102 lines
2.7 KiB
C
102 lines
2.7 KiB
C
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/*
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* Copyright (c) 2011 Erin Catto http://box2d.org
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*
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* This software is provided 'as-is', without any express or implied
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* warranty. In no event will the authors be held liable for any damages
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* arising from the use of this software.
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* Permission is granted to anyone to use this software for any purpose,
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* including commercial applications, and to alter it and redistribute it
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* freely, subject to the following restrictions:
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* 1. The origin of this software must not be misrepresented; you must not
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* claim that you wrote the original software. If you use this software
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* in a product, an acknowledgment in the product documentation would be
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* appreciated but is not required.
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* 2. Altered source versions must be plainly marked as such, and must not be
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* misrepresented as being the original software.
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* 3. This notice may not be removed or altered from any source distribution.
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*/
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#ifndef ROPE_H
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#define ROPE_H
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///
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class Rope : public Test
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{
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public:
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Rope()
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{
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const int32 N = 40;
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b2Vec2 vertices[N];
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float32 masses[N];
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for (int32 i = 0; i < N; ++i)
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{
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vertices[i].Set(0.0f, 20.0f - 0.25f * i);
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masses[i] = 1.0f;
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}
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masses[0] = 0.0f;
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masses[1] = 0.0f;
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b2RopeDef def;
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def.vertices = vertices;
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def.count = N;
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def.gravity.Set(0.0f, -10.0f);
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def.masses = masses;
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def.damping = 0.1f;
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def.k2 = 1.0f;
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def.k3 = 0.5f;
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m_rope.Initialize(&def);
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m_angle = 0.0f;
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m_rope.SetAngle(m_angle);
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}
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void Keyboard(unsigned char key)
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{
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switch (key)
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{
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case 'q':
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m_angle = b2Max(-b2_pi, m_angle - 0.05f * b2_pi);
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m_rope.SetAngle(m_angle);
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break;
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case 'e':
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m_angle = b2Min(b2_pi, m_angle + 0.05f * b2_pi);
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m_rope.SetAngle(m_angle);
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break;
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}
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}
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void Step(Settings* settings)
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{
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float32 dt = settings->hz > 0.0f ? 1.0f / settings->hz : 0.0f;
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if (settings->pause == 1 && settings->singleStep == 0)
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{
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dt = 0.0f;
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}
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m_rope.Step(dt, 1);
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Test::Step(settings);
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m_rope.Draw(&m_debugDraw);
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m_debugDraw.DrawString(5, m_textLine, "Press (q,e) to adjust target angle");
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m_textLine += 15;
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m_debugDraw.DrawString(5, m_textLine, "Target angle = %g degrees", m_angle * 180.0f / b2_pi);
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m_textLine += 15;
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}
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static Test* Create()
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{
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return new Rope;
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}
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b2Rope m_rope;
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float32 m_angle;
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};
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#endif
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