diff --git a/source/graphics/CinemaTrack.cpp b/source/graphics/CinemaTrack.cpp
index 1be4f6b9bd..c16fe9ff3c 100644
--- a/source/graphics/CinemaTrack.cpp
+++ b/source/graphics/CinemaTrack.cpp
@@ -205,7 +205,7 @@ float CCinemaPath::EaseCircle(float t) const
 
 float CCinemaPath::EaseSine(float t) const
 {
-     t = 1.0f - cos(t * M_PI/2);
+     t = 1.0f - cos(t * (float)M_PI/2);
      if(m_GrowthCount > 1.0f)
 	 {
 		 m_GrowthCount--;
diff --git a/source/graphics/MapReader.cpp b/source/graphics/MapReader.cpp
index c176b10166..ddde2504dd 100644
--- a/source/graphics/MapReader.cpp
+++ b/source/graphics/MapReader.cpp
@@ -1110,7 +1110,7 @@ int CXMLReader::ReadNonEntities(XMBElement parent, double end_time)
 			if (unit)
 			{
 				CMatrix3D m;
-				m.SetYRotation(Orientation + M_PI);
+				m.SetYRotation(Orientation + (float)M_PI);
 				m.Translate(Position);
 				unit->GetModel()->SetTransform(m);
 
diff --git a/source/graphics/MapWriter.cpp b/source/graphics/MapWriter.cpp
index 76961b66f9..e604b7c6f6 100644
--- a/source/graphics/MapWriter.cpp
+++ b/source/graphics/MapWriter.cpp
@@ -265,7 +265,7 @@ void CMapWriter::WriteXML(const VfsPath& filename,
 			CVector3D in = pCamera->m_Orientation.GetIn();
 			// Convert to spherical coordinates
 			float rotation = atan2(in.X, in.Z);
-			float declination = atan2(sqrt(in.X*in.X + in.Z*in.Z), in.Y) - M_PI/2;
+			float declination = atan2(sqrt(in.X*in.X + in.Z*in.Z), in.Y) - (float)M_PI/2;
 
 			{
 				XML_Element("Rotation");
diff --git a/source/lib/res/graphics/ogl_tex.cpp b/source/lib/res/graphics/ogl_tex.cpp
index da358a6114..4b36912e9e 100644
--- a/source/lib/res/graphics/ogl_tex.cpp
+++ b/source/lib/res/graphics/ogl_tex.cpp
@@ -1017,5 +1017,5 @@ bool ogl_tex_has_s3tc()
 	// ogl_tex_upload must be called before this
 	debug_assert(have_s3tc != -1);
 
-	return have_s3tc;
+	return (have_s3tc != 0);
 }
diff --git a/source/maths/MathUtil.h b/source/maths/MathUtil.h
index f564807ea1..6696165dcd 100644
--- a/source/maths/MathUtil.h
+++ b/source/maths/MathUtil.h
@@ -18,8 +18,8 @@
 #ifndef INCLUDED_MATHUTIL
 #define INCLUDED_MATHUTIL
 
-#define DEGTORAD(a)					((a) * (M_PI/180.0f))
-#define RADTODEG(a)					((a) * (180.0f/M_PI))
+#define DEGTORAD(a)					((a) * ((float)M_PI/180.0f))
+#define RADTODEG(a)					((a) * (180.0f/(float)M_PI))
 #define SQR(x)						((x) * (x))
 
 template <typename T>
diff --git a/source/maths/Noise.cpp b/source/maths/Noise.cpp
index 2701508e77..d7cef05970 100644
--- a/source/maths/Noise.cpp
+++ b/source/maths/Noise.cpp
@@ -54,7 +54,7 @@ Noise2D::Noise2D(int f)
 		grads[i] = new CVector2D_Maths[freq];
 		for(int j=0; j<freq; j++) 
 		{
-			float a = randFloat() * 2 * M_PI;
+			float a = randFloat() * 2 * (float)M_PI;
 			grads[i][j] = CVector2D_Maths(cos(a), sin(a));
 		}
 	}
diff --git a/source/maths/Quaternion.cpp b/source/maths/Quaternion.cpp
index 2ddac488ec..78abb8b43c 100644
--- a/source/maths/Quaternion.cpp
+++ b/source/maths/Quaternion.cpp
@@ -132,13 +132,13 @@ CVector3D CQuaternion::ToEulerAngles()
 	if (test > (.5f-EPSILON)*unit) 
 	{ // singularity at north pole
 		heading = 2 * atan2( m_V.X, m_W);
-		attitude = M_PI/2;
+		attitude = (float)M_PI/2;
 		bank = 0;
 	}
 	else if (test < (-.5f+EPSILON)*unit) 
 	{ // singularity at south pole
 		heading = -2 * atan2(m_V.X, m_W);
-		attitude = -M_PI/2;
+		attitude = -(float)M_PI/2;
 		bank = 0;
 	}
 	else 
diff --git a/source/ps/Interact.cpp b/source/ps/Interact.cpp
index 3cf6f57dc9..a33e572d45 100644
--- a/source/ps/Interact.cpp
+++ b/source/ps/Interact.cpp
@@ -1371,7 +1371,7 @@ void ResetInteraction()
 	customSelectionMode = false;
 }
 
