diff --git a/dxfdata.cc b/dxfdata.cc
index 2a23f1f2..14c9c0e2 100644
--- a/dxfdata.cc
+++ b/dxfdata.cc
@@ -103,7 +103,7 @@ DxfData::DxfData(double fn, double fs, double fa, QString filename, QString laye
 				int n = get_fragments_from_r(radius, fn, fs, fa);
 				while (start_angle > stop_angle)
 					stop_angle += 360.0;
-				n = ceil(n * (stop_angle-start_angle) / 360);
+				n = (int)ceil(n * (stop_angle-start_angle) / 360);
 				for (int i = 0; i < n; i++) {
 					double a1 = ((stop_angle-start_angle)*i)/n;
 					double a2 = ((stop_angle-start_angle)*(i+1))/n;
diff --git a/dxflinextrude.cc b/dxflinextrude.cc
index ef54aa3c..4f2b0c4c 100644
--- a/dxflinextrude.cc
+++ b/dxflinextrude.cc
@@ -78,7 +78,7 @@ AbstractNode *DxfLinearExtrudeModule::evaluate(const Context *ctx, const ModuleI
 	node->filename = file.text;
 	node->layername = layer.text;
 	node->height = height.num;
-	node->convexity = convexity.num;
+	node->convexity = (int)convexity.num;
 	origin.getv2(node->origin_x, node->origin_y);
 	node->scale = scale.num;
 
@@ -97,9 +97,9 @@ AbstractNode *DxfLinearExtrudeModule::evaluate(const Context *ctx, const ModuleI
 	if (twist.type == Value::NUMBER) {
 		node->twist = twist.num;
 		if (slices.type == Value::NUMBER) {
-			node->slices = slices.num;
+			node->slices = (int)slices.num;
 		} else {
-			node->slices = fmax(2, fabs(get_fragments_from_r(node->height,
+			node->slices = (int)fmax(2, fabs(get_fragments_from_r(node->height,
 					node->fn, node->fs, node->fa) * node->twist / 360));
 		}
 		node->has_twist = true;
diff --git a/dxfrotextrude.cc b/dxfrotextrude.cc
index 7af70f30..e2aca988 100644
--- a/dxfrotextrude.cc
+++ b/dxfrotextrude.cc
@@ -71,7 +71,7 @@ AbstractNode *DxfRotateExtrudeModule::evaluate(const Context *ctx, const ModuleI
 
 	node->filename = file.text;
 	node->layername = layer.text;
-	node->convexity = convexity.num;
+	node->convexity = (int)convexity.num;
 	origin.getv2(node->origin_x, node->origin_y);
 	node->scale = scale.num;
 
