Added Box2D

external/Box2D-2.3.1/Box2D/Testbed/Tests/MotorJoint.h

@@ -0,0 +1,114 @@
+/*
+* Copyright (c) 2006-2012 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 MOTOR_JOINT_H
+#define MOTOR_JOINT_H
+
+/// This test shows how to use a motor joint. A motor joint
+/// can be used to animate a dynamic body. With finite motor forces
+/// the body can be blocked by collision with other bodies.
+class MotorJoint : public Test
+{
+public:
+	MotorJoint()
+	{
+		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 motorized body
+		{
+			b2BodyDef bd;
+			bd.type = b2_dynamicBody;
+			bd.position.Set(0.0f, 8.0f);
+			b2Body* body = m_world->CreateBody(&bd);
+
+			b2PolygonShape shape;
+			shape.SetAsBox(2.0f, 0.5f);
+
+			b2FixtureDef fd;
+			fd.shape = &shape;
+			fd.friction = 0.6f;
+			fd.density = 2.0f;
+			body->CreateFixture(&fd);
+
+			b2MotorJointDef mjd;
+			mjd.Initialize(ground, body);
+			mjd.maxForce = 1000.0f;
+			mjd.maxTorque = 1000.0f;
+			m_joint = (b2MotorJoint*)m_world->CreateJoint(&mjd);
+		}
+
+		m_go = false;
+		m_time = 0.0f;
+	}
+
+	void Keyboard(int key)
+	{
+		switch (key)
+		{
+		case GLFW_KEY_S:
+			m_go = !m_go;
+			break;
+		}
+	}
+
+	void Step(Settings* settings)
+	{
+		if (m_go && settings->hz > 0.0f)
+		{
+			m_time += 1.0f / settings->hz;
+		}
+
+		b2Vec2 linearOffset;
+		linearOffset.x = 6.0f * sinf(2.0f * m_time);
+		linearOffset.y = 8.0f + 4.0f * sinf(1.0f * m_time);
+		
+		float32 angularOffset = 4.0f * m_time;
+
+		m_joint->SetLinearOffset(linearOffset);
+		m_joint->SetAngularOffset(angularOffset);
+
+		g_debugDraw.DrawPoint(linearOffset, 4.0f, b2Color(0.9f, 0.9f, 0.9f));
+
+		Test::Step(settings);
+		g_debugDraw.DrawString(5, m_textLine, "Keys: (s) pause");
+		m_textLine += 15;
+	}
+
+	static Test* Create()
+	{
+		return new MotorJoint;
+	}
+
+	b2MotorJoint* m_joint;
+	float32 m_time;
+	bool m_go;
+};
+
+#endif