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- ' LA OROYA Software, 1993.
- ' ------------------------
- ' Document for the Yachting programme, by Stephan Scholz
- ' The programme >>> Yachting <<< is public domain.
- '
- ' C O M M E N T S :
- ' =================
- '
- ' This programme intends to show the relationship between wind speed
- ' and direction, sail-boom angle and yacht heading and speed, turning
- ' this into a playable simulator game.
- '
- ' On loading, a screen showing a circular wind graph appears:
- ' The darker blue zone shows the maximum traveling speeds for modern
- ' yachts, according to the direction the wind is coming from. The
- ' light blue area shows speeds with raised spinnaker for rear winds.
- '
- '
- ' Improvements on the first version:
- ' ----------------------------------
- '
- ' - The rather messy printed numbers for the yacht speed have now
- ' been converted into a speedometer dial, and the heading is now given
- ' by a smooth mini-scrolling compass. The dashboard now boasts the name
- ' of the programme, and the pseudonym logo "La Oroya" - taken from a
- ' mountain-town in the Andes I had always wanted to visit but never
- ' got round to.
- '
- ' - Some calculations have been taken out of the main loop and some
- ' numbers converted into variables - scrounging milliseconds...
- '
- ' - Also, compiling it did seem to improve things a bit, thank heavens!
- '
- ' - The background scrolling speed has been improved, making the whole
- ' programme perform more smoothly. The culprit was that I was copying
- ' the whole background instead of a third of the strip! My sincere
- ' apologies for any hassle caused.
- '
- ' - The race is done in three separate laps. Before starting, you can
- ' point your yacht in the desired direction, i.e. depending on the wind
- ' angle, you can choose your course by clicking on the rudder chevrons
- ' "<" or ">". Press space to start the lap. You will have to keep your
- ' space bar down a few seconds, as the routine only reads the keyboard
- ' between waves, when the horizon is up. This part also lets you quit
- ' by pressing "Q".
- ' You will win if you've won two out of three laps,
- ' Wind direction changes a bit from lap to lap.
- '
- ' Once you've started the radar-scanner indicates a green dot near the
- ' buoy you should be heading for.
- '
- ' - An ocean sound, changing with speed, adds atmosphere...
- ' If you are stealing the other's wind this sound will change into a
- ' swishing sound. If your wind is being stolen, your speedometer will
- ' tell you, and the ocean sound becomes quieter.
- '
- ' - The creacking noises are when you move your sail or raise or lower
- ' the spinnaker. The latter now takes a few seconds - 5 creaks!
- '
- ' - Collisions are accompanied by a violent crashing sound, and you
- ' are spun off course violently!
- '
- ' Future versions might have a damage control.
- '
- ' Possible improvements :
- ' -----------------------
- '
- ' - Instead of having an automatic competitor getting sailing speeds
- ' from a wind angle table called AUTOS in the SAILDATA procedure,
- ' one could have a version where a second computer were linked up
- ' and a second operator controlled the other ship in the same fashion
- ' as Object 0 (the viewpoint - your ship, in effect) is controlled.
- '
- ' - One could also set up a championship routine, perhaps with
- ' different models that behaved differently under different weather
- ' conditions, and hall of fame to enter one's name.
- '
- '
- ' Further comments:
- ' -----------------
- '
- ' A mathematical co-processor would probably be a grateful additive
- ' to use with this trigonometry and decimal-places ridden programme !!!
- '
- ' An accellerator is also convenient, giving faster screen update and
- ' smoother movement, as the processor has a lot of work with all the
- ' calculations. I have tried to keep these to a minimum, using data
- ' tables as much as possible, and I haven't included a jib (the
- ' fore-sail), or the turning effect that can be achieved by letting
- ' out or bringing in only one of the two sails. A trigonometrical
- ' drift calculation for each sail is necessary, similar to the
- ' propulsion calculation (which would have to be done for each sail
- ' too), so you can guess what will happen without an accellerator!
