scene.js

/*\
 * scene
 * 
 * scene in F.LF; keeps a list a characters and items
 | vol= //the volume format
 | {
 | 	x, y, z, //the reference point
 | 	vx, vy, w, h, //the volume defined with reference to (x,y,z)
 | 	zwidth	//zwidth spans into the +ve and -ve direction
 | }
\*/

define(['F.core/util','F.core/collision'], function (Futil,Fcollision)
{

function scene (config)
{
	this.live = {}; //list of living objects
	this.uid = 0;
}

scene.prototype.add = function(C)
{
	this.uid++;
	C.uid = this.uid;
	this.live[C.uid]=C;
	return C.uid;
}

scene.prototype.remove = function(C)
{
	var uid = C.uid;
	delete this.live[C.uid];
	C.uid=-1;
	return uid;
}

/*\
 * scene.query
 [ method ]
 - exclude (object) or (array of objects)
 - where (object) what to intersect with
 * examples, can mixin the following properties
 | {tag:'body'} intersect with body
 | {tag:'itr:2'} intersect with itr kind:2
 | {type:'character'} with character only
 | {not_team:1} exclude team
 | {filter:function}
 = (array) all the objects whose volume intersect with the specified volume
\*/
scene.prototype.query = function(volume, exclude, where)
{
	var result=[];
	var tag=where.tag;
	if(!tag) tag='body';
	var tagvalue=0;
	var tag_split=tag.split(':');
	tag = tag_split[0];
	tagvalue = tag_split[1];

	for ( var i in this.live)
	{
		var excluded=false;
		if( exclude instanceof Array)
		{
			for( var ex=0; ex<exclude.length; ex++)
			{
				if( this.live[i] === exclude[ex])
				{
					excluded=true;
					break;
				}
			}
		}
		else if( exclude)
		{
			if( this.live[i] === exclude)
				excluded=true;
		}
		if( excluded)
			continue;

		if( where.not_team && this.live[i].team === where.not_team)
			continue;

		if( where.type && this.live[i].type !== where.type)
			continue;

		if( where.filter && !where.filter(this.live[i]))
			continue;

		if( this.live[i]['vol_'+tag])
		{
			var vol = this.live[i]['vol_'+tag](tagvalue);
			for( var j=0; j<vol.length; j++)
			{
				if( this.intersect( volume, vol[j]))
				{
					result.push( this.live[i] );
					break;
				}
			}
		}
	}
	return result;
}

//return true if volume A and B intersect
scene.prototype.intersect = function(A,B)
{
	//less garbage version
	var A_left=A.x+A.vx, A_top=A.y+A.vy, A_right=A.x+A.vx+A.w, A_bottom=A.y+A.vy+A.h;
	var B_left=B.x+B.vx, B_top=B.y+B.vy, B_right=B.x+B.vx+B.w, B_bottom=B.y+B.vy+B.h;

	return ( Fcollision.rect_flat(
			A_left, A_top, A_right, A_bottom,
			B_left, B_top, B_right, B_bottom) &&
		Fcollision.rect_flat(
			A.z-A.zwidth, 0, A.z+A.zwidth, 1,
			B.z-B.zwidth, 0, B.z+B.zwidth, 1)
		);
}
scene.prototype.intersect_old = function(A,B)
{
	var AV={ left:A.x+A.vx, top:A.y+A.vy, right:A.x+A.vx+A.w, bottom:A.y+A.vy+A.h };
	var BV={ left:B.x+B.vx, top:B.y+B.vy, right:B.x+B.vx+B.w, bottom:B.y+B.vy+B.h };

	return ( Fcollision.rect( AV, BV ) && Fcollision.rect(
	{ left:A.z-A.zwidth, top:0, right:A.z+A.zwidth, bottom:1 },
	{ left:B.z-B.zwidth, top:0, right:B.z+B.zwidth, bottom:1 }
	));
}

//return the distance between object A and B, as measured at center points
scene.prototype.distance=function(A,B)
{
	var dx= (A.x+A.centerx) - (B.x+B.centerx);
	var dy= A.y - B.y;
	var dz= (A.z+A.centery) - (B.z+B.centery);

	return Math.sqrt(dx*dx+dy*dy+dz*dz);
}

return scene;
});