)
out.append(self.n_voxels[axis])
elif ray.d[axis] > 0.0:
# handle ray with positive direction for voxel stepping
next_crossing_t.append(
ray_t + (self._voxel_to_pos(pos[axis]+1, axis) - \
grid_intersect[axis]) / ray.d[axis])
delta_t.append(self.width[axis] / ray.d[axis])
step.append(1)
out.append(self.n_voxels[axis])
else:
# handle ray with negative direction for voxel stepping
next_crossing_t.append(
ray_t + (self._voxel_to_pos(pos[axis], axis) - \
grid_intersect[axis]) / ray.d[axis])
delta_t.append(-self.width[axis] / ray.d[axis])
step.append(-1)
out.append(-1)
# acquire a READ lock
self.rw_lock.acquire_read()
# walk grid for shadow ray
while(True):
# check for intersection in current voxel and advance to next
voxel = self.voxels[self._offset(pos[0], pos[1], pos[2])]
if voxel and voxel.intersect_p(ray, self.rw_lock):
self.rw_lock.release()
return True
# advance to next voxel
# find step_axis for stepping to next voxel
# don't use shift comparisons as it's slower than branching
# in python (see /timing/minimum.py)
if next_crossing_t[0] < next_crossing_t[1]:
if next_crossing_t[0] < next_crossing_t[2]:
step_axis = 0
else:
step_axis = 2
else:
if next_crossing_t[1] < next_crossing_t[2]:
step_axis = 1
else:
step_axis = 2
if ray.maxt < next_crossing_t[step_axis]:
break
pos[step_axis] += step[step_axis]
if pos[step_axis] == out[step_axis]:
break
next_crossing_t[step_axis] += delta_t[step_axis]
# release lock
self.rw_lock.release()
return False
def _pos_to_voxel(self, point, axis):
"""Convert a 1D position into a voxel index."""
v = int((point[axis] - self.bounds.p_min[axis]) *
self.inv_width[axis])
return clamp(v, 0, self.n_voxels[axis]-1)
def _voxel_to_pos(self, index, axis):
"""Convert a voxel index to a 1D position."""
return self.bounds.p_min[axis] + index * self.width[axis]
def _offset(self, x, y, z):
"""Compute a voxel position based on its x, y, z indexes."""
return z*self.n_voxels[0]*self.n_voxels[1] + y*self.n_voxels[0] + x
