From 55d033c68c7a406505cf22b2592ce43d2da2582e Mon Sep 17 00:00:00 2001
From: Vadim Zeitlin <vadim@wxwidgets.org>
Date: Fri, 25 Oct 2019 00:30:42 +0200
Subject: [PATCH] Scale the bitmap in place in wxAuiScaleBitmap()

This makes the function simpler and is slightly more efficient.

No real changes.
---
 src/aui/dockart.cpp | 15 +++++++++------
 src/aui/tabart.cpp  | 11 ++++++-----
 2 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/src/aui/dockart.cpp b/src/aui/dockart.cpp
index 7818b2b8aa..4ebf227714 100644
--- a/src/aui/dockart.cpp
+++ b/src/aui/dockart.cpp
@@ -89,21 +89,24 @@ wxBitmap wxAuiBitmapFromBits(const unsigned char bits[], int w, int h,
     return wxBitmap(img);
 }
 
-// wxAuiScaleBitmap is a utility function that scales a TabArt bitmap
-wxBitmap wxAuiScaleBitmap(const wxBitmap& bmp, double scale)
+// A utility function to scales a bitmap in place for use at the given scale
+// factor.
+void wxAuiScaleBitmap(wxBitmap& bmp, double scale)
 {
+#if wxUSE_IMAGE && !defined(__WXGTK3__) && !defined(__WXMAC__)
     // scale to a close round number to improve quality
     scale = floor(scale + 0.25);
-#if wxUSE_IMAGE && !defined(__WXGTK3__) && !defined(__WXMAC__)
     if (scale > 1.0 && !(bmp.GetScaleFactor() > 1.0))
     {
         wxImage img = bmp.ConvertToImage();
         img.Rescale(bmp.GetWidth()*scale, bmp.GetHeight()*scale,
             wxIMAGE_QUALITY_BOX_AVERAGE);
-        return wxBitmap(img);
+        bmp = wxBitmap(img);
     }
+#else
+    wxUnusedVar(bmp);
+    wxUnusedVar(scale);
 #endif // wxUSE_IMAGE
-    return bmp;
 }
 
 static void DrawGradientRectangle(wxDC& dc,
@@ -765,7 +768,7 @@ void wxAuiDefaultDockArt::DrawPaneButton(wxDC& dc,
             break;
     }
 
-    bmp = wxAuiScaleBitmap(bmp, window->GetContentScaleFactor());
+    wxAuiScaleBitmap(bmp, window->GetContentScaleFactor());
 
     wxRect rect = _rect;
 
diff --git a/src/aui/tabart.cpp b/src/aui/tabart.cpp
index efb641342c..60e7939a7e 100644
--- a/src/aui/tabart.cpp
+++ b/src/aui/tabart.cpp
@@ -72,7 +72,8 @@ private:
 wxBitmap wxAuiBitmapFromBits(const unsigned char bits[], int w, int h,
                              const wxColour& color);
 
-wxBitmap wxAuiScaleBitmap(const wxBitmap& bmp, double scale);
+// This function is defined in dockart.cpp.
+void wxAuiScaleBitmap(wxBitmap& bmp, double scale);
 
 wxString wxAuiChopText(wxDC& dc, const wxString& text, int max_size);
 
@@ -561,7 +562,7 @@ void wxAuiGenericTabArt::DrawTab(wxDC& dc,
             bmp = m_activeCloseBmp;
         }
 
-        bmp = wxAuiScaleBitmap(bmp, wnd->GetContentScaleFactor());
+        wxAuiScaleBitmap(bmp, wnd->GetContentScaleFactor());
 
         int offsetY = tab_y-1;
         if (m_flags & wxAUI_NB_BOTTOM)
@@ -743,7 +744,7 @@ void wxAuiGenericTabArt::DrawButton(wxDC& dc,
     if (!bmp.IsOk())
         return;
 
-    bmp = wxAuiScaleBitmap(bmp, wnd->GetContentScaleFactor());
+    wxAuiScaleBitmap(bmp, wnd->GetContentScaleFactor());
 
     rect = in_rect;
 
@@ -1110,7 +1111,7 @@ void wxAuiSimpleTabArt::DrawTab(wxDC& dc,
         else
             bmp = m_disabledCloseBmp;
 
-        bmp = wxAuiScaleBitmap(bmp, wnd->GetContentScaleFactor());
+        wxAuiScaleBitmap(bmp, wnd->GetContentScaleFactor());
 
         wxRect rect(tab_x + tab_width - bmp.GetScaledWidth() - 1,
                     tab_y + (tab_height/2) - (bmp.GetScaledHeight()/2) + 1,
@@ -1252,7 +1253,7 @@ void wxAuiSimpleTabArt::DrawButton(wxDC& dc,
     if (!bmp.IsOk())
         return;
 
-    bmp = wxAuiScaleBitmap(bmp, wnd->GetContentScaleFactor());
+    wxAuiScaleBitmap(bmp, wnd->GetContentScaleFactor());
 
     rect = in_rect;