- ' Hence also the lack of lateral drift. Normally, depending on your
- ' speed, your true course can drift upto 5 degrees leeward of your
- ' heading with winds forward of the beam. This sideways drift could
- ' be included, but would slow down the programme and make it harder
- ' to sail than it already is.
- '
- ' So at present the YACHTING programme supposes that your course is your
- ' heading, and this is kept constant unless you move your rudder, i.e.
- ' you have a jib that someone is attending to, thus maintaining the ship
- ' balanced and on course. This way you are spared the never-ending rudder
- ' operations necessary to keep single-sailed craft on course, or balancing
- ' the jib and the mainsail all the time.
- '
- '
- ' INSTRUCTIONS ON HOW TO SAIL:
- ' ----------------------------
- '
- ' On the starting line, choose which direction to face when you start.
- ' Take care you are not heading squarely into the wind - you won't get
- ' any speed at all! Click on the rudder chevrons "<" and ">" to rotate.
- '
- ' Your yacht will move forward if the wind catches the sail. In the
- ' main navigation instrument in the lower center, there is a light blue
- ' line indicator in the green ring, indicating where the wind is coming
- ' from, relative to your ship. If you turn your ship, this line will
- ' turn, moving round in the green ring as the wind angle changes with
- ' respect to your ship. This line is the apparent wind, which will move
- ' forwards as you gather speed, so you will have to adjust the sail boom
- ' accordingly, to maintain optimum sail angle with respect to the wind.
- '
- ' Inside the green circle, is a drawing of your ship. You have a boom
- ' indicator which can be moved outwards on inwards by clicking on the
- ' chevrons "^" and "v". The boom will be light blue if optimum sail
- ' efficiency is achieved, although this is not possible for very rear
- ' winds. It will be green if the wind is pushing the sail - meaning less
- ' efficiency, as no laminar flow is being achieved. Laminar flow happens
- ' happens with a wind incidence of 10 to 25 degrees on the sail, as a
- ' suction force is ceated, similar to an aircraft wing.
- '
- ' If the boom indicator is grey, however, it means the sail is
- ' flapping loosely in the wind, and you are getting no push at all.
- ' In this case you should draw in the boom, clicking on the red "v"
- ' to the right of the instrument, until the boom slowly moves in.
- ' It may take a while to start moving if it has been out far - all
- ' that loose rope has to be collected..!
- '
- ' If you are headed straight into the wind, i.e. the blue wind line
- ' is near the nose of your ship, taking in the boom will be to no
- ' avail, and you will have to turn the yacht right or left, clicking
- ' on the red ">" or "<" below the instrument - the yellow line is your
- ' rudder. Turning will be very sluggish indeed if you have no speed, so
- ' DON'T turn into the wind without speed ! - i.e. for tacking - doing
- ' a zig-zag course for a route against the wind.
- '
- ' Even if your boom indicates laminar flow, i.e. it is light blue,
- ' there is a certain optimum position within the 10-25 degree angle
- ' of incidence range, which is 22 degrees. Move the boom in or out
- ' just a little to get this best push! Your speed will tell you.
- ' Of course, depending on where the wind is coming from your optimum
- ' speed will vary. There are no random factors affecting wind, boom
- ' or steering. It's difficult enough without those!
- '
- ' If your competitor is too fast for you you might like to reduce
- ' the A#*2.1 value to A#*1.7 in the SAILDATA procedure in the READ A#
- ' instruction just before the AUTOS data section. (These values give
- ' the speed for the automatic ship, based on the wind graph data table).
- '
- ' Your own ship's speed table is different: Your speed depends on wind
- ' incidence angle on the sail - this table is SAILS data section, and
- ' is complemented by the SPINNAKER data section further on). Don't change
- ' these, as it will probably ruin your yacht's performance. Your
- ' adversary's ship and your own ship behave differently:
- ' Yours is a bit faster and sails closer to the wind, although your
- ' competitor accellerates and turns faster, and runs very well before
- ' the wind.
