Camera Sync

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Camera sync allows for two users to synchronize their cameras, for use by builders in joint projects or in tutorials and demonstrations.


Camera Tween - Smoothly adjusts the position and rotation of the camera over a given number of steps: <lsl>camTween(rotation camRot_origin, vector camPos_origin, rotation camRot_target, vector camPos_target, float steps) {

   //Keep steps a float, but make sure its rounded off to the nearest 1.0
   steps = (float)llRound(steps);
   
   //Calculate camera position increments
   vector posStep = (camPos_target - camPos_origin) / steps;
   
   //Calculate camera rotation increments
   //rotation rotStep = (camRot_target - camRot_origin);
   //rotStep = <rotStep.x / steps, rotStep.y / steps, rotStep.z / steps, rotStep.s / steps>;
   
   
   float cStep = 0.0; //Loop through motion for cStep = current step, while cStep <= Total steps
   for(; cStep <= steps; ++cStep)
   {
       //Set next position in tween
       vector camPos_next = camPos_origin + (posStep * cStep);
       rotation camRot_next = slerp( camRot_origin, camRot_target, cStep / steps);
       
       //Set camera parameters
       llSetCameraParams([
           CAMERA_ACTIVE, 1, //1 is active, 0 is inactive
           CAMERA_BEHINDNESS_ANGLE, 0.0, //(0 to 180) degrees
           CAMERA_BEHINDNESS_LAG, 0.0, //(0 to 3) seconds
           CAMERA_DISTANCE, 0.0, //(0.5 to 10) meters
           CAMERA_FOCUS, camPos_next + llRot2Fwd(camRot_next), //Region-relative position
           CAMERA_FOCUS_LAG, 0.0 , //(0 to 3) seconds
           CAMERA_FOCUS_LOCKED, TRUE, //(TRUE or FALSE)
           CAMERA_FOCUS_THRESHOLD, 0.0, //(0 to 4) meters
           CAMERA_POSITION, camPos_next, //Region-relative position
           CAMERA_POSITION_LAG, 0.0, //(0 to 3) seconds
           CAMERA_POSITION_LOCKED, TRUE, //(TRUE or FALSE)
           CAMERA_POSITION_THRESHOLD, 0.0, //(0 to 4) meters
           CAMERA_FOCUS_OFFSET, ZERO_VECTOR //<-10,-10,-10> to <10,10,10> meters
       ]);
   }

}

rotation slerp( rotation a, rotation b, float f ) {

   float angleBetween = llAngleBetween(a, b);
   if ( angleBetween > PI )
       angleBetween = angleBetween - TWO_PI;
   return a*llAxisAngle2Rot(llRot2Axis(b/a)*a, angleBetween*f);

}//Written by Francis Chung, Taken from http://forums-archive.secondlife.com/54/3b/50692/1.html</lsl>

Camera Default - Sets the camera parameters back to their defaults: <lsl>camDefault() {

   llSetCameraParams([
       CAMERA_ACTIVE, FALSE, //1 is active, 0 is inactive
       CAMERA_BEHINDNESS_ANGLE, 10.0, //(0 to 180) degrees
       CAMERA_BEHINDNESS_LAG, 0.0, //(0 to 3) seconds
       CAMERA_DISTANCE, 3.0, //(0.5 to 10) meters
       CAMERA_FOCUS_LAG, 0.1 , //(0 to 3) seconds
       CAMERA_FOCUS_LOCKED, FALSE, //(TRUE or FALSE)
       CAMERA_FOCUS_THRESHOLD, 1.0, //(0 to 4) meters
       CAMERA_PITCH, 0.0, //(-45 to 80) degrees
       CAMERA_POSITION_LAG, 0.1, //(0 to 3) seconds
       CAMERA_POSITION_LOCKED, FALSE, //(TRUE or FALSE)
       CAMERA_POSITION_THRESHOLD, 1.0, //(0 to 4) meters
       CAMERA_FOCUS_OFFSET, ZERO_VECTOR //<-10,-10,-10> to <10,10,10> meters
   ]);

}</lsl>

Camera Match - Sets a prim's position and rotation to that of the user's camera (the one we have permissions for): <lsl>warpPos(vector destpos) {

   integer jumps = (integer)(llVecDist(destpos, llGetPos()) / 10.0) + 1;
   list rules = [PRIM_POSITION, destpos];
   integer count = 1;
   while (( count = count << 1 ) < jumps)
   {
       rules = (rules=[]) + rules + rules;
   }
   llSetPrimitiveParams(rules + llList2List(rules, (count - jumps) << 1, count));

} camMatch() {

   warpPos(llGetCameraPos());
   llSetRot(llGetCameraRot());

}</lsl> Note: Camera Match utilizes WarpPos to enable the camera tracking prim to jump great distances in an efficient manner.