Allow using wxRendererNative::DrawGauge() for vertical gauges too

It was unexpected that this method could only be used for horizontal
gauges, so make it work for the vertical ones if wxCONTROL_SPECIAL flag
is specified.

Update MSW and generic implementations and the render sample to show a
vertical gauge as well.

docs/changes.txt

@@ -180,6 +180,7 @@ All (GUI):
 - Add "hint" property to wxSearchCtrl XRC handler.
 - Add wxEVT_SEARCH[_CANCEL] synonyms for wxSearchCtrl events.
 - Generate wxEVT_SEARCH on Enter under all platforms.
+- Extend wxRendererNative::DrawGauge() to work for vertical gauges too.
 
 wxGTK:
 

include/wx/renderer.h

@@ -333,7 +333,9 @@ public:
                                     int flags = 0) = 0;
 #endif // wxHAS_DRAW_TITLE_BAR_BITMAP
 
-    // Draw a gauge with native style like a wxGauge would display
+    // Draw a gauge with native style like a wxGauge would display.
+    //
+    // wxCONTROL_SPECIAL flag must be used for drawing vertical gauges.
     virtual void DrawGauge(wxWindow* win,
                            wxDC& dc,
                            const wxRect& rect,

interface/wx/renderer.h

@@ -359,6 +359,8 @@ public:
         bar that is drawn as being filled in, @a max must be strictly positive
         and @a value must be between 0 and @a max.
 
+        @c wxCONTROL_SPECIAL must be set in @a flags for the vertical gauges.
+
         @since 3.1.0
      */
     virtual void DrawGauge(wxWindow* win,

samples/render/render.cpp

@@ -284,12 +284,17 @@ private:
         y += lineHeight + rBtn.height;
 #endif // wxHAS_DRAW_TITLE_BAR_BITMAP
 
+        // The meanings of those are reversed for the vertical gauge below.
         const wxCoord heightGauge = 24;
         const wxCoord widthGauge = 180;
 
         dc.DrawText("DrawGauge()", x1, y);
         renderer.DrawGauge(this, dc,
             wxRect(x2, y, widthGauge, heightGauge), 25, 100, m_flags);
+        renderer.DrawGauge(this, dc,
+            wxRect(x2 + widthGauge + 30, y + heightGauge - widthGauge,
+                   heightGauge, widthGauge),
+            25, 100, m_flags | wxCONTROL_SPECIAL);
 
         y += lineHeight + heightGauge;
 

src/generic/renderg.cpp

@@ -910,7 +910,7 @@ void wxRendererGeneric::DrawGauge(wxWindow* win,
                                   const wxRect& rect,
                                   int value,
                                   int max,
-                                  int WXUNUSED(flags))
+                                  int flags)
 {
     // Use same background as text controls.
     DrawTextCtrl(win, dc, rect);
@@ -918,7 +918,16 @@ void wxRendererGeneric::DrawGauge(wxWindow* win,
     // Calculate the progress bar size.
     wxRect progRect(rect);
     progRect.Deflate(2);
-    progRect.width = wxMulDivInt32(progRect.width, value, max);
+    if ( flags & wxCONTROL_SPECIAL )
+    {
+        const int h = wxMulDivInt32(progRect.height, value, max);
+        progRect.y += progRect.height - h;
+        progRect.height = h;
+    }
+    else // Horizontal.
+    {
+        progRect.width = wxMulDivInt32(progRect.width, value, max);
+    }
 
     dc.SetBrush(wxSystemSettings::GetColour(wxSYS_COLOUR_HIGHLIGHT));
     dc.SetPen(*wxTRANSPARENT_PEN);

src/msw/renderer.cpp

@@ -1098,7 +1098,7 @@ void wxRendererXP::DrawGauge(wxWindow* win,
     ::DrawThemeBackground(
         hTheme,
         GetHdcOf(dc.GetTempHDC()),
-        PP_BAR,
+        flags & wxCONTROL_SPECIAL ? PP_BARVERT : PP_BAR,
         0,
         &r,
         NULL);
@@ -1107,20 +1107,31 @@ void wxRendererXP::DrawGauge(wxWindow* win,
     ::GetThemeBackgroundContentRect(
         hTheme,
         GetHdcOf(dc.GetTempHDC()),
-        PP_BAR,
+        flags & wxCONTROL_SPECIAL ? PP_BARVERT : PP_BAR,
         0,
         &r,
         &contentRect);
 
-    contentRect.right = contentRect.left +
+    if ( flags & wxCONTROL_SPECIAL )
+    {
+        // For a vertical gauge, the value grows from the bottom to the top.
+        contentRect.top = contentRect.bottom -
+                          wxMulDivInt32(contentRect.bottom - contentRect.top,
+                                        value,
+                                        max);
+    }
+    else // Horizontal.
+    {
+        contentRect.right = contentRect.left +
                             wxMulDivInt32(contentRect.right - contentRect.left,
                                           value,
                                           max);
+    }
 
     ::DrawThemeBackground(
         hTheme,
         GetHdcOf(dc.GetTempHDC()),
-        PP_CHUNK,
+        flags & wxCONTROL_SPECIAL ? PP_CHUNKVERT : PP_CHUNK,
         0,
         &contentRect,
         NULL);