# \#how-to **URL:** https://forum.techsoft3d.com/tag/how-to/21.md [Latest](https://forum.techsoft3d.com/latest.md) · [Categories](https://forum.techsoft3d.com/categories.md) · [Tags](https://forum.techsoft3d.com/tags.md) --- ## [Investigate on A3D\_LOAD\_CANNOT\_LOAD\_MODEL in C# HOOPS Exchange](https://forum.techsoft3d.com/t/investigate-on-a3d-load-cannot-load-model-in-c-hoops-exchange/5209)
**Author:** [@giulia.picciau](https://forum.techsoft3d.com/u/giulia.picciau)\ **Replies:** 1\ **Last updated:** [September 4, 2026, 2:42pm UTC](https://forum.techsoft3d.com/t/investigate-on-a3d-load-cannot-load-model-in-c-hoops-exchange/5209 "2026-09-04T14:42:08Z")
Hello, I am able to load and process CAD files with the HOOPS Exchange C# API, but on a specific Naviswork model the loading process fails. I have pinpointed the issue being in the call to API.A3DAsmModelFileLoadFromFil… --- ## [HOOPS AI Inside a HOOPS Visualize Desktop + Exchange Application: Similar-Part Search Across 10,000 CAD Files](https://forum.techsoft3d.com/t/hoops-ai-inside-a-hoops-visualize-desktop-exchange-application-similar-part-search-across-10-000-cad-files/5203)
**Author:** [@Toshi-TS3D](https://forum.techsoft3d.com/u/Toshi-TS3D)\ **Replies:** 0\ **Last updated:** [August 17, 2026, 4:01am UTC](https://forum.techsoft3d.com/t/hoops-ai-inside-a-hoops-visualize-desktop-exchange-application-similar-part-search-across-10-000-cad-files/5203 "2026-08-17T04:01:47Z")
HOOPS AI Inside a HOOPS Visualize Desktop + Exchange Application: Similar-Part Search Across 10,000 CAD Files Last time I confirmed that a native application can call HOOPS AI directly through a C ABI bridge with CPython… --- ## [2D text (angled) with background](https://forum.techsoft3d.com/t/2d-text-angled-with-background/5202)
**Author:** [@simon](https://forum.techsoft3d.com/u/simon)\ **Replies:** 0\ **Last updated:** [August 14, 2026, 11:03pm UTC](https://forum.techsoft3d.com/t/2d-text-angled-with-background/5202 "2026-08-14T23:03:59Z")
For 2D texts, by default, backgrounds will be screen aligned. If you call HC\_Set\_Text\_Path() to angle you texts, text’s background will look like the screenshot below. If you want to maintain background size, you s… --- ## [Using HOOPS AI from a Fully Local Desktop Application](https://forum.techsoft3d.com/t/using-hoops-ai-from-a-fully-local-desktop-application/5200)
**Author:** [@Toshi-TS3D](https://forum.techsoft3d.com/u/Toshi-TS3D)\ **Replies:** 0\ **Last updated:** [August 7, 2026, 1:50am UTC](https://forum.techsoft3d.com/t/using-hoops-ai-from-a-fully-local-desktop-application/5200 "2026-08-07T01:50:30Z")
Using HOOPS AI from a Fully Local Desktop Application I installed HOOPS AI, worked through the Jupyter notebook tutorials, then wrapped it as a REST API with FastAPI, and after that put an MCP server in front of it so an… --- ## [How to: Apply texture to each face of a shell (HPS)](https://forum.techsoft3d.com/t/how-to-apply-texture-to-each-face-of-a-shell-hps/5187)
**Author:** [@simon](https://forum.techsoft3d.com/u/simon)\ **Replies:** 0\ **Last updated:** [July 17, 2026, 11:35pm UTC](https://forum.techsoft3d.com/t/how-to-apply-texture-to-each-face-of-a-shell-hps/5187 "2026-07-17T23:35:31Z")
Following sample code apply texture to separate faces of a shell. You can copy/paste sample to hps\_mfc\_sandbox. Screenshot: Sample Code: SegmentKey modelKey = GetCanvas().GetFrontView().GetAttachedModel().GetS… --- ## [Version Compatibility Issue: HC 2025.6.1 Models Not Supported in HC 2025.6.0](https://forum.techsoft3d.com/t/version-compatibility-issue-hc-2025-6-1-models-not-supported-in-hc-2025-6-0/5182)
