source: [view]
dojo.provide("dojox.gfx3d.scheduler");
dojo.provide("dojox.gfx3d.drawer");
dojo.require("dojox.gfx3d.vector");
dojo.mixin(dojox.gfx3d.scheduler, {
zOrder: function(buffer, order){
order = order ? order : dojox.gfx3d.scheduler.order;
buffer.sort(function(a, b){
return order(b) - order(a);
});
return buffer;
},
bsp: function(buffer, outline){
// console.debug("BSP scheduler");
outline = outline ? outline : dojox.gfx3d.scheduler.outline;
var p = new dojox.gfx3d.scheduler.BinarySearchTree(buffer[0], outline);
dojo.forEach(buffer.slice(1), function(item){ p.add(item, outline); });
return p.iterate(outline);
},
// default implementation
order: function(it){
return it.getZOrder();
},
outline: function(it){
return it.getOutline();
}
});
dojo.declare("dojox.gfx3d.scheduler.BinarySearchTree", null, {
constructor: function(obj, outline){
// summary: build the binary search tree, using binary space partition algorithm.
// The idea is for any polygon, for example, (a, b, c), the space is divided by
// the plane into two space: plus and minus.
//
// for any arbitary vertex p, if(p - a) dotProduct n = 0, p is inside the plane,
// > 0, p is in the plus space, vice versa for minus space.
// n is the normal vector that is perpendicular the plate, defined as:
// n = ( b - a) crossProduct ( c - a )
//
// in this implementation, n is declared as normal, ,a is declared as orient.
//
// obj: object: dojox.gfx3d.Object
this.plus = null;
this.minus = null;
this.object = obj;
var o = outline(obj);
this.orient = o[0];
this.normal = dojox.gfx3d.vector.normalize(o);
},
add: function(obj, outline){
var epsilon = 0.5,
o = outline(obj),
v = dojox.gfx3d.vector,
n = this.normal,
a = this.orient,
BST = dojox.gfx3d.scheduler.BinarySearchTree;
if(
dojo.every(o, function(item){
return Math.floor(epsilon + v.dotProduct(n, v.substract(item, a))) <= 0;
})
){
if(this.minus){
this.minus.add(obj, outline);
}else{
this.minus = new BST(obj, outline);
}
}else if(
dojo.every(o, function(item){
return Math.floor(epsilon + v.dotProduct(n, v.substract(item, a))) >= 0;
})
){
if(this.plus){
this.plus.add(obj, outline);
} else {
this.plus = new BST(obj, outline);
}
}else{
/*
dojo.forEach(o, function(item){
console.debug(v.dotProduct(n, v.substract(item, a)));
});
*/
throw "The case: polygon cross siblings' plate is not implemneted yet";
}
},
iterate: function(outline){
var epsilon = 0.5;
var v = dojox.gfx3d.vector;
var sorted = [];
var subs = null;
// FIXME: using Infinity here?
var view = {x: 0, y: 0, z: -10000};
if(Math.floor( epsilon + v.dotProduct(this.normal, v.substract(view, this.orient))) <= 0){
subs = [this.plus, this.minus];
}else{
subs = [this.minus, this.plus];
}
if(subs[0]){
sorted = sorted.concat(subs[0].iterate());
}
sorted.push(this.object);
if(subs[1]){
sorted = sorted.concat(subs[1].iterate());
}
return sorted;
}
});
dojo.mixin(dojox.gfx3d.drawer, {
conservative: function(todos, objects, viewport){
// console.debug('conservative draw');
dojo.forEach(this.objects, function(item){
item.destroy();
});
dojo.forEach(objects, function(item){
item.draw(viewport.lighting);
});
},
chart: function(todos, objects, viewport){
// NOTE: ondemand may require the todos' objects to use setShape
// to redraw themselves to maintain the z-order.
// console.debug('chart draw');
dojo.forEach(this.todos, function(item){
item.draw(viewport.lighting);
});