Only respond to touch event if agent is stood infront of prim

[BlackMagi Darkwatch]

Hi

Scenario

Agent behind door, cams around the wall and touches the lever and opens the door from the inside. What I would like to achieve is to stop this from happening, in otherwords the agent must be stood infront of the door switch.  I will have no control over the final rotation of the building so I need to take this into account also (and I suck big time at rotations!).

This is what I have at the moment but the float result is always given as postive number so not much help there.

    touch_end(integer total_number)
    {
        if (llDetectedTouchFace(0) == face_number)
        {
            llOwnerSay("Correct face touched...");
            
            //Now to check if the Agent is infront of the prim
            vector my_position = llGetPos();
            vector av_position = llDetectedPos(0);
            
            float test = llVecDist(av_position, my_position);
            llOwnerSay((string)test);   
        }
    }

 I also tried breaking down x,y portions of the vectors but as soon as I rotate my linkset then the results are skewed again.

 If anyone can offer some ideas that would be great

Black

 

[Zen Zeddmore]

I don't think you will acheive the security you desire this way. You CAN implement using the function that recognizes where on a prim a touch is implemented to make a combination lock. It can also recognize the avatar doing the touching so that perhaps anyone entering the proper pass code would not be ejected from the land.

[Dora Gustafson]

For a box prim, each face has one normal
namely: Forward, Left, Up,  -Forward, -Left and -Up

From the top of my head face 0 has Up and face 5 has -Up

Knowing the normal, the prim position and the avatar position
you can use the vector dot product to tell on which side of the prim the avatar is

I will expand your example to do that for face 0:

touch_end(integer total_number){    if (llDetectedTouchFace(0) == 0)    {        llOwnerSay("Correct face touched...");        //Now to check if the Agent is infront of the prim        vector my_position = llGetPos();        vector av_position = llDetectedPos(0);        float test = llVecDist(av_position, my_position);        llOwnerSay((string)test);	float vectorProduct = llRot2Up( llGetRot())*( av_position - my_position);	if ( vectorProduct > 0.0 ) llownerSay("The avatar is in front of the prim");	else llownerSay("The avatar is NOT in front of the prim");    }}

 Note that this is for face 0 exclusively:smileysurprised::smileyvery-happy:

[BlackMagi Darkwatch]

Perfect, thank you Dora - I did have a flash of perhaps llCastRay or llSensor but this solution is much clearer and leads me off now to read about prim normals & llRot2Up

 

Black

[Dora Gustafson]

Great!
I realize now that you may get there even easier by using llDetectedTouchNormal for llRot2Up

:smileysurprised::smileyvery-happy:

[BlackMagi Darkwatch]

I think the code snippet supplied about Rot2Up is great and works whichever way I rotate the prim within the linkset - there is another optimisation listed on the webpage for llRot2Up so am posting my complete snippet here - this way I can find it in the future!

 

    touch_end(integer total_number)    {        if (llDetectedTouchFace(0) == face_number)        {                vector      my_position = llGetPos();            rotation    my_rotation = llGetRot();            vector      av_position = llDetectedPos(0);            string      av_name     = llGetDisplayName(llDetectedKey(0));                        //Check if the Agent is infront of the prim            float vectorProduct = (<0.0,0.0,1.0> * my_rotation) * (av_position - my_position);                        if ( vectorProduct > 0.0 ) {                //Check to see if the agent is close enough to operate our lever                if (llVecDist(my_position, av_position) > 2.5) { //FALSE                    llWhisper(0, av_name + " Message: To far away");                } else { //TRUE                    llOwnerSay("Message: None: Send Link Messages");                }            } else { //AV is not infront of the prim - let them know                llWhisper(0, av_name + " Message: Can't open");            }        }    }

 

Note: In this snippet I also check to see how far away the toucher is - might not be so elegant but it works

 

Thank you to all who replied.

Black