[please] help with vectors!

Programming Questions

smvalenga

in Programming Questions • 1 year ago

guys, i have this sketch as a simpler test to my work in progress, this is what i need:

-agents that move in a certain direction from the center

- vectors between the final positions of each agent, drawing the polygon that they form (i can not simply make lines, because later i will have to work with the vectors)

just for testing my vectors i did lines using the coordinates of them and they are completely crazy, instead of really drawing the shape of the polygon in red...

can somebody please,please help me??

int number = int(random(4, 10));
Agent [] agenten = new Agent[number];
void setup() {
size(500, 500);
smooth();
noFill();
float ang = TWO_PI / number;
//CREATES AGENTS
for (int i=0; i<agenten.length; i++) {
float dx = random(cos(ang*i), cos(ang*i+1));
float dy = random(sin (ang*i), sin (ang*i+1));
agenten[i] = new Agent(width/2, height/2, dx, dy);
}
}
void draw() {
background(255);
stroke(0);
noFill();
int time= millis();
int timelimit= 600;
PVector [] vec = new PVector [number] ;
for (int i=0; i<agenten.length; i++) {
agenten[i].render();
if (time < timelimit) {
agenten[i].move();
}
}
//CREATES VECTORS
for (int i=0; i < vec.length-1; i++) {
vec [i] = new PVector (agenten[i+1].position.x-agenten[i].position.x, agenten[i+1].position.y-agenten[i].position.y);
}
vec[vec.length-1] = new PVector (agenten[vec.length-1].position.x - agenten[0].position.x, agenten[vec.length-1].position.y - agenten[0].position.y);
println(vec);
beginShape();
noStroke();
fill(255,0,0,50);
for (int i = 0; i < agenten.length; i++) {
vertex(agenten[i].position.x,agenten[i].position.y);
}
endShape(CLOSE);
// CREATES LINES FROM ONE TO THE OTHER VECTOR
stroke(0);
translate (width/2, height/2);
for (int i=0; i<vec.length-1; i++) {
line (vec[i+1].x, vec[i+1].y, vec[i].x,vec[i].y);
}
line (vec[vec.length-1].x, vec[vec.length-1].y, vec[0].x,vec[0].y);
}
//AGENT
class Agent {
PVector position;
PVector direction;
int lim = 400;
Agent (float theX, float theY,float dx,float dy) {
position = new PVector (theX, theY);
direction = new PVector (dx, dy);
}
void render() {
for (int i=0; i<number;i++){
fill(255,0,0);
ellipse(position.x, position.y,1,1);
}
}
void move() {
direction.normalize();
direction.mult(random(20));
position.add(direction);
}
}

Replies(7)

Chrisir

Re: [please] help with vectors!

1 year ago

hello,

what do you want tot do with this?

vec [i] = new PVector (
agenten[i+1].position.x-agenten[i].position.x,
agenten[i+1].position.y-agenten[i].position.y);

It gives you a weird value that puts the x of the vec equal to the Xpos of the second agent MINUS the xPos of the first Agent. That is weird, because it gives you a point that's not your first nor the second agent. It's just somewhere down to the left.
Same goes for yPos.

Maybe you want the center of the two agents, then it would be (x1+x2) / 2 or so.

What do you want to be the difference between vec [i] and agenten[i] ?
Maybe agenten[i] is already your vector and you're thinking to complicate?

Cheers, Chrisir

Chrisir

Re: [please] help with vectors!

1 year ago

Maybe have a look at this:

int number = int(random(4, 10));
Agent [] agenten = new Agent[number];
PVector [] vec = new PVector [number] ;

final int timelimit = 3600;

void setup() {
  size(1000, 800);
  smooth();
  noFill();

  float ang = TWO_PI / number;

  //CREATES AGENTS
  for (int i=0; i
              
               length; i++) {
    
               float dx = 
               random(
               cos(ang*i), 
               cos(ang*i+1));
    
               float dy = 
               random(
               sin (ang*i), 
               sin (ang*i+1));
    agenten[i] = 
               new Agent(
               width/2, 
               height/2, dx, dy);
  }
  
               frameRate(9) ;
} 
               // func


               void 
               draw() {
  
               background(255);
  
               stroke(0);
  
               noFill();

