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/*
* Copyright (c) 2006-2009 Erin Catto http://www.box2d.org
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/
#ifndef BODY_TYPES_H
#define BODY_TYPES_H
class BodyTypes : public Test
{
public:
BodyTypes()
{
b2Body* ground = NULL;
{
b2BodyDef bd;
ground = m_world->CreateBody(&bd);
b2EdgeShape shape;
shape.Set(b2Vec2(-20.0f, 0.0f), b2Vec2(20.0f, 0.0f));
b2FixtureDef fd;
fd.shape = &shape;
ground->CreateFixture(&fd);
}
// Define attachment
{
b2BodyDef bd;
bd.type = b2_dynamicBody;
bd.position.Set(0.0f, 3.0f);
m_attachment = m_world->CreateBody(&bd);
b2PolygonShape shape;
shape.SetAsBox(0.5f, 2.0f);
m_attachment->CreateFixture(&shape, 2.0f);
}
// Define platform
{
b2BodyDef bd;
bd.type = b2_dynamicBody;
bd.position.Set(-4.0f, 5.0f);
m_platform = m_world->CreateBody(&bd);
b2PolygonShape shape;
shape.SetAsBox(0.5f, 4.0f, b2Vec2(4.0f, 0.0f), 0.5f * b2_pi);
b2FixtureDef fd;
fd.shape = &shape;
fd.friction = 0.6f;
fd.density = 2.0f;
m_platform->CreateFixture(&fd);
b2RevoluteJointDef rjd;
rjd.Initialize(m_attachment, m_platform, b2Vec2(0.0f, 5.0f));
rjd.maxMotorTorque = 50.0f;
rjd.enableMotor = true;
m_world->CreateJoint(&rjd);
b2PrismaticJointDef pjd;
pjd.Initialize(ground, m_platform, b2Vec2(0.0f, 5.0f), b2Vec2(1.0f, 0.0f));
pjd.maxMotorForce = 1000.0f;
pjd.enableMotor = true;
pjd.lowerTranslation = -10.0f;
pjd.upperTranslation = 10.0f;
pjd.enableLimit = true;
m_world->CreateJoint(&pjd);
m_speed = 3.0f;
}
// Create a payload
{
b2BodyDef bd;
bd.type = b2_dynamicBody;
bd.position.Set(0.0f, 8.0f);
b2Body* body = m_world->CreateBody(&bd);
b2PolygonShape shape;
shape.SetAsBox(0.75f, 0.75f);
b2FixtureDef fd;
fd.shape = &shape;
fd.friction = 0.6f;
fd.density = 2.0f;
body->CreateFixture(&fd);
}
}
void Keyboard(unsigned char key)
{
switch (key)
{
case 'd':
m_platform->SetType(b2_dynamicBody);
break;
case 's':
m_platform->SetType(b2_staticBody);
break;
case 'k':
m_platform->SetType(b2_kinematicBody);
m_platform->SetLinearVelocity(b2Vec2(-m_speed, 0.0f));
m_platform->SetAngularVelocity(0.0f);
break;
}
}
void Step(Settings* settings)
{
// Drive the kinematic body.
if (m_platform->GetType() == b2_kinematicBody)
{
b2Vec2 p = m_platform->GetTransform().p;
b2Vec2 v = m_platform->GetLinearVelocity();
if ((p.x < -10.0f && v.x < 0.0f) ||
(p.x > 10.0f && v.x > 0.0f))
{
v.x = -v.x;
m_platform->SetLinearVelocity(v);
}
}
Test::Step(settings);
m_debugDraw.DrawString(5, m_textLine, "Keys: (d) dynamic, (s) static, (k) kinematic");
m_textLine += 15;
}
static Test* Create()
{
return new BodyTypes;
}
b2Body* m_attachment;
b2Body* m_platform;
float32 m_speed;
};
#endif
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