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 test04_normal_weighting_scheme(variant_scalar_rgb):
from mitsuba.core import Vector3f
from mitsuba.render import Mesh
import numpy as np
"""Tests the weighting scheme that is used to compute surface normals."""
m = Mesh("MyMesh", 5, 2, has_vertex_normals=True)
vertices = m.vertex_positions_buffer()
normals = m.vertex_normals_buffer()
a, b = 1.0, 0.5
vertices[:] = [0, 0, 0, -a, 1, 0, a, 1, 0, -b, 0, 1, b, 0, 1]
n0 = Vector3f(0.0, 0.0, -1.0)
n1 = Vector3f(0.0, 1.0, 0.0)
angle_0 = ek.pi / 2.0
angle_1 = ek.acos(3.0 / 5.0)
n2 = n0 * angle_0 + n1 * angle_1
n2 /= ek.norm(n2)
n = np.vstack([n2, n0, n0, n1, n1]).transpose()
m.faces_buffer()[:] = [0, 1, 2, 0, 3, 4]
m.recompute_vertex_normals()
for i in range(5):
assert ek.allclose(normals[i * 3:(i + 1) * 3], n[:, i], 5e-4)
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 test01_create_mesh(variant_scalar_rgb):
from mitsuba.core import Struct, float_dtype
from mitsuba.render import Mesh
m = Mesh("MyMesh", 3, 2)
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, 1, 2, 0]
m.parameters_changed()
assert str(m) == """Mesh[
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 test01_create_mesh(variant_scalar_rgb):
from mitsuba.render import Mesh
m = Mesh("MyMesh", 3, 2)
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, 1, 2, 0]
m.parameters_changed()
m.surface_area() # Ensure surface area computed
assert str(m) == """Mesh[
def test08_mesh_add_attribute(variant_scalar_rgb):
from mitsuba.core import Struct, float_dtype
from mitsuba.render import Mesh
m = Mesh("MyMesh", 3, 2)
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, 1, 2, 0]
m.parameters_changed()
m.add_attribute("vertex_color",
3)[:] = [0.0, 1.0, 1.0, 0.0, 0.0, 0.0, 1.0, 1.0, 0.0]
assert str(m) == """Mesh[
def create_rectangle():
from mitsuba.render import Mesh
mesh = Mesh("rectangle", 4, 2, has_vertex_texcoords=True)
mesh.vertex_positions_buffer()[:] = [
0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 1.0, 0.0, 1.0, 1.0, 0.0
]
mesh.vertex_texcoords_buffer()[:] = [
0.0, 0.0, 1.0, 0.0, 0.0, 1.0, 1.0, 1.0
]
mesh.faces_buffer()[:] = [0, 1, 2, 1, 3, 2]
mesh.parameters_changed()
mesh.add_attribute("vertex_mono", 1, [1.0, 2.0, 3.0, 4.0])
mesh.add_attribute(
"vertex_color", 3,
[0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 1.0, 0.0, 1.0, 1.0, 0.0])
mesh.add_attribute("face_mono", 1, [0.0, 1.0])
mesh.add_attribute("face_color", 3, [0.0, 0.0, 0.0, 0.0, 0.0, 1.0])
return mesh
