topical media & game development

topical media & game development

[] readme course(s) preface I 1 2 II 3 4 III 5 6 7 IV 8 9 10 V 11 12 afterthought(s) appendix reference(s) example(s) resource(s) _

graphic-o3d-samples-io-actors-actor.js / js


  /*
   * Copyright 2009, Google Inc.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are
   * met:
   *
   *     * Redistributions of source code must retain the above copyright
   * notice, this list of conditions and the following disclaimer.
   *     * Redistributions in binary form must reproduce the above
   * copyright notice, this list of conditions and the following disclaimer
   * in the documentation and/or other materials provided with the
   * distribution.
   *     * Neither the name of Google Inc. nor the names of its
   * contributors may be used to endorse or promote products derived from
   * this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */

@fileoverview This file defines the Actor class.

Pulls in all names attributes of a source object and applies them to a target object. Handy for pulling in a bunch of name:value pairs that were passed all at once.


  
  function Actor() {
    // Create some defaults for our "required" attributes.
    this.x = 0;
    this.y = 0;
    this.z = 0;
    this.width = 20;
    this.height = 20;
    this.mapX = 0;
    this.platformID = 0;
    this.rotZ = 0;
    this.frameName = '';
  }
  
  Actor.prototype.absorbNamedValues = function(initObj) {
    for (var key in initObj) {
      this[key] = initObj[key];
    }
  };

Note that for collision detection, all actors are envisioned as 2d rectangles inside a single plane. These rectangles have a width and a height, and their "origin" is on the bottom center of the rectangle. So if you create a new actor, be sure to give it a reasonable width and height.


  
  Actor.prototype.collidesWith = function(otherActor) {
    thisLeft = this.mapX - this.width/2;
    thisRight = this.mapX + this.width/2;
    thisTop = this.z + this.height;
    thisBottom = this.z;
  
    otherLeft = otherActor.mapX - otherActor.width/2;
    otherRight = otherActor.mapX + otherActor.width/2;
    otherTop = otherActor.z + otherActor.height;
    otherBottom = otherActor.z;
  
    // First see if we're not overlapping in any dimension.
    if (thisRight < otherLeft ||
        thisLeft > otherRight ||
        thisBottom > otherTop ||
         thisTop < otherBottom) {
      return false;
    }
  
    // Next check for overlap along X.
    if (thisRight >= otherLeft &&
        thisLeft <= otherRight) {
      // then we're still in the running...
    } else {
      return false;
    }
  
    // Next check for overlap along Y.
    if (thisBottom <= otherTop &&
        thisTop >= otherBottom) {
      return true;
    }
  
    // We're not overlapping in Y, so bomb.
    return false;
  };
  
  Actor.prototype.isHitBySword = function() {
    var isHit = false;
    if (avatar.animation == "Hero_Sword" && avatar.frame > 3) {
      avatar.width += 80;
      avatar.height += avatar.frame * 5;
      if (this.collidesWith(avatar)) {
        var isHit = true;
      }
      avatar.width -= 80;
      avatar.height -= avatar.frame * 5;
    }
    return isHit;
  }
  
  Actor.prototype.isHitByArrow = function() {
    var isHit = false;
    // TODO: Make this allow multiple arrows, perform better, etc.
    if (top.arrowActor != undefined) {
      // If we don't have the same "parentPlatform, meaning we're in different
      // world path space, then we don't collide.
      if (world.platforms[top.arrowActor.platformID].parentID !=
          world.platforms[this.platformID].parentID) {
        return false;
      }
      if (this.collidesWith(top.arrowActor)) {
        var isHit = true;
      }
    }
    return isHit;
  }
  
  Actor.prototype.moveMapX = function(change) {
    var platformAngle = world.platforms[this.platformID].rotZ;
    this.mapX += change;
    this.x += change * Math.cos(platformAngle);
    this.y += change * Math.sin(platformAngle);
  };

[] readme course(s) preface I 1 2 II 3 4 III 5 6 7 IV 8 9 10 V 11 12 afterthought(s) appendix reference(s) example(s) resource(s) _

You may not copy or print any of this material without explicit permission of the author or the publisher. In case of other copyright issues, contact the author.