-static const float angleBias = 3*M_PI/4;	// Atlas does the same
+static const float angleBias = 3*(float)M_PI/4;	// Atlas does the same
 
 bool CBuildingPlacer::Activate(CStrW& templateName)
 {	
@@ -1480,7 +1480,7 @@ void CBuildingPlacer::Update( float timeStep )
 		if(x*x + z*z < 3*3)
 		{
 			if(m_dragged || m_timeSinceClick > 0.2f)
-				m_angle += timeStep * M_PI;
+				m_angle += timeStep * (float)M_PI;
 		}
 		else
 		{
@@ -1517,7 +1517,7 @@ void CBuildingPlacer::Update( float timeStep )
 
 	// Set position and angle to the location we decided on
 	CMatrix3D m;
-	m.SetYRotation(m_angle + M_PI);
+	m.SetYRotation(m_angle + (float)M_PI);
 	m.Translate(pos);
 	m_actor->GetModel()->SetTransform( m );
 	m_bounds->SetPosition(pos.X, pos.Z);
@@ -1540,7 +1540,7 @@ void CBuildingPlacer::Update( float timeStep )
 	}
 	else
 	{
-		float add = ( sin(4*M_PI*m_totalTime) + 1.0f ) * 0.08f;
+		float add = ( sin(4*(float)M_PI*m_totalTime) + 1.0f ) * 0.08f;
 		col = CColor( 1.4f+add, 0.4f+add, 0.4f+add, 1.0f );
 	}
 	m_actor->GetModel()->SetShadingColor( col );
diff --git a/source/simulation/BoundingObjects.cpp b/source/simulation/BoundingObjects.cpp
index d1a9b460c6..a4b586fdff 100644
--- a/source/simulation/BoundingObjects.cpp
+++ b/source/simulation/BoundingObjects.cpp
@@ -96,7 +96,7 @@ void CBoundingCircle::Render( float height )
 
 	for( int i = 0; i < 10; i++ )
 	{
-		float ang = i * 2 * M_PI / 10.0f;
+		float ang = i * 2 * (float)M_PI / 10.0f;
 		float x = m_pos.x + m_radius * sin( ang );
 		float y = m_pos.y + m_radius * cos( ang );
 		glVertex3f( x, height, y );
diff --git a/source/simulation/Entity.cpp b/source/simulation/Entity.cpp
index 910a83c384..c1b8fe1ae0 100644
--- a/source/simulation/Entity.cpp
+++ b/source/simulation/Entity.cpp
@@ -53,7 +53,7 @@
 
 #include "ps/GameSetup/Config.h"
 
-const float MAX_ROTATION_RATE = 2*M_PI; // radians per second
+const float MAX_ROTATION_RATE = 2*(float)M_PI; // radians per second
 
