X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Flibmarklin%2Fsimplephysics.cpp;fp=source%2Flibmarklin%2Fsimplephysics.cpp;h=3dc8e2ef93c2b61ee3c806252b81029aa78f5701;hb=9ddcd066e37e4c72685817c042c30897786ece05;hp=0000000000000000000000000000000000000000;hpb=e94014530a6e28a42bc5678e579ee07e0ee5329b;p=r2c2.git

diff --git a/source/libmarklin/simplephysics.cpp b/source/libmarklin/simplephysics.cpp
new file mode 100644
index 0000000..3dc8e2e
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+++ b/source/libmarklin/simplephysics.cpp
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+/* $Id$
+
+This file is part of the MSP Märklin suite
+Copyright © 2010  Mikkosoft Productions, Mikko Rasa
+Distributed under the GPL
+*/
+
+#include <msp/core/except.h>
+#include <msp/time/units.h>
+#include "simplephysics.h"
+
+using namespace std;
+using namespace Msp;
+
+namespace Marklin {
+
+SimplePhysics::SimplePhysics():
+	target_speed(TrainControl::continuous("speed", -1000, 1000)),
+	accel(0.07),
+	speed(0)
+{
+	target_speed.set(0);
+}
+
+void SimplePhysics::set_control(const string &name, float v)
+{
+	if(name=="speed")
+		target_speed.set(v);
+}
+
+const TrainControl &SimplePhysics::get_control(const string &name) const
+{
+	if(name=="speed")
+		return target_speed;
+	else
+		throw KeyError("Unknown control", name);
+}
+
+float SimplePhysics::get_braking_distance() const
+{
+	return speed*speed/(2*accel);
+}
+
+void SimplePhysics::tick(const Time::TimeDelta &dt)
+{
+	float secs = dt/Time::sec;
+	if(speed<target_speed.value)
+	{
+		speed += secs*accel;
+		if(speed>target_speed.value)
+			speed = target_speed.value;
+	}
+	else if(speed>target_speed.value)
+	{
+		speed -= secs*accel;
+		if(speed<target_speed.value)
+			speed = target_speed.value;
+	}
+}
+
+} // namespace Marklin