dcsimg
A Flash Developer Resource Site

Results 1 to 3 of 3

Thread: X & Y coordinates from grid

  1. #1
    Official FK nice guy and MOD 3PRIMATES's Avatar
    Join Date
    Apr 2002
    Location
    Portland Oregon
    Posts
    1,645

    X & Y coordinates from grid

    Hello peeps, my first time here in Math and Physics.

    I am not a math junky by any means, and am having a hard time getting my head around a formula.

    Heres the deal:

    I have a a grid with 10,000 sqaures on an 800x800 canvas
    The grid in not of Mcs but an array.

    Getting the _x,_y coords from a mouse event is not a problem, but I need to get the _x,_y coords based upon a returned number from the database.

    PHP Code:
    var gridHeight 800;

    var 
    gridWidth 800;

    var 
    markerHeight 8;
    var 
    markerWidth 8;

    var 
    gridRows gridHeight markerHeight;
    var 
    gridCols gridWidth markerWidth;


    // 3046 of 10000 db items
    // known values for mcId 3046 are X:552 Y:432
    // using this value to test with, the math formula should return 432 
    // just as  mine below returns 552
    var mcId 3046;

    // this is my formula to determine the _x value of a grid square based upon the 
    // the mcId value between 1 and 10000
    mcX Math.round(Math.floor((gridCols-(mcId gridWidth)*markerWidth))*markerWidth); 
    That forumla works 100% in all cases so far for grabbing the x coordinate based upon the id number between 1 and 10,000.

    Now I need help with getting the _y value. I cant for the life of me figure this out.

    Any ideas you math wizards?

    Any help would be appreciated,

    3P
    Last edited by 3PRIMATES; 11-20-2007 at 02:34 AM.

  2. #2
    Official FK nice guy and MOD 3PRIMATES's Avatar
    Join Date
    Apr 2002
    Location
    Portland Oregon
    Posts
    1,645
    Ok, I got it. My brain is melting but I did it..LOL

    Here is the modified and working code. If you would, please look it over and see if I have done anything real idiotic. Think iy could be trimmed down a bit but I am not sure.

    thanks.

    3P

    PHP Code:
    gridHeight 800;
    gridWidth 800;

    markerHeight 8;
    markerWidth 8;

    gridRows gridHeight markerHeight;
    gridCols gridWidth markerWidth;
    gridSquared gridRows gridCols;

    // mcId for testing: 
    //3046 of 10000 db items
    mcId 3046;

    // formula to determine _x value of grid square based on value between 1 and 10000
    mcX Math.round(Math.floor(gridCols - (mcId gridCols)) * markerWidth);

    // formula to determine _y value of grid square based on value between 1 and 10000
    mcY Math.round(Math.floor((10000 mcId) * markerHeight)- mcX gridRows); 

  3. #3
    M.D. mr_malee's Avatar
    Join Date
    Dec 2002
    Location
    Shelter
    Posts
    4,140
    var mcX:int = (mcId % gridCols) * markerWidth;
    var mcY:int = (mcId / gridCols) * markerHeight;

    that should do it.
    lather yourself up with soap - soap arcade

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  




Click Here to Expand Forum to Full Width

HTML5 Development Center