def create_stairs(num_steps):
import numpy as np
from mitsuba.render import Mesh
size_step = 1.0 / num_steps
m = Mesh("stairs", 4 * num_steps, 4 * num_steps - 2)
params = traverse(m)
v = np.zeros((4 * num_steps, 3))
f = np.zeros((4 * num_steps - 2, 3))
for i in range(num_steps):
h = i * size_step
s1 = i * size_step
s2 = (i + 1) * size_step
k = 4 * i
v[k + 0] = [0.0, s1, h]
v[k + 1] = [1.0, s1, h]
v[k + 2] = [0.0, s2, h]
v[k + 3] = [1.0, s2, h]
f[k] = [k, k + 1, k + 2]
f[k + 1] = [k + 1, k + 3, k + 2]
if i < num_steps - 1:
f[k + 2] = [k + 2, k + 3, k + 5]
f[k + 3] = [k + 5, k + 4, k + 2]
m.vertex_positions_buffer()[:] = v.reshape(-1)
m.faces_buffer()[:] = f.reshape(-1)
m.recompute_bbox()
return m
def create_stairs_packet(num_steps):
assert mitsuba.variant() == 'packet_rgb'
from mitsuba.render import Mesh
size_step = 1.0 / num_steps
m = Mesh("stairs", vertex_struct, 4 * num_steps, index_struct,
4 * num_steps - 2)
v = m.vertices()
f = m.faces()
for i in range(num_steps):
h = i * size_step
s1 = i * size_step
s2 = (i + 1) * size_step
k = 4 * i
v[k + 0] = (0.0, s1, h)
v[k + 1] = (1.0, s1, h)
v[k + 2] = (0.0, s2, h)
v[k + 3] = (1.0, s2, h)
f[k] = (k, k + 1, k + 2)
f[k + 1] = (k + 1, k + 3, k + 2)
if i < num_steps - 1:
f[k + 2] = (k + 2, k + 3, k + 5)
f[k + 3] = (k + 5, k + 4, k + 2)
m.recompute_bbox()
return m
def create_single_triangle():
from mitsuba.render import Mesh
m = Mesh("tri", 3, 1)
m.vertex_positions_buffer()[:] = [
0.0, 0.0, 0.0, 1.0, 0.2, 0.0, 0.2, 1.0, 0.0
]
m.faces_buffer()[:] = [0, 1, 2]
m.recompute_bbox()
return m
def create_regular_tetrahedron():
from mitsuba.render import Mesh
m = Mesh("tetrahedron", 4, 4)
params = traverse(m)
m.vertex_positions_buffer()[:] = [
0, 0, 0, 0.8, 0.8, 0, 0.8, 0, 0.8, 0, 0.8, 0.8
]
m.faces_buffer()[:] = [0, 1, 2, 1, 2, 3, 0, 2, 2, 1, 3, 3, 3, 1, 0]
m.recompute_bbox()
return m
def create_single_triangle():
from mitsuba.render import Mesh
m = Mesh("tri", vertex_struct, 3, index_struct, 1)
v = m.vertices()
f = m.faces()
v[0] = (0, 0, 0)
v[1] = (1, 0.2, 0)
v[2] = (0.2, 1, 0)
f[0] = (0, 1, 2)
m.recompute_bbox()
return m
def test01_create_mesh(variant_scalar_rgb):
from mitsuba.core import Struct, float_dtype
from mitsuba.render import Mesh
vertex_struct = Struct() \
.append("x", Struct.Type.Float32) \
.append("y", Struct.Type.Float32) \
.append("z", Struct.Type.Float32)
index_struct = Struct() \
.append("i0", Struct.Type.UInt32) \
.append("i1", Struct.Type.UInt32) \
.append("i2", Struct.Type.UInt32)
m = Mesh("MyMesh", vertex_struct, 3, index_struct, 2)
v = m.vertices()
v[0] = (0.0, 0.0, 0.0)
v[1] = (0.0, 0.0, 1.0)
v[2] = (0.0, 1.0, 0.0)
m.recompute_bbox()
if float_dtype == 'f':
assert str(m) == """Mesh[
name = "MyMesh",
bbox = BoundingBox3f[
min = [0, 0, 0],
max = [0, 1, 1]
],
vertex_struct = Struct<12>[
float32 x; // @0
float32 y; // @4
float32 z; // @8
],
vertex_count = 3,
vertices = [36 B of vertex data],
face_struct = Struct<12>[
uint32 i0; // @0
uint32 i1; // @4
uint32 i2; // @8
],
face_count = 2,
faces = [24 B of face data],
disable_vertex_normals = 0,
surface_area = 0
]"""
else:
assert str(m) == """Mesh[
def create_regular_tetrahedron():
from mitsuba.render import Mesh
m = Mesh("tetrahedron", vertex_struct, 4, index_struct, 4)
v = m.vertices()
f = m.faces()
v[0] = (0, 0, 0)
v[1] = (0.8, 0.8, 0)
v[2] = (0.8, 0, 0.8)
v[3] = (0, 0.8, 0.8)
f[0] = (0, 1, 2)
f[1] = (2, 3, 0)
f[2] = (2, 1, 3)
f[3] = (3, 1, 0)
m.recompute_bbox()
return m
