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-rw-r--r--Source/3rdParty/Box2D/Rope/b2Rope.cpp259
1 files changed, 0 insertions, 259 deletions
diff --git a/Source/3rdParty/Box2D/Rope/b2Rope.cpp b/Source/3rdParty/Box2D/Rope/b2Rope.cpp
deleted file mode 100644
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--- a/Source/3rdParty/Box2D/Rope/b2Rope.cpp
+++ /dev/null
@@ -1,259 +0,0 @@
-/*
-* Copyright (c) 2011 Erin Catto http://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.
-*/
-
-#include "Box2D/Rope/b2Rope.h"
-#include "Box2D/Common/b2Draw.h"
-
-b2Rope::b2Rope()
-{
- m_count = 0;
- m_ps = nullptr;
- m_p0s = nullptr;
- m_vs = nullptr;
- m_ims = nullptr;
- m_Ls = nullptr;
- m_as = nullptr;
- m_gravity.SetZero();
- m_k2 = 1.0f;
- m_k3 = 0.1f;
-}
-
-b2Rope::~b2Rope()
-{
- b2Free(m_ps);
- b2Free(m_p0s);
- b2Free(m_vs);
- b2Free(m_ims);
- b2Free(m_Ls);
- b2Free(m_as);
-}
-
-void b2Rope::Initialize(const b2RopeDef* def)
-{
- b2Assert(def->count >= 3);
- m_count = def->count;
- m_ps = (b2Vec2*)b2Alloc(m_count * sizeof(b2Vec2));
- m_p0s = (b2Vec2*)b2Alloc(m_count * sizeof(b2Vec2));
- m_vs = (b2Vec2*)b2Alloc(m_count * sizeof(b2Vec2));
- m_ims = (float32*)b2Alloc(m_count * sizeof(float32));
-
- for (int32 i = 0; i < m_count; ++i)
- {
- m_ps[i] = def->vertices[i];
- m_p0s[i] = def->vertices[i];
- m_vs[i].SetZero();
-
- float32 m = def->masses[i];
- if (m > 0.0f)
- {
- m_ims[i] = 1.0f / m;
- }
- else
- {
- m_ims[i] = 0.0f;
- }
- }
-
- int32 count2 = m_count - 1;
- int32 count3 = m_count - 2;
- m_Ls = (float32*)b2Alloc(count2 * sizeof(float32));
- m_as = (float32*)b2Alloc(count3 * sizeof(float32));
-
- for (int32 i = 0; i < count2; ++i)
- {
- b2Vec2 p1 = m_ps[i];
- b2Vec2 p2 = m_ps[i+1];
- m_Ls[i] = b2Distance(p1, p2);
- }
-
- for (int32 i = 0; i < count3; ++i)
- {
- b2Vec2 p1 = m_ps[i];
- b2Vec2 p2 = m_ps[i + 1];
- b2Vec2 p3 = m_ps[i + 2];
-
- b2Vec2 d1 = p2 - p1;
- b2Vec2 d2 = p3 - p2;
-
- float32 a = b2Cross(d1, d2);
- float32 b = b2Dot(d1, d2);
-
- m_as[i] = b2Atan2(a, b);
- }
-
- m_gravity = def->gravity;
- m_damping = def->damping;
- m_k2 = def->k2;
- m_k3 = def->k3;
-}
-
-void b2Rope::Step(float32 h, int32 iterations)
-{
- if (h == 0.0)
- {
- return;
- }
-
- float32 d = expf(- h * m_damping);
-
- for (int32 i = 0; i < m_count; ++i)
- {
- m_p0s[i] = m_ps[i];
- if (m_ims[i] > 0.0f)
- {
- m_vs[i] += h * m_gravity;
- }
- m_vs[i] *= d;
- m_ps[i] += h * m_vs[i];
-
- }
-
- for (int32 i = 0; i < iterations; ++i)
- {
- SolveC2();
- SolveC3();
- SolveC2();
- }
-
- float32 inv_h = 1.0f / h;
- for (int32 i = 0; i < m_count; ++i)
- {
- m_vs[i] = inv_h * (m_ps[i] - m_p0s[i]);
- }
-}
-
-void b2Rope::SolveC2()
-{
- int32 count2 = m_count - 1;
-
- for (int32 i = 0; i < count2; ++i)
- {
- b2Vec2 p1 = m_ps[i];
- b2Vec2 p2 = m_ps[i + 1];
-
- b2Vec2 d = p2 - p1;
- float32 L = d.Normalize();
-
- float32 im1 = m_ims[i];
- float32 im2 = m_ims[i + 1];
-
- if (im1 + im2 == 0.0f)
- {
- continue;
- }
-
- float32 s1 = im1 / (im1 + im2);
- float32 s2 = im2 / (im1 + im2);
-
- p1 -= m_k2 * s1 * (m_Ls[i] - L) * d;
- p2 += m_k2 * s2 * (m_Ls[i] - L) * d;
-
- m_ps[i] = p1;
- m_ps[i + 1] = p2;
- }
-}
-
-void b2Rope::SetAngle(float32 angle)
-{
- int32 count3 = m_count - 2;
- for (int32 i = 0; i < count3; ++i)
- {
- m_as[i] = angle;
- }
-}
-
-void b2Rope::SolveC3()
-{
- int32 count3 = m_count - 2;
-
- for (int32 i = 0; i < count3; ++i)
- {
- b2Vec2 p1 = m_ps[i];
- b2Vec2 p2 = m_ps[i + 1];
- b2Vec2 p3 = m_ps[i + 2];
-
- float32 m1 = m_ims[i];
- float32 m2 = m_ims[i + 1];
- float32 m3 = m_ims[i + 2];
-
- b2Vec2 d1 = p2 - p1;
- b2Vec2 d2 = p3 - p2;
-
- float32 L1sqr = d1.LengthSquared();
- float32 L2sqr = d2.LengthSquared();
-
- if (L1sqr * L2sqr == 0.0f)
- {
- continue;
- }
-
- float32 a = b2Cross(d1, d2);
- float32 b = b2Dot(d1, d2);
-
- float32 angle = b2Atan2(a, b);
-
- b2Vec2 Jd1 = (-1.0f / L1sqr) * d1.Skew();
- b2Vec2 Jd2 = (1.0f / L2sqr) * d2.Skew();
-
- b2Vec2 J1 = -Jd1;
- b2Vec2 J2 = Jd1 - Jd2;
- b2Vec2 J3 = Jd2;
-
- float32 mass = m1 * b2Dot(J1, J1) + m2 * b2Dot(J2, J2) + m3 * b2Dot(J3, J3);
- if (mass == 0.0f)
- {
- continue;
- }
-
- mass = 1.0f / mass;
-
- float32 C = angle - m_as[i];
-
- while (C > b2_pi)
- {
- angle -= 2 * b2_pi;
- C = angle - m_as[i];
- }
-
- while (C < -b2_pi)
- {
- angle += 2.0f * b2_pi;
- C = angle - m_as[i];
- }
-
- float32 impulse = - m_k3 * mass * C;
-
- p1 += (m1 * impulse) * J1;
- p2 += (m2 * impulse) * J2;
- p3 += (m3 * impulse) * J3;
-
- m_ps[i] = p1;
- m_ps[i + 1] = p2;
- m_ps[i + 2] = p3;
- }
-}
-
-void b2Rope::Draw(b2Draw* draw) const
-{
- b2Color c(0.4f, 0.5f, 0.7f);
-
- for (int32 i = 0; i < m_count - 1; ++i)
- {
- draw->DrawSegment(m_ps[i], m_ps[i+1], c);
- }
-}