**Author:** [@raja.r](https://forum.techsoft3d.com/u/raja.r)\ **Replies:** 1\ **Last updated:** [July 16, 2026, 10:15pm UTC](https://forum.techsoft3d.com/t/version-compatibility-issue-hc-2025-6-1-models-not-supported-in-hc-2025-6-0/5182 "2026-07-16T22:15:14Z")
We understand that HOOPS Communicator 2025.6.1 is a Windows-only patch and that other platforms should continue using 2025.6.0. However, 2025.6.0 is no longer available for download on Windows, so Windows users are forc… --- ## [Understanding Cascaded Attribute Evaluation When Importing Prototype and ProductOccurrence Separately](https://forum.techsoft3d.com/t/understanding-cascaded-attribute-evaluation-when-importing-prototype-and-productoccurrence-separately/5172)
**Author:** [@diliji2008](https://forum.techsoft3d.com/u/diliji2008)\ **Replies:** 0\ **Last updated:** [June 29, 2026, 10:02pm UTC](https://forum.techsoft3d.com/t/understanding-cascaded-attribute-evaluation-when-importing-prototype-and-productoccurrence-separately/5172 "2026-06-29T22:02:04Z")
\# Understanding Cascaded Attribute Evaluation Across Prototype Boundaries Hi, I’m implementing a CAD importer based on HOOPS Exchange and have some questions about the intended usage of \`A3DMiscCascadedAttributesPush()… --- ## [I tried running HOOPS AI V1.1 headless on Ubuntu 24.04 (EC2)](https://forum.techsoft3d.com/t/i-tried-running-hoops-ai-v1-1-headless-on-ubuntu-24-04-ec2/5165)
**Author:** [@Toshi-TS3D](https://forum.techsoft3d.com/u/Toshi-TS3D)\ **Replies:** 0\ **Last updated:** [June 24, 2026, 6:59am UTC](https://forum.techsoft3d.com/t/i-tried-running-hoops-ai-v1-1-headless-on-ubuntu-24-04-ec2/5165 "2026-06-24T06:59:22Z")
I tried running HOOPS AI V1.1 headless on Ubuntu 24.04 (EC2) HOOPS AI V1.1 added Linux support, which is great news if you’re deploying to servers instead of workstations. But most server deployments are headless — no di… --- ## [How-to: Use Physically Based Rendering](https://forum.techsoft3d.com/t/how-to-use-physically-based-rendering/1356)
**Author:** [@gabriel.peragine](https://forum.techsoft3d.com/u/gabriel.peragine)\ **Replies:** 5\ **Last updated:** [June 5, 2026, 8:59pm UTC](https://forum.techsoft3d.com/t/how-to-use-physically-based-rendering/1356 "2026-06-05T20:59:15Z")
Physically Based Rendering is a set of rendering techniques which simulate how light and surface materials interact in the natural world. The goal is to create images which are more realistic than traditional shading app… --- ## [How to pick custom MeasureMarkup with mouse for context menu operations (e.g., deletion)?](https://forum.techsoft3d.com/t/how-to-pick-custom-measuremarkup-with-mouse-for-context-menu-operations-e-g-deletion/5139)
**Author:** [@3213265944](https://forum.techsoft3d.com/u/3213265944)\ **Replies:** 1\ **Last updated:** [April 28, 2026, 11:37am UTC](https://forum.techsoft3d.com/t/how-to-pick-custom-measuremarkup-with-mouse-for-context-menu-operations-e-g-deletion/5139 "2026-04-28T11:37:32Z")
I am encountering a challenge regarding the interaction with MeasureMarkup in HOOPS Communicator. I have implemented several custom MeasureMarkup instances in my project. My specific requirement is to be able to “pick” … --- ## [How to highlight object by point using custom operator (HPS::PanOrbitZoomOperator)](https://forum.techsoft3d.com/t/how-to-highlight-object-by-point-using-custom-operator-hps-panorbitzoomoperator/5074)
**Author:** [@phu\_bn](https://forum.techsoft3d.com/u/phu_bn)\ **Replies:** 5\ **Last updated:** [April 16, 2026, 6:56am UTC](https://forum.techsoft3d.com/t/how-to-highlight-object-by-point-using-custom-operator-hps-panorbitzoomoperator/5074 "2026-04-16T06:56:15Z")
I want that when I click on a point on the screen, the item containing that point will be highlighted. Then, I would like to maintain the highlight state while still being able to perform panOrbit actions. My idea is to… --- ## [\[Hoops Visualize iOS\] How to do it: Find the nodeId when the user taps an item on the model](https://forum.techsoft3d.com/t/hoops-visualize-ios-how-to-do-it-find-the-nodeid-when-the-user-taps-an-item-on-the-model/5117)
