diff --git a/extensions/fablabchemnitz/isometric_projection/dimetric_projection.inx b/extensions/fablabchemnitz/isometric_projection/dimetric_projection.inx
index 4c3497b..e179461 100644
--- a/extensions/fablabchemnitz/isometric_projection/dimetric_projection.inx
+++ b/extensions/fablabchemnitz/isometric_projection/dimetric_projection.inx
@@ -8,7 +8,7 @@
false
- 15.000
+ 15.000
all
diff --git a/extensions/fablabchemnitz/isometric_projection/isometric_projection.inx b/extensions/fablabchemnitz/isometric_projection/isometric_projection.inx
index e18b5f0..0a4338f 100644
--- a/extensions/fablabchemnitz/isometric_projection/isometric_projection.inx
+++ b/extensions/fablabchemnitz/isometric_projection/isometric_projection.inx
@@ -8,7 +8,7 @@
false
- 30.000
+ 30.000
all
diff --git a/extensions/fablabchemnitz/isometric_projection/isometric_projection.py b/extensions/fablabchemnitz/isometric_projection/isometric_projection.py
index f23a262..7d633e1 100644
--- a/extensions/fablabchemnitz/isometric_projection/isometric_projection.py
+++ b/extensions/fablabchemnitz/isometric_projection/isometric_projection.py
@@ -67,6 +67,9 @@ class IsometricProjection(inkex.EffectExtension):
self.arg_parser.add_argument('--orthoangle', type=float, default=15.0, help='Isometric angle in degrees')
def __initConstants(self, angle):
+ if angle == 0:
+ inkex.utils.debug("angle is set to 0°. This is not supported")
+ return
# Precomputed values for sine, cosine, and tangent of orthoangle.
self.rad = math.radians(angle)
self.cos = math.cos(self.rad)