fdo#74336 draw hairline if line width is small

RenderPolygonStrokePrimitive2D draws a simple hairline if the
line width is less than 1.0 (and less than 1.5 if no AA is used)
so in tryDrawPolygonStrokePrimitive2DDirect we need to reflect
this behaviour - otherwise the lines are drawn too small.

Change-Id: Icd3d8f35a00346b1d624b6df010f43ed21968d04

drawinglayer/source/processor2d/vclpixelprocessor2d.cxx

@@ -237,6 +237,16 @@ namespace drawinglayer
                 fLineWidth = aLineWidth.getLength();
             }
 
+            // draw simple hairline for small line widths
+            // see also RenderPolygonStrokePrimitive2D which is used if this try fails
+            bool bIsAntiAliasing = getOptionsDrawinglayer().IsAntiAliasing();
+            if (   (basegfx::fTools::lessOrEqual(fLineWidth, 1.0) && bIsAntiAliasing)
+                || (basegfx::fTools::lessOrEqual(fLineWidth, 1.5) && !bIsAntiAliasing))
+            {
+                // draw simple hairline
+                fLineWidth = 0.0;
+            }
+
             bool bHasPoints(false);
             bool bTryWorked(false);