Add support for gradient stops to wxGraphicsContext.

Allow specifying a set of gradient stops instead of just the beginning and
ending colours. Add the new wxGraphicsGradientStop(s) classes and new
wxGraphicsContext::Create{Linear,Radial}GradientBrush() overloads. Also change
the same methods of wxGraphicsRenderer to take wxGraphicsGradientStops instead
of a pair of colours.

Implement the new API for MSW and Cairo. OS X still uses just the two colours
for now.

Closes #11897.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@63857 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

docs/changes.txt

@@ -499,6 +499,7 @@ All (GUI):
 - Add "initial selection" parameter to wxGetSingleChoice() (Nikolay Tjushkov).
 - Implement wxDocument::Revert() (troelsk).
 - Allow overriding print preview frame creation in docview (troelsk).
+- Added support for gradient stops in wxGraphicsContext (Kit Bishop).
 - Added wxTransparentColour.
 
 GTK:

include/wx/graphics.h

@@ -19,6 +19,7 @@
 #include "wx/geometry.h"
 #include "wx/dynarray.h"
 #include "wx/dc.h"
+#include "wx/vector.h"
 
 enum wxAntialiasMode
 {
@@ -304,6 +305,81 @@ private:
 extern WXDLLIMPEXP_DATA_CORE(wxGraphicsPath) wxNullGraphicsPath;
 
 
+// Describes a single gradient stop.
+class wxGraphicsGradientStop
+{
+public:
+    wxGraphicsGradientStop(wxColour col, float pos)
+        : m_col(col),
+          m_pos(pos)
+    {
+    }
+
+    // default copy ctor, assignment operator and dtor are ok
+
+    const wxColour& GetColour() const { return m_col; }
+    void SetColour(const wxColour& col) { m_col = col; }
+
+    float GetPosition() const { return m_pos; }
+    void SetPosition(float pos)
+    {
+        wxASSERT_MSG( pos >= 0 && pos < 1, "invalid gradient stop position" );
+
+        m_pos = pos;
+    }
+
+private:
+    // The colour of this gradient band.
+    wxColour m_col;
+
+    // Its starting position: 0 is the beginning and 1 is the end.
+    float m_pos;
+};
+
+// A collection of gradient stops ordered by their positions (from lowest to
+// highest). The first stop (index 0, position 0.0) is always the starting
+// colour and the last one (index GetCount() - 1, position 1.0) is the end
+// colour.
+class WXDLLIMPEXP_CORE wxGraphicsGradientStops
+{
+public:
+    wxGraphicsGradientStops(wxColour startCol = wxTransparentColour,
+                            wxColour endCol = wxTransparentColour)
+    {
+        // we can't use Add() here as it relies on having start/end stops as
+        // first/last array elements so do it manually
+        m_stops.push_back(wxGraphicsGradientStop(startCol, 0.));
+        m_stops.push_back(wxGraphicsGradientStop(endCol, 1.));
+    }
+
+    // default copy ctor, assignment operator and dtor are ok for this class
+
+
+    // Add a stop in correct order.
+    void Add(const wxGraphicsGradientStop& stop);
+    void Add(wxColour col, float pos) { Add(wxGraphicsGradientStop(col, pos)); }
+
+    // Get the number of stops.
+    unsigned GetCount() const { return m_stops.size(); }
+
+    // Return the stop at the given index (which must be valid).
+    wxGraphicsGradientStop Item(unsigned n) const { return m_stops.at(n); }
+
+    // Get/set start and end colours.
+    void SetStartColour(wxColour col)
+        { m_stops[0].SetColour(col); }
+    wxColour GetStartColour() const
+        { return m_stops[0].GetColour(); }
+    void SetEndColour(wxColour col)
+        { m_stops[m_stops.size() - 1].SetColour(col); }
+    wxColour GetEndColour() const
+        { return m_stops[m_stops.size() - 1].GetColour(); }
+
+private:
+    // All the stops stored in ascending order of positions.
+    wxVector<wxGraphicsGradientStop> m_stops;
+};
+
 class WXDLLIMPEXP_CORE wxGraphicsContext : public wxGraphicsObject
 {
 public:
@@ -348,14 +424,29 @@ public:
 
     virtual wxGraphicsBrush CreateBrush(const wxBrush& brush ) const;
 
-    // sets the brush to a linear gradient, starting at (x1,y1) with color c1 to (x2,y2) with color c2
-    virtual wxGraphicsBrush CreateLinearGradientBrush( wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2,
-        const wxColour&c1, const wxColour&c2) const;
+    // sets the brush to a linear gradient, starting at (x1,y1) and ending at
+    // (x2,y2) with the given boundary colours or the specified stops
+    wxGraphicsBrush
+    CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                              wxDouble x2, wxDouble y2,
+                              const wxColour& c1, const wxColour& c2) const;
+    wxGraphicsBrush
+    CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                              wxDouble x2, wxDouble y2,
+                              const wxGraphicsGradientStops& stops) const;
 
-    // sets the brush to a radial gradient originating at (xo,yc) with color oColor and ends on a circle around (xc,yc)
-    // with radius r and color cColor
-    virtual wxGraphicsBrush CreateRadialGradientBrush( wxDouble xo, wxDouble yo, wxDouble xc, wxDouble yc, wxDouble radius,
-        const wxColour &oColor, const wxColour &cColor) const;
+    // sets the brush to a radial gradient originating at (xo,yc) and ending
+    // on a circle around (xc,yc) with the given radius; the colours may be
+    // specified by just the two extremes or the full array of gradient stops
+    wxGraphicsBrush
+    CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                              wxDouble xc, wxDouble yc, wxDouble radius,
+                              const wxColour& oColor, const wxColour& cColor) const;
+
+    wxGraphicsBrush
+    CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                              wxDouble xc, wxDouble yc, wxDouble radius,
+                              const wxGraphicsGradientStops& stops) const;
 
     // sets the font
     virtual wxGraphicsFont CreateFont( const wxFont &font , const wxColour &col = *wxBLACK ) const;
@@ -644,16 +735,21 @@ public:
 
     virtual wxGraphicsBrush CreateBrush(const wxBrush& brush ) = 0;
 
