码迷,mamicode.com
首页 > 其他好文 > 详细

libgdx学习记录18——Box2d物理引擎

时间:2014-06-09 15:19:09      阅读:321      评论:0      收藏:0      [点我收藏+]

标签:c   style   class   blog   code   java   

libgdx封装了Box2D物理引擎,通过这个引擎能够模拟物理现实,使设计出的游戏更具有真实感。

libgdx中,Box2d程序的大概过程:

1. 创建物理世界world,并设置重力加速度。

2. 创建正交相机,并设置其宽高。Box2d中使用物理世界中米作为单位,而不是图像中的像素,通常设一个比值,这里为了方便,直接设置为10。

3. 创建世界中的动态物体(一般是方块、圆环或其他形状物体)和静态物体(主要指地面、墙壁等)。

4. 在渲染函数中添加world时间布,并利用DebugRenderer将添加的物体绘制出来即可。

具体代码实例:

bubuko.com,布布扣
  1 package com.fxb.newtest;
  2 
  3 import com.badlogic.gdx.ApplicationAdapter;
  4 import com.badlogic.gdx.Gdx;
  5 import com.badlogic.gdx.graphics.GL10;
  6 import com.badlogic.gdx.graphics.OrthographicCamera;
  7 import com.badlogic.gdx.graphics.glutils.ShapeRenderer;
  8 import com.badlogic.gdx.math.Vector2;
  9 import com.badlogic.gdx.physics.box2d.Body;
 10 import com.badlogic.gdx.physics.box2d.BodyDef;
 11 import com.badlogic.gdx.physics.box2d.Box2DDebugRenderer;
 12 import com.badlogic.gdx.physics.box2d.CircleShape;
 13 import com.badlogic.gdx.physics.box2d.Fixture;
 14 import com.badlogic.gdx.physics.box2d.FixtureDef;
 15 import com.badlogic.gdx.physics.box2d.PolygonShape;
 16 import com.badlogic.gdx.physics.box2d.World;
 17 import com.badlogic.gdx.physics.box2d.BodyDef.BodyType;
 18 
 19 public class Lib018_Box2d extends ApplicationAdapter{
 20 
 21     World world;
 22     OrthographicCamera camera;
 23     Box2DDebugRenderer debugRenderer;
 24     ShapeRenderer rend;
 25     
 26     @Override
 27     public void create() {
 28         // TODO Auto-generated method stub
 29         super.create();
 30         
 31         world = new World( new Vector2( 0, -10f ), true );
 32         debugRenderer =new Box2DDebugRenderer();
 33         
 34         camera = new OrthographicCamera();
 35         camera.setToOrtho( false, Gdx.graphics.getWidth()/10, Gdx.graphics.getHeight()/10 );
 36             
 37         
 38         ////create the body of box
 39         BodyDef boxBodyDef = new BodyDef();
 40         boxBodyDef.type = BodyType.DynamicBody;
 41         //boxBodyDef.position.x = -24 + (float)(Math.random() * 48);
 42         //boxBodyDef.position.y = 10 + (float)(Math.random() * 100);
 43         boxBodyDef.position.set( 40, 50 );
 44         Body boxBody = world.createBody(boxBodyDef);
 45         
 46         PolygonShape boxPoly = new PolygonShape();
 47         boxPoly.setAsBox(2, 1);        
 48         boxBody.createFixture(boxPoly, 1);
 49         boxPoly.dispose();
 50             
 51         
 52         /////create the body of circle
 53         BodyDef bodyDef = new BodyDef();
 54         bodyDef.type = BodyType.DynamicBody;
 55         bodyDef.position.set( 60, 100 );
 56         Body bodyCircle = world.createBody( bodyDef );
 57         
 58         CircleShape circle = new CircleShape();
 59         circle.setRadius( 2 );    
 60         FixtureDef fixtureDef = new FixtureDef();
 61         fixtureDef.shape = circle;
 62         fixtureDef.density = 1f;
 63         fixtureDef.friction = 0.4f;
 64         //fixtureDef.restitution = 0.6f;
 65         
 66         bodyCircle.createFixture( fixtureDef );    
 67         circle.dispose();
 68         
 69             
 70         
 71         /////create the body of ground, static body, can‘t move
 72         BodyDef groundBodyDef = new BodyDef();
 73         groundBodyDef.type = BodyType.StaticBody;
 74         groundBodyDef.angle = (float)Math.PI*15/180;
 75         groundBodyDef.position.set( 0, 0 );
 76         Body groundBody = world.createBody( groundBodyDef );
 77         
 78         PolygonShape groundBox = new PolygonShape();
 79         groundBox.setAsBox( camera.viewportWidth+5, 0.5f );
 80         groundBody.createFixture( groundBox, 0.0f );
 81         groundBox.dispose();
 82             
 83     }
 84 
 85     @Override
 86     public void render() {
 87         // TODO Auto-generated method stub
 88         super.render();
 89         //Gdx.gl.glClearColor( 1, 1, 1, 0.2f );
 90         Gdx.gl.glClear( GL10.GL_COLOR_BUFFER_BIT );
 91         
 92         world.step( Gdx.graphics.getDeltaTime(), 6, 2 );
 93         camera.update();
 94         
 95         debugRenderer.render( world, camera.combined );
 96         
 97     }
 98 
 99     @Override
100     public void dispose() {
101         // TODO Auto-generated method stub
102         debugRenderer.dispose();
103         world.dispose();
104         super.dispose();
105     }
106 
107 }
bubuko.com,布布扣

运行结果:

bubuko.com,布布扣

程序中,添加了方块、圆环和地面三个物体,前两个为动态,地面为静态,让地面倾斜15度。

方块和圆环从高空下落到斜坡时,就向下滑动,与我们平常生活常识相吻合。

libgdx学习记录18——Box2d物理引擎,布布扣,bubuko.com

libgdx学习记录18——Box2d物理引擎

标签:c   style   class   blog   code   java   

原文地址:http://www.cnblogs.com/MiniHouse/p/3776573.html

(0)
(0)
   
举报
评论 一句话评论(0
登录后才能评论!
© 2014 mamicode.com 版权所有  联系我们:gaon5@hotmail.com
迷上了代码!