 CEntity::CEntity( CEntityTemplate* base, CVector3D position, float orientation, const std::set<CStr8>& actorSelections, const CStrW* building )
 {
@@ -235,7 +235,7 @@ void CEntity::initAuraData()
 
 		for ( int j=0; j<AURA_CIRCLE_POINTS; ++j )
 		{
-			float val = j * 2*M_PI / (float)AURA_CIRCLE_POINTS;
+			float val = j * 2*(float)M_PI / AURA_CIRCLE_POINTS;
 			m_unsnappedPoints[i][j] = CVector2D( cosf(val)*radius, 
 											sinf(val)*radius );
 		}
@@ -461,9 +461,9 @@ void CEntity::Update( int timestep )
 
 	float delta = m_orientation.Y - m_orientation_smoothed.Y;
 	// Wrap delta to -M_PI..M_PI
-	delta = fmod(delta + M_PI, 2*M_PI); // range -2PI..2PI
-	if (delta < 0) delta += 2*M_PI; // range 0..2PI
-	delta -= M_PI; // range -M_PI..M_PI
+	delta = fmod(delta + (float)M_PI, 2*(float)M_PI); // range -2PI..2PI
+	if (delta < 0) delta += 2*(float)M_PI; // range 0..2PI
+	delta -= (float)M_PI; // range -M_PI..M_PI
 	// Clamp to max rate
 	float deltaClamped = clamp(delta, -MAX_ROTATION_RATE*timestep/1000.f, +MAX_ROTATION_RATE*timestep/1000.f);
 	// Calculate new orientation, in a peculiar way in order to make sure the
@@ -1039,24 +1039,24 @@ void CEntity::Interpolate( float relativeoffset )
 
 	// Avoid wraparound glitches for interpolating angles.
 	
-	m_orientation.X = fmodf(m_orientation.X, 2*M_PI); // (ensure the following loops can't take forever)
-	m_orientation.Y = fmodf(m_orientation.Y, 2*M_PI);
-	m_orientation.Z = fmodf(m_orientation.Z, 2*M_PI);
+	m_orientation.X = fmodf(m_orientation.X, 2*(float)M_PI); // (ensure the following loops can't take forever)
+	m_orientation.Y = fmodf(m_orientation.Y, 2*(float)M_PI);
+	m_orientation.Z = fmodf(m_orientation.Z, 2*(float)M_PI);
 
-	while( m_orientation.Y < m_orientation_previous.Y - M_PI )
-		m_orientation_previous.Y -= 2 * M_PI;
-	while( m_orientation.Y > m_orientation_previous.Y + M_PI )
-		m_orientation_previous.Y += 2 * M_PI;
+	while( m_orientation.Y < m_orientation_previous.Y - (float)M_PI )
+		m_orientation_previous.Y -= 2 * (float)M_PI;
+	while( m_orientation.Y > m_orientation_previous.Y + (float)M_PI )
+		m_orientation_previous.Y += 2 * (float)M_PI;
 
-	while( m_orientation.X < m_orientation_previous.X - M_PI )
-		m_orientation_previous.X -= 2 * M_PI;
-	while( m_orientation.X > m_orientation_previous.X + M_PI )
-		m_orientation_previous.X += 2 * M_PI;
+	while( m_orientation.X < m_orientation_previous.X - (float)M_PI )
+		m_orientation_previous.X -= 2 * (float)M_PI;
+	while( m_orientation.X > m_orientation_previous.X + (float)M_PI )
+		m_orientation_previous.X += 2 * (float)M_PI;
 
-	while( m_orientation.Z < m_orientation_previous.Z - M_PI )
-		m_orientation_previous.Z -= 2 * M_PI;
-	while( m_orientation.Z > m_orientation_previous.Z + M_PI )
-		m_orientation_previous.Z += 2 * M_PI;
+	while( m_orientation.Z < m_orientation_previous.Z - (float)M_PI )
+		m_orientation_previous.Z -= 2 * (float)M_PI;
+	while( m_orientation.Z > m_orientation_previous.Z + (float)M_PI )
+		m_orientation_previous.Z += 2 * (float)M_PI;
 
 	UpdateXZOrientation();
 
diff --git a/source/simulation/EntityRendering.cpp b/source/simulation/EntityRendering.cpp
index b5412a1f8a..b3b670309d 100644
--- a/source/simulation/EntityRendering.cpp
+++ b/source/simulation/EntityRendering.cpp
@@ -162,7 +162,7 @@ void CEntity::RenderSelectionOutline( float alpha )
 			float radius = ((CBoundingCircle*)m_bounds)->m_radius;
 			for( int i = 0; i < SELECTION_CIRCLE_POINTS; i++ )
 			{
-				float ang = i * 2 * M_PI / (float)SELECTION_CIRCLE_POINTS;
+				float ang = i * 2 * (float)M_PI / SELECTION_CIRCLE_POINTS;
 				float x = pos.X + radius * sin( ang );
 				float y = pos.Z + radius * cos( ang );
 #ifdef SELECTION_TERRAIN_CONFORMANCE
diff --git a/source/simulation/EntityScriptInterface.cpp b/source/simulation/EntityScriptInterface.cpp
index 5349ddd256..508ef7fa2e 100644
--- a/source/simulation/EntityScriptInterface.cpp
+++ b/source/simulation/EntityScriptInterface.cpp
@@ -154,7 +154,7 @@ JSBool CEntity::Construct( JSContext* cx, JSObject* UNUSED(obj), uintN argc, jsv
 	debug_assert( argc >= 2 );
 