-    // sets the brush to a linear gradient, starting at (x1,y1) with color c1 to (x2,y2) with color c2
-    virtual wxGraphicsBrush CreateLinearGradientBrush( wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2,
-        const wxColour&c1, const wxColour&c2) = 0;
+    // Gradient brush creation functions may not honour all the stops specified
+    // stops and use just its boundary colours (this is currently the case
+    // under OS X)
+    virtual wxGraphicsBrush
+    CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                              wxDouble x2, wxDouble y2,
+                              const wxGraphicsGradientStops& stops) = 0;
 
-    // sets the brush to a radial gradient originating at (xo,yc) with color oColor and ends on a circle around (xc,yc)
-    // with radius r and color cColor
-    virtual wxGraphicsBrush CreateRadialGradientBrush( wxDouble xo, wxDouble yo, wxDouble xc, wxDouble yc, wxDouble radius,
-        const wxColour &oColor, const wxColour &cColor) = 0;
+    virtual wxGraphicsBrush
+    CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                              wxDouble xc, wxDouble yc,
+                              wxDouble radius,
+                              const wxGraphicsGradientStops& stops) = 0;
 
-   // sets the font
+    // sets the font
     virtual wxGraphicsFont CreateFont( const wxFont &font , const wxColour &col = *wxBLACK ) = 0;
 
     // create a native bitmap representation

interface/wx/graphics.h

@@ -361,15 +361,25 @@ public:
     static wxGraphicsContext* CreateFromNativeWindow(void* window);
 
     /**
-        Creates a native brush, having a linear gradient, starting at
-        (@a x1, @a y1) with color @a c1 to (@a x2, @a y2) with color @a c2.
+        Creates a native brush with a linear gradient.
+
+        The brush starts at (@a x1, @a y1) and ends at (@a x2, @a y2). Either
+        just the start and end gradient colours (@a c1 and @a c2) or full set
+        of gradient @a stops can be specified.
+
+        The version taking wxGraphicsGradientStops is new in wxWidgets 2.9.1.
     */
-    virtual wxGraphicsBrush CreateLinearGradientBrush(wxDouble x1,
-                                                      wxDouble y1,
-                                                      wxDouble x2,
-                                                      wxDouble y2,
-                                                      const wxColour& c1,
-                                                      const wxColour& c2) const;
+    //@{
+    wxGraphicsBrush
+    CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                              wxDouble x2, wxDouble y2,
+                              const wxColour& c1, const wxColour& c2) const;
+
+    wxGraphicsBrush
+    CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                              wxDouble x2, wxDouble y2,
+                              const wxGraphicsGradientStops& stops) const;
+    //@}
 
     /**
         Creates a native affine transformation matrix from the passed in
@@ -391,15 +401,30 @@ public:
     virtual wxGraphicsPen CreatePen(const wxPen& pen) const;
 
     /**
-        Creates a native brush, having a radial gradient originating at
-        (@a xo, @a yc) with color @a oColour and ends on a circle around
-        (@a xc, @a yc) with the given @a radius and color @a cColour.
+        Creates a native brush with a radial gradient.
+
+        The brush originats at (@a xo, @a yc) and ends on a circle around
+        (@a xc, @a yc) with the given @a radius.
+
+        The gradient may be specified either by its start and end colours @a
+        oColor and @a cColor or by a full set of gradient @a stops.
+
+        The version taking wxGraphicsGradientStops is new in wxWidgets 2.9.1.
     */
-    virtual wxGraphicsBrush CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
-                                                      wxDouble xc, wxDouble yc,
-                                                      wxDouble radius,
-                                                      const wxColour& oColor,
-                                                      const wxColour& cColor) const;
+    //@{
+    virtual wxGraphicsBrush
+    CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                              wxDouble xc, wxDouble yc,
+                              wxDouble radius,
+                              const wxColour& oColor,
+                              const wxColour& cColor) const;
+
+    virtual wxGraphicsBrush
+    CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                              wxDouble xc, wxDouble yc,
+                              wxDouble radius,
+                              const wxGraphicsGradientStops& stops) = 0;
+    //@}
 
     /**
         Draws the bitmap. In case of a mono bitmap, this is treated as a mask
@@ -643,7 +668,120 @@ public:
 
 };
 
+/**
+    Represents a single gradient stop in a collection of gradient stops as
+    represented by wxGraphicsGradientStops.
 
+    @library{wxcore}
+    @category{gdi}
+
+    @since 2.9.1
+*/
+class wxGraphicsGradientStop
+{
+public:
+    /**
+        Creates a stop with the given colour and position.
+
+        @param col The colour of this stop. Note that the alpha component of
+            the colour is honoured thus allowing the background colours to
+            partially show through the gradient.
+        @param pos The stop position, must be in [0, 1) range with 0 being the
+            beginning and 1 the end of the gradient (but it doesn't make sense
+            to create a stop at position 1 because it would never be visible
+            anyhow).
+    */
+    wxGraphicsGradientStop(wxColour col, float pos);
+
+    /// Return the stop colour.
+    const wxColour& GetColour() const;
+
+    /**
+        Change the stop colour.
+
+        @param col The new colour.
+    */
+    void SetColour(const wxColour& col);
+
+    /// Return the stop position.
+    float GetPosition() const;
+
+    /**
+        Change the stop position.
+
+        @param pos The new position, must always be in [0, 1) range.
+    */
+    void SetPosition(float pos);
+};
+
+/**
+    Represents a collection of wxGraphicGradientStop values for use with
+    CreateLinearGradientBrush and CreateRadialGradientBrush.
+
+    The stops are maintained in order of position.  If two or more stops are
+    added with the same position then the one(s) added later come later.
+    This can be useful for producing discontinuities in the colour gradient.
+
+    Notice that this class is write-once, you can't modify the stops once they
+    had been added.
+
+    @library{wxcore}
+    @category{gdi}
+
+    @since 2.9.1
+*/
+class wxGraphicsGradientStops
+{
+public:
+    /**
+        Initializes the gradient stops with the given boundary colours.
+
+        Creates a wxGraphicsGradientStops instance with start colour given
+        by @a startCol and end colour given by @a endCol.
+    */
+    wxGraphicsGradientStops(wxColour startCol = wxTransparentColour,
+                            wxColour endCol = wxTransparentColour);
+
+    /**
+        Add a new stop.
+    */
+    //@{
+    void Add(const wxGraphicsGradientStop& stop);
+    void Add(wxColour col, float pos);
+    //@}
+
+    /**
+        Returns the stop at the given index.
+
+        @param n The index, must be in [0, GetCount()) range.
+    */
+    wxGraphicsGradientStop Item(unsigned n) const;
+
+    /**
+        Returns the number of stops.
+    */
+    unsigned GetCount() const;
+
+    /**
+        Set the start colour to @a col
+    */
+    void SetStartColour(wxColour col);
+
+    /**
+        Returns the start colour.
+    */
+    wxColour GetStartColour() const;
+
+    /**
+        Set the end colour to @a col
+    */
+    void SetEndColour(wxColour col);
+
+    /**
+        Returns the end colour.
+    */
+    wxColour GetEndColour() const;
+};
 
