Avoid excessive text clipping on Windows

Use a better rounding strategy so that when the bounding box involves
part of a pixel we include the full pixel, so floor for -ve values and
ceil for +ve ones.  Without this I see lots of cut text on Windows.

Change-Id: I258f63eb37911574cd3f6f08da22349756c0775c

1 files changed, 4 insertions, 4 deletions

diff --git a/vcl/win/gdi/winlayout.cxx b/vcl/win/gdi/winlayout.cxx
index 50f6602db6ac..5655785345f7 100644
--- a/vcl/win/gdi/winlayout.cxx
+++ b/vcl/win/gdi/winlayout.cxx
@@ -3611,10 +3611,10 @@ std::vector<Rectangle> D2DWriteTextOutRenderer::GetGlyphInkBoxes(uint16_t * pGid
                    bottom = INT32(m.advanceHeight) - m.verticalOriginY - m.bottomSideBearing;
 
         // Scale to screen space.
-        pOut->Left()   = std::lround(left * mlfEmHeight / aFontMetrics.designUnitsPerEm);
-        pOut->Top()    = std::lround(top * mlfEmHeight / aFontMetrics.designUnitsPerEm);
-        pOut->Right()  = std::lround(right * mlfEmHeight / aFontMetrics.designUnitsPerEm);
-        pOut->Bottom() = std::lround(bottom * mlfEmHeight / aFontMetrics.designUnitsPerEm);
+        pOut->Left()   = std::floor(left * mlfEmHeight / aFontMetrics.designUnitsPerEm);
+        pOut->Top()    = std::floor(top * mlfEmHeight / aFontMetrics.designUnitsPerEm);
+        pOut->Right()  = std::ceil(right * mlfEmHeight / aFontMetrics.designUnitsPerEm);
+        pOut->Bottom() = std::ceil(bottom * mlfEmHeight / aFontMetrics.designUnitsPerEm);
 
         ++pOut;
     }