example of profile texture in slam

# Authors: Tianqi SONG <tianqisong0117@gmail.com>

# License: BSD (3-clause)
# sphinx_gallery_thumbnail_number = 2

importation of slam modules

import numpy as np
import trimesh.visual.color
from matplotlib import pyplot as plt

import slam.surface_profiling as surfpf
import slam.io as sio

loading an example mesh and its texture

mesh = sio.load_mesh("data/example_mesh.gii")
texture = sio.load_texture("data/example_texture.gii")

Select a vertex and get the coordinate and normal.

vert_index = 1500
vert0 = mesh.vertices[vert_index]
norm0 = mesh.vertex_normals[vert_index]

Set the parameters for surface profiling initial direction of rotation, rotation angle, length and number of sampling steps

init_rot_dir = np.array([1, 1, 1]) - vert0
rot_angle = 10
r_step = 0.1
max_samples = 45

Surface profiling, here we do the second round profiling

num_face = len(mesh.faces)
mesh_faces_id = np.linspace(0, num_face, num_face + 1).astype(int)
profile_samples, profile_co_faces = surfpf.second_round_profiling_vert(
    vert0, norm0, init_rot_dir, rot_angle, r_step, max_samples, mesh, mesh_faces_id
)

profile_points = profile_samples[:, :, 2]

Compute texture values of profile points

profile_samples = np.array([profile_samples])
profile_samples_fid = np.array([profile_co_faces])
profile_texture = surfpf.get_texture_value_on_profile(
    texture, mesh, profile_samples, profile_samples_fid
)

Visualize result Generate colors of profile points

# set color maps
color_map = plt.get_cmap("jet", 12)

# get texture value of profile points and mesh
profile_tex = profile_texture.reshape(profile_texture.size)
texture_value = texture.darray[0]

# put them together to generate the colors
prof_mesh_tex_color = np.hstack([profile_tex, texture_value])
prof_mesh_points_color = trimesh.visual.color.interpolate(
    prof_mesh_tex_color, color_map=color_map
)

mesh.visual.vertex_colors = prof_mesh_points_color[profile_texture.size :]

# Create point cloud of profiling points
prof_points_mesh = profile_points.reshape(
    profile_points.shape[0] * profile_points.shape[1], 3
)
prof_points_colors = prof_mesh_points_color[: profile_texture.size]
points_mesh = trimesh.points.PointCloud(
    prof_points_mesh, colors=np.array(prof_points_colors, dtype=np.uint8)
)

#scene = trimesh.Scene([points_mesh, mesh])
#scene.show()#smooth=False)