It's a real valuable contribution to the AR world.

2022-01-07 Adding the third-person view and the accuracy controls. Instead of fixed values for measurement accuracy and mean point distance, the following formulas are used: - Measurement accuracy = base + increment * (object distance) - Mean point distance = increment * (object distance).

Once, the shape, size, position, orientation of an object surface is known, there are a variety of applications. YouTube CurvSurf, GitHub CurvSurf, FindSurface Web Demo.

The slope sign as shown in the previous answer is rendered based on: A gazing point on the object surface The surface normal at the gazing point The vertical (gravitational) direction.

The slope of an object surface can be calculated as below: Plane fitting to the LiDAR measurement points of the surface The slope is the ratio of horizontal/vertical of the plane normal. The slope sign as shown in the attached picture is rendered based on: A gazing point on the object surface The surface normal at the gazing point. The source codes for detecting and measuring the geometric primitives of planes, spheres, cylinders, cones, tori from LiDAR points are available.

The ToF (time of flight) 3D-camera of iPad Pro 2020/2021, iPhone Pro 12/13 and iPhone Pro Max 12/13 has physically 64 (16 stacks of rod of 4 cells) VCSELs (vertical cavity surface emitting laser). The 64 laser pulses are multiplied with 3x3 to 576 by a DOE (diffraction optical element). The 576 rebounded laser pulses from object surfaces are detected and the individual time elapses are measured by SPAD (single-photon avalanche diode) image sensor. The 576 depth points are interpolated with RGB images to the 256x192 depthMap of 60 Hz. Apple has released the access API to the 256x192 depthMap but not to the 576 depth points.

Hi, It may be worth to test "real-time recognition and measurement of planes / spheres / cylinders / cones / tori in point cloud generated with LiDAR".

FindSurface-GUIDemo-iOS (Swift)

The rawFeaturePoints generated without LiDAR is relatively inaccurate, unreliable, and unstable. A stable and accurate real-time detection of planes, spheres, cylinders, cones, tori is possible by using LiDAR. https://github.com/CurvSurf/FindSurface-GUIDemo-iOS

The number of the current raw laser points is 576 (squared 24x24 = 4x16x3x3. iPad Pro LiDAR, iPhone 12 Pro, iPhone 12 Pro Max). The advanced ML algorithm of Apple interpolating the 576 depth points together with RGB image generates the 256x192 depth map, a decision of compromise. The number 576 and 256x192 may be increased in the future. You can enjoy the current performance of 256x192 depth map of 60 Hz. Super fast real-time detection of planes / spheres / cylinders / cones / tori in DepthMap