Passage Wall Modeling

3D Passage Wall Modeling

COMPASS is capable of using the Up, Down, Right, and Left data to generate models of the passage walls. Compass has the ability to model passage walls in more than a dozen different ways.

3D Modes

Compass can model passage in both 2D and 3D modes. The 2D modes are generally used for creating paper maps, to assist with cartography and for publication. Click here for information on the 2D modes. The 3D modes creates full 3D models of the passages that can be rotated and view from any angle.

3D Modeling Engine.

Over the years Compass has used a variety of techniques for generating realistic cave passage models. Unfortunately, each new improvement did not always get integrated back into other parts of Compass. To deal with this problem, Compass now has an integrated 3D Modeling Engine that produces cave passage models for all Compass programs. This means that all aspects of Compass, even the export options, now produces very realistic passage models. Here is demonstration of the passage generation process:

Passage Outlines.
The first step in the process is convert the left, right, up and down measurements into passage outlines. As you can see below, choosing the right outline shape determines the accuracy of the model.

Square.	Diamond.	Octagon.
This shape is the easiest to generate but is not very accurate. You can't even tell that the passage is asymmetrical.	This shape is more accurate. At least you can see that the passage is asymmetrical	This shape preserves the asymmetry, but is more rounded, cave-like shape.

Step1. This image shows a simple curved passage with square passage outlines drawn around the survey shots.

Step 2. Here we have changed the passage outline to octahedral.

Step 3. In this step the end of each passage segment has been joined to its immediate neighbors.

Step 4. In this step, additional passage segments are added, smoothing transitions between different size passages

Step 5. At this point CaveX takes over and adds solid faces, lighting and shadowing.

Step 6. Finally, CaveX smoothes the surfaces using special techniques such as gouraud shading.

Viewer Modes

This image shows a more complex set of passages displayed with the Standard Compass Viewer. More advanced passage 3D modeling is done with CaveX.

Stereo 3D Polygon Mode

This image requires red/blue stereo glasses to view. It shows the 3D modeling viewed in stereo. This means that the actual passage walls can seen in stereo.

CaveX Full 3D Visualization Options

Transparency Option.

CaveX's new transparency option allows you to see the interiors of passages to view the stations and survey shots. Here the shot lines are displayed as blue lines and the stations as yellow squares. The transparency option is very handy for viewing intertwined passages and complex three-dimensional caves.