 /**
     @class wxGraphicsRenderer
@@ -718,16 +856,18 @@ public:
     virtual wxGraphicsFont CreateFont(const wxFont& font,
                                       const wxColour& col = *wxBLACK) = 0;
 
+
     /**
-        Creates a native brush, having a linear gradient, starting at
-        (@a x1, @a y1) with color @a c1 to (@a x2, @a y2) with color @a c2.
+        Creates a native brush with a linear gradient.
+
+        Stops support is new since wxWidgets 2.9.1, previously only the start
+        and end colours could be specified.
     */
     virtual wxGraphicsBrush CreateLinearGradientBrush(wxDouble x1,
                                                       wxDouble y1,
                                                       wxDouble x2,
                                                       wxDouble y2,
-                                                      const wxColour& c1,
-                                                      const wxColour& c2) = 0;
+                                                      const wxGraphicsGradientStops& stops) = 0;
 
     /**
         Creates a native affine transformation matrix from the passed in
@@ -749,15 +889,15 @@ public:
     virtual wxGraphicsPen CreatePen(const wxPen& pen) = 0;
 
     /**
-        Creates a native brush, having a radial gradient originating at
-        (@a xo, @a yc) with color @a oColour and ends on a circle around
-        (@a xc, @a yc) with the given @a radius and color @a cColour.
+        Creates a native brush with a radial gradient.
+
+        Stops support is new since wxWidgets 2.9.1, previously only the start
+        and end colours could be specified.
     */
     virtual wxGraphicsBrush CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
                                                       wxDouble xc, wxDouble yc,
                                                       wxDouble radius,
-                                                      const wxColour& oColour,
-                                                      const wxColour& cColour) = 0;
+                                                      const wxGraphicsGradientStops& stops) = 0;
 
     /**
         Returns the default renderer on this platform. On OS X this is the Core

samples/drawing/drawing.cpp

@@ -1231,6 +1231,7 @@ void MyCanvas::DrawGradients(wxDC& dc)
     r.Offset(0, TEXT_HEIGHT);
     dc.GradientFillLinear(r, *wxWHITE, *wxBLUE, wxUP);
 
+    wxRect  gfr = wxRect(r);
 
     // RHS: concentric
     r = wxRect(200, 10, 50, 50);
@@ -1283,6 +1284,127 @@ void MyCanvas::DrawGradients(wxDC& dc)
     dc.DrawRectangle(r4);
     r4.Deflate(1);
     dc.GradientFillLinear(r4, wxColour(0,0,0), wxColour(0,255,0), wxWEST);
+
+#if wxUSE_GRAPHICS_CONTEXT
+    if (m_useContext)
+    {
+        wxGCDC                      &gdc = (wxGCDC&)dc;
+        wxGraphicsContext           *gc = gdc.GetGraphicsContext();
+        wxGraphicsPath              pth;
+        wxGraphicsGradientStops     stops;
+
+        gfr.Offset(0, gfr.height + 10);
+        dc.DrawText(wxT("Linear Gradient with Stops"), gfr.x, gfr.y);
+        gfr.Offset(0, TEXT_HEIGHT);
+
+        stops = wxGraphicsGradientStops(wxColour(255,0,0), wxColour(0,0,255));
+        stops.Add(wxColour(255,255,0), 0.33f);
+        stops.Add(wxColour(0,255,0), 0.67f);
+
+        gc->SetBrush(gc->CreateLinearGradientBrush(gfr.x, gfr.y,
+                                                   gfr.x + gfr.width, gfr.y + gfr.height,
+                                                   stops));
+        pth = gc->CreatePath();
+        pth.MoveToPoint(gfr.x,gfr.y);
+        pth.AddLineToPoint(gfr.x + gfr.width,gfr.y);
+        pth.AddLineToPoint(gfr.x + gfr.width,gfr.y+gfr.height);
+        pth.AddLineToPoint(gfr.x,gfr.y+gfr.height);
+        pth.CloseSubpath();
+        gc->FillPath(pth);
+
+        gfr.Offset(0, gfr.height + 10);
+        dc.DrawText(wxT("Radial Gradient with Stops"), gfr.x, gfr.y);
+        gfr.Offset(0, TEXT_HEIGHT);
+
+        gc->SetBrush(gc->CreateRadialGradientBrush(gfr.x + gfr.width / 2,
+                                                   gfr.y + gfr.height / 2,
+                                                   gfr.x + gfr.width / 2,
+                                                   gfr.y + gfr.height / 2,
+                                                   gfr.width / 2,
+                                                   stops));
+        pth = gc->CreatePath();
+        pth.MoveToPoint(gfr.x,gfr.y);
+        pth.AddLineToPoint(gfr.x + gfr.width,gfr.y);
+        pth.AddLineToPoint(gfr.x + gfr.width,gfr.y+gfr.height);
+        pth.AddLineToPoint(gfr.x,gfr.y+gfr.height);
+        pth.CloseSubpath();
+        gc->FillPath(pth);
+
+        gfr.Offset(0, gfr.height + 10);
+        dc.DrawText(wxT("Linear Gradient with Stops and Gaps"), gfr.x, gfr.y);
+        gfr.Offset(0, TEXT_HEIGHT);
+
+        stops = wxGraphicsGradientStops(wxColour(255,0,0), wxColour(0,0,255));
+        stops.Add(wxColour(255,255,0), 0.33f);
+        stops.Add(wxTransparentColour, 0.33f);
+        stops.Add(wxTransparentColour, 0.67f);
+        stops.Add(wxColour(0,255,0), 0.67f);
+
+        gc->SetBrush(gc->CreateLinearGradientBrush(gfr.x, gfr.y + gfr.height,
+                                                   gfr.x + gfr.width, gfr.y,
+                                                   stops));
+        pth = gc->CreatePath();
+        pth.MoveToPoint(gfr.x,gfr.y);
+        pth.AddLineToPoint(gfr.x + gfr.width,gfr.y);
+        pth.AddLineToPoint(gfr.x + gfr.width,gfr.y+gfr.height);
+        pth.AddLineToPoint(gfr.x,gfr.y+gfr.height);
+        pth.CloseSubpath();
+        gc->FillPath(pth);
+
+        gfr.Offset(0, gfr.height + 10);
+        dc.DrawText(wxT("Radial Gradient with Stops and Gaps"), gfr.x, gfr.y);
+        gfr.Offset(0, TEXT_HEIGHT);
+
+        gc->SetBrush(gc->CreateRadialGradientBrush(gfr.x + gfr.width / 2,
+                                                   gfr.y + gfr.height / 2,
+                                                   gfr.x + gfr.width / 2,
+                                                   gfr.y + gfr.height / 2,
+                                                   gfr.width / 2,
+                                                   stops));
+        pth = gc->CreatePath();
+        pth.MoveToPoint(gfr.x,gfr.y);
+        pth.AddLineToPoint(gfr.x + gfr.width,gfr.y);
+        pth.AddLineToPoint(gfr.x + gfr.width,gfr.y+gfr.height);
+        pth.AddLineToPoint(gfr.x,gfr.y+gfr.height);
+        pth.CloseSubpath();
+        gc->FillPath(pth);
+
+        gfr.Offset(0, gfr.height + 10);
+        dc.DrawText(wxT("Gradients with Stops and Transparency"), gfr.x, gfr.y);
+        gfr.Offset(0, TEXT_HEIGHT);
+
+        stops = wxGraphicsGradientStops(wxColour(255,0,0), wxTransparentColour);
+        stops.Add(wxColour(255,0,0), 0.33f);
+        stops.Add(wxTransparentColour, 0.33f);
+        stops.Add(wxTransparentColour, 0.67f);
+        stops.Add(wxColour(0,0,255), 0.67f);
+        stops.Add(wxColour(0,0,255), 1.0f);
+
+        pth = gc->CreatePath();
+        pth.MoveToPoint(gfr.x,gfr.y);
+        pth.AddLineToPoint(gfr.x + gfr.width,gfr.y);
+        pth.AddLineToPoint(gfr.x + gfr.width,gfr.y+gfr.height);
+        pth.AddLineToPoint(gfr.x,gfr.y+gfr.height);
+        pth.CloseSubpath();
+
+        gc->SetBrush(gc->CreateRadialGradientBrush(gfr.x + gfr.width / 2,
+                                                   gfr.y + gfr.height / 2,
+                                                   gfr.x + gfr.width / 2,
+                                                   gfr.y + gfr.height / 2,
+                                                   gfr.width / 2,
+                                                   stops));
+        gc->FillPath(pth);
+
+        stops = wxGraphicsGradientStops(wxColour(255,0,0, 128), wxColour(0,0,255, 128));
+        stops.Add(wxColour(255,255,0,128), 0.33f);
+        stops.Add(wxColour(0,255,0,128), 0.67f);
+
+        gc->SetBrush(gc->CreateLinearGradientBrush(gfr.x, gfr.y,
+                                                   gfr.x + gfr.width, gfr.y,
+                                                   stops));
+        gc->FillPath(pth);
+    }
+#endif // wxUSE_GRAPHICS_CONTEXT
 }
 