**Author:** [@phu\_bn](https://forum.techsoft3d.com/u/phu_bn)\ **Replies:** 5\ **Last updated:** [April 16, 2026, 6:54am UTC](https://forum.techsoft3d.com/t/hoops-visualize-ios-how-to-do-it-find-the-nodeid-when-the-user-taps-an-item-on-the-model/5117 "2026-04-16T06:54:56Z")
I’m using the Hoops Visualize app on iOS for picking I have a modal tree (containing a list of model node items). When I tap a line/face on the model, they are highlighted. When I tap again, the highlight should be can… --- ## [Request for Access to HOOPS AI Model Download Resources](https://forum.techsoft3d.com/t/request-for-access-to-hoops-ai-model-download-resources/5127)
**Author:** [@nihui](https://forum.techsoft3d.com/u/nihui)\ **Replies:** 2\ **Last updated:** [April 14, 2026, 4:01pm UTC](https://forum.techsoft3d.com/t/request-for-access-to-hoops-ai-model-download-resources/5127 "2026-04-14T16:01:32Z")
I’m currently trying to run a test to evaluate the effectiveness of CAD similarity retrieval. After downloading the SDK, I ran the Jupyter Notebook code, but I found that the model referenced in the code was not include… --- ## [Lower 3D geometry quality in E2E (Playwright) vs normal browser](https://forum.techsoft3d.com/t/lower-3d-geometry-quality-in-e2e-playwright-vs-normal-browser/5123)
**Author:** [@raja.r](https://forum.techsoft3d.com/u/raja.r)\ **Replies:** 3\ **Last updated:** [April 10, 2026, 11:44am UTC](https://forum.techsoft3d.com/t/lower-3d-geometry-quality-in-e2e-playwright-vs-normal-browser/5123 "2026-04-10T11:44:42Z")
Hi team, We are observing reduced 3D geometry quality when loading the same model using E2E testing tools (Playwright - Chromium) compared to a normal browser. Expected (Normal Browser) Full geometry detail Clean,… --- ## [How to get linked file list of a RVT model?](https://forum.techsoft3d.com/t/how-to-get-linked-file-list-of-a-rvt-model/5116)
**Author:** [@820110017](https://forum.techsoft3d.com/u/820110017)\ **Replies:** 1\ **Last updated:** [March 30, 2026, 2:05pm UTC](https://forum.techsoft3d.com/t/how-to-get-linked-file-list-of-a-rvt-model/5116 "2026-03-30T14:05:35Z")
Hello, Just like importing the SLDASM model, when I import the main file, I can get the list of dependent parts. If I import an rvt file, is there an interface that can obtain information about other files it references… --- ## [How to Manage Inheritance Flags](https://forum.techsoft3d.com/t/how-to-manage-inheritance-flags/5112)
**Author:** [@Man](https://forum.techsoft3d.com/u/Man)\ **Replies:** 0\ **Last updated:** [March 24, 2026, 8:46am UTC](https://forum.techsoft3d.com/t/how-to-manage-inheritance-flags/5112 "2026-03-24T08:46:23Z")
This article explains how inheritance flags control graphical attributes in HOOPS Exchange, including visibility, color, transparency, line style, and layer. While the concept applies to all attributes, this guide mainly… --- ## [Sample of creating thumbnail of a RVT model](https://forum.techsoft3d.com/t/sample-of-creating-thumbnail-of-a-rvt-model/5111)
**Author:** [@820110017](https://forum.techsoft3d.com/u/820110017)\ **Replies:** 1\ **Last updated:** [March 24, 2026, 2:25am UTC](https://forum.techsoft3d.com/t/sample-of-creating-thumbnail-of-a-rvt-model/5111 "2026-03-24T02:25:43Z")
Hi, Is there any sample code of creating thumbnail of a RVT model ？（Using HOOPS Exchange） Thanks. --- ## [How-to obtain BIM data from an RVT file?](https://forum.techsoft3d.com/t/how-to-obtain-bim-data-from-an-rvt-file/5099)
