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 test04_normal_weighting_scheme(variant_scalar_rgb):
from mitsuba.core import Struct, float_dtype, Vector3f
from mitsuba.render import Mesh
import numpy as np
"""Tests the weighting scheme that is used to compute surface normals."""
vertex_struct = Struct() \
.append("x", Struct.Type.Float32) \
.append("y", Struct.Type.Float32) \
.append("z", Struct.Type.Float32) \
.append("nx", Struct.Type.Float32) \
.append("ny", Struct.Type.Float32) \
.append("nz", 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, 5, index_struct, 2)
v = m.vertices()
a, b = 1.0, 0.5
v['x'] = Float([0, -a, a, -b, b])
v['y'] = Float([0, 1, 1, 0, 0])
v['z'] = Float([0, 0, 0, 1, 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])
f = m.faces()
f[0] = (0, 1, 2)
f[1] = (0, 3, 4)
m.recompute_vertex_normals()
assert ek.allclose(v['nx'], n[:, 0], 5e-4)
assert ek.allclose(v['ny'], n[:, 1], 5e-4)
assert ek.allclose(v['nz'], n[:, 2], 5e-4)