 void MyCanvas::DrawRegions(wxDC& dc)
@@ -1504,8 +1626,8 @@ void MyCanvas::OnMouseMove(wxMouseEvent &event)
 
 void MyCanvas::OnMouseDown(wxMouseEvent &event)
 {
-	int x,y,xx,yy ;
-	event.GetPosition(&x,&y);
+    int x,y,xx,yy ;
+    event.GetPosition(&x,&y);
     CalcUnscrolledPosition( x, y, &xx, &yy );
     m_anchorpoint = wxPoint( xx , yy ) ;
     m_currentpoint = m_anchorpoint ;
@@ -1658,8 +1780,8 @@ MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size)
     m_xAxisReversed =
     m_yAxisReversed = false;
     m_backgroundMode = wxSOLID;
-    m_colourForeground = *wxRED;
-    m_colourBackground = *wxBLUE;
+    m_colourForeground = *wxBLACK;
+    m_colourBackground = *wxLIGHT_GREY;
     m_textureBackground = false;
 
     m_canvas = new MyCanvas( this );

src/common/graphcmn.cpp

@@ -489,6 +489,41 @@ void wxGraphicsPathData::AddArcToPoint( wxDouble x1, wxDouble y1 , wxDouble x2,
     AddLineToPoint(p2.m_x,p2.m_y);
 }
 
+//-----------------------------------------------------------------------------
+// wxGraphicsGradientStops
+//-----------------------------------------------------------------------------
+
+void wxGraphicsGradientStops::Add(const wxGraphicsGradientStop& stop)
+{
+    for ( wxVector<wxGraphicsGradientStop>::iterator it = m_stops.begin();
+          it != m_stops.end();
+          ++it )
+    {
+        if ( stop.GetPosition() < it->GetPosition() )
+        {
+            if ( it != m_stops.begin() )
+            {
+                m_stops.insert(it, stop);
+            }
+            else // we shouldn't be inserting it at the beginning
+            {
+                wxFAIL_MSG( "invalid gradient stop position < 0" );
+            }
+
+            return;
+        }
+    }
+
+    if ( stop.GetPosition() == 1. )
+    {
+        m_stops.insert(m_stops.end() - 1, stop);
+    }
+    else
+    {
+        wxFAIL_MSG( "invalid gradient stop position >= 1" );
+    }
+}
+
 //-----------------------------------------------------------------------------
 // wxGraphicsContext Convenience Methods
 //-----------------------------------------------------------------------------
@@ -753,19 +788,55 @@ wxGraphicsBrush wxGraphicsContext::CreateBrush(const wxBrush& brush ) const
     return GetRenderer()->CreateBrush(brush);
 }
 
