Using the main navigation page of the HUD.
Instructions on how to control your boat.
Hints on how to sail a boat.
Setting up your sailboat.
It is possible to make your own mesh sails and use the scripts from my sails to bring them to life. Right now you probably have to come talk to me, but I hope this document will be expanded until a good mesh maker can make a working sail without bugging me.
The first rule is DO NOT JUST BUILD A SAIL AND THEN TRY TO CONVERT IT. You will have to build the sail to fit into the limits mentioned below. Some of the limitations were created by me when I wrote the sail scripts, but most of them are limits of OpenSim or the viewer so you must obey these.
To make the sails rotate nicely I always build my sails as a single mesh prim. There are a few exceptions and ways around this, but they may add lag to the server so I avoid that. For example, the furled sail cover can be part of the whole single mesh prim sail, but since it never rotates you could make it a separate prim. A very simple script could listen for the instrument messages that raise and lower the sail and just make the sail cover invisible and visible. I have a script that does this and would gladly give you a copy. The entire sail script can be convinced to do this but it would be laging the server checking for other sail functions. It is possible to split the sail into several separate child prims, put the entire sail script in each and convince the to work at separate times. (How do you convince the script to do this? By carefully making lists of faces as described below). This adds extra vertexes to the sail and adds another script to the build, two things that I perfer to avoid.
A mesh prim is only allowed to have 8 “materials” or faces. To animate the sails I make each different part of the sail a different material and this rapidly uses up all 8 materials. To make the sails rotate smoothly, I have to use one material to make a “counterweight” on each sail. So now you only have 7 left. I build the sails curved left and right, so that doubles the number of materials needed. My scripts allow the sails to be full or reefed half way, and that doubles the number of materials again. I think you should try to keep your builds small to be kind to the system, so if your sail has a boom folded up or furled shape, you should only have those once in the prim and share them with the other parts. For example, a Bermuda sail could have a full sail left and right, a reefed sail left and right, a folded up sail, a boom and a counterweight. That is 7 materials and we are about out. When the sail is up, the boom is also visible. When the sail is reefed the folded up sail is also visible to create the illusion of half the sail tied to the boom. When the sail s furled the boom and folded sail are the only materials visible. If I had more materials, I would ad a pair of wrinkled sails to show the sail fluttering when not trimmed well. Then I need two more for fluttering the reefed sail. A separate material for the half-folded sail when reefed would be nice.
My solution to this for for-and-aft sails was to put an extra face, a single quadrangle, exactly the same distance in front of the sail as the back end of the boom. this makes a Bermuta sail to rotate exactly around the edge where it is placed along the mast. Note that for hysterical reasons, the fore-and-aft sails are made with their local Y axis pointing opposite from the boom. So when the sail is hanging directly behind the mast, the Y axis points forweard on the boat, and the counterweight is in front of the mast. The local Z axis points up along the leading edge of a Bermuda sail, and the local X azis points sideways when the sail is hanging directly behind the mast. For Lateen, Lug and Gaff, you must choose the location where you want the sail to attach to the mast, and balance the counterweigh forward from that point. So parts of the sail can be in front of the mast when the boom or yardarm is hanging straight back behind the mast.
My solution for jib sails was to have the local Z axis runs along the halyard (the wire or rope that the leading edge of the jib rotates around). The local X axis points sideways when the jib is hanging straight back from the halyard. The local Y axis is pointing up and forward, the opposite direction that the sail is hanging. The counterweight to make it rotate nicely around the halyard must be placed along the positivwe Y axis, a distance equal to the distance that the far corner hangs.
My solution for square sails was to have the local Z axis pointing up paralell to the mast. The X axis is pointing forward when the sail is perpendicular to the boat (as when the wind is directly behind the boat). The local Y axis is pointing paralell to the yardarm. The counterweight has to be far enough behind the sail to "counteract" the curved shape of the full square sail. I like to place it a little farther back so the yardarm rotates a little in front of the mast. This prevents the yardarm from passing through the mast and is a pretty realistic placement.
lfurled=5,2,0 lreeflft=6,2,0 lreefrgt=7,2,0 lfulllft=3,0 lfullrgt=4,0lfurled=5,2,0
When reefed on the left side of the mast, the face that looks like a sail on the left is number 6. This face also includes a copy of the yardarm at the top of the sail. 0 is the boom, which you will see is shared by all the states of the sail. I asked for face number 2, which is the folded sail, to show half of the sail folded up on top of the boom. This is actually the same as the whole sail folded up, but without the yardarm on top of it.
When the sail is reefed and the wind blows it onto the right side of the boat, the only difference from the left side is face 7 instead of face 6.
Face number 3 is the full sail on the left side of the boat. It has a yardarm on top so all it needs is to have the boom (0) visible at the same time.
When the wind blows the full sail over to the right side, the only difference is face 3 is replaced by face 4.
lfurled=0 lreefl=0,3 lreefr=0,4 lfulll=1 lfullr=2 lnotex=0,5My furled jib sail is face number 0. The reefed sail left (3) and right (4) are displayed with the furled sail so it looks like part of the sail has been rolled or tied up. The full sail on the left (1) and right (2) are visible just by themselves. The "lnotex" line is a list of faces that don't change textures with damage. 0 is the furled sail, and 5 is the counterweight.
lfurled=[4,7]; //which faces must be visible when furled lreefed=[4,5,7]; //which faces for reefed lreeff1=[4,5,7]; //reefed flutter 1 lreeff2=[4,6,7]; //reffed flutter 2 lfull=[1,7]; //full sail lfullf1=[2,7]; //full flutter 1 lfullf2=[3,7]; //full flutter 2 lnotex=[0,7]; //which faces don't have damage textures
Sails need to have a front and a back surface to be visible from all angles in OpenSim. But sails do not need to be “solidified”. They do not need to have quadrangles made to stitch the left and right sides together. A sail can just be two separate sheets of quads or triangles, (both sides part of the same material), very close to each other, with normals facing in opposite directions.