**Author:** [@502815549](https://forum.techsoft3d.com/u/502815549)\ **Replies:** 9\ **Last updated:** [March 18, 2026, 1:50am UTC](https://forum.techsoft3d.com/t/how-to-obtain-bim-data-from-an-rvt-file/5099 "2026-03-18T01:50:46Z")
How can I obtain BIM data from an RVT file using Exchange？ Does the RVt format support reading BIM data? Can Exchange edit and set BIM data? --- ## [HOOP EXCHANGE missing file problem](https://forum.techsoft3d.com/t/hoop-exchange-missing-file-problem/5103)
**Author:** [@820110017](https://forum.techsoft3d.com/u/820110017)\ **Replies:** 2\ **Last updated:** [March 13, 2026, 3:18am UTC](https://forum.techsoft3d.com/t/hoop-exchange-missing-file-problem/5103 "2026-03-13T03:18:24Z")
Hi, The following question was raised when we used libconvert before, and the answer we received was that it could not be implemented. Now that we are using EXCHANGE, can we correctly calculate the relative path between… --- ## [How can i get the face\`s perimeter？](https://forum.techsoft3d.com/t/how-can-i-get-the-face-s-perimeter/5100)
**Author:** [@3213265944](https://forum.techsoft3d.com/u/3213265944)\ **Replies:** 4\ **Last updated:** [March 12, 2026, 2:10am UTC](https://forum.techsoft3d.com/t/how-can-i-get-the-face-s-perimeter/5100 "2026-03-12T02:10:21Z")
I can get the nodeID and faceIndex, and I can also get all the edges, but if I want to get the perimeter of a face, I need to find out which edges belong to that face. How can I get this data through the web-viewer API? … --- ## [Generating Visualize 3DF Project Build Files](https://forum.techsoft3d.com/t/generating-visualize-3df-project-build-files/5066)
**Author:** [@mike](https://forum.techsoft3d.com/u/mike)\ **Replies:** 1\ **Last updated:** [February 25, 2026, 10:43pm UTC](https://forum.techsoft3d.com/t/generating-visualize-3df-project-build-files/5066 "2026-02-25T22:43:01Z")
With the release of 3DF 30.40, project files are no longer included in the customer packages. The package includes CMake files which can be used to generate the build/project files you need. CMake is an open-source, cros… --- ## [Direct vtkUnstructuredGrid object inquiry](https://forum.techsoft3d.com/t/direct-vtkunstructuredgrid-object-inquiry/5090)
**Author:** [@hskang](https://forum.techsoft3d.com/u/hskang)\ **Replies:** 1\ **Last updated:** [February 20, 2026, 10:52pm UTC](https://forum.techsoft3d.com/t/direct-vtkunstructuredgrid-object-inquiry/5090 "2026-02-20T22:52:28Z")
I understand that the model and state can be saved as VTU/PVD through VTKLib and VTK Plugin. But what I want to do is obtain the vtkUnstructuredGrid object directly in memory without any physical file I/O. --- ## [The conversion of a CATIA part failed](https://forum.techsoft3d.com/t/the-conversion-of-a-catia-part-failed/5077)
**Author:** [@1224153851](https://forum.techsoft3d.com/u/1224153851)\ **Replies:** 4\ **Last updated:** [February 5, 2026, 11:46am UTC](https://forum.techsoft3d.com/t/the-conversion-of-a-catia-part-failed/5077 "2026-02-05T11:46:56Z")
As shown in the image, this error occurred while converting the CATIA file. --- ## [How to: Detect multi-touch events using a custom operator (HPS)](https://forum.techsoft3d.com/t/how-to-detect-multi-touch-events-using-a-custom-operator-hps/5076)
**Author:** [@simon](https://forum.techsoft3d.com/u/simon)\ **Replies:** 0\ **Last updated:** [February 3, 2026, 11:31pm UTC](https://forum.techsoft3d.com/t/how-to-detect-multi-touch-events-using-a-custom-operator-hps/5076 "2026-02-03T23:31:50Z")
Below is sample code that detect multi-touch events using a custom operator. class MyCustomTapOperator : public HPS::Operator { public: MyCustomTapOperator(HPS::Canvas c) : canvas(c) { tapCount=0; … --- ## [How to: test for double click on custom operator](https://forum.techsoft3d.com/t/how-to-test-for-double-click-on-custom-operator/5068)
