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/*
* Copyright (c) 2007-2009 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 PULLEYS_H
#define PULLEYS_H
class Pulleys : public Test
{
public:
Pulleys()
{
float32 y = 16.0f;
float32 L = 12.0f;
float32 a = 1.0f;
float32 b = 2.0f;
b2Body* ground = NULL;
{
b2BodyDef bd;
ground = m_world->CreateBody(&bd);
b2EdgeShape edge;
edge.Set(b2Vec2(-40.0f, 0.0f), b2Vec2(40.0f, 0.0f));
//ground->CreateFixture(&shape, 0.0f);
b2CircleShape circle;
circle.m_radius = 2.0f;
circle.m_p.Set(-10.0f, y + b + L);
ground->CreateFixture(&circle, 0.0f);
circle.m_p.Set(10.0f, y + b + L);
ground->CreateFixture(&circle, 0.0f);
}
{
b2PolygonShape shape;
shape.SetAsBox(a, b);
b2BodyDef bd;
bd.type = b2_dynamicBody;
//bd.fixedRotation = true;
bd.position.Set(-10.0f, y);
b2Body* body1 = m_world->CreateBody(&bd);
body1->CreateFixture(&shape, 5.0f);
bd.position.Set(10.0f, y);
b2Body* body2 = m_world->CreateBody(&bd);
body2->CreateFixture(&shape, 5.0f);
b2PulleyJointDef pulleyDef;
b2Vec2 anchor1(-10.0f, y + b);
b2Vec2 anchor2(10.0f, y + b);
b2Vec2 groundAnchor1(-10.0f, y + b + L);
b2Vec2 groundAnchor2(10.0f, y + b + L);
pulleyDef.Initialize(body1, body2, groundAnchor1, groundAnchor2, anchor1, anchor2, 1.5f);
m_joint1 = (b2PulleyJoint*)m_world->CreateJoint(&pulleyDef);
}
}
void Keyboard(unsigned char key)
{
switch (key)
{
case 0:
break;
}
}
void Step(Settings* settings)
{
Test::Step(settings);
float32 ratio = m_joint1->GetRatio();
float32 L = m_joint1->GetLengthA() + ratio * m_joint1->GetLengthB();
m_debugDraw.DrawString(5, m_textLine, "L1 + %4.2f * L2 = %4.2f", (float) ratio, (float) L);
m_textLine += 15;
}
static Test* Create()
{
return new Pulleys;
}
b2PulleyJoint* m_joint1;
};
#endif
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