refactoring

examples/testbed/framework/body_dragger.cpp

@@ -0,0 +1,98 @@
+/*
+* Copyright (c) 2016-2016 Irlan Robson http://www.irlan.net
+*
+* 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 <testbed/framework/body_dragger.h>
+
+b3BodyDragger::b3BodyDragger(b3Ray3* ray, b3World* world)
+{
+	m_ray = ray;
+	m_world = world;
+	m_shape = nullptr;
+	m_mouseJoint = nullptr;
+}
+
+b3BodyDragger::~b3BodyDragger()
+{
+
+}
+
+bool b3BodyDragger::StartDragging()
+{
+	B3_ASSERT(IsDragging() == false);
+
+	b3RayCastSingleOutput out;
+	if (m_world->RayCastSingle(&out, m_ray->A(), m_ray->B()) == false)
+	{
+		return false;
+	}
+
+	m_x = out.fraction;
+	m_shape = out.shape;
+
+	b3BodyDef bd;
+	b3Body* groundBody = m_world->CreateBody(bd);
+
+	b3Body* body = m_shape->GetBody();
+	body->SetAwake(true);
+
+	b3MouseJointDef jd;
+	jd.bodyA = groundBody;
+	jd.bodyB = body;
+	jd.target = out.point;
+	jd.maxForce = 2000.0f * body->GetMass();
+
+	m_mouseJoint = (b3MouseJoint*)m_world->CreateJoint(jd);
+
+	m_p = body->GetLocalPoint(out.point);
+
+	return true;
+}
+
+void b3BodyDragger::Drag()
+{
+	B3_ASSERT(IsDragging() == true);
+	m_mouseJoint->SetTarget(GetPointB());
+}
+
+void b3BodyDragger::StopDragging()
+{
+	B3_ASSERT(IsDragging() == true);
+	b3Body* groundBody = m_mouseJoint->GetBodyA();
+	m_world->DestroyJoint(m_mouseJoint);
+	m_mouseJoint = nullptr;
+	m_world->DestroyBody(groundBody);
+	m_shape = nullptr;
+}
+
+b3Body* b3BodyDragger::GetBody() const
+{
+	B3_ASSERT(IsDragging() == true);
+	return m_shape->GetBody();
+}
+
+b3Vec3 b3BodyDragger::GetPointA() const
+{
+	B3_ASSERT(IsDragging() == true);
+	return m_shape->GetBody()->GetWorldPoint(m_p);
+}
+
+b3Vec3 b3BodyDragger::GetPointB() const
+{
+	B3_ASSERT(IsDragging() == true);
+	return (1.0f - m_x) * m_ray->A() + m_x * m_ray->B();
+}