friction.cpp

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// MIT License

// Copyright (c) 2019 Erin Catto

// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:

// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

#include "test.h"

class Friction : public Test
{
public:

        Friction()
        {
                {
                        b2BodyDef bd;
                        b2Body* ground = m_world->CreateBody(&bd);

                        b2EdgeShape shape;
                        shape.SetTwoSided(b2Vec2(-40.0f, 0.0f), b2Vec2(40.0f, 0.0f));
                        ground->CreateFixture(&shape, 0.0f);
                }

                {
                        b2PolygonShape shape;
                        shape.SetAsBox(13.0f, 0.25f);

                        b2BodyDef bd;
                        bd.position.Set(-4.0f, 22.0f);
                        bd.angle = -0.25f;

                        b2Body* ground = m_world->CreateBody(&bd);
                        ground->CreateFixture(&shape, 0.0f);
                }

                {
                        b2PolygonShape shape;
                        shape.SetAsBox(0.25f, 1.0f);

                        b2BodyDef bd;
                        bd.position.Set(10.5f, 19.0f);

                        b2Body* ground = m_world->CreateBody(&bd);
                        ground->CreateFixture(&shape, 0.0f);
                }

                {
                        b2PolygonShape shape;
                        shape.SetAsBox(13.0f, 0.25f);

                        b2BodyDef bd;
                        bd.position.Set(4.0f, 14.0f);
                        bd.angle = 0.25f;

                        b2Body* ground = m_world->CreateBody(&bd);
                        ground->CreateFixture(&shape, 0.0f);
                }

                {
                        b2PolygonShape shape;
                        shape.SetAsBox(0.25f, 1.0f);

                        b2BodyDef bd;
                        bd.position.Set(-10.5f, 11.0f);

                        b2Body* ground = m_world->CreateBody(&bd);
                        ground->CreateFixture(&shape, 0.0f);
                }

                {
                        b2PolygonShape shape;
                        shape.SetAsBox(13.0f, 0.25f);

                        b2BodyDef bd;
                        bd.position.Set(-4.0f, 6.0f);
                        bd.angle = -0.25f;

                        b2Body* ground = m_world->CreateBody(&bd);
                        ground->CreateFixture(&shape, 0.0f);
                }

                {
                        b2PolygonShape shape;
                        shape.SetAsBox(0.5f, 0.5f);

                        b2FixtureDef fd;
                        fd.shape = &shape;
                        fd.density = 25.0f;

                        float friction[5] = {0.75f, 0.5f, 0.35f, 0.1f, 0.0f};

                        for (int i = 0; i < 5; ++i)
                        {
                                b2BodyDef bd;
                                bd.type = b2_dynamicBody;
                                bd.position.Set(-15.0f + 4.0f * i, 28.0f);
                                b2Body* body = m_world->CreateBody(&bd);

                                fd.friction = friction[i];
                                body->CreateFixture(&fd);
                        }
                }
        }

        static Test* Create()
        {
                return new Friction;
        }
};

static int testIndex = RegisterTest("Forces", "Friction", Friction::Create);