/**
* @fileoverview phoria - View Control. Helpers to control the view via mouse, provide high-level mouse events.
* Reverse object selection (entity picking) - contribution from Ruan Moolman.
* @author Kevin Roast
* @date 26th Jan 2014
*
* @module View
*/
/**
* View helper class. Provides view related utilities such as high-level event handling. Reverse object selection (entity picking).
*
* @class View
*/
(function() {
"use strict";
Phoria.View = {};
Phoria.View.events = {};
/**
* @method addMouseEvents
*
* @param el
* @param fnOnClick
*/
Phoria.View.addMouseEvents = function addMouseEvents(el, fnOnClick)
{
if (el.id)
{
// mouse rotation and position tracking instance
var mouse = {
velocityH: 0, // final target value from horizontal mouse movement
velocityLastH: 0,
positionX: 0,
clickPositionX: 0, // last mouse click position
velocityV: 0, // final target value from vertical mouse movement
velocityLastV: 0,
positionY: 0,
clickPositionY: 0 // last mouse click position
};
// set object reference for our events
Phoria.View.events[el.id] = mouse;
mouse.onMouseMove = function onMouseMove(evt) {
mouse.positionX = evt.clientX;
mouse.velocityH = mouse.velocityLastH + (mouse.positionX - mouse.clickPositionX) * 0.5;
mouse.positionY = evt.clientY;
mouse.velocityV = mouse.velocityLastV + (mouse.positionY - mouse.clickPositionY) * 0.5;
};
mouse.onMouseUp = function onMouseUp(evt) {
el.removeEventListener('mousemove', mouse.onMouseMove, false);
};
mouse.onMouseOut = function onMouseOut(evt) {
el.removeEventListener('mousemove', mouse.onMouseMove, false);
};
mouse.onMouseDown = function onMouseDown(evt) {
evt.preventDefault();
el.addEventListener('mousemove', mouse.onMouseMove, false);
mouse.clickPositionX = evt.clientX;
mouse.velocityLastH = mouse.velocityH;
mouse.clickPositionY = evt.clientY;
mouse.velocityLastV = mouse.velocityV;
};
el.addEventListener('mousedown', mouse.onMouseDown, false);
el.addEventListener('mouseup', mouse.onMouseUp, false);
el.addEventListener('mouseout', mouse.onMouseOut, false);
// add click handler if supplied
if (fnOnClick) el.addEventListener('click', fnOnClick, false);
return mouse;
}
}
/**
* @method removeMouseEvents
*
* @param el
* @param fnOnClick
*/
Phoria.View.removeMouseEvents = function removeMouseEvents(el, fnOnClick)
{
if (el.id)
{
var mouse = Phoria.View.events[el.id];
if (mouse)
{
el.removeEventListener('mousemove', mouse.onMouseMove, false);
el.removeEventListener('mousedown', mouse.onMouseDown, false);
el.removeEventListener('mouseup', mouse.onMouseUp, false);
el.removeEventListener('mouseout', mouse.onMouseOut, false);
if (fnOnClick) el.removeEventListener('click', fnOnClick, false);
Phoria.View.events[el.id] = null;
}
}
}
/**
* @method getMouse
*
* @param el
*/
Phoria.View.getMouse = function getMouse(el)
{
return Phoria.View.events[el.id];
}
/**
* @method calculateClickPointAndVector
*
* @param scene
* @param mousex
* @param mousey
*/
Phoria.View.calculateClickPointAndVector = function calculateClickPointAndVector(scene, mousex, mousey)
{
var camLookAt = vec3.fromValues(
scene.camera.lookat.x,
scene.camera.lookat.y,
scene.camera.lookat.z);
var camOff = vec3.subtract(vec3.create(), scene._cameraPosition, camLookAt);
// get pixels per unit at click plane (plane normal to camera direction going through the camera focus point)
var pixelsPerUnit = (scene.viewport.height / 2) / (vec3.length(camOff) * Math.tan((scene.perspective.fov / 180 * Math.PI) / 2));
// calculate world units (from the centre of canvas) corresponding to the mouse click position
var dif = vec2.fromValues(mousex - (scene.viewport.width / 2), mousey - (scene.viewport.height / 2));
vec2.subtract(dif, dif, new vec2.fromValues(8, 8)); // calibrate
var units = vec2.create();
vec2.scale(units, dif, 1 / pixelsPerUnit);
// move click point horizontally on click plane by the number of units calculated from the x offset of the mouse click
var upVector = vec3.fromValues(scene.camera.up.x, scene.camera.up.y, scene.camera.up.z);
var normalVectorSide = vec3.create();
vec3.cross(normalVectorSide, camOff, upVector);
vec3.normalize(normalVectorSide, normalVectorSide);
var clickPoint = vec3.scaleAndAdd(vec3.create(), camLookAt, normalVectorSide, units[0]);
// move click point vertically on click plane by the number of units calculated from the y offset of the mouse click
var normalVectorUp = vec3.create();
vec3.cross(normalVectorUp, normalVectorSide, camOff);
vec3.normalize(normalVectorUp, normalVectorUp);
vec3.scale(normalVectorUp, normalVectorUp, units[1]);
vec3.subtract(clickPoint, clickPoint, normalVectorUp);
// calculate click vector (vector from click point to the camera's position)
var camVector = vec3.add(vec3.create(), camLookAt, camOff);
return {
clickPoint: clickPoint,
clickVector: vec3.subtract(vec3.create(), clickPoint, camVector)
};
}
Phoria.View.getIntersectedObjects = function getIntersectedObjects(scene, clickPoint, clickVector)
{
var intersections = [], obj, polygonNormal, polygonPoint, polygonCoords, polygonPlaneIntersection, pointVector;
// Go through all the appropriate objects
var objects = scene.renderlist;
for (var n = 0, obj; n < objects.length; n++)
{
obj = objects[n];
// only consider solid objects
if (obj.style.drawmode !== "solid") continue;
// Go through all the polygons of an object
for (var m = 0; m < obj.polygons.length; m++)
{
polygonNormal = vec3.clone(obj.polygons[m]._worldnormal);
polygonPoint = vec3.clone(obj._worldcoords[obj.polygons[m].vertices[0]]);
// Get the point where the line intersectects the polygon's plane
polygonPlaneIntersection = Phoria.Util.planeLineIntersection(polygonNormal, polygonPoint, clickVector, clickPoint);
// if the intersection is null, it means the line does not intersect the plane
if (polygonPlaneIntersection !== null)
{
// Check if the intersection is inside the polygon
if (Phoria.Util.intersectionInsidePolygon(obj.polygons[m], obj._worldcoords, polygonPlaneIntersection))
{
// add intersection to the array being returned
var returnObject = {
entity: obj,
polygonIndex: m,
intersectionPoint: polygonPlaneIntersection
};
intersections.push(returnObject);
}
}
}
}
// calculate distance to each intersection from camera's position
for (var i = 0; i < intersections.length; i++)
{
intersections[i].distance = vec3.distance(scene._cameraPosition, intersections[i].intersectionPoint);
}
// sort intersection points from closest to farthest
for (var i = 0; i < intersections.length - 1; i++)
{
for (var j = i + 1, keepVal; j < intersections.length; j++)
{
if (intersections[i].distance >= intersections[j].distance)
{
keepVal = intersections[j];
intersections[j] = intersections[i];
intersections[i] = keepVal;
}
}
}
// return list of all intersections
return intersections;
}
})();