diff --git a/dxftess.cc b/dxftess.cc
index 8aab35e6..ba62329e 100644
--- a/dxftess.cc
+++ b/dxftess.cc
@@ -228,7 +228,7 @@ void dxf_tesselate(PolySet *ps, DxfData *dxf, double rot, bool up, double h)
 	QHash<int, QPair_ii> tri_by_atan2;
 	for (int i = 0; i < tess_tri.count(); i++)
 	for (int j = 0; j < 3; j++) {
-		int ai = round(atan2(fabs(tess_tri[i].p[(j+1)%3][0] - tess_tri[i].p[j][0]),
+		int ai = (int)round(atan2(fabs(tess_tri[i].p[(j+1)%3][0] - tess_tri[i].p[j][0]),
 				fabs(tess_tri[i].p[(j+1)%3][1] - tess_tri[i].p[j][1])) / 0.001);
 		tri_by_atan2.insertMulti(ai, QPair<int,int>(i, j));
 	}
@@ -242,7 +242,7 @@ void dxf_tesselate(PolySet *ps, DxfData *dxf, double rot, bool up, double h)
 		for (int k = 0; k < 3; k++)
 		{
 			QHash<QPair_ii, QPair_ii> possible_neigh;
-			int ai = floor(atan2(fabs(tess_tri[i].p[(k+1)%3][0] - tess_tri[i].p[k][0]),
+			int ai = (int)floor(atan2(fabs(tess_tri[i].p[(k+1)%3][0] - tess_tri[i].p[k][0]),
 					fabs(tess_tri[i].p[(k+1)%3][1] - tess_tri[i].p[k][1])) / 0.001 - 0.5);
 			for (int j = 0; j < 2; j++) {
 				foreach (QPair_ii jl, tri_by_atan2.values(ai+j))
@@ -266,13 +266,13 @@ void dxf_tesselate(PolySet *ps, DxfData *dxf, double rot, bool up, double h)
 					tess_tri.append(tess_triangle(tess_tri[j].p[l],
 							tess_tri[i].p[(k+1)%3], tess_tri[i].p[(k+2)%3]));
 					for (int m = 0; m < 2; m++) {
-						int ai = round(atan2(fabs(tess_tri.last().p[(m+1)%3][0] - tess_tri.last().p[m][0]),
+						int ai = (int)round(atan2(fabs(tess_tri.last().p[(m+1)%3][0] - tess_tri.last().p[m][0]),
 								fabs(tess_tri.last().p[(m+1)%3][1] - tess_tri.last().p[m][1])) / 0.001 );
 						tri_by_atan2.insertMulti(ai, QPair<int,int>(tess_tri.count()-1, m));
 					}
 					tess_tri[i].p[(k+1)%3] = tess_tri[j].p[l];
 					for (int m = 0; m < 2; m++) {
-						int ai = round(atan2(fabs(tess_tri[i].p[(m+1)%3][0] - tess_tri[i].p[m][0]),
+						int ai = (int)round(atan2(fabs(tess_tri[i].p[(m+1)%3][0] - tess_tri[i].p[m][0]),
 								fabs(tess_tri[i].p[(m+1)%3][1] - tess_tri[i].p[m][1])) / 0.001 );
 						tri_by_atan2.insertMulti(ai, QPair<int,int>(i, m));
 					}
diff --git a/mainwin.cc b/mainwin.cc
index 2bfcf823..133fb5a9 100644
--- a/mainwin.cc
+++ b/mainwin.cc
@@ -228,7 +228,7 @@ void MainWindow::updatedFps()
 	if (!fps_ok || fps <= 0) {
 		animate_timer->stop();
 	} else {
-		animate_timer->setInterval(1000 / e_fps->text().toDouble());
+		animate_timer->setInterval(int(1000 / e_fps->text().toDouble()));
 		animate_timer->start();
 	}
 }
diff --git a/openscad.h b/openscad.h
index 716be372..e6add9cc 100644
--- a/openscad.h
+++ b/openscad.h
@@ -81,8 +81,8 @@ public:
 		res = resolution;
 	}
 	T &align(double &x, double &y) {
-		int ix = round(x / res);
-		int iy = round(y / res);
+		int ix = (int)round(x / res);
+		int iy = (int)round(y / res);
 		x = ix * res, y = iy * res;
 		if (db.contains(QPair<int,int>(ix, iy)))
 			return db[QPair<int,int>(ix, iy)];
@@ -103,14 +103,14 @@ public:
 		return db[QPair<int,int>(ix, iy)];
 	}
 	bool has(double x, double y) {
-		int ix = round(x / res);
-		int iy = round(y / res);
+		int ix = (int)round(x / res);
+		int iy = (int)round(y / res);
 		if (db.contains(QPair<int,int>(ix, iy)))
 			return true;
 		for (int jx = ix - 1; jx <= ix + 1; jx++)
 		for (int jy = iy - 1; jy <= iy + 1; jy++) {
 			if (db.contains(QPair<int,int>(jx, jy)))
-				true;
+				return true;
 		}
 		return false;
 	}
@@ -137,9 +137,9 @@ public:
 		res = resolution;
 	}
 	T &align(double &x, double &y, double &z) {
-		int ix = round(x / res);
-		int iy = round(y / res);
-		int iz = round(z / res);
+		int ix = (int)round(x / res);
+		int iy = (int)round(y / res);
+		int iz = (int)round(z / res);
 		x = ix * res, y = iy * res, z = iz * res;
 		if (db.contains(QPair<QPair<int,int>,int>(QPair<int,int>(ix, iy), iz)))
 			return db[QPair<QPair<int,int>,int>(QPair<int,int>(ix, iy), iz)];
@@ -162,9 +162,9 @@ public:
 		
 	}
 	bool has(double x, double y, double z) {
-		int ix = round(x / res);
-		int iy = round(y / res);
-		int iz = round(z / res);
+		int ix = (int)round(x / res);
+		int iy = (int)round(y / res);
+		int iz = (int)round(z / res);
 		if (db.contains(QPair<QPair<int,int>,int>(QPair<int,int>(ix, iy), iz)))
 			return true;
 		for (int jx = ix - 1; jx <= ix + 1; jx++)
diff --git a/primitives.cc b/primitives.cc
index c08e0a10..f93755c2 100644
--- a/primitives.cc
+++ b/primitives.cc
@@ -133,7 +133,7 @@ void register_builtin_primitives()
 int get_fragments_from_r(double r, double fn, double fs, double fa)
 {
 	if (fn > 0.0)
-		return fn;
+		return (int)fn;
 	return (int)ceil(fmax(fmin(360.0 / fa, r*M_PI / fs), 5));
 }
 
diff --git a/render.cc b/render.cc
index b9359a5c..98a8ecbc 100644
--- a/render.cc
+++ b/render.cc
@@ -56,7 +56,7 @@ AbstractNode *RenderModule::evaluate(const Context *ctx, const ModuleInstanciati
 
 	Value v = c.lookup_variable("convexity");
 	if (v.type == Value::NUMBER)
-		node->convexity = v.num;
+		node->convexity = (int)v.num;
 
 	foreach (ModuleInstanciation *v, inst->children) {
 		AbstractNode *n = v->evaluate(inst->ctx);
diff --git a/surface.cc b/surface.cc
index 17b859d3..5083c74b 100644
--- a/surface.cc
+++ b/surface.cc
@@ -63,7 +63,7 @@ AbstractNode *SurfaceModule::evaluate(const Context *ctx, const ModuleInstanciat
 
 	Value convexity = c.lookup_variable("convexity", true);
 	if (convexity.type == Value::NUMBER) {
-		node->convexity = convexity.num;
+		node->convexity = (int)convexity.num;
 	}
 
 	return node;