Google SketchUp may be the best free way to display information about caves that is available. From showing the cave location on Google Earth to displaying a complete 3D model with photos, profiles, sketches, notes and anything else you wish to display. With the turning off and on of layers you can select items you wish to display or study. The model can be rotated in any direction in real time and the landscape can be placed right over the cave.

Drawing

Editing and free hand drawings can be created. Google SketchUp has many of the common drawing features of other drawing programs that are expensive.

The Line feature is very simple to use with quick color or textures filled in automatic when you close a face.

With the Arc feature you select two points and then adjust the curve.

The Freehand allows tracing of previous drawings or creating new ones.

Of course you can select the color, texture and layer. I have not been able to find a way to change the line width. However when you turn on the Depth Cue feature under View/Edge Styles, the lines become thinner in the distance and thicker for close items. If a line is drawn going off into the distance such as telephone lines they will decrease in width the further you are in the back ground.

You can also create circles, rectangles, and polygons in the three dimensional space. Then use the Push/Pull tool to give them depth. For example a passage could be drawn in the plan or top view, then pushed to give it the correct height. Use the tape measure to check the distance and add dimensions. To get more realistic delete the top of the passage and use the fill tool to paint the floor of the passage with rocks. Then apply sand or dirt to the sides and you have a realistic 3D passage the you can view from any angle.

Import

You can import most any type of file and position it in the drawing. It is easy to resize pictures and reposition them. By turning on X-Ray you can see all of the items and how they relate to each other. I am using the CAPS cave mapping software to export DXF files for survey lines as well as complete 3D wall models and then importing them into Google SketchUp.

By importing a drawing section in plan and another in profile, you can position them over the survey line. Scale them to match and position them at right angles for a clear understanding of the cave passages.

Printing

Any view you create on the screen, you can print to the printer. This is perfect for surveys in progress. By printing to PDF files using the free PDF995 tool you can distribute maps.

Conclusion

There are many other features such Look Around and camera positions and animations that I have yet to experiment with. I believe that Google SketchUp will become my drafting tool of choice for all of my projects in the future.