/* * 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 PRISMATIC_H #define PRISMATIC_H // The motor in this test gets smoother with higher velocity iterations. class Prismatic : public Test { public: Prismatic() { b2Body* ground = NULL; { b2BodyDef bd; ground = m_world->CreateBody(&bd); b2EdgeShape shape; shape.Set(b2Vec2(-40.0f, 0.0f), b2Vec2(40.0f, 0.0f)); ground->CreateFixture(&shape, 0.0f); } { b2PolygonShape shape; shape.SetAsBox(2.0f, 0.5f); b2BodyDef bd; bd.type = b2_dynamicBody; bd.position.Set(-10.0f, 10.0f); bd.angle = 0.5f * b2_pi; bd.allowSleep = false; b2Body* body = m_world->CreateBody(&bd); body->CreateFixture(&shape, 5.0f); b2PrismaticJointDef pjd; // Bouncy limit b2Vec2 axis(2.0f, 1.0f); axis.Normalize(); pjd.Initialize(ground, body, b2Vec2(0.0f, 0.0f), axis); // Non-bouncy limit //pjd.Initialize(ground, body, b2Vec2(-10.0f, 10.0f), b2Vec2(1.0f, 0.0f)); pjd.motorSpeed = 10.0f; pjd.maxMotorForce = 10000.0f; pjd.enableMotor = true; pjd.lowerTranslation = 0.0f; pjd.upperTranslation = 20.0f; pjd.enableLimit = true; m_joint = (b2PrismaticJoint*)m_world->CreateJoint(&pjd); } } void Keyboard(unsigned char key) { switch (key) { case 'l': m_joint->EnableLimit(!m_joint->IsLimitEnabled()); break; case 'm': m_joint->EnableMotor(!m_joint->IsMotorEnabled()); break; case 's': m_joint->SetMotorSpeed(-m_joint->GetMotorSpeed()); break; } } void Step(Settings* settings) { Test::Step(settings); m_debugDraw.DrawString(5, m_textLine, "Keys: (l) limits, (m) motors, (s) speed"); m_textLine += 15; float32 force = m_joint->GetMotorForce(settings->hz); m_debugDraw.DrawString(5, m_textLine, "Motor Force = %4.0f", (float) force); m_textLine += 15; } static Test* Create() { return new Prismatic; } b2PrismaticJoint* m_joint; }; #endif