-// sets the brush to a linear gradient, starting at (x1,y1) with color c1 to (x2,y2) with color c2
-wxGraphicsBrush wxGraphicsContext::CreateLinearGradientBrush( wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2,
-                                                   const wxColour&c1, const wxColour&c2) const
+wxGraphicsBrush
+wxGraphicsContext::CreateLinearGradientBrush(
+    wxDouble x1, wxDouble y1,
+    wxDouble x2, wxDouble y2,
+    const wxColour& c1, const wxColour& c2) const
 {
-    return GetRenderer()->CreateLinearGradientBrush(x1,y1,x2,y2,c1,c2);
+    return GetRenderer()->CreateLinearGradientBrush
+                          (
+                            x1, y1,
+                            x2, y2,
+                            wxGraphicsGradientStops(c1,c2)
+                          );
 }
 
-// sets the brush to a radial gradient originating at (xo,yc) with color oColor and ends on a circle around (xc,yc)
-// with radius r and color cColor
-wxGraphicsBrush wxGraphicsContext::CreateRadialGradientBrush( wxDouble xo, wxDouble yo, wxDouble xc, wxDouble yc, wxDouble radius,
-                                                   const wxColour &oColor, const wxColour &cColor) const
+wxGraphicsBrush
+wxGraphicsContext::CreateLinearGradientBrush(
+    wxDouble x1, wxDouble y1,
+    wxDouble x2, wxDouble y2,
+    const wxGraphicsGradientStops& gradientStops) const
 {
-    return GetRenderer()->CreateRadialGradientBrush(xo,yo,xc,yc,radius,oColor,cColor);
+    return GetRenderer()->CreateLinearGradientBrush(x1,y1,x2,y2, gradientStops);
+}
+
+wxGraphicsBrush
+wxGraphicsContext::CreateRadialGradientBrush(
+        wxDouble xo, wxDouble yo,
+        wxDouble xc, wxDouble yc, wxDouble radius,
+        const wxColour &oColor, const wxColour &cColor) const
+{
+    return GetRenderer()->CreateRadialGradientBrush
+                          (
+                            xo, yo,
+                            xc, yc, radius,
+                            wxGraphicsGradientStops(oColor, cColor)
+                          );
+}
+
+wxGraphicsBrush
+wxGraphicsContext::CreateRadialGradientBrush(
+        wxDouble xo, wxDouble yo,
+        wxDouble xc, wxDouble yc, wxDouble radius,
+        const wxGraphicsGradientStops& gradientStops) const
+{
+    return GetRenderer()->CreateRadialGradientBrush
+                          (
+                            xo, yo,
+                            xc, yc, radius,
+                            gradientStops
+                          );
 }
 
 // sets the font

src/generic/graphicc.cpp

@@ -248,14 +248,20 @@ public:
     ~wxCairoBrushData ();
 
     virtual void Apply( wxGraphicsContext* context );
-    void CreateLinearGradientBrush( wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2,
-        const wxColour&c1, const wxColour&c2 );
-    void CreateRadialGradientBrush( wxDouble xo, wxDouble yo, wxDouble xc, wxDouble yc, wxDouble radius,
-        const wxColour &oColor, const wxColour &cColor );
+
+    void CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                                   wxDouble x2, wxDouble y2,
+                                   const wxGraphicsGradientStops& stops);
+    void CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                                   wxDouble xc, wxDouble yc, wxDouble radius,
+                                   const wxGraphicsGradientStops& stops);
 
 protected:
     virtual void Init();
 
+    // common part of Create{Linear,Radial}GradientBrush()
+    void AddGradientStops(const wxGraphicsGradientStops& stops);
+
 private :
     double m_red;
     double m_green;
@@ -683,26 +689,50 @@ void wxCairoBrushData::Apply( wxGraphicsContext* context )
     }
 }
 
-void wxCairoBrushData::CreateLinearGradientBrush( wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2,
-        const wxColour&c1, const wxColour&c2 )
+void wxCairoBrushData::AddGradientStops(const wxGraphicsGradientStops& stops)
 {
-    m_brushPattern = cairo_pattern_create_linear(x1,y1,x2,y2);
-    cairo_pattern_add_color_stop_rgba(m_brushPattern,0.0,c1.Red()/255.0,
-        c1.Green()/255.0, c1.Blue()/255.0,c1.Alpha()/255.0);
-    cairo_pattern_add_color_stop_rgba(m_brushPattern,1.0,c2.Red()/255.0,
-        c2.Green()/255.0, c2.Blue()/255.0,c2.Alpha()/255.0);
-    wxASSERT_MSG(cairo_pattern_status(m_brushPattern) == CAIRO_STATUS_SUCCESS, wxT("Couldn't create cairo pattern"));
+    // loop over all the stops, they include the beginning and ending ones
+    const unsigned numStops = stops.GetCount();
+    for ( unsigned n = 0; n < numStops; n++ )
+    {
+        const wxGraphicsGradientStop stop = stops.Item(n);
+
+        const wxColour col = stop.GetColour();
+
+        cairo_pattern_add_color_stop_rgba
+        (
+            m_brushPattern,
+            stop.GetPosition(),
+            col.Red()/255.0,
+            col.Green()/255.0,
+            col.Blue()/255.0,
+            col.Alpha()/255.0
+        );
+    }
+
+    wxASSERT_MSG(cairo_pattern_status(m_brushPattern) == CAIRO_STATUS_SUCCESS,
+                 wxT("Couldn't create cairo pattern"));
 }
 
-void wxCairoBrushData::CreateRadialGradientBrush( wxDouble xo, wxDouble yo, wxDouble xc, wxDouble yc, wxDouble radius,
-        const wxColour &oColor, const wxColour &cColor )
+void
+wxCairoBrushData::CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                                            wxDouble x2, wxDouble y2,
+                                            const wxGraphicsGradientStops& stops)
+{
+    m_brushPattern = cairo_pattern_create_linear(x1,y1,x2,y2);
+
+    AddGradientStops(stops);
+}
+
+void
+wxCairoBrushData::CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                                            wxDouble xc, wxDouble yc,
+                                            wxDouble radius,
+                                            const wxGraphicsGradientStops& stops)
 {
     m_brushPattern = cairo_pattern_create_radial(xo,yo,0.0,xc,yc,radius);
-    cairo_pattern_add_color_stop_rgba(m_brushPattern,0.0,oColor.Red()/255.0,
-        oColor.Green()/255.0, oColor.Blue()/255.0,oColor.Alpha()/255.0);
-    cairo_pattern_add_color_stop_rgba(m_brushPattern,1.0,cColor.Red()/255.0,
-        cColor.Green()/255.0, cColor.Blue()/255.0,cColor.Alpha()/255.0);
-    wxASSERT_MSG(cairo_pattern_status(m_brushPattern) == CAIRO_STATUS_SUCCESS, wxT("Couldn't create cairo pattern"));
+
+    AddGradientStops(stops);
 }
 
 void wxCairoBrushData::Init()
@@ -1735,14 +1765,16 @@ public :
 
     virtual wxGraphicsBrush CreateBrush(const wxBrush& brush ) ;
 
