Gears.h
上传用户:gb3593
上传日期:2022-01-07
资源大小:3028k
文件大小:4k
- /*
- * Copyright (c) 2007-2009 Erin Catto http://www.gphysics.com
- *
- * 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 GEARS_H
- #define GEARS_H
- class Gears : public Test
- {
- public:
- Gears()
- {
- b2Body* ground = NULL;
- {
- b2BodyDef bd;
- ground = m_world->CreateBody(&bd);
- b2PolygonShape shape;
- shape.SetAsEdge(b2Vec2(50.0f, 0.0f), b2Vec2(-50.0f, 0.0f));
- ground->CreateFixture(&shape, 0.0f);
- }
- {
- b2CircleShape circle1;
- circle1.m_radius = 1.0f;
- b2CircleShape circle2;
- circle2.m_radius = 2.0f;
-
- b2PolygonShape box;
- box.SetAsBox(0.5f, 5.0f);
- b2BodyDef bd1;
- bd1.type = b2_dynamicBody;
- bd1.position.Set(-3.0f, 12.0f);
- b2Body* body1 = m_world->CreateBody(&bd1);
- body1->CreateFixture(&circle1, 5.0f);
- b2RevoluteJointDef jd1;
- jd1.bodyA = ground;
- jd1.bodyB = body1;
- jd1.localAnchorA = ground->GetLocalPoint(bd1.position);
- jd1.localAnchorB = body1->GetLocalPoint(bd1.position);
- jd1.referenceAngle = body1->GetAngle() - ground->GetAngle();
- m_joint1 = (b2RevoluteJoint*)m_world->CreateJoint(&jd1);
- b2BodyDef bd2;
- bd2.type = b2_dynamicBody;
- bd2.position.Set(0.0f, 12.0f);
- b2Body* body2 = m_world->CreateBody(&bd2);
- body2->CreateFixture(&circle2, 5.0f);
- b2RevoluteJointDef jd2;
- jd2.Initialize(ground, body2, bd2.position);
- m_joint2 = (b2RevoluteJoint*)m_world->CreateJoint(&jd2);
- b2BodyDef bd3;
- bd3.type = b2_dynamicBody;
- bd3.position.Set(2.5f, 12.0f);
- b2Body* body3 = m_world->CreateBody(&bd3);
- body3->CreateFixture(&box, 5.0f);
- b2PrismaticJointDef jd3;
- jd3.Initialize(ground, body3, bd3.position, b2Vec2(0.0f, 1.0f));
- jd3.lowerTranslation = -5.0f;
- jd3.upperTranslation = 5.0f;
- jd3.enableLimit = true;
- m_joint3 = (b2PrismaticJoint*)m_world->CreateJoint(&jd3);
- b2GearJointDef jd4;
- jd4.bodyA = body1;
- jd4.bodyB = body2;
- jd4.joint1 = m_joint1;
- jd4.joint2 = m_joint2;
- jd4.ratio = circle2.m_radius / circle1.m_radius;
- m_joint4 = (b2GearJoint*)m_world->CreateJoint(&jd4);
- b2GearJointDef jd5;
- jd5.bodyA = body2;
- jd5.bodyB = body3;
- jd5.joint1 = m_joint2;
- jd5.joint2 = m_joint3;
- jd5.ratio = -1.0f / circle2.m_radius;
- m_joint5 = (b2GearJoint*)m_world->CreateJoint(&jd5);
- }
- }
- void Keyboard(unsigned char key)
- {
- switch (key)
- {
- case 0:
- break;
- }
- }
- void Step(Settings* settings)
- {
- Test::Step(settings);
- float32 ratio, value;
-
- ratio = m_joint4->GetRatio();
- value = m_joint1->GetJointAngle() + ratio * m_joint2->GetJointAngle();
- m_debugDraw.DrawString(5, m_textLine, "theta1 + %4.2f * theta2 = %4.2f", (float) ratio, (float) value);
- m_textLine += 15;
- ratio = m_joint5->GetRatio();
- value = m_joint2->GetJointAngle() + ratio * m_joint3->GetJointTranslation();
- m_debugDraw.DrawString(5, m_textLine, "theta2 + %4.2f * delta = %4.2f", (float) ratio, (float) value);
- m_textLine += 15;
- }
- static Test* Create()
- {
- return new Gears;
- }
- b2RevoluteJoint* m_joint1;
- b2RevoluteJoint* m_joint2;
- b2PrismaticJoint* m_joint3;
- b2GearJoint* m_joint4;
- b2GearJoint* m_joint5;
- };
- #endif