Merge branch 'dpi-textctrl' of https://github.com/MaartenBent/wxWidgets

Improvements for wxTextCtrl, wxSearchCtrl, wxButton when using
non-default DPI.

See https://github.com/wxWidgets/wxWidgets/pull/1634

include/wx/msw/private.h

@@ -91,12 +91,13 @@ WXDLLIMPEXP_BASE void wxSetInstance(HINSTANCE hInst);
 // Return the height of a native text control corresponding to the given
 // character height (as returned by GetCharHeight() or wxGetCharSize()).
 //
-// The wxWindow parameter must be valid and used for getting the DPI.
-inline int wxGetEditHeightFromCharHeight(int cy, const wxWindow* w)
+// The wxWindow parameter is currently not used but should still be valid.
+inline int wxGetEditHeightFromCharHeight(int cy, const wxWindow* WXUNUSED(w))
 {
     // The value 8 here is empiric, i.e. it's not necessarily correct, but
     // seems to work relatively well.
-    return cy + w->FromDIP(8);
+    // Don't use FromDIP(8), this seems not needed.
+    return cy + 8;
 }
 
 // Compatibility macro used in the existing code. It assumes that it's called

include/wx/msw/textctrl.h

@@ -244,6 +244,9 @@ protected:
 #if wxUSE_RICHEDIT
     virtual void MSWUpdateFontOnDPIChange(const wxSize& newDPI) wxOVERRIDE;
 
+    // Apply m_richDPIscale zoom to rich control.
+    void MSWSetRichZoom();
+
     // Apply the character-related parts of wxTextAttr to the given selection
     // or the entire control if start == end == -1.
     //
@@ -265,6 +268,10 @@ protected:
     // (although not directly: 1 is for 1.0, 2 is for either 2.0 or 3.0 as we
     // can't nor really need to distinguish between them and 4 is for 4.1)
     int m_verRichEdit;
+
+    // Rich text controls need temporary scaling when they are created on a
+    // display with non-system DPI.
+    float m_richDPIscale;
 #endif // wxUSE_RICHEDIT
 
     // number of EN_UPDATE events sent by Windows when we change the controls