-    // sets the brush to a linear gradient, starting at (x1,y1) with color c1 to (x2,y2) with color c2
-    virtual wxGraphicsBrush CreateLinearGradientBrush( wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2,
-        const wxColour&c1, const wxColour&c2) ;
+    virtual wxGraphicsBrush
+    CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                              wxDouble x2, wxDouble y2,
+                              const wxGraphicsGradientStops& stops);
 
-    // sets the brush to a radial gradient originating at (xo,yc) with color oColor and ends on a circle around (xc,yc)
-    // with radius r and color cColor
-    virtual wxGraphicsBrush CreateRadialGradientBrush( wxDouble xo, wxDouble yo, wxDouble xc, wxDouble yc, wxDouble radius,
-        const wxColour &oColor, const wxColour &cColor) ;
+    virtual wxGraphicsBrush
+    CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                              wxDouble xc, wxDouble yc,
+                              wxDouble radius,
+                              const wxGraphicsGradientStops& stops);
 
     // sets the font
     virtual wxGraphicsFont CreateFont( const wxFont &font , const wxColour &col = *wxBLACK ) ;
@@ -1874,25 +1906,26 @@ wxGraphicsBrush wxCairoRenderer::CreateBrush(const wxBrush& brush )
     }
 }
 
-// sets the brush to a linear gradient, starting at (x1,y1) with color c1 to (x2,y2) with color c2
-wxGraphicsBrush wxCairoRenderer::CreateLinearGradientBrush( wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2,
-                                                                      const wxColour&c1, const wxColour&c2)
+wxGraphicsBrush
+wxCairoRenderer::CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                                           wxDouble x2, wxDouble y2,
+                                           const wxGraphicsGradientStops& stops)
 {
     wxGraphicsBrush p;
     wxCairoBrushData* d = new wxCairoBrushData( this );
-    d->CreateLinearGradientBrush(x1, y1, x2, y2, c1, c2);
+    d->CreateLinearGradientBrush(x1, y1, x2, y2, stops);
     p.SetRefData(d);
     return p;
 }
 
-// sets the brush to a radial gradient originating at (xo,yc) with color oColor and ends on a circle around (xc,yc)
-// with radius r and color cColor
-wxGraphicsBrush wxCairoRenderer::CreateRadialGradientBrush( wxDouble xo, wxDouble yo, wxDouble xc, wxDouble yc, wxDouble radius,
-                                                                      const wxColour &oColor, const wxColour &cColor)
+wxGraphicsBrush
+wxCairoRenderer::CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                                           wxDouble xc, wxDouble yc, wxDouble r,
+                                           const wxGraphicsGradientStops& stops)
 {
     wxGraphicsBrush p;
     wxCairoBrushData* d = new wxCairoBrushData( this );
-    d->CreateRadialGradientBrush(xo,yo,xc,yc,radius,oColor,cColor);
+    d->CreateRadialGradientBrush(xo, yo, xc, yc, r, stops);
     p.SetRefData(d);
     return p;
 }

src/msw/graphics.cpp

@@ -246,16 +246,24 @@ public:
     wxGDIPlusBrushData( wxGraphicsRenderer* renderer, const wxBrush &brush );
     ~wxGDIPlusBrushData ();
 
-    void CreateLinearGradientBrush( wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2,
-        const wxColour&c1, const wxColour&c2 );
-    void CreateRadialGradientBrush( wxDouble xo, wxDouble yo, wxDouble xc, wxDouble yc, wxDouble radius,
-        const wxColour &oColor, const wxColour &cColor );
+    void CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                                   wxDouble x2, wxDouble y2,
+                                   const wxGraphicsGradientStops& stops);
+    void CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                                   wxDouble xc, wxDouble yc,
+                                   wxDouble radius,
+                                   const wxGraphicsGradientStops& stops);
+
     virtual Brush* GetGDIPlusBrush() { return m_brush; }
 
 protected:
     virtual void Init();
 
-private :
+private:
+    // common part of Create{Linear,Radial}GradientBrush()
+    template <typename T>
+    void SetGradientStops(T *brush, const wxGraphicsGradientStops& stops);
+
     Brush* m_brush;
     Image* m_brushImage;
     GraphicsPath* m_brushPath;
@@ -628,28 +636,67 @@ void wxGDIPlusBrushData::Init()
     m_brushPath= NULL;
 }
 
-void wxGDIPlusBrushData::CreateLinearGradientBrush( wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2, const wxColour&c1, const wxColour&c2)
+template <typename T>
+void
+wxGDIPlusBrushData::SetGradientStops(T *brush,
+        const wxGraphicsGradientStops& stops)
 {
-    m_brush = new LinearGradientBrush( PointF( x1,y1) , PointF( x2,y2),
-        Color( c1.Alpha(), c1.Red(),c1.Green() , c1.Blue() ),
-        Color( c2.Alpha(), c2.Red(),c2.Green() , c2.Blue() ));
+    const unsigned numStops = stops.GetCount();
+    if ( numStops <= 2 )
+    {
+        // initial and final colours are set during the brush creation, nothing
+        // more to do
+        return;
+    }
+
+    wxVector<Color> colors(numStops);
+    wxVector<REAL> positions(numStops);
+
+    for ( unsigned i = 0; i < numStops; i++ )
+    {
+        wxGraphicsGradientStop stop = stops.Item(i);
+
+        colors[i] = wxColourToColor(stop.GetColour());
+        positions[i] = stop.GetPosition();
+    }
+
+    brush->SetInterpolationColors(&colors[0], &positions[0], numStops);
 }
 
