¶ 3D Window
3D window (or 3D view - the two names are interchangeable in terms of this wiki) is one of the main working areas in PCS. In the 3D window, the user can visualise the part of the point cloud selected and loaded from the 2D window using the clip frame toolbar. In the 3D window, the user can move “freely” with the mouse if not inside a command and hold the CTRL button if inside the command. The cloud can be rotated by holding down the left mouse key and moving the mouse around, zooming in and out using the scroll and panning using the scroll mouse button. The centre of the viewpoint can be re-assigned with a double-left-click, which is snap-sensitive, which means that the respective snap mode shall be turned to change the rotation centre. See the detailed explanation below.
The 3D window - by default - can handle points up to 256 million. If the user tries to load more points to the 3D window, the software will automatically clip up to 256 million - even if the hardware could handle more. In these cases, the cloud might look incomplete, and visual tiles might be missing. If this happens, please reload a smaller area using the clip frame. The software will load all points into the 3D view, so once the loading is done, no more loading will be performed; the 3D view will be fluent with all loaded points. For a fluent 3D experience, the software stores the points in the GPU for the 3D window.
The 3D window hosts the 3D marker. We strongly recommend reading the 3D marker article to properly understand what it is, how it's activated and what it does.
The 3D window has its own set of toolbars and hotkeys. The window can be docked/undocked.
¶ Understanding the 3D navigation
The key to effectively using the software is to understand and handle the 3D navigation properly in the 3D window. Operators capable of fluently handling this view are way more effective in the production environment than those using section views for extraction features.
The key is the rotation centre, which will be set to the centre of the mass after loading the cloud to the 3D view. The default snap setting is point cloud snap if the user is outside a command. Using this snap mode, the user can double-left-click anywhere in the cloud, and the selected point becomes the rotation centre. If the user uses a command, holding the CTRL button will allow the user to navigate the cloud and re-assign the rotation centre. If the rotation centre is not commonly assigned to a new location, the view might “become odd”. This means that the user might be moved around the centre, zoom in or out too much, and so on. If the user encounters odd movement in the 3D view, it is most likely the rotation centre is misplaced or marked to a location which is too close or too far from the camera centre point. In these cases, a new rotation centre point shall be picked. This issue is prevalent for beginner users.
We would also like to raise the user's attention again for snap modes. It is also a common issue that users - accidentally or willingly - turn off the point cloud snap outside of the command, or if they are inside a command, they use a tool which does not require point cloud snap. If the point cloud snap is turned off, the user cannot change the rotation centre to any point cloud point. The rotation centre can be assigned to vector points or to point cloud points. The “free point snap” and auxiliary plane snap are unusable when changing the rotation centre.
The best practice for navigating in the 3D environment is to change the rotation centre frequently as every 2nd or 3rd action of the operator shall be this. To move effectively in a 3D environment, place the rotation centre where the user looks with their eye's axis. If the user always picks the point where they look, it will be easy to handle the 3D view. It is also considered best practice if a linear object is checked/extracted; the view shall be perpendicular to the object, and panning shall be used. This is a fast and effective way to navigate over linear objects. Trying to navigate on a linear object by changing the rotation centre and zooming in will consume way more time.
The rotation centre can be visualised in the 3D key.