box2d 世界:: 一切都是那么轻！
我
在我的世界中使用 box2d 2.1.2 和 cocos2d 0.99.4，一切都很轻， 没有掉落石头或盒子的感觉！ 一切都以相同的速度缓慢下落
b2Vec2 重力； 重力.Set(0.0f,-10.0f); 布尔 doSleep = true; world = new b2World(重力, doSleep);
我的物体：
b2BodyDef *TBodyDef = new b2BodyDef;
TBodyDef->position.Set(100, 200);
b2Body *TBody = world->CreateBody(TBodyDef);
TBody->SetType(b2_dynamicBody);
TBody->SetAwake(true);
b2CircleShape TCircleShape;
TCircleShape.m_radius = 20;
b2FixtureDef TFixtureDef;
TFixtureDef.shape = &TCircleShape;
TFixtureDef.friction = 0.1;
TFixtureDef.density = 0.1;
TFixtureDef.restitution = 1;
TFixtureDef.filter.categoryBits = COLLISION_BIT_GP;
TFixtureDef.filter.maskBits = COLLISION_BIT_TERRAIN;
TBody->CreateFixture(&TFixtureDef);
b2BodyDef *TBodyDef1 = new b2BodyDef;
TBodyDef1->position.Set(200, 200);
b2Body *TBody1 = world->CreateBody(TBodyDef1);
TBody1->SetType(b2_dynamicBody);
TBody1->SetAwake(true);
b2CircleShape TCircleShape1;
TCircleShape1.m_radius = 20;
b2FixtureDef TFixtureDef1;
TFixtureDef1.shape = &TCircleShape;
TFixtureDef1.friction = 0.1;
TFixtureDef1.density = 0.5;
TFixtureDef1.restitution = 1;
TFixtureDef1.filter.categoryBits = COLLISION_BIT_GP;
TFixtureDef1.filter.maskBits = COLLISION_BIT_TERRAIN;
TBody1->CreateFixture(&TFixtureDef1);
和我的脚步：
int32 velocityIterations = 8;
int32 positionIterations = 3;
world->Step(dt, velocityIterations, positionIterations);
密度对下落的速度没有任何改变。 要使它像这样流畅，还缺少什么： 链接文本
谢谢你的帮助
i'm using box2d 2.1.2 with cocos2d 0.99.4
in my world, everything is light,
there is no sensation about dropping a stone or a box !!
everything falling slowly at the same speed
b2Vec2 gravity; gravity.Set(0.0f, -10.0f); bool doSleep = true; world = new b2World(gravity, doSleep);
and my objects :
b2BodyDef *TBodyDef = new b2BodyDef;
TBodyDef->position.Set(100, 200);
b2Body *TBody = world->CreateBody(TBodyDef);
TBody->SetType(b2_dynamicBody);
TBody->SetAwake(true);
b2CircleShape TCircleShape;
TCircleShape.m_radius = 20;
b2FixtureDef TFixtureDef;
TFixtureDef.shape = &TCircleShape;
TFixtureDef.friction = 0.1;
TFixtureDef.density = 0.1;
TFixtureDef.restitution = 1;
TFixtureDef.filter.categoryBits = COLLISION_BIT_GP;
TFixtureDef.filter.maskBits = COLLISION_BIT_TERRAIN;
TBody->CreateFixture(&TFixtureDef);
b2BodyDef *TBodyDef1 = new b2BodyDef;
TBodyDef1->position.Set(200, 200);
b2Body *TBody1 = world->CreateBody(TBodyDef1);
TBody1->SetType(b2_dynamicBody);
TBody1->SetAwake(true);
b2CircleShape TCircleShape1;
TCircleShape1.m_radius = 20;
b2FixtureDef TFixtureDef1;
TFixtureDef1.shape = &TCircleShape;
TFixtureDef1.friction = 0.1;
TFixtureDef1.density = 0.5;
TFixtureDef1.restitution = 1;
TFixtureDef1.filter.categoryBits = COLLISION_BIT_GP;
TFixtureDef1.filter.maskBits = COLLISION_BIT_TERRAIN;
TBody1->CreateFixture(&TFixtureDef1);
and my step :
int32 velocityIterations = 8;
int32 positionIterations = 3;
world->Step(dt, velocityIterations, positionIterations);
density changes nothing about the speed of falling.
what is missing to make it as fluid as this :
link text
thank you for your help
如果你对这篇内容有疑问，欢迎到本站社区发帖提问 参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。
绑定邮箱获取回复消息
由于您还没有绑定你的真实邮箱，如果其他用户或者作者回复了您的评论，将不能在第一时间通知您！
发布评论
评论（1）
物体的密度不会影响它下落的速度。
消除空气阻力和其他通常可以忽略不计的影响，所有物体都会以相同的速度下落。
如何测试：拿起一些轻的东西（例如你朋友的 iPhone 4）和一些重的东西（你的旧 CRT），然后将它们同时扔出窗外。
An objects density does not affect the speed it falls at.
Negating air-resistance and other generally negligible effects all objects DO fall at the same speed.
How to test this: Pick up something light (e.g. your friends iPhone 4) and something heavy (your old CRT) and drop them out of a window at exactly the same time.