kasperpeulen / euclidthegame

A geometry game based on Euclid's Elements.

Euclid The Game

The goal of this project is to gamify geometric challanges. We use the geogebra software for this. This game is MIT licensed, see the LICENSE file.

See the facebook group for updates about the iOS game: https://www.facebook.com/euclidthegame

Message July 2014

A year ago I posted the idea for this game at stackexchange: http://math.stackexchange.com/questions/373672/about-euclids-elements-and-modern-video-games

I hoped that I could inspire game developers to make such a game. Well, I failed ! But I did inspire myself to learn a little bit about html/javascript and geogebra, and in this way, I was able to make this game.

If you have worked with geogebra, it may be not so hard to contribute to new levels. I've written a couple of function that make it easy to test if objects/lines/circles are drawn:

function ggbOnInit() {
  ggbApplet.debug("ggbOnInit");
  ggbApplet.registerAddListener("newObjectListener");
}

function newObjectListener(obj) {
  // this functions can check all general objects
  function checkobject(target, step) {
    if (obj != "finished") {
      var cmd = "finished = (" + obj + "== " + target + ")";
      ggbApplet.debug(cmd);
      ggbApplet.evalCommand(cmd);
      finished = ggbApplet.getValueString("finished");
      if (finished.indexOf("true") > -1) {
        ggbApplet.setVisible(step, true);
      }
    }
  }
  // this functions check line segments
  function checksegment(target, step) {
    if (ggbApplet.getObjectType(obj) == "segment") {
      //gives beginpoint and enpoint of object
      var objectcmd = ggbApplet.getCommandString(obj);
	  var openbracket = objectcmd.indexOf('[') + 1;
	  var comma = objectcmd.indexOf(',');
	  var closebracket = objectcmd.indexOf(']');
	  var beginpointobject = objectcmd.substring(openbracket, comma);
	  var endpointobject = objectcmd.substring(comma + 1, closebracket);
      //gives beginpoint and endpoint of target
      var targetcmd = ggbApplet.getCommandString(target); 
	  var openbracket = targetcmd.indexOf('[') + 1;
	  var comma = targetcmd.indexOf(',');
	  var closebracket = targetcmd.indexOf(']');
	  var beginpointtarget = targetcmd.substring(openbracket, comma);
	  var endpointtarget = targetcmd.substring(comma + 1, closebracket);
      //here it checks if endpoints of line segment are equal
      if (obj != "finished") {
        var cmd = "finished =((("+beginpointobject+"=="+beginpointtarget+")||("+beginpointobject+"=="+endpointtarget+"))&&(("+endpointobject+"=="+beginpointtarget+")||("+endpointobject+"=="+endpointtarget+")))";
        ggbApplet.debug(cmd);
        ggbApplet.evalCommand(cmd);
        finished = ggbApplet.getValueString("finished");
        if (finished.indexOf("true") > -1) {
          ggbApplet.setVisible(step, true);
        }
      }
    }
  }
   // this functions can check if line segment has right direction
  function checksegmentdirection(target, step) {
    if (ggbApplet.getObjectType(obj) == "segment" || ggbApplet.getObjectType(obj) == "line") {
    if (obj != "finished") {
      var cmd = "finished = (("+obj+"(1)=="+target+"(1))&&("+obj+"(-1)=="+target+"(-1)))";
      ggbApplet.debug(cmd);
      ggbApplet.evalCommand(cmd);
      finished = ggbApplet.getValueString("finished");
      if (finished.indexOf("true") > -1) {
        ggbApplet.setVisible(step, true);
      }
    }
  }
  }
  // this functions check if the new point is on the targetline
  function checkpointontarget(target, step) {
    if (ggbApplet.getObjectType(obj) == "point") {
    if (obj != "finished") {
      var cmd = "finished = ("+target+"(x("+obj+"))==y("+obj+"))";
      ggbApplet.debug(cmd);
      ggbApplet.evalCommand(cmd);
      finished = ggbApplet.getValueString("finished");
      if (finished.indexOf("true") > -1) {
        ggbApplet.setVisible(step, true);
      }
    }
  }
  }
  //here you can check all objects 


  //which step are neccesary to complete level
  if (ggbApplet.getVisible("step1") ) {
    ggbApplet.setVisible("complete", true);
	document.getElementById("level").style.visibility="visible";
  }
}