-void wxGDIPlusBrushData::CreateRadialGradientBrush( wxDouble xo, wxDouble yo, wxDouble xc, wxDouble yc, wxDouble radius,
-                                               const wxColour &oColor, const wxColour &cColor)
+void
+wxGDIPlusBrushData::CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                                              wxDouble x2, wxDouble y2,
+                                              const wxGraphicsGradientStops& stops)
+{
+    LinearGradientBrush * const
+        brush = new LinearGradientBrush(PointF(x1, y1) , PointF(x2, y2),
+                                        wxColourToColor(stops.GetStartColour()),
+                                        wxColourToColor(stops.GetEndColour()));
+    m_brush =  brush;
+
+    SetGradientStops(brush, stops);
+}
+
+void
+wxGDIPlusBrushData::CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                                              wxDouble xc, wxDouble yc,
+                                              wxDouble radius,
+                                              const wxGraphicsGradientStops& stops)
 {
-    // Create a path that consists of a single circle.
     m_brushPath = new GraphicsPath();
-    m_brushPath->AddEllipse( (REAL)(xc-radius), (REAL)(yc-radius), (REAL)(2*radius), (REAL)(2*radius));
+    m_brushPath->AddEllipse( (REAL)(xc-radius), (REAL)(yc-radius),
+                             (REAL)(2*radius), (REAL)(2*radius));
 
-    PathGradientBrush *b = new PathGradientBrush(m_brushPath);
-    m_brush = b;
-    b->SetCenterPoint( PointF(xo,yo));
-    b->SetCenterColor(Color( oColor.Alpha(), oColor.Red(),oColor.Green() , oColor.Blue() ));
+    PathGradientBrush * const brush = new PathGradientBrush(m_brushPath);
+    m_brush = brush;
+    brush->SetCenterPoint(PointF(xo, yo));
+    brush->SetCenterColor(wxColourToColor(stops.GetStartColour()));
 
-    Color colors[] = {Color( cColor.Alpha(), cColor.Red(),cColor.Green() , cColor.Blue() )};
+    const Color col(wxColourToColor(stops.GetEndColour()));
     int count = 1;
-    b->SetSurroundColors(colors, &count);
+    brush->SetSurroundColors(&col, &count);
+
+    SetGradientStops(brush, stops);
 }
 
 //-----------------------------------------------------------------------------
@@ -1596,15 +1643,16 @@ public :
 
     virtual wxGraphicsBrush CreateBrush(const wxBrush& brush ) ;
 
-    // sets the brush to a linear gradient, starting at (x1,y1) with color c1 to (x2,y2) with color c2
-    virtual wxGraphicsBrush CreateLinearGradientBrush( wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2,
-        const wxColour&c1, const wxColour&c2) ;
-
-    // sets the brush to a radial gradient originating at (xo,yc) with color oColor and ends on a circle around (xc,yc)
-    // with radius r and color cColor
-    virtual wxGraphicsBrush CreateRadialGradientBrush( wxDouble xo, wxDouble yo, wxDouble xc, wxDouble yc, wxDouble radius,
-        const wxColour &oColor, const wxColour &cColor) ;
+    virtual wxGraphicsBrush
+    CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                              wxDouble x2, wxDouble y2,
+                              const wxGraphicsGradientStops& stops);
 
+    virtual wxGraphicsBrush
+    CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                              wxDouble xc, wxDouble yc,
+                              wxDouble radius,
+                              const wxGraphicsGradientStops& stops);
     // sets the font
     virtual wxGraphicsFont CreateFont( const wxFont &font , const wxColour &col = *wxBLACK ) ;
 
@@ -1789,27 +1837,29 @@ wxGraphicsBrush wxGDIPlusRenderer::CreateBrush(const wxBrush& brush )
     }
 }
 
-// sets the brush to a linear gradient, starting at (x1,y1) with color c1 to (x2,y2) with color c2
-wxGraphicsBrush wxGDIPlusRenderer::CreateLinearGradientBrush( wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2,
-                                                                      const wxColour&c1, const wxColour&c2)
+wxGraphicsBrush
+wxGDIPlusRenderer::CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                                             wxDouble x2, wxDouble y2,
+                                             const wxGraphicsGradientStops& stops)
 {
     ENSURE_LOADED_OR_RETURN(wxNullGraphicsBrush);
     wxGraphicsBrush p;
     wxGDIPlusBrushData* d = new wxGDIPlusBrushData( this );
-    d->CreateLinearGradientBrush(x1, y1, x2, y2, c1, c2);
+    d->CreateLinearGradientBrush(x1, y1, x2, y2, stops);
     p.SetRefData(d);
     return p;
  }
 
-// sets the brush to a radial gradient originating at (xo,yc) with color oColor and ends on a circle around (xc,yc)
-// with radius r and color cColor
-wxGraphicsBrush wxGDIPlusRenderer::CreateRadialGradientBrush( wxDouble xo, wxDouble yo, wxDouble xc, wxDouble yc, wxDouble radius,
-                                                                      const wxColour &oColor, const wxColour &cColor)
+wxGraphicsBrush
+wxGDIPlusRenderer::CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                                             wxDouble xc, wxDouble yc,
+                                             wxDouble radius,
+                                             const wxGraphicsGradientStops& stops)
 {
     ENSURE_LOADED_OR_RETURN(wxNullGraphicsBrush);
     wxGraphicsBrush p;
     wxGDIPlusBrushData* d = new wxGDIPlusBrushData( this );
-    d->CreateRadialGradientBrush(xo,yo,xc,yc,radius,oColor,cColor);
+    d->CreateRadialGradientBrush(xo,yo,xc,yc,radius,stops);
     p.SetRefData(d);
     return p;
 }

src/osx/carbon/graphics.cpp

@@ -666,15 +666,18 @@ public:
     ~wxMacCoreGraphicsBrushData ();
 
     virtual void Apply( wxGraphicsContext* context );
-    void CreateLinearGradientBrush( wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2,
-        const wxColour&c1, const wxColour&c2 );
-    void CreateRadialGradientBrush( wxDouble xo, wxDouble yo, wxDouble xc, wxDouble yc, wxDouble radius,
-    const wxColour &oColor, const wxColour &cColor );
+    void CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                                   wxDouble x2, wxDouble y2,
+                                   const wxGraphicsGradientStops& stops);
+    void CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                                   wxDouble xc, wxDouble yc, wxDouble radius,
+                                   const wxGraphicsGradientStops& stops);
 
     virtual bool IsShading() { return m_isShading; }
     CGShadingRef GetShading() { return m_shading; }
 protected:
-    CGFunctionRef CreateGradientFunction( const wxColour& c1, const wxColour& c2 );
+    CGFunctionRef CreateGradientFunction(const wxGraphicsGradientStops& stops);
+
     static void CalculateShadingValues (void *info, const CGFloat *in, CGFloat *out);
     virtual void Init();
 
