Added line height to wxRTC to allow faster scrolling if needed

include/wx/richtext/richtextctrl.h

@@ -2218,6 +2218,10 @@ public:
 
 #endif
 
+    /// Set the line increment height in pixels
+    void SetLineHeight(int height) { m_lineHeight = height; }
+    int GetLineHeight() const { return m_lineHeight; }
+
 // Implementation
 
     /**
@@ -2408,6 +2412,9 @@ protected:
     /// Whether images are enabled for this control
     bool                    m_enableImages;
 
+    /// Line height in pixels
+    int                     m_lineHeight;
+
     /// Whether delayed image loading is enabled for this control
     bool                    m_enableDelayedImageLoading;
     bool                    m_delayedImageProcessingRequired;

src/richtext/richtextctrl.cpp

@@ -389,6 +389,9 @@ void wxRichTextCtrl::Init()
     m_enableDelayedImageLoading = false;
     m_delayedImageProcessingRequired = false;
     m_delayedImageProcessingTime = 0;
+
+    // Line height in pixels
+    m_lineHeight = 5;
 }
 
 void wxRichTextCtrl::DoThaw()
@@ -2923,7 +2926,7 @@ void wxRichTextCtrl::SetupScrollbars(bool atTop, bool fromOnPaint)
 
     // TODO: reimplement scrolling so we scroll by line, not by fixed number
     // of pixels. See e.g. wxVScrolledWindow for ideas.
-    int pixelsPerUnit = 5;
+    int pixelsPerUnit = GetLineHeight();
     wxSize clientSize = GetClientSize();
 
     int maxHeight = (int) (0.5 + GetScale() * (GetBuffer().GetCachedSize().y + GetBuffer().GetTopMargin()));