3D Surface Area

Operator Function

Input object surface point cloud, calculate the surface area of the point cloud, and output the calculation result.

Parameter Introduction

Input Parameters

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

Calculation Parameters

Parameter	Range	Default Value	Description	Illustration
Use Region Parameters	true/false	false	If enabled, use Region as input; if not enabled, use Input Image as input
Region	2D Window/2D Circular Window/2D Polygon Window/Box/Cylinder Box/Rotated Box/Point Set (binding only)	Box	Manually select an appropriate ROI region Can bind to select existing ROI regions
Search Radius	0-200	2.500	Set sphere radius for determining k-nearest neighborhoods This value may need adjustment based on point cloud density and distribution. For example, sparser point clouds may require larger search radii
Neighborhood Count	1-100	50	Set maximum neighborhood count for point cloud normal vector estimation Larger values may improve normal vector estimation robustness, especially for sparse or irregular point clouds. However, excessively large values may increase computational burden and introduce unnecessary noise. Smaller values may improve computational efficiency but could lead to less accurate normal vector estimation in some cases
Nearest Neighbor Distance Multiplier	0-50	2.500	Dynamically adjust maximum search distance for each sample point; larger values increase final sample point maximum search distance. When set to larger values: Search radius increases, meaning algorithm considers more neighboring points to construct triangles, which may be beneficial in sparser point cloud regions. However, if set too large, may cause over-connection and produce inaccurate triangles. When set to smaller values: Search radius decreases, algorithm considers fewer neighboring points. This may be beneficial in denser point cloud regions or when finer reconstruction is needed. However, if set too small, may miss points that should be connected, resulting in incomplete triangular meshes.

Result Display

Parameter	Range	Default Value	Description	Illustration
Surface Area	true/false	false	Surface area value; if enabled, displayed in the image
ROI Point Set	true/false	false	Only effective when Use Region Parameters is selected; the point set of the ROI selected region; if enabled, displayed 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 there is a warning false indicates there is none
Message	string		Outputs success, error, or warning information; if there is no error or warning, it is empty
Time	float		Operator execution time, unit: ms
surface_area	float		Surface area value
Note: When input is an array, all surface area measurements from the array will form an array

Tip

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

Exception Troubleshooting

No.	Exception Information	Corresponding Parameter	Solution
1	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
2	Input region type is {0}, invalid region type	Region Type	Region input type must be one of: 2D Window/2D Circular Window/2D Polygon Window/Box/Cylinder Box/Rotated Box/Point Set
3	{0} regions are empty	Region Count	1. Check each region for empty selections 2. Check each point set for empty point sets
4	Failed to calculate surface area with current parameters		Adjust surface reconstruction parameters: 1. Search radius 2. Maximum neighborhood count 3. Nearest neighbor distance multiplier
5	Output area value is too large		Recommend calculating surface area in segments
6	Input polygon vertex count less than 3, cannot form polygon		Add 2D polygon window vertices so vertex count is at least three

Example Introduction

Engineering Design

1. Select the Load Point Cloud tool to load the 3D point cloud image to be processed into IM0;

2. Select the 3D Surface Area tool.

Tool Usage

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

2. Either do not enable Use Region Parameters, or enable region and select region type as Box, move the box to the position to be measured, enclosing the point cloud to be measured.

Usage Tips

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

3. Set 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, then run the operator in the run list to view the results in the corresponding IM