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1. To move your object towards a location,provided targeted location and current location, you can suppose your current location origin and then get the relative position of the target location in polar coordinate.
2. This will give you the direction you need to travel.
3. Given the speed you want the object to travel,

4. Stepped example : (Click mouse to step, Hold down to see the hint, More content under demo 1, please scroll down to view Keynote 0)

   Processing
   Height 600 Width 600
   final int appwidth = 600; final int appheight = 600; final float stepsize = 10; targetedobject myobject; class targetedobject { // This is the object to move int mcurrentx, mcurrenty; // This will store the current location of the object int mtargetx, mtargety; // This will store the target location of the object int mtargetx_t, mtargety_t; // Step travel float mrotation; // This is the current orientation of this object float thisstep; boolean demostep; targetedobject( int x, int y, int r ) { // Initialize with coordinate and orientation mcurrentx = x; mtargetx = x; mcurrenty = y; mtargety = y; mrotation = r; demostep = false; } void updatedraw() { //Draws the shape pushMatrix(); translate( mcurrentx, mcurrenty ); rotate( mrotation ); noStroke(); fill( 255, 0, 0 ); ellipse(0, 0, 40, 40); noFill(); stroke(255); strokeWeight(5); line( -10, 0, 10, 0 ); line( 10, 0, 5, -5 ); line( 10, 0, 5, 5 ); popMatrix(); this.drawhelper()//******************************************************* // Global variables //******************************************************* final int appwidth = 600; final int appheight = 600; final float stepsize = 10; targetedobject myobject; //******************************************************* // The class of the moving object //******************************************************* class targetedobject { // This is the object to move int mcurrentx, mcurrenty; // This will store the current location of the object int mtargetx, mtargety; // This will store the target location of the object int mtargetx_t, mtargety_t; // Step travel float mrotation; // This is the current orientation of this object float thisstep; boolean demostep; // The flag whether the helper needs to be displayed or not targetedobject( int x, int y, int r ) { // Initialize with coordinate and orientation mcurrentx = x; mtargetx = x; mcurrenty = y; mtargety = y; mrotation = r; demostep = false; } void drawhelperupdatedraw() { // Draws if ( this.demostep ) { //Need drawthe shape pushMatrix(); translate( mcurrentx, float textx, textymcurrenty ); rotate( mrotation noFill(); strokeWeightnoStroke(3); stroke( 0,fill( 255, 2550, 1920 ); line( this.mcurrentx, this.mcurrenty, this.mtargetx, this.mtargety ellipse(0, 0, 40, 40); line( this.mtargetx, this.mcurrenty, this.mtargetx, this.mtargety noFill(); stroke(255); line( this.mcurrentx, this.mcurrenty, this.mtargetx, this.mcurrentystrokeWeight(5); line( -10, 0, 10, 0 ); line( 10, 0, 5, -5 textSize(24); line( 10, 0, textAlign(CENTER5, 5 BOTTOM); noStrokepopMatrix(); fill(255this.drawhelper(); } void drawhelper() { textx =if ( this.mtargetxdemostep ) +{ this.mcurrentx) // 2; Need draw helper textyfloat = this.mcurrentytextx, texty; textnoFill(); "X2 - X1", textx, texty strokeWeight(3); textAlign(LEFT, CENTERstroke( 0, 255, 255, 192 ); textx =line( this.mcurrentx, this.mcurrenty, this.mtargetx, this.mtargety ); texty = (this.mtargety +line( this.mtargetx, this.mcurrenty, this.mtargetx, this.mcurrenty) / 2mtargety ); textline( "Y2 - Y1", textx, texty this.mcurrentx, this.mcurrenty, this.mtargetx, this.mcurrenty ); textSize(24); textAlign(CENTER, CENTER BOTTOM); noStroke(); fill(255); textx = (this.mtargetx + this.mcurrentx) / 2; texty = (this.mtargety + this.mcurrenty) / 2; text( "LX2 - X1", textx, texty ); textAlign(LEFT, CENTER); textx noFill()= this.mtargetx; texty = strokeWeight(3)(this.mtargety + this.mcurrenty) / 2; stroke(255,0,0text( "Y2 - Y1", textx, texty ); arc( this.mcurrentx, this.mcurrenty, 64, 64, 0, this.mrotation textAlign(CENTER, CENTER); textx = (this.mtargetx + this.mcurrentx) +/ 402; texty = (this.mtargety + this.mcurrenty) +/ 402; text( degrees(this.mrotation)"L", textx, texty ); } } void startstep(int x, int y) { noFill(); float targetlengthstrokeWeight(3); float temprotation stroke(255,0,0); arc( this.demostep = true; mcurrentx, this.mcurrenty, 64, 64, 0, this.mtargetxmrotation = x); this.mtargetytextx = ythis.mcurrentx + 40; targetlength = sqrt(texty pow(= this.mtargetx - this.mcurrentx, 2 )mcurrenty + 40; powtext( degrees(this.mtargety - this.mcurrenty, 2 )mrotation), textx, texty ); //Get the target distance} } ifvoid startstep(targetlength <= 0.5int x, int y) { float targetlength; this.mrotation =float 0temprotation; this.demostep = return; true;   //Do Remember nottarget movecoordinates } this.mtargetx = x; if (targetlength > stepsize) { //Calculate step size this.thisstep = stepsize;this.mtargety = y;   // Calculate the distance between the endpoint and start point } targetlength = sqrt( pow( else { this.mtargetx - this.thisstepmcurrentx, =2 targetlength; }) + temprotation = acos( (this.mtargetx pow( this.mtargety - this.mcurrentx) / targetlength );mcurrenty, 2 ) ); //Get the target distance if (targetlength this.mtargety > this.mcurrenty <= 0.5) { //> 180 degrees this.mrotation = temprotation0; }else{ return; //Do not this.mrotationmove = 2 * PI} - temprotation; if (targetlength } > stepsize) { // Calculate the step targetsize this.mtargetx_t = (int)(this.thisstep * cos(this.mrotation))= stepsize; this.mtargety_t = (int)(this.thisstep * sin(this.mrotation)); } void endstep() {} else { this.thisstep = targetlength; }   // Get the direction (0~180 degree(s)) this.demosteptemprotation = false; acos( (this.mtargetx - this.mcurrentx) += this.mtargetx_t; / targetlength ); if ( this.mtargety > this.mcurrenty += this.mtargety_t; } } void setup() { size(appwidth, appheight); background(0); myobject = new targetedobject( width / 2, height / 2, 0 ); } void draw() { background(0); myobject.updatedraw(); } void mousePressed() { if (mouseButton == LEFT) { myobject.startstep(mouseX, mouseY); } } ) { this.mrotation = temprotation; }else{ this.mrotation = 2 * PI - temprotation; // > 180 degrees } // Calculate the step target this.mtargetx_t = (int)(this.thisstep * cos(this.mrotation)); this.mtargety_t = (int)(this.thisstep * sin(this.mrotation)); } void endstep() { this.demostep = false; // Move the object this.mcurrentx += this.mtargetx_t; this.mcurrenty += this.mtargety_t; } } //******************************************************* // Setup the size and the moving object //******************************************************* void setup() { size(appwidth, appheight); background(0); myobject = new targetedobject( width / 2, height / 2, 0 ); } //******************************************************* // Update the draw //******************************************************* void draw() { background(0); myobject.updatedraw(); } //******************************************************* // When mouse is pressed, start the stepping // Calculation process //******************************************************* void mousePressed() { if (mouseButton == LEFT) { myobject.startstep(mouseX, mouseY); } } //******************************************************* // After the mouse is released, // End the stepping and move the object //******************************************************* void mouseReleased() { if ( myobject.demostep ) { myobject.endstep(); } }