  
               for (
               int i=0; i
               
                length; i++) {     agenten[i].render();     
                if (
                millis() < timelimit) {       agenten[i].
                move();     }   } 
                // for   
                //CREATES VECTORS   
                for (
                int i=0; i < vec.
                length-1; i++) {     
                /* 
                    vec [i] = new PVector ( 
                     agenten[i+1].position.x-agenten[i].position.x,  
                     agenten[i+1].position.y-agenten[i].position.y); 
                     */     vec [i] = 
                new 
                PVector (     (agenten[i+1].position.x+agenten[i].position.x) / 2,      (agenten[i+1].position.y+agenten[i].position.y) / 2);   }   
                // close it    
                /* 
                  vec[vec.length-1] = new PVector ( 
                   agenten[vec.length-1].position.x - agenten[0].position.x,  
                   agenten[vec.length-1].position.y - agenten[0].position.y); 
                   */   vec [vec.
                length-1] = 
                new 
                PVector (   (agenten[vec.
                length-1].position.x+agenten[0].position.x) / 2,   (agenten[vec.
                length-1].position.y+agenten[0].position.y) / 2);   
                println(vec);   
                // shape from agents positions    
                beginShape();   
                noStroke();   
                fill(255, 0, 0, 50);   
                for (
                int i = 0; i < agenten.
                length; i++) {     
                vertex(agenten[i].position.x, agenten[i].position.y);   }   
                endShape(
                CLOSE);   
                // CREATES LINES FROM ONE TO THE OTHER VECTOR   
                stroke(0);   
                // translate (width/2, height/2);   
                for (
                int i=0; i
                
                 length-1; i++) {     
                 line (vec[i+1].x, vec[i+1].y, vec[i].x, vec[i].y);   }   
                 // close it    
                 line (vec[vec.
                 length-1].x, vec[vec.
                 length-1].y, vec[0].x, vec[0].y); } 
                 // func  
                 // ==================================================================== 
                 //AGENT 
                 class Agent {   
                 PVector position;   
                 PVector direction;   
                 int lim = 400;   Agent (
                 float theX, 
                 float theY, 
                 float dx, 
                 float dy) {     position    = 
                 new 
                 PVector (theX, theY);     direction   = 
                 new 
                 PVector (dx, dy);   } 
                 // constructor   
                 void render() {     
                 for (
                 int i=0; i
                 
                  fill(255, 0, 0);       
                  ellipse(position.x, position.y, 1, 1);     } 
                  // for   } 
                  // func    
                  void 
                  move() {     direction.
                  normalize();     direction.
                  mult(
                  random(20));     position.
                  add(direction);   } 
                  // func } 
                  // class

smvalenga

Re: Re: [please] help with vectors!

1 year ago

hey! thaks! it helped me a lot to understand better how they work!

ps- i had posted another question here, but forget about it.. I DID IT! I DID IT!!!

Chrisir

Re: [please] help with vectors!

1 year ago

oups, I just finished the program before I saw your message that you made it...


int number = int(random(4, 10));
Agent [] agenten = new Agent[number];


void setup() {
  size(500, 500);
  smooth();
  noFill();

  float ang = TWO_PI / number;

  //CREATES AGENTS
  for (int i=0; i
              
               length; i++) {
    
               float dx = 
               random(
               cos(ang*i), 
               cos(ang*i+1));
    
               float dy = 
               random(
               sin (ang*i), 
               sin (ang*i+1));
    agenten[i] = 
               new Agent(
               width/2, 
               height/2, dx, dy);
  }
  
               // frameRate(11);
}


               void 
               draw() {
  
               background(255);
  
               stroke(0);
  
               noFill();

  
               int time= 
               millis();
  
               int timelimit= 500;

  
               PVector [] vec = 
               new 
               PVector [number] ;

  
               for (
               int i=0; i
               
                length; i++) {     agenten[i].render();     
                if (time < timelimit) {       agenten[i].
                move();     }   }   
                stroke(255, 0, 0);   
                ellipse (agenten[0].position.x, agenten[0].position.y, 10, 10);   
                //CREATES VECTORS   
                for (
                int i=0; i < vec.
                length-1; i++) {     vec [i] = 
                new 
                PVector (agenten[i+1].position.x-agenten[i].position.x, agenten[i+1].position.y-agenten[i].position.y);   }   
                //close it   vec[vec.
                length-1] = 
                new 
                PVector (agenten[0].position.x - agenten[vec.
                length-1].position.x, agenten[0].position.y - agenten[vec.
                length-1].position.y);   
                // CREATES LINES FROM ONE TO THE OTHER VECTOR   
                stroke(0);   
                for (
                int i=0; i
                
