How to make an object smoothly transition to a new location?

Processing Coding Questions
3

i made a NoGame using PVector
try it and see how the movement looks
( for me it look very natural, i trained air- / gun / pistol when i was young )

// https://discourse.processing.org/t/bug-with-arraylist/5949
// 11/2018 kll  / my first game ever, good its not really a game
// make a arraylist of pvector points
// calc shortest distance to the next target, aim, fire + remove the point from array

int idt, pmax = 10;
ArrayList<PVector> points = new ArrayList<PVector>();     // list of points
PVector target = new PVector(0, 0);                       // position of cross line
boolean theend = false, shoot = false;

int k = 0, kmax = 30;  //firing circles
float tdist, newdist, speedf = 0.04;   // speed factor multiplied with distance gives realistic targeting movement

void setup() {
 size( 300, 300);
 for (int i = 0; i < pmax; i++) points.add(new PVector(random(-width/2, width/2), random(-height/2, height/2)));
 //for ( PVector p : points ) println(p);
 println("targets: "+points.size());
}

void draw_lines() {
 stroke(200, 0, 0);
 line(target.x, -height/2, target.x, height/2); 
 line(-width/2, target.y, width/2, target.y);
}

void draw_points() {
 for (int i = 0; i < points.size(); i++) { 
   if ( i == idt ) stroke(200, 0, 0);  
   else noStroke();
   fill(0, 200, 0);
   ellipse(points.get(i).x, points.get(i).y, 8, 8);
 }
}

int get_nearest() {
 int idx = -1;                               // init to not found
 tdist = width;                              // init to max
 for (int i = 0; i < points.size(); i++) {
   newdist = dist(points.get(i).x, points.get(i).y, target.x, target.y);
   if ( newdist < tdist ) { 
     tdist = newdist; 
     idx = i;
   }
 }
 return idx;                                 // give index of nearest target
}

void aim() {
 if ( idt > -1 ) {
   PVector waytotarget = points.get(idt).copy();
   waytotarget.sub(target);
   if ( waytotarget.mag() > 0.5 ) {                     // thats close enough
     waytotarget.setMag(waytotarget.mag()*speedf);      // calc faster to short step in that direction
     target = target.add(waytotarget);                  // change target
   } else { 
     if ( !shoot ) println("shoot at "+idt);            // only print 
     shoot = true;
     points.remove(idt);
   }
 } else { 
   println("i win, but now i am alone!"); 
   theend = true;
 }
}

void fire() {                                   // only if shoot = true
 fill(200, 100, 0);
 stroke(255, 0, 0); 
 strokeWeight(3);
 ellipse(target.x, target.y, 2*k, 2*k);        // growing red circle
 strokeWeight(1);
 k++;
 if ( k >= kmax ) {  
   shoot = false; 
   k = 0;
 }
}

void show_end() {
 fill(0, 200, 0);
 rect(-50, -25, 100, 40);
 fill(200, 0, 0);
 text(" I WIN ! ", -20, 0);                    // well, what a wonder if you play alone and targets not move
}

void draw() {
 background(200, 200, 0);
 translate(width/2, height/2);
 if ( !theend ) {
   draw_lines();                               // cross lines
   draw_points();                              // all points fix pos, same size / red stroke for next target
   idt = get_nearest();                        // next ( nearest ) target
   if ( !shoot )      aim();                   // not walk while firing
   else               fire();                  // some show / red circles
 } else show_end();                            // all over, no play again button
}

and a other example for “easing”

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