3D Multi-Point Positioning

Operator Function

This is an integrated operator that manually selects regions/manually inputs points/obtains coordinates of 2~9 points from registers, calculates the average value of these coordinates, outputs the center point coordinates, and performs position adjustment for the entire point cloud centered around this point.

Parameter Introduction

Input Parameters

Parameter	Range	Default Value	Description	Illustration
Input Image	0-8	0	IM number for image input

Calculation Parameters

Parameter	Range	Default Value	Description	Illustration
Point n	Point/3D Square Probe	3D Square Probe	Input point position coordinates or
Filter Method	No Filter/Statistical Filter/RANSAC Filter	No Filter	No Filter: No filtering of found edge points Statistical Filter: This filtering method first performs a best fit on the found edge points, then uses the standard deviation multiplication factor to calculate the distance threshold. Calculate the distance from all edge points to the fitted model. If this distance is greater than the distance threshold, it is considered an outlier. RANSAC: This filtering method is divided into two steps: hypothesis and verification. The hypothesis process involves randomly selecting n points from the point set for geometric model fitting; the verification process uses the remaining point set to calculate the distance to this geometric model. Points with distances less than the distance threshold are called inliers. If the number of inliers meets the threshold, the geometric model obtained from this hypothesis process is the best model, and iteration stops.
Standard Deviation Multiple		2.000
Distance Threshold		0.100	If the distance from a point to the output geometry is greater than this threshold, it will be filtered out.
Iteration Count		50	If the iteration count exceeds this number, the algorithm will stop iterating.
Position Adjustment			Adjust X Position: If enabled, adjust the X coordinate of the new origin to 0 Adjust Y Position: If enabled, adjust the Y coordinate of the new origin to 0 Adjust Z Position: If enabled, adjust the Z coordinate of the new origin to 0
Output Image	0-8	0	IM number for image output

Point n

Parameter	Range	Default Value	Description	Illustration
Enable	true/false	false	If enabled, activate this point
Point			Input point position coordinates
3D Square Probe			2D Window: Input point cloud within the window, extract points from this point cloud Box: Input point cloud within the box, extract points from this point cloud

As shown in the figure below: Input four points A, B, C, D, then obtain the center point O (x, y, z)

In the initial state, the X, Y, Z coordinates will be adjusted. The figure below shows the positions of each point after adjustment.

For adjusting X, Y, Z coordinates, you can choose arbitrarily:

• Transform x:

• Transform y:

• Transform z:

• Transform xy:

• Transform xz:

• Transform yz:

Result Display

Parameter	Range	Default Value	Description	Illustration
Positioning Point	true/false	false	If enabled, display the positioning point in the image
ROI Point Set	true/false	false	Region point set selected by ROI box. If enabled, display in the image

Output Parameters

Name	Type	Range	Description
Result	bool	true/false	true for success false for failure
Warning	bool	true/false	true indicates a warning false indicates no warning
Message	string		Output success, error, or warning messages. Empty if no error or warning.
Time	float		Operator execution time, unit: ms
point	point3d		Output positioning point

Tip

For more detailed explanations of parameter types, please refer to Type Definitions

Exception Troubleshooting

No.	Exception Information	Corresponding Parameter	Solution
1	Input filter mode is {0}, invalid filter mode	Filter Mode	Choose filter mode as one of: No Filter/RANSAC/Statistical Filter
2	Input point cloud is empty		Confirm if IM contains valid points. If no valid points, load point cloud or switch to IM with valid points
3	Input region {0} type is {1}, invalid region type	Index, Region Type	Region input type must be one of: 2D Window/2D Circular Window/Box/Cylindrical Box/Point Set
4	Input region number {0} is empty	Index	Check if this region number selects point cloud
5	Point {0} input mode is {1}, invalid mode input	Index, Mode	Mode must be Point/3D Square Probe
6	Number of selected points is less than 2		Enable at least 2 points
7	Polygon window vertex count for point {0} is less than 3, cannot form polygon	Index	Check the polygon window, increase its vertex count to 3 or more

Example Introduction

Engineering Design

1. Select the Load Point Cloud tool to load the required 3D point cloud image to IM0.

2. Select the 3D Multi-Point Positioning tool.

Tool Usage

1. Select the input image for the operation. The image number must match the IM number where the image is located in the project.

2. Enable multiple points, select 3D Square Probe type as Box, move the box to the position of the positioning point, enclosing the positioning point area.

Usage Tips

1. Use the ROI controller on the image window to drag or scale the box;
2. Directly modify the box's start or end point coordinates in the calculation parameters to adjust the box position and size;

3. Set the parameters.

4. Check the content you want to display in the result display section.

5. Click Test to check if the image window and parameters meet expectations.

6. If there are no issues, click Save. Run the operator in the run list, and then view the running results in the corresponding IM.