Best of Show: Carl Banks Penn State Department of Aerospace Engineering 232 Hammond Building University Park, PA 16802 USA http://www.personal.psu.edu/users/c/w/cwb129/ Judge's Comments: To build: make banks To use: cat horizon.sc pittsburgh.sc | ./banks What can we say? It's a flight sim done in 1536 bytes of real code. This one is a real marvel. When people say the size limits are too tight, well, we can just point them at this one. This program really pushes the envelope! The provided Makefile should work; you will need an X-ish system, and a select() system call. More on building in the author comments. NOTE: On some systems the original entry did not correctly display the altitude and airspeed. These problems have been fixed. One can still build the original program by: make banks.orig Selected Author's Comments: You have just stepped out of the real world and into the virtual. You are now sitting in the cockpit of a Piper Cherokee airplane, heading north, flying 1000 feet above ground level. Use the keyboard to fly the airplane. The arrow keys represent the control stick. Press the Up Arrow key to push the stick forward. Press the left arrow key to move the stick left, and so on. Press Enter to re-center the stick. Use Page Up and Page Down increase and decrease the throttle, respectively. (The rudder is automatically coordinated with the turn rate, so rudder pedals are not represented.) On your display, you will see on the bottom left corner three instruments. The first is the airspeed indicator; it tells you how fast you're going in knots. The second is the heading indicator, or compass. 0 is north, 90 is east, 180 is south, 270 is west. The third instrument is the altimeter, which measures your height above ground level in feet. -------- Features -------- * Simulator models a Piper Cherokee, which is a light, single-engine propeller driven airplane. * The airplane is modeled as a six degree-of-freedom rigid body, accurately reflecting its dynamics (for normal flight conditions, at least). * Fly through a virtual 3-D world, while sitting at your X console. * Loadable scenery files. * Head-up display contains three instruments: a true airspeed indicator, a heading indicator (compass), and an altimeter. * Flight controls may be mapped to any keys at compile time by redefining the macros in the build file. Nice if your keyboard doesn't have arrow keys. (Or if you still use vi. :-) * Time step size can be set at compile time. This is useful to reduce flicker on network X connections. (But be careful: step sizes longer than about 0.03 seconds tend to have numerical stability problems.) * Airplane never stalls! * Airplane never runs out of fuel! * Fly underground! * Fly through buildings! ------- Scenery ------- Each of the *.sc files is a scenery file. The simulator program reads in the scenery from standard input on startup. You may input more than one scenery file, as long as there are less than 1000 total lines of input. Here is a brief description of the scenery files: horizon.sc -- A horizon, nothing more. You will probably always want to input this piece of scenery. mountains.sc -- An alternate horizon; a little more mountainous. pittsburgh.sc -- Scenery of downtown Pittsburgh. The downtown area is initially located to your right. bb.sc -- Simple obstacle course. Try to fly over the buildings and under the bridges. pyramids.sc -- Fly over the tombs of the ancient Pharaohs, in this (fictitious) Egyptian landscape. river.sc -- Follow a flowing river from the sky. A few examples of how to input scenery: cat horizon.sc pittsburgh.sc | ./banks cat mountains.sc bb.sc | ./banks cat mountains.sc river.sc pyramids.sc | ./banks You can simulate flying through a cloud bank as well: ./banks < /dev/null You will usually want at least a horizon, though. The format of scenery files is simple, by the way. They're just a list of 3-D coordinates, and the simulator simply draws line segments from point to point as listed in the scenery file. 0 0 0 is used to end a series of consecutive line segments. Note that in the coordinate system used, the third coordinate represents altitude in a negative sense: negative numbers are positive altitudes. I'm sure you'll be making your own scenery files very soon!!! ---------------------------- Alternate Build Instructions ---------------------------- Several options must be passed to the compiler to make the build work. The provided build file has the appropriate options set to default values. Use this section if you want to compile with different options. To map a key to a control, you must pass an option to the compiler in the format ``-Dcontrol=key''. The possible controls you can map are described in the table below: Control Description Default Key ------- ------------------------- ----------- IT Increase throttle XK_Page_Up DT Decrease throttle XK_Page_Down FD Move stick forward XK_Up BK Move stick back XK_Down LT Move stick left XK_Left RT Move stick right XK_Right CS Center stick XK_Enter Values for the possible keys can be found in the X Windows header file . This file is most likely a cross-reference to another header, . You must map all seven controls to keys at compile time, or the compilation will fail. For example, to map Center Stick to the space-bar, the compile option would be ``-DCS=XK_space''. To set the time step size, you must pass the following option to the compiler: ``-Ddt=duration'', where dt is literal, and where duration is the time in seconds you want the time step to be. Two things to keep in mind when selecting a time step. Time steps that are too large (more than about 0.03) will cause numerical stability problems and should be avoided. Setting the time step to be smaller than your clock resolution will slow down the simulator, because the system pauses for more time than the simulator expects. The best advice is to set time step size to your system timer resolution. Try a longer period if you're getting too much flicker.