Hello,

i'm trying to make a sketch with a matrix of 400 squares(20,20) and when the mouse rollover one square, it ligths up.
i started the skecth from Daniel Shiffman exmaple 9-10,
all "mouse rollover" part is working but i can't make the matrix and i can't see what's the problem ??
in general for making the matrix i'll do something like this:

 for (int i = 0; i < 20; i++ ) {
  for (int i2 = 0; i2 < 20; i2++) {  
   rect(i*10, i2*10, 10, 10);
 }
}


AND THIS IS MY SKETCH:




Square [] squares = new Square[20];

void setup() {
 size(200,200);
 
 // Initialize all Square objects
 for (int i = 0; i < squares.length; i++ ) {
  for (int i2 = 0; i2 < squares.length; i2++){  
   squares[i] = new Square(i*10, i2*10);
 }
}
}

void draw() {
 
 background(100);
 // Move and display all Square objects
 for (int i = 0; i < squares.length; i ++ ) {
   // Check if mouse is over the Square
   squares[i].rollover(mouseX,mouseY); // Passing the mouse coordinates into an object.
   //stripes[i].move();
   squares[i].display();
 }
}


class Square {
 
 float x;     // horizontal location of Square
 float y;  
 float w;     // width of stripe
 
 
 boolean mouse;

 Square(float x2, float y2) {
   // All stripes start at 0
   x = x2;
   y = y2;

   w = 10;
   mouse = false;
 }

 // Draw square
 void display() {
 
   // Boolean variable determines Square color.
   if (mouse) {
     fill(255);
   } else {
     fill(255,100);
   }
   
   noStroke();
   rect(x, y, w, w);
 }


// Check to see if point (mx,my) is inside the Square.
 void rollover(int mx, int my) {
   // Left edge is x, Right edge is x + w
   if (mx > x && mx < x + w) {
     mouse = true;
   } else {
     mouse = false;
   }
 }
}






Sorry my english, thanks for your help.

thanks philho!

i'm testing "y" now but everytime i'm trying to generate more than 20 squares, i can't see it.
if i generate 1, the line is in the top,
if i generate 5, the line is in the middle
and if i generate 20, the line is at the end.

why processing is only keeping the last line of code ?


here is my new code:


// An array of square
Square[] squares = new Square[10];

void setup() {
 size(200,200);
 
 // Initialize all square objects
 for (int i = 0; i < squares.length; i++ ) {
  for (int i2 = 0; i2 < squares.length; i2++){  
   squares[i] = new Square(i*10, i2*10);
 }
}
}

void draw() {
 
 background(100);
 // Move and display all square objects
 for (int i = 0; i < squares.length; i ++ ) {
   // Check if mouse is over the square
   squares[i].rollover(mouseX,mouseY); // Passing the mouse coordinates into an object.
   //square[i].move();
   squares[i].display();
 }
}



class Square {
 
 float x;  // horizontal location of square
 float y;  
 //float speed; // speed of square
 float w;     // width of square
 
 // A boolean variable keeps track of the object's state.
 boolean mouse; // state of square (mouse is over or not?)

 Square(float x2, float y2) {
   // All squares start at 0
   x = x2;
   y = y2;
   // All squares have a random positive speed
   //speed = random(1);
   w = 10;
   mouse = false;
 }

 // Draw stripe
 void display() {
   
   // Boolean variable determines square color.
   if (mouse) {
     fill(255);
   } else {
     fill(255,100);
   }
   
   noStroke();
   rectMode(CENTER);
   rect(x+w/2, y+w/2, w, w);
 }

/* // Move square
 void move() {
   x += speed;
   if (x > width + 20) x = -20;
 } */

// Check to see if point (mx,my) is inside the square.
 void rollover(int mx, int my) {
   // Left edge is x, Right edge is x + w
   if (mx > x && mx < x + w && my > y && my < y + w  ) {
     mouse = true;
   } else {
     mouse = false;
   }
   
 }
}

WOw!! thanks a lot!!!

I'm using this skecth only for learning porpuses, to work with classes, and i use squares beacuse is easy...

I have only more question...

when you use : (to initialize all square objects)

...
squares[r * ARRAY_SIZE + c] = new Square(r*10, c*10)
...


what i think is happening in the "draw" with two "for":

squares[0 * 20 + 0]  /// = 0

squares[0 * 20 + 1] /// =  1

squares[0 * 20 + 2] /// =  2

etc...


squares[1 * 20 + 0] /// = 20

squares[1 * 20 + 1] /// = 21

squares[1 * 20 + 2] /// = 22

etc...

that's rigth?



and thank you for the simplified routine of "mouse", is very usefull....
with your technic, now, i don't need to specify whether is true or false, with "if" condition.

tHANKS AGAIN!!!!!