**Author:** [@simon](https://forum.techsoft3d.com/u/simon)\ **Replies:** 0\ **Last updated:** [January 31, 2026, 12:08am UTC](https://forum.techsoft3d.com/t/how-to-test-for-double-click-on-custom-operator/5068 "2026-01-31T00:08:53Z")
Below is sample code on how you check for double click mouse event. class MyCustomOperator\_s1 : public HPS::HandlesOperator{public:MyCustomOperator\_s1(HPS::Canvas c) : canvas(c) {}bool OnMouseDown(HPS::MouseState const& … --- ## [How to: Use custom shader to change color of and position of edges](https://forum.techsoft3d.com/t/how-to-use-custom-shader-to-change-color-of-and-position-of-edges/5037)
**Author:** [@simon](https://forum.techsoft3d.com/u/simon)\ **Replies:** 2\ **Last updated:** [January 30, 2026, 7:19pm UTC](https://forum.techsoft3d.com/t/how-to-use-custom-shader-to-change-color-of-and-position-of-edges/5037 "2026-01-30T19:19:42Z")
Below is sample code that uses custom shaders to change color and make a small shift on position of edges. This code was tested on HPS 2025.7.0. Screenshot: Sample code: void CHPSView::OnUserCode2() { // dr… --- ## [How to: Use custom shader to change color of and position of edges (3DF)](https://forum.techsoft3d.com/t/how-to-use-custom-shader-to-change-color-of-and-position-of-edges-3df/5067)
**Author:** [@simon](https://forum.techsoft3d.com/u/simon)\ **Replies:** 0\ **Last updated:** [January 30, 2026, 7:18pm UTC](https://forum.techsoft3d.com/t/how-to-use-custom-shader-to-change-color-of-and-position-of-edges-3df/5067 "2026-01-30T19:18:43Z")
Below is sample code that uses custom shaders to change color and make a small shift on position of edges. This code was tested on HOOPS 3DF 30.40 Sample Code: void CSolidHoopsView::OnExtraSlot4() { static char co… --- ## [WebGL context lost after multiple model switches, followed by slow WebSocket binary streaming](https://forum.techsoft3d.com/t/webgl-context-lost-after-multiple-model-switches-followed-by-slow-websocket-binary-streaming/5050)
**Author:** [@raja.r](https://forum.techsoft3d.com/u/raja.r)\ **Replies:** 1\ **Last updated:** [January 18, 2026, 11:01pm UTC](https://forum.techsoft3d.com/t/webgl-context-lost-after-multiple-model-switches-followed-by-slow-websocket-binary-streaming/5050 "2026-01-18T23:01:56Z")
We are facing an issue with HOOPS Communicator (WebGL) where the WebGL context is lost automatically after multiple model switches (no explicit WEBGL\_lose\_context call from our side). After the context loss: On page … --- ## [Model flickers when calling setNodesVisibility repeatedly](https://forum.techsoft3d.com/t/model-flickers-when-calling-setnodesvisibility-repeatedly/5040)
**Author:** [@raja.r](https://forum.techsoft3d.com/u/raja.r)\ **Replies:** 3\ **Last updated:** [January 4, 2026, 2:05pm UTC](https://forum.techsoft3d.com/t/model-flickers-when-calling-setnodesvisibility-repeatedly/5040 "2026-01-04T14:05:35Z")
I’m facing a flickering issue in HOOPS Communicator whenever I update node visibility. Each time I call the following API, the entire 3D model visibly flickers (looks like a repaint or full re-render): viewer.model.set… --- ## [Can we use hoops for interference checks? What kind of data of the nodes need to be exported?](https://forum.techsoft3d.com/t/can-we-use-hoops-for-interference-checks-what-kind-of-data-of-the-nodes-need-to-be-exported/5018)
**Author:** [@WangFuYuan199](https://forum.techsoft3d.com/u/WangFuYuan199)\ **Replies:** 24\ **Last updated:** [December 30, 2025, 11:14am UTC](https://forum.techsoft3d.com/t/can-we-use-hoops-for-interference-checks-what-kind-of-data-of-the-nodes-need-to-be-exported/5018 "2025-12-30T11:14:56Z")
If hoops does not support static interference detection for models? So, how do we implement this static interference function? For example, how do we export the data of the interference nodes, and which third-party libra… [Next page](https://forum.techsoft3d.com/tag/how-to/21.md?match_all_tags=true&page=1&tags%5B%5D=how-to)