 	CVector3D position;
-	float orientation = g_Game->GetSimulation()->RandFloat() * 2 * M_PI;
+	float orientation = g_Game->GetSimulation()->RandFloat() * 2 * (float)M_PI;
 
 	JSObject* jsEntityTemplate = JSVAL_TO_OBJECT( argv[0] );
 	CStrW templateName;
@@ -502,10 +502,10 @@ jsval_t CEntity::GetSpawnPoint( JSContext* UNUSED(cx), uintN argc, jsval* argv )
 	else if( m_bounds->m_type == CBoundingObject::BOUND_CIRCLE )
 	{
 		float ang;
-		ang = g_Game->GetSimulation()->RandFloat() * 2 * M_PI;
+		ang = g_Game->GetSimulation()->RandFloat() * 2 * (float)M_PI;
 		float radius = m_bounds->m_radius + 1.0f + spawn_clearance;
 		float d_ang = spawn_clearance / ( 2.0f * radius );
-		float ang_end = ang + 2.0f * M_PI;
+		float ang_end = ang + 2.0f * (float)M_PI;
 		float x = 0.0f, y = 0.0f; // make sure they're initialized
 		for( ; ang < ang_end; ang += d_ang )
 		{
diff --git a/source/simulation/EntityStateProcessing.cpp b/source/simulation/EntityStateProcessing.cpp
index 63cf949671..7fa23f0322 100644
--- a/source/simulation/EntityStateProcessing.cpp
+++ b/source/simulation/EntityStateProcessing.cpp
@@ -84,7 +84,7 @@ float CEntity::ChooseMovementSpeed( float distance )
 
 	// Modify the speed based on the slope of the terrain in our direction (obtained from our x orientation)
 	float angle = m_orientation_unclamped.x;
-	int sector = rintf( angle / (M_PI/2) * m_base->m_pitchDivs );
+	int sector = rintf( angle / ((float)M_PI/2) * m_base->m_pitchDivs );
 	speed -= sector * m_base->m_pitchValue;
 
 	entf_set_to(ENTF_IS_RUNNING, should_run);
@@ -130,8 +130,8 @@ int CEntity::ProcessGotoHelper( CEntityOrder* current, int timestep_millis, HEnt
 
 	m_targetorientation = atan2( delta.x, delta.y );
 	float deltatheta = m_targetorientation - (float)m_orientation.Y;
-	while( deltatheta > M_PI ) deltatheta -= 2 * M_PI;
-	while( deltatheta < -M_PI ) deltatheta += 2 * M_PI;
+	while( deltatheta > (float)M_PI ) deltatheta -= 2 * (float)M_PI;
+	while( deltatheta < -(float)M_PI ) deltatheta += 2 * (float)M_PI;
 