5. Anchor
   keynote00 keynote00

   Processingcode
   title Key note
   //Get the target distance targetlength = sqrt( pow( this.mtargetx - this.mcurrentx, 2 ) + pow( this.mtargety - this.mcurrenty, 2 ) ); //Arc cosin adjacent side divide by Hypotenuse //OR arc sin subtense divide by Hypotenuse //Not using tangent to avoid Divide by Zero temprotation = acos( (this.mtargetx - this.mcurrentx) / targetlength ); //In this case, we are using cosin, so for the angle > 180 which means that //targety is under currend y if ( this.mtargety > this.mcurrenty ) { //> 180 degrees this.mrotation = temprotation; }else{ this.mrotation = 2 * PI - temprotation; } //Now that we have the rotation, we recalculate the x and y we need to travel this.mtargetx_t = (int)(this.thisstep * cos(this.mrotation)); this.mtargety_t = (int)(this.thisstep * sin(this.mrotation)); //Finally, move the object this.mcurrentx += this.mtargetx_t; this.mcurrenty += this.mtargety_t;

6. Continuous Example

   Processing

   final int appwidth = 600; final int appheight = 600; final float stepsize = 5; targetedobject myobject; class targetedobject { // This is the object to move int mcurrentx, mcurrenty; // This will store the current location of the object int mtargetx, mtargety; // This will store the target location of the object int mtargetx_t, mtargety_t; // Step travel float mrotation; // This is the current orientation of this object float thisstep; boolean demostep; targetedobject( int x, int y, int r ) { // Initialize with coordinate and orientation mcurrentx = x; mtargetx = x; mcurrenty = y; mtargety = y; mrotation = r; demostep = false; } void updatedraw() { //Draws the shape pushMatrix(); translate( mcurrentx, mcurrenty ); rotate( mrotation ); noStroke(); fill( 255, 0, 0 ); ellipse(0, 0, 40, 40); noFill(); stroke(255); strokeWeight(5); line( -10, 0, 10, 0 ); line( 10, 0, 5, -5 ); line( 10, 0, 5, 5 ); popMatrix(); } void moveto(int x, int y) { this.mtargetx = x; this.mtargety = y; //Get the target distance float targetlength = sqrt( pow( this.mtargetx - this.mcurrentx, 2 ) + pow( this.mtargety - this.mcurrenty, 2 ) ); if(targetlength < 0.5){ return; } //Arc cosin adjacent side divide by Hypotenuse //OR arc sin subtense divide by Hypotenuse //Not using tangent to avoid Divide by Zero float temprotation = acos( (this.mtargetx - this.mcurrentx) / targetlength ); //In this case, we are using cosin, so for the angle > 180 which means that //targety is under currend y if ( this.mtargety > this.mcurrenty ) { //> 180 degrees this.mrotation = temprotation; } else { this.mrotation = 2 * PI - temprotation; } if (targetlength > stepsize) { //Calculate step size this.thisstep = stepsize; } else { this.thisstep = targetlength; } //Now that we have the rotation, we recalculate the x and y we need to travel this.mtargetx_t = (int)(this.thisstep * cos(this.mrotation)); this.mtargety_t = (int)(this.thisstep * sin(this.mrotation)); //Finally, move the object this.mcurrentx += this.mtargetx_t; this.mcurrenty += this.mtargety_t; } } void setup() { size(appwidth, appheight); background(0); myobject = new targetedobject( width / 2, height / 2, 0 ); frameRate(30); } void draw() { background(0); myobject.moveto( mouseX, mouseY ); myobject.updatedraw(); }

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