Tweaked the Path2d::spiral to get rid of a wobble.

src/cinder/Path2d.cpp

@@ -689,15 +689,15 @@ Path2d Path2d::spiral( const vec2 &center, float innerRadius, float outerRadius,
 	Path2d shape;
 	shape.moveTo( center.x + p0.x * step, center.y + p0.y * step );
 
-	float radians = radiansStart + glm::radians( clamp( radiansStart * step, 3.0f, 90.0f ) ); // Adaptive step size.
+	float radians = radiansStart + glm::radians( clamp( radiansStart * step, 3.0f, 60.0f ) ); // Adaptive step size.
 	while( radians < radiansEnd ) {
 		const auto p3 = Point( radians, offset - radiansStart );
 		const auto controls = p3.generate( p0 );
 		shape.curveTo( center.x + controls.first.x * step, center.y + controls.first.y * step, center.x + controls.second.x * step, center.y + controls.second.y * step, center.x + p3.x * step, center.y + p3.y * step );
 
 		p0 = p3;
 
-		radians += glm::radians( glm::clamp( radians * step, 3.0f, 90.0f ) ); // Adaptive step size.
+		radians += glm::radians( glm::clamp( radians * step, 3.0f, 60.0f ) ); // Adaptive step size.
 	}
 
 	const auto p3 = Point( radiansEnd, offset - radiansStart );