- ' You will find it very useful to get round the other boat on the
- ' windward side, steal the other's wind. Watch out you don't get on
- ' the leeward side - you'll lose your speed.
- '
- ' If you are heading into the wind you can do so only at an angle.
- ' Watch your speed indicator, which is to the left of the main
- ' instrument. With a 12 knot wind your yacht (which is very
- ' efficient and fast and behaves somewhat like a catamaran even!),
- ' will sail forwards at about 8 knots with a real wind coming from
- ' the side (90 deg.) and 3 or 4 knots heading into the wind at angles
- ' of 40 or 45 degrees.
- '
- ' The real wind angle cannot be "seen" from your yacht, only the
- ' apparent wind, which changes with your speed. Should you want to
- ' see the real wind on the wind instrument, there is a line you can
- ' use: Draw H(WW,3),H(WW,4) to H(WW,5),H(WW,6). Write this in, just
- ' below Draw H(AWA,3),H(AWA,4) to H(AWA,5),H(AWA,6) in the main loop.
- ' You may find it interesting to see how your ship's apparent wind
- ' behaves with respect to the real wind, depending on your speed.
- '
- ' If you are sailing with rear winds, your boom should be let out as
- ' far as possible, clicking on the red "^", and you can achieve a speed
- ' of about 4 kts. without spinnaker.
- '
- ' If you click on the little box inside the speed instrument, this will
- ' slowly raise or lower the spinnaker. The symbol in the box will tell
- ' you if it is stowed (v), raised (^) or being raised or lowered (*).
- ' The spinnaker gives you increased push for any real winds coming from
- ' anywhere behind the beam (90 to 180 degrees). If you raise the spinnaker
- ' with forward winds, this will bring you to a halt. With a spinnaker, the
- ' maximum yacht speed, just over 10 knots, will be achieved with a real
- ' wind at 135 degrees. If at 180 degrees, speed is about 6 knots.
- '
- ' For the moment, the program has a fixed real wind speed of 12 knots
- ' but the wind direction is random.
- '
- ' Watch out with hitting the buoys or the other ship! It will send you
- ' spinning violently off course! It may happen that the other one will
- ' hit you too, so watch out! Keep an eye on the radar-scanner. The blue
- ' dot tells you where the other ship is. You are the yellow dot. Even if
- ' you or the other boat leave the boundary of the scanner, a dot remains
- ' in the blue fringe on the margin to tell you in what direction that
- ' ship is. The red dots are the three buoys, and a little green dot
- ' near one of the buoys will indicate which buoy you should be heading
- ' for.
- '
- ' Starting off, sail for the north buoy, which lies ahead and to the
- ' left of where you are, (the other ship will set off, so you can
- ' follow it - you are faster, and can overtake it).
- ' Sail round the north buoy, (don't collide with it), and as soon as
- ' you hear the bell, or you see the green dot on your scanner disappear
- ' from the north buoy, you can set course for the Southwest buoy, and
- ' then the East one, which is the "finish line".
- '
- ' To keep track of the route, the programme has to detect if you've
- ' entered an area 5000 VLU's in diameter which touches the north buoy
- ' on the north side. The west buoy also has such an area to the south west.
- ' During the race, rounding the buoy without hitting it is easy enough.
- '
- ' IMPORTANT:
- ' If you don't enter these areas, i.e. if you give the buoy too wide a
- ' berth, the programme can't detect that you have rounded the buoy, and
- ' won't finish the race - the other ship will continue sailing past the
- ' last buoy ad-infinitum... During the race it is easy enough to round
- ' the buoys close enough without danger of hitting them.
- '
- ' The finish "line" is an area 5000 VLU's in diameter, touching the
- ' last buoy on the south east (This is the buoy you started the race from).
- ' You can enter the finishing area from any direction south of the buoy.
- ' The program detects who is first to enter this area and will tell
- ' you if you've won the lap - and the times you've bumped into something.
- '
- '
- ' Have fun!
- '
- ' Stephan Scholz
-