Read a point cloud.

ptCloud = pcread('teapot.ply');

Plot the point cloud.

figure
pcshow(ptCloud)
xlabel('X')
ylabel('Y')
zlabel('Z')

Create a transform object with a 45 degree rotation along the z-axis.

theta = pi/4;
rot = [cos(theta) sin(theta) 0; ...
      -sin(theta) cos(theta) 0; ...
               0          0  1];
trans = [0, 0, 0];
tform = rigid3d(rot,trans);

Transform the point cloud.

ptCloudOut = pctransform(ptCloud,tform);

Plot the transformed point cloud.

figure
pcshow(ptCloudOut)
xlabel('X')
ylabel('Y')
zlabel('Z')

This example shows affine transformation of a 3-D point cloud. The specified forward transform can be a rigid or nonrigid transform. The transformations shown includes rotation (rigid transform) and shearing (nonrigid transform) of the input point cloud.

Read a point cloud into the workspace.

ptCloud = pcread('teapot.ply');

A = [cos(pi/4) sin(pi/4) 0 0; ...
     -sin(pi/4) cos(pi/4) 0 0; ...
     0 0 1 0; ...
     0 0 0 1];
tform = affine3d(A);

ptCloudOut1 = pctransform(ptCloud,tform);

A = [1 0 0 0; ...
     0.75 1 0 0; ...
     0.75 0 1 0; ...
     0 0 0 1];
tform = affine3d(A);

ptCloudOut2 = pctransform(ptCloud,tform);

figure1 = figure('WindowState','normal');
axes1 = axes('Parent',figure1);
pcshow(ptCloud,'Parent',axes1); 
xlabel('X');
ylabel('Y');
zlabel('Z');
title('3-D Point Cloud','FontSize',14)

% Plot the rotation and shear affine transformed 3-D point clouds.
figure2 = figure('WindowState','normal');
axes2 = axes('Parent',figure2);
pcshow(ptCloudOut1,'Parent',axes2);
xlabel('X');
ylabel('Y');
zlabel('Z');
title({'Rotation of 3-D Point Cloud'},'FontSize',14)

figure3 = figure('WindowState','normal');
axes3 = axes('Parent',figure3);
pcshow(ptCloudOut2,'Parent',axes3);
xlabel('X');
ylabel('Y');
zlabel('Z');
title({'Shearing of 3-D Point Cloud'},'FontSize',14)

Read a point cloud into the workspace.

ptCloud = pcread('teapot.ply');

Create a displacement field D of same size as the point cloud.

D = zeros(size(ptCloud.Location));

Set the displacement field value along x-axis for the first half of the points to 7.

pthalf = ptCloud.Count/2;
D(1:pthalf,1) = 7;

Extract the indices of points within a region-of-interest (ROI) using the pointCloud method findNeighborsInRadius. Set the displacement field value along the x-, y-, and z-axis for points within the ROI to 4, 4, and -2, respectively.

indices = findNeighborsInRadius(ptCloud,[0 0 3.1],1.5);
D(indices,1:2) = 4;
D(indices,3) = -2;

Transform the point cloud using the displacement field.

ptCloudOut = pctransform(ptCloud,D);

Display the original and transformed point cloud.

figure
pcshow(ptCloud)
xlabel('X');
ylabel('Y');
zlabel('Z');
title('Original 3-D Point Cloud')

figure
pcshow(ptCloudOut)
xlabel('X');
ylabel('Y');
zlabel('Z');
title('Transformed 3-D Point Cloud Using Displacement Field')