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- /*
- * flyhelp.h: generated automatically from file "flyhelp"
- *
- * to modify, edit "flyhelp" and type "make flyhelp.h"
- */
- "\n\
- This geomview external module lets you fly through the tesselation of\n\
- hyperbolic space by a right-angled regular dodecahedron which appeared\n\
- in the mathematical animation \"Not Knot\" produced by the Geometry\n\
- Center. You can either pick a pre-computed flight path or fly around\n\
- interactively.\n\
- \n\
- All 30 edges of the dodecahedron are white except the three pairs of\n\
- edges colored green, blue and red corresponding to the three loops of\n\
- the Borromean rings. Every face of the dodecahedron has exactly one\n\
- non-white edge, so we can color the face by this color.\n\
- \n\
- All flight paths begin and end at the center of a green face. There\n\
- are three other green faces: one adjacent to this one, at right\n\
- angles along the green beam; and a pair which border the other green\n\
- beam, on the other side of the dodecahedron.\n\
- \n\
- The light blue \"Direct\" path is the simplest to understand:\n\
- we go straight through to the green face directly opposite from the\n\
- original face.\n\
- \n\
- The yellow \"Quarter Turn\" path, which goes to the adjacent green face,\n\
- simply circles around the green axis which the two faces share.\n\
- \n\
- The \"Full Loop\" path is also yellow: it repeats this quarter turn four\n\
- times so that we start and finish in the same place. The three other\n\
- paths just jump back to the starting place when they reach the end.\n\
- \n\
- The magenta \"Equidistant\" path, which goes to the other green face\n\
- which doesn't border the original face, is the most interesting. It\n\
- follows a so-called equidistant curve: in this case, one that is\n\
- equidistant to the red axis that connects the two green faces in\n\
- question. This curve is like a parallel line in Euclidean space: it\n\
- stays a constant distant from the red axis, but it's not a geodesic in\n\
- hyperbolic space.\n\
- \n\
- In the small 3D diagram window, you can use the left mouse button to\n\
- spin around a dodecahedron with colored coded flight paths as\n\
- mentioned above. It's easier to see what's going on in the Euclidean\n\
- diagram, while the hyperbolic version is more similar to what you see\n\
- in the flythrough.\n\
- \n\
- You can either choose one of four flight paths through the tesselation\n\
- or stop the automatic flight by hitting the \"Stop\" button and fly\n\
- around yourself. For interactive flight, hit the \"Cam Fly\" button on\n\
- the geomview Tools panel: then dragging the mouse with the middle\n\
- button down moves you forwards or backwards, and dragging with the\n\
- left button down is like turning your head. When you hit \"Go\", the\n\
- automatic flight will continue.\n\
- \n\
- You can choose one of four tesselation levels: level 0 is a single\n\
- dodecahedron, level 1 adds a layer of 12 dodecahedra (one for each\n\
- face of the original dodecahedron), level 2 tesselates two layers\n\
- deep, and level 3 has three layers. The more layers you have the\n\
- slower the update rate: level 3 is glacially slow, but each frame\n\
- looks pretty impressive. You can change the size of the dodecahedra\n\
- with the \"Scale Dodecahedra\" slider: at 1.0 they fit together exactly.\n\
- The \"Steps\" buttons control the smoothness of the flight path: you can\n\
- set the number of steps to 10 (jerky but fast), 20, 40, or 80 (smooth\n\
- but slow).\n\
- \n\
- \n\
- Authors: \n\
- Charlie Gunn (geometry and flight paths) gunn@geom.umn.edu\n\
- Tamara Munzner (interactive interface) munzner@geom.umn.edu\n\
- Stuart Levy (3D diagram) levy@geom.umn.edu\n\
- \n\
- Copyright (c) 1992\n\
- The Geometry Center\n\
- 1300 South Second Street\n\
- Minneapolis, MN 55454\n\
- email: software@geom.umn.edu\n\
- \n\
- Available free via anonymous ftp from geom.umn.edu\n\
- \n\
- You can redistribute and/or modify this program according to the terms\n\
- of the the GNU Emacs Public License.\n\n"
-