@@ -691,19 +694,24 @@ wxMacCoreGraphicsBrushData::wxMacCoreGraphicsBrushData( wxGraphicsRenderer* rend
     Init();
 }
 
-void wxMacCoreGraphicsBrushData::CreateLinearGradientBrush( wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2,
-        const wxColour&c1, const wxColour&c2 )
+void
+wxMacCoreGraphicsBrushData::CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                                                      wxDouble x2, wxDouble y2,
+                                                      const wxGraphicsGradientStops& stops)
 {
-    m_gradientFunction = CreateGradientFunction( c1, c2 );
+    m_gradientFunction = CreateGradientFunction(stops);
     m_shading = CGShadingCreateAxial( wxMacGetGenericRGBColorSpace(), CGPointMake((CGFloat) x1, (CGFloat) y1),
                                         CGPointMake((CGFloat) x2,(CGFloat) y2), m_gradientFunction, true, true ) ;
     m_isShading = true ;
 }
 
-void wxMacCoreGraphicsBrushData::CreateRadialGradientBrush( wxDouble xo, wxDouble yo, wxDouble xc, wxDouble yc, wxDouble radius,
-    const wxColour &oColor, const wxColour &cColor )
+void
+wxMacCoreGraphicsBrushData::CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                                                      wxDouble xc, wxDouble yc,
+                                                      wxDouble radius,
+                                                      const wxGraphicsGradientStops& stops)
 {
-    m_gradientFunction = CreateGradientFunction( oColor, cColor );
+    m_gradientFunction = CreateGradientFunction(stops);
     m_shading = CGShadingCreateRadial( wxMacGetGenericRGBColorSpace(), CGPointMake((CGFloat) xo,(CGFloat) yo), 0,
                                         CGPointMake((CGFloat) xc,(CGFloat) yc), (CGFloat) radius, m_gradientFunction, true, true ) ;
     m_isShading = true ;
@@ -759,8 +767,13 @@ void wxMacCoreGraphicsBrushData::CalculateShadingValues (void *info, const CGFlo
     }
 }
 
-CGFunctionRef wxMacCoreGraphicsBrushData::CreateGradientFunction( const wxColour& c1, const wxColour& c2 )
+CGFunctionRef
+wxMacCoreGraphicsBrushData::CreateGradientFunction(const wxGraphicsGradientStops& stops)
 {
+    // TODO: implement support for intermediate gradient stops
+    const wxColour c1 = stops.GetStartColour();
+    const wxColour c2 = stops.GetEndColour();
+
     static const CGFunctionCallbacks callbacks = { 0, &CalculateShadingValues, NULL };
     static const CGFloat input_value_range [2] = { 0, 1 };
     static const CGFloat output_value_ranges [8] = { 0, 1, 0, 1, 0, 1, 0, 1 };
@@ -2618,14 +2631,16 @@ public :
 
     virtual wxGraphicsBrush CreateBrush(const wxBrush& brush ) ;
 
-    // sets the brush to a linear gradient, starting at (x1,y1) with color c1 to (x2,y2) with color c2
-    virtual wxGraphicsBrush CreateLinearGradientBrush( wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2,
-        const wxColour&c1, const wxColour&c2) ;
+    virtual wxGraphicsBrush
+    CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                              wxDouble x2, wxDouble y2,
+                              const wxGraphicsGradientStops& stops);
 
-    // sets the brush to a radial gradient originating at (xo,yc) with color oColor and ends on a circle around (xc,yc)
-    // with radius r and color cColor
-    virtual wxGraphicsBrush CreateRadialGradientBrush( wxDouble xo, wxDouble yo, wxDouble xc, wxDouble yc, wxDouble radius,
-        const wxColour &oColor, const wxColour &cColor) ;
+    virtual wxGraphicsBrush
+    CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                              wxDouble xc, wxDouble yc,
+                              wxDouble radius,
+                              const wxGraphicsGradientStops& stops);
 
    // sets the font
     virtual wxGraphicsFont CreateFont( const wxFont &font , const wxColour &col = *wxBLACK ) ;
@@ -2819,25 +2834,27 @@ wxGraphicsBitmap wxMacCoreGraphicsRenderer::CreateSubBitmap( const wxGraphicsBit
         return wxNullGraphicsBitmap;
 }
 
-// sets the brush to a linear gradient, starting at (x1,y1) with color c1 to (x2,y2) with color c2
-wxGraphicsBrush wxMacCoreGraphicsRenderer::CreateLinearGradientBrush( wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2,
-    const wxColour&c1, const wxColour&c2)
+wxGraphicsBrush
+wxMacCoreGraphicsRenderer::CreateLinearGradientBrush(wxDouble x1, wxDouble y1,
+                                                     wxDouble x2, wxDouble y2,
+                                                     const wxGraphicsGradientStops& stops)
 {
     wxGraphicsBrush p;
     wxMacCoreGraphicsBrushData* d = new wxMacCoreGraphicsBrushData( this );
-    d->CreateLinearGradientBrush(x1, y1, x2, y2, c1, c2);
+    d->CreateLinearGradientBrush(x1, y1, x2, y2, stops);
     p.SetRefData(d);
     return p;
 }
 
-// sets the brush to a radial gradient originating at (xo,yc) with color oColor and ends on a circle around (xc,yc)
-// with radius r and color cColor
-wxGraphicsBrush wxMacCoreGraphicsRenderer::CreateRadialGradientBrush( wxDouble xo, wxDouble yo, wxDouble xc, wxDouble yc, wxDouble radius,
-    const wxColour &oColor, const wxColour &cColor)
+wxGraphicsBrush
+wxMacCoreGraphicsRenderer::CreateRadialGradientBrush(wxDouble xo, wxDouble yo,
+                                                     wxDouble xc, wxDouble yc,
+                                                     wxDouble radius,
+                                                     const wxGraphicsGradientStops& stops)
 {
     wxGraphicsBrush p;
     wxMacCoreGraphicsBrushData* d = new wxMacCoreGraphicsBrushData( this );
-    d->CreateRadialGradientBrush(xo,yo,xc,yc,radius,oColor,cColor);
+    d->CreateRadialGradientBrush(xo, yo, xc, yc, radius, stops);
     p.SetRefData(d);
     return p;
 }