Fixed stroke semicircles drawing using shaderless OpenGL backend.

common/gal/opengl/opengl_gal.cpp

@@ -1024,15 +1024,11 @@ void OPENGL_GAL::drawStrokedSemiCircle( const VECTOR2D& aCenterPoint, double aRa
     else
     {
         // Compute the factors for the unit circle
-        double outerScale = lineWidth / aRadius / 2;
-        double innerScale = -outerScale;
-        outerScale += 1.0;
-        innerScale += 1.0;
+        double innerScale = 1.0 - lineWidth / aRadius;
 
-        if( innerScale < outerScale )
-        {
         Save();
         Translate( aCenterPoint );
+        Scale( VECTOR2D( aRadius, aRadius ) );
         Rotate( aAngle );
 
         // Draw the outline
@@ -1062,11 +1058,11 @@ void OPENGL_GAL::drawStrokedSemiCircle( const VECTOR2D& aCenterPoint, double aRa
             }
 
             vertex3( circle[i].x * innerScale,      circle[i].y * innerScale,       layerDepth );
-                vertex3( circle[i].x * outerScale, circle[i].y * outerScale, layerDepth );
+            vertex3( circle[i].x,                   circle[i].y,                    layerDepth );
             vertex3( circle[next].x * innerScale,   circle[next].y * innerScale,    layerDepth );
 
-                vertex3( circle[i].x * outerScale, circle[i].y * outerScale, layerDepth );
-                vertex3( circle[next].x * outerScale, circle[next].y * outerScale, layerDepth );
+            vertex3( circle[i].x,                   circle[i].y,                    layerDepth );
+            vertex3( circle[next].x,                circle[next].y,                 layerDepth );
             vertex3( circle[next].x * innerScale,   circle[next].y * innerScale,    layerDepth );
         }
 
@@ -1074,7 +1070,6 @@ void OPENGL_GAL::drawStrokedSemiCircle( const VECTOR2D& aCenterPoint, double aRa
 
         Restore();
     }
-    }
 }