                 length-1; i++) {     
                 line (agenten[i].position.x, agenten[i].position.y, agenten[i].position.x + vec[i].x, agenten[i].position.y + vec[i].y);   }   
                 //close it   
                 line (   agenten[vec.
                 length-1].position.x,   agenten[vec.
                 length-1].position.y,   agenten[vec.
                 length-1].position.x + vec[vec.
                 length-1].x,   agenten[vec.
                 length-1].position.y + vec[vec.
                 length-1].y);   
                 //CREATES VECTORS IN THE MIDDLE    
                 PVector [] mid = 
                 new 
                 PVector [vec.
                 length] ;   
                 for (
                 int i=0; i< vec.
                 length-1;i++) {     mid[i]= 
                 new 
                 PVector ((agenten[i].position.x+agenten[i+1].position.x)/2, (agenten[i].position.y+agenten[i+1].position.y)/2);   }   mid[mid.
                 length-1]= 
                 new 
                 PVector ((agenten[mid.
                 length-1].position.x+agenten[0].position.x)/2, (agenten[mid.
                 length-1].position.y+agenten[0].position.y)/2);   
                 //ANGLE BETWEEN   
                 float [] ang = 
                 new 
                 float [vec.
                 length];   
                 for (
                 int i=0; i
                 
                  length-1; i++) {     
                  for (
                  int j=0; j
                  
                   length-1; j++) {       
                   // test not against itself       
                   if (i!=j) {         ang[i] = 
                   PVector.
                   angleBetween(vec[j], vec[i]);         
                   if ( ang[i] > 
                   radians(160) && ang[i] < 
                   radians (180)) {           
                   line (mid[j].x, mid[j].y, mid[i].x, mid[i].y);         } 
                   // if       } 
                   // if     } 
                   // for j   } 
                   // for i   
                   /* 
                     float [] ang = new float [vec.length]; 
                      for (int i=0; i
                     
                        ang[i] = PVector.angleBetween(vec[0], vec[i]); 
                        if ( ang[i] > radians(160) && ang[i] < radians (180)) { 
                        line (mid[0].x, mid[0].y, mid[i].x, mid[i].y); 
                        } 
                        } 
                         
                        float [] ang1 = new float [vec.length]; 
                        for (int i=0; i
                       
                          ang1[i] = PVector.angleBetween(vec[1], vec[i]); 
                          if ( ang1[i] > radians(160) && ang1[i] < radians (180)) { 
                          line (mid[1].x, mid[1].y, mid[i].x, mid[i].y); 
                          } 
                          } 
                          */ } 
                       // func 
                       //======================================================= 
                       //AGENT 
                       class Agent {   
                       PVector position;   
                       PVector direction;   
                       int lim = 400;   Agent (
                       float theX, 
                       float theY, 
                       float dx, 
                       float dy) {     position    = 
                       new 
                       PVector (theX, theY);     direction   = 
                       new 
                       PVector (dx, dy);   }   
                       void render() {     
                       for (
                       int i=0; i
                       
                        //fill(255,0,0);
                       
                             
                     ellipse(position.x, position.y, 3, 3);     }   }   
                     void 
                     move() {     direction.
                     normalize();     direction.
                     mult(
                     random(20));     position.
                     add(direction);   } }

smvalenga

Re: Re: [please] help with vectors!

1 year ago

i know, its too much of your patience and of course i understand if you cant make it =)

the last thing that i need to accomplish in order to put all my program together, is this:

-if the angles between the vectors of the polygon are almos parallel, i have to make lines connecting them, but only IF the length of the line is less than a value. that means instead of simply lines (what i have done so far) i need the PVectors, so i can access their magnitude... AND AGAIN... problems with the vectors and lines using them =(

would you please check whats going on? its gonna be the last question.. its just cause i need that by monday.

thaks a LOT, cheers!