 	if( fabs( deltatheta ) > 0.01f )
 	{
@@ -336,7 +336,7 @@ bool CEntity::ProcessGotoNoPathing( CEntityOrder* current, int timestep_millis )
 		{
 			delta = interval / r;
 			theta += delta;
-			r += ( interval * delta ) / ( 2 * M_PI );
+			r += ( interval * delta ) / ( 2 * (float)M_PI );
 			destinationObs.SetPosition( _x + r * cosf( theta ), _y + r * sinf( theta ) );
 			if( !GetCollisionObject( &destinationObs ) ) break;
 		}
diff --git a/source/simulation2/components/CCmpPosition.cpp b/source/simulation2/components/CCmpPosition.cpp
index 86974ddd55..233455a6e1 100644
--- a/source/simulation2/components/CCmpPosition.cpp
+++ b/source/simulation2/components/CCmpPosition.cpp
@@ -334,9 +334,9 @@ public:
 			float rotY = m_RotY.ToFloat();
 			float delta = rotY - m_InterpolatedRotY;
 			// Wrap delta to -M_PI..M_PI
-			delta = fmod(delta + M_PI, 2*M_PI); // range -2PI..2PI
-			if (delta < 0) delta += 2*M_PI; // range 0..2PI
-			delta -= M_PI; // range -M_PI..M_PI
+			delta = fmod(delta + (float)M_PI, 2*(float)M_PI); // range -2PI..2PI
+			if (delta < 0) delta += 2*(float)M_PI; // range 0..2PI
+			delta -= (float)M_PI; // range -M_PI..M_PI
 			// Clamp to max rate
 			float deltaClamped = clamp(delta, -m_RotYSpeed*msgData.frameTime, +m_RotYSpeed*msgData.frameTime);
 			// Calculate new orientation, in a peculiar way in order to make sure the
diff --git a/source/simulation2/helpers/Render.cpp b/source/simulation2/helpers/Render.cpp
index f00755a11c..275d7ee0ab 100644
--- a/source/simulation2/helpers/Render.cpp
+++ b/source/simulation2/helpers/Render.cpp
@@ -38,7 +38,7 @@ void SimRender::ConstructCircleOnGround(const CSimContext& context, float x, flo
 
 	for (size_t i = 0; i <= RENDER_CIRCLE_POINTS; ++i) // use '<=' so it's a closed loop
 	{
-		float a = i * 2 * M_PI / RENDER_CIRCLE_POINTS;
+		float a = i * 2 * (float)M_PI / RENDER_CIRCLE_POINTS;
 		float px = x + radius * sin(a);
 		float pz = z + radius * cos(a);
 		float py = cmpTerrain->GetGroundLevel(px, pz) + RENDER_HEIGHT_DELTA;
diff --git a/source/tools/atlas/GameInterface/ActorViewer.cpp b/source/tools/atlas/GameInterface/ActorViewer.cpp
index 5067424531..65b6997576 100644
--- a/source/tools/atlas/GameInterface/ActorViewer.cpp
+++ b/source/tools/atlas/GameInterface/ActorViewer.cpp
@@ -184,9 +184,9 @@ void ActorViewer::SetActor(const CStrW& name, const CStrW& animation)
 		if (! m.Unit)
 			return;
 
-		float angle = M_PI;
+		float angle = (float)M_PI;
 		CMatrix3D mat;
-		mat.SetYRotation(angle + M_PI);
+		mat.SetYRotation(angle + (float)M_PI);
 		mat.Translate(CELL_SIZE * PATCH_SIZE/2, 0.f, CELL_SIZE * PATCH_SIZE/2);
 		m.Unit->GetModel()->SetTransform(mat);
 		m.Unit->GetModel()->ValidatePosition();
diff --git a/source/tools/atlas/GameInterface/Handlers/EnvironmentHandlers.cpp b/source/tools/atlas/GameInterface/Handlers/EnvironmentHandlers.cpp
index c7d2a61b1a..38ab36b63a 100644
--- a/source/tools/atlas/GameInterface/Handlers/EnvironmentHandlers.cpp
+++ b/source/tools/atlas/GameInterface/Handlers/EnvironmentHandlers.cpp
@@ -50,8 +50,8 @@ sEnvironmentSettings GetSettings()
 #undef COLOUR
 
 	float sunrotation = g_LightEnv.GetRotation();
-	if (sunrotation > M_PI)
-		sunrotation -= M_PI*2;
+	if (sunrotation > (float)M_PI)
+		sunrotation -= (float)M_PI*2;
 	s.sunrotation = sunrotation;
 	s.sunelevation = g_LightEnv.GetElevation();
 
diff --git a/source/tools/atlas/GameInterface/SimState.cpp b/source/tools/atlas/GameInterface/SimState.cpp
index 85dccafaed..9e351b187b 100644
--- a/source/tools/atlas/GameInterface/SimState.cpp
+++ b/source/tools/atlas/GameInterface/SimState.cpp
@@ -85,7 +85,7 @@ CUnit* SimState::Nonentity::Thaw()
 	if (! unit)
 		return NULL;
 	CMatrix3D m;
-	m.SetYRotation(angle + M_PI);
+	m.SetYRotation(angle + (float)M_PI);
 	m.Translate(position);
 	unit->GetModel()->SetTransform(m);