hello,
i drew a map with different districts on different layers in an svg file. each district has its own unique color and is a different odd shape.

i am trying draw a dot into a district onto a map, which i have each defined a bounding box area...but before i draw that dot to the district on the map, i would like to check if that dot is sitting in the color of that area and not in a non-colored area within the bounding box.

am i not using the correct syntax?

this is part of my code below. thanks in advance!

/*note

the "grp" is the svg file of my map (grp = RG.loadShape("data/sf-map2hoods.svg");), where each district on the map is on its own layer with its own color.

>>> color neighborhoodColor = grp.get(xpos, ypos);

*/



//constructor
 DrawDot (int h, int c, String w, String s, String sx, String u){  
   hood = h; //assign areas to hood  

   
   //get a random coordinate for the dot....
   xpos = int(random(lowerBoundX[hood], upperBoundX[hood])); //width. reads the district number and gets the assigned coordinates and dimentions
   ypos = int(random(lowerBoundY[hood], upperBoundY[hood])); //height  
   
   
  //...while the dot is not in it's correct area, keep checking    
    while (IsInNeighborhood == false){ //while the dot is not in the correct place...
 IsInHood(xpos, ypos);   //send x&ypos to function to check to see if the x & y positions are in the correct area
   
    if(IsInNeighborhood == true){  //if the dot is in the correct place...
   //...assign the spot!
   xpos = random(lowerBoundX[hood], upperBoundX[hood]); //width. reads the district number and gets the assigned coordinates and dimentions
   ypos = random(lowerBoundY[hood], upperBoundY[hood]); //height  
}//end if true
   }//end while false
 
   //check to see if dot is in the coorect  
   int IsInHood(int xpos, int ypos){ //passing x & y to check if they are sitting in the hood    
color neighborhoodColor = sfmap.get(xpos, ypos);  //read a point hood color  
return(neighborhoodColor); //return the hood color  
//return(xpos, ypos); //return the hood color??  
IsInNeighborhood == true;
   }
 
    } //end constructor

haha. only if. thanks! i'm getting an error that says "The operator ! is undefined for the argument types(s) int"? I tried doing something like this : (!(IsInHood(xpos, ypos))); , but that doesn't seem to work either. for the return, do i just want to "return neighborhoodColor"? Not sure what to == it to?

   do{
   //get a random coordinate for the dot....
   xpos = int(random(lowerBoundX[hood], upperBoundX[hood]));
   ypos = int(random(lowerBoundY[hood], upperBoundY[hood]));
   } while (!IsInHood(xpos, ypos)); //while the dot is not in the correct place...
 }//end constructor
       
   //check to see if dot is in the coorect  
   int IsInHood(int xpos, int ypos){ //passing x & y to check if they are sitting in the hood  
     color neighborhoodColor = grp.get(xpos, ypos);  //read a point hood color
     return neighborhoodColor==hood; //NOT SURE WHAT DO DO HERE?
   }

thanks, no worries at all!

my hood is an array of neighborhoods. they are all read as ints, so each dot that i want to put on the map has its own assigned neighborhood. so say this dot belongs in neighborhood "1". does that make sense?


now i'm getting:
"The function get(int,int) does not exist." ?

   //check to see if dot is in the coorect  
   boolean IsInHood(int xpos, int ypos){ //passing x & y to check if they are sitting in the hood  
     color neighborhoodColor = grp.get(xpos, ypos);  //read a point hood color
     return neighborhoodColor;
   }

Mmm, let summarize.

IsInHood is a function returning a boolean, true or false. It must not return a color, it must compare color at given coordinates to expected color. Maybe you must also pass the expected color as parameter of the function.
You need probably another array, the expected color corresponding to the defined bounds.

I overlooked another fact: grp is a PShape. It doesn't has a get(int, int) method, indeed. You need to render the PShape on a PGraphics and get the pixel color value from this image.

rrrr wrote on Mar 18^th, 2009, 6:47pm:
What problem

   }while (!IsInHood(xpos, ypos));

make that

   }while (!IsInHood(xpos, ypos, hood));

and

   boolean IsInHood(int xpos, int ypos){
   color neighborhoodColor = sfmap.get(xpos, ypos);  
     if(neighborhoodColor == colorValue[hood]){    
     }
     return true;
   }

Uh hood isn't known there. Should be:

   boolean IsInHood(int xpos, int ypos, int hood){
     color neighborhoodColor = sfmap.get(xpos, ypos);  
     return neighborhoodColor == colorValue[hood];
   }

And if you are uneasy with boolean expressions, you can write:

 if (neighborhoodColor == colorValue[hood])
   return true;
 return false;

but I find this less elegant.

so i'm still using the geomerative library: (http://www.ricardmarxer.com/processing/geomerative/documentation/rpoint_class_rpoint.htm) and trying to do something like this get (http://processing.org/reference/get_.html)

i'm getting an error saying: "cannot convet from boolean to int" on the "color neighborhoodColor = grp.children[hood].contains(p);" line.

it's almost there, but not quite :(

do{ xpos = random(lowerBoundX[hood], upperBoundX[hood]);
   ypos = random(lowerBoundY[hood], upperBoundY[hood]);
 }while (!IsInHood(xpos, ypos, hood));
       
boolean IsInHood(float xpos, float ypos, int hood){  
 RPoint p = new RPoint(xpos, ypos);
 color neighborhoodColor = grp.children[hood].contains(p);
 return neighborhoodColor == colorValue[hood];
   }

thanks. i just don't know how i can write it like "color cp = get(30, 20);" but using the syntax of the geomerative library with my svg file, which i'm trying to read the color of each shape in a different bounding box. if the xpos and ypos matches a specific color within that bounding box, and not some other color in that box, then return true.

//Here is a rough set up of what I have now:

PImage sfmap;

void setup() {
 sfmap = loadImage("data/sf-map2hoods.png");
}

//below is a section of a class i have

do{ //get a random coordinate for the dot....
       xpos = int(random(lowerBoundX[hood], upperBoundX[hood]));
       ypos = int(random(lowerBoundY[hood], upperBoundY[hood]));
       println("LowerX/UpperX: " + lowerBoundX[hood] + ", " + upperBoundX[hood]);
       println("LowerY/UpperY: " + lowerBoundY[hood] + ", " + upperBoundY[hood]);
       println("RandomPlaceLocation: " + xpos + ", " + ypos);  
       println("test test test");
   }while (!IsInHood(xpos, ypos, hood)); //while the dot is not in the correct place...

  //is this necessary for after the points are found?
   //if (IsInHood(xpos, ypos, hood)){
   //  x = xpos;
   // y = ypos;
   //}

 }//end constructor
     
 boolean IsInHood(int xpos, int ypos, int hood){
    color neighborhoodColor = sfmap.get(xpos, ypos);
    println("i am returning");
    return neighborhoodColor == colorValue[hood];
  }

//i'm getting a "java.lang.NullPointerException" and it doesn't seem to be running through the boolean function cause it's not println("i am returning"). it's getting a random xpos and ypos in the do{}while, but i don't think it's checking to see if that point matches the color of that area? i thought i could use "sfmap.get" just like sfmap.pixel"?