|  | /*
* 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 WEB_H
#define WEB_H
// This tests distance joints, body destruction, and joint destruction.
class Web : public Test
{
public:
    Web()
    {
        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(0.5f, 0.5f);
            b2BodyDef bd;
            bd.type = b2_dynamicBody;
            bd.position.Set(-5.0f, 5.0f);
            m_bodies[0] = m_world->CreateBody(&bd);
            m_bodies[0]->CreateFixture(&shape, 5.0f);
            bd.position.Set(5.0f, 5.0f);
            m_bodies[1] = m_world->CreateBody(&bd);
            m_bodies[1]->CreateFixture(&shape, 5.0f);
            bd.position.Set(5.0f, 15.0f);
            m_bodies[2] = m_world->CreateBody(&bd);
            m_bodies[2]->CreateFixture(&shape, 5.0f);
            bd.position.Set(-5.0f, 15.0f);
            m_bodies[3] = m_world->CreateBody(&bd);
            m_bodies[3]->CreateFixture(&shape, 5.0f);
            b2DistanceJointDef jd;
            b2Vec2 p1, p2, d;
            jd.frequencyHz = 2.0f;
            jd.dampingRatio = 0.0f;
            jd.bodyA = ground;
            jd.bodyB = m_bodies[0];
            jd.localAnchorA.Set(-10.0f, 0.0f);
            jd.localAnchorB.Set(-0.5f, -0.5f);
            p1 = jd.bodyA->GetWorldPoint(jd.localAnchorA);
            p2 = jd.bodyB->GetWorldPoint(jd.localAnchorB);
            d = p2 - p1;
            jd.length = d.Length();
            m_joints[0] = m_world->CreateJoint(&jd);
            jd.bodyA = ground;
            jd.bodyB = m_bodies[1];
            jd.localAnchorA.Set(10.0f, 0.0f);
            jd.localAnchorB.Set(0.5f, -0.5f);
            p1 = jd.bodyA->GetWorldPoint(jd.localAnchorA);
            p2 = jd.bodyB->GetWorldPoint(jd.localAnchorB);
            d = p2 - p1;
            jd.length = d.Length();
            m_joints[1] = m_world->CreateJoint(&jd);
            jd.bodyA = ground;
            jd.bodyB = m_bodies[2];
            jd.localAnchorA.Set(10.0f, 20.0f);
            jd.localAnchorB.Set(0.5f, 0.5f);
            p1 = jd.bodyA->GetWorldPoint(jd.localAnchorA);
            p2 = jd.bodyB->GetWorldPoint(jd.localAnchorB);
            d = p2 - p1;
            jd.length = d.Length();
            m_joints[2] = m_world->CreateJoint(&jd);
            jd.bodyA = ground;
            jd.bodyB = m_bodies[3];
            jd.localAnchorA.Set(-10.0f, 20.0f);
            jd.localAnchorB.Set(-0.5f, 0.5f);
            p1 = jd.bodyA->GetWorldPoint(jd.localAnchorA);
            p2 = jd.bodyB->GetWorldPoint(jd.localAnchorB);
            d = p2 - p1;
            jd.length = d.Length();
            m_joints[3] = m_world->CreateJoint(&jd);
            jd.bodyA = m_bodies[0];
            jd.bodyB = m_bodies[1];
            jd.localAnchorA.Set(0.5f, 0.0f);
            jd.localAnchorB.Set(-0.5f, 0.0f);;
            p1 = jd.bodyA->GetWorldPoint(jd.localAnchorA);
            p2 = jd.bodyB->GetWorldPoint(jd.localAnchorB);
            d = p2 - p1;
            jd.length = d.Length();
            m_joints[4] = m_world->CreateJoint(&jd);
            jd.bodyA = m_bodies[1];
            jd.bodyB = m_bodies[2];
            jd.localAnchorA.Set(0.0f, 0.5f);
            jd.localAnchorB.Set(0.0f, -0.5f);
            p1 = jd.bodyA->GetWorldPoint(jd.localAnchorA);
            p2 = jd.bodyB->GetWorldPoint(jd.localAnchorB);
            d = p2 - p1;
            jd.length = d.Length();
            m_joints[5] = m_world->CreateJoint(&jd);
            jd.bodyA = m_bodies[2];
            jd.bodyB = m_bodies[3];
            jd.localAnchorA.Set(-0.5f, 0.0f);
            jd.localAnchorB.Set(0.5f, 0.0f);
            p1 = jd.bodyA->GetWorldPoint(jd.localAnchorA);
            p2 = jd.bodyB->GetWorldPoint(jd.localAnchorB);
            d = p2 - p1;
            jd.length = d.Length();
            m_joints[6] = m_world->CreateJoint(&jd);
            jd.bodyA = m_bodies[3];
            jd.bodyB = m_bodies[0];
            jd.localAnchorA.Set(0.0f, -0.5f);
            jd.localAnchorB.Set(0.0f, 0.5f);
            p1 = jd.bodyA->GetWorldPoint(jd.localAnchorA);
            p2 = jd.bodyB->GetWorldPoint(jd.localAnchorB);
            d = p2 - p1;
            jd.length = d.Length();
            m_joints[7] = m_world->CreateJoint(&jd);
        }
    }
    void Keyboard(unsigned char key)
    {
        switch (key)
        {
        case 'b':
            for (int32 i = 0; i < 4; ++i)
            {
                if (m_bodies[i])
                {
                    m_world->DestroyBody(m_bodies[i]);
                    m_bodies[i] = NULL;
                    break;
                }
            }
            break;
        case 'j':
            for (int32 i = 0; i < 8; ++i)
            {
                if (m_joints[i])
                {
                    m_world->DestroyJoint(m_joints[i]);
                    m_joints[i] = NULL;
                    break;
                }
            }
            break;
        }
    }
    void Step(Settings* settings)
    {
        Test::Step(settings);
        m_debugDraw.DrawString(5, m_textLine, "This demonstrates a soft distance joint.");
        m_textLine += 15;
        m_debugDraw.DrawString(5, m_textLine, "Press: (b) to delete a body, (j) to delete a joint");
        m_textLine += 15;
    }
    void JointDestroyed(b2Joint* joint)
    {
        for (int32 i = 0; i < 8; ++i)
        {
            if (m_joints[i] == joint)
            {
                m_joints[i] = NULL;
                break;
            }
        }
    }
    static Test* Create()
    {
        return new Web;
    }
    b2Body* m_bodies[4];
    b2Joint* m_joints[8];
};
#endif
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