int number = int(random(4, 10));
Agent [] agenten = new Agent[number];
void setup() {
size(500, 500);
smooth();
noFill();
float ang = TWO_PI / number;
//CREATES AGENTS
for (int i=0; i<agenten.length; i++) {
float dx = random(cos(ang*i), cos(ang*i+1));
float dy = random(sin (ang*i), sin (ang*i+1));
agenten[i] = new Agent(width/2, height/2, dx, dy);
}
}
void draw() {
background(255);
stroke(0);
noFill();
int time= millis();
int timelimit= 600;
PVector [] vec = new PVector [number] ;
for (int i=0; i<agenten.length; i++) {
agenten[i].render();
if (time < timelimit) {
agenten[i].move();
}
}
stroke(255,0,0);
ellipse (agenten[0].position.x, agenten[0].position.y, 10,10);
//CREATES VECTORS
for (int i=0; i < vec.length-1; i++) {
vec [i] = new PVector (agenten[i+1].position.x-agenten[i].position.x, agenten[i+1].position.y-agenten[i].position.y);
}
vec[vec.length-1] = new PVector (agenten[0].position.x - agenten[vec.length-1].position.x, agenten[0].position.y - agenten[vec.length-1].position.y);
beginShape();
noStroke();
fill(0,0,255,50);
for (int i = 0; i < agenten.length; i++) {
vertex(agenten[i].position.x,agenten[i].position.y);
}
endShape(CLOSE);
// CREATES LINES FROM ONE TO THE OTHER VECTOR
stroke(0);
//for (int i=0; i<vec.length-1; i++) {
//line (agenten[i].position.x, agenten[i].position.y, agenten[i].position.x + vec[i].x, agenten[i].position.y + vec[i].y);
// }
//line (agenten[0].position.x, agenten[0].position.y, agenten[0].position.x + vec[0].x, agenten[0].position.y + vec[0].y);
//line (agenten[vec.length-1].position.x, agenten[vec.length-1].position.y, agenten[vec.length-1].position.x + vec[vec.length-1].x, agenten[vec.length-1].position.y + vec[vec.length-1].y);
//CREATES VECTORS IN THE MIDDLE
PVector [] mid = new PVector [vec.length] ;
for (int i=0; i< vec.length-1;i++) {
mid[i]= new PVector ((agenten[i].position.x+agenten[i+1].position.x)/2, (agenten[i].position.y+agenten[i+1].position.y)/2);
}
mid[mid.length-1]= new PVector ((agenten[mid.length-1].position.x+agenten[0].position.x)/2, (agenten[mid.length-1].position.y+agenten[0].position.y)/2);
//ANGLE BETWEEN
for (int j=0;j<vec.length;j++) {
float [] ang = new float [vec.length];
for (int i=0; i<ang.length-1; i++) {
ang[i]= PVector.angleBetween(vec[j], vec[i]);
if ( ang[i] > radians(160) && ang[i] < radians (180)){
//line (mid[j].x,mid[j].y,mid[i].x,mid[i].y);
PVector a;
a = new PVector ((mid[j].x-mid[i].x),(mid[j].y-mid[i].y));
line (a.x,a.y,(a.x+mid[i].x),(a.y+mid[i].y));
println(a);
}
}
}
}
//========================================================
//AGENT
class Agent {
PVector position;
PVector direction;
int lim = 400;
Agent (float theX, float theY,float dx,float dy) {
position = new PVector (theX, theY);
direction = new PVector (dx, dy);
}
void render() {
for (int i=0; i<number;i++){
//fill(255,0,0);
ellipse(position.x, position.y,3,3);
}
}
void move() {
direction.normalize();
direction.mult(random(20));
position.add(direction);
}
}

Chrisir

Re: [please] help with vectors!

1 year ago

ok, look up dist in the reference:
http://www.processing.org/reference/PVector_dist_.html

It gives you the distance of two vectors.

Calculates the Euclidean distance between two points (considering a point as a vector object).

Assuming that you are talking about the length of the new connecting lines:

After

//line (mid[j].x,mid[j].y,mid[i].x,mid[i].y);

insert

PVector v1 = new PVector(mid[j].x,mid[j].y); // get vec from point1
PVector v2 = new PVector(mid[i].x,mid[i].y); // get vec from point2
float d = v1.dist(v2); // get distance
println(d); // Prints the distance
// check if distance is smaller
if (d < yoursecretthreshholdvalue) {
// if yes, connect
line (mid[j].x,mid[j].y,mid[i].x,mid[i].y);
}



I hope that helps. 

BTW: use CTRL-T all the time, it makes your Code nicer.  

I am away now for over a week. 


Cheers, Chrisir


P.S. 
delete the first commented line  //line (mid[j].x,mid[j].y,mid[i].x,mid[i].y);

smvalenga

Re: Re: [please] help with vectors!

1 year ago

THANKS THANKS THANKS! =)

incredible my capacity to complicate stuff!

Top Reply