Water Event/Collision Detection

A workaround recently used to detect water & start a splash particle system for plane pontoons on landing:

// Script created by SiRiS Asturias.
// All rights reserved. (c)2005 (Released as OpenSource 12/06/2005)
// Free for use as long as this header stays intact & follows the below guidelines.
 
// This work is licensed under the:
// Creative Commons Attribution-NonCommercial-ShareAlike License.
// To view the full copy of this license, please visit:
// http://creativecommons.org/licenses/by-nc-sa/2.0/
 
integer a; // Idle switch
default
{
	state_entry()
	{
		llSetHoverHeight(0.15,TRUE, 0.5); // Make plane hover
		llSetTimerEvent(0.2); //Land Timer
	}
	timer()
	{
		vector pos = llGetPos() - <0,0,0.2>; //Current position minus offset
		float water = llWater(<0,0,0>); // Water height in the current Sim
		if (a == 1) // If idle
		{
			if (pos.z > water) // Check to see if we are off the water
			{
				llOwnerSay("In the air");
				llSetTimerEvent(0.2); //Took off, start landing timer again
				a = 0; //Set state back to airborne
			}
		}
		else if (pos.z <= water) // Landed on water, trigger particles and wait to leave
		{
				llOwnerSay("Water Landing");
				Water(); // Start splash particle system
				llSetTimerEvent(5.0); // Idle grounded timer
				a = 1; //Set state to water landing
		}
	}
}

This way the only thing it does each timer event is a water to current height comparison on the Z vector.
Could easily be modded to add only calling the llWater function per Sim change for even more efficiency per timer event.
Enjoy!