remove 1 pixel white band in XRectPreview

Change-Id: I3089f9305b8142e2c78405a4f9ae6a2066e90cfa
Reviewed-on: https://gerrit.libreoffice.org/59725
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

include/svx/dlgctrl.hxx

@@ -478,6 +478,7 @@ class SAL_WARN_UNUSED SVX_DLLPUBLIC XRectPreview : public PreviewBase
 private:
     SdrObject* mpRectangleObject;
 
+    tools::Rectangle GetPreviewSize() const;
 public:
     XRectPreview();
     virtual void SetDrawingArea(weld::DrawingArea* pDrawingArea) override;

svx/source/dialog/dlgctrl.cxx

@@ -2270,27 +2270,36 @@ XRectPreview::XRectPreview()
 {
 }
 
+// expand to avoid 1 pixel band to the right and bottom of previews
+// in color/gradient/bitmap/pattern/hatch subpages of area tab
+// in e.g. page dialog
+tools::Rectangle XRectPreview::GetPreviewSize() const
+{
+    tools::Rectangle aObjectSize(Point(), GetOutputSizePixel());
+    aObjectSize.AdjustRight(1);
+    aObjectSize.AdjustBottom(1);
+    return aObjectSize;
+}
+
 void XRectPreview::SetDrawingArea(weld::DrawingArea* pDrawingArea)
 {
     PreviewBase::SetDrawingArea(pDrawingArea);
     InitSettings();
 
     // create RectangleObject
-    const tools::Rectangle aObjectSize(Point(), GetOutputSizePixel());
     mpRectangleObject = new SdrRectObj(
         getModel(),
-        aObjectSize);
+        GetPreviewSize());
 }
 
 void XRectPreview::Resize()
 {
-    const tools::Rectangle aObjectSize(Point(), GetOutputSizePixel());
     SdrObject *pOrigObject = mpRectangleObject;
     if (pOrigObject)
     {
         mpRectangleObject = new SdrRectObj(
             getModel(),
-            aObjectSize);
+            GetPreviewSize());
         SetAttributes(pOrigObject->GetMergedItemSet());
         SdrObject::Free(pOrigObject);
     }