Make physics framerate configurable

apps/openmw/mwphysics/physicssystem.cpp

@@ -24,6 +24,7 @@
 #include <components/esm/loadgmst.hpp>
 #include <components/sceneutil/positionattitudetransform.hpp>
 #include <components/sceneutil/unrefqueue.hpp>
+#include <components/settings/settings.hpp>
 
 #include <components/nifosg/particle.hpp> // FindRecIndexVisitor
 
@@ -1357,7 +1358,11 @@ namespace MWPhysics
         mMovementResults.clear();
 
         mTimeAccum += dt;
-        const float physicsDt = 1.f/60.0f;
+
+        static const float physFramerate = Settings::Manager::getFloat("physics framerate", "Physics");
+
+        // Allow to use a physics framerate between 10 and 60 FPS
+        static const float physicsDt = 1.f / std::max(10.f, std::min(60.f, physFramerate));
 
         const int maxAllowedSteps = 20;
         int numSteps = mTimeAccum / (physicsDt);

docs/source/reference/modding/settings/physics.rst

@@ -0,0 +1,13 @@
+Physics Settings
+################
+
+physics framerate
+---------------
+
+:Type:		floating point
+:Range:		10.0 to 60.0
+:Default:	60.0
+
+Allows to set how frequently an engine will do physics calculations. A default value is 60 times per second.
+This setting allows developers with low-clocked CPUs to test an engine.
+Changing from default value can lead to physics bugs. Change this setting on your own risk, and reset a value to default before filling a physics-related bugreport!

files/settings-default.cfg

@@ -277,6 +277,10 @@ camera y multiplier = 1.0
 # Invert the vertical axis while not in GUI mode.
 invert y axis = false
 
+[Physics]
+# Framerate of the physics system
+physics framerate = 60.0
+
 [Saves]
 
 # Name of last character played, and default for loading save files.