vcl: Allow SalGraphics to draw gradients natively

The aim of this patch is to allow for native gradient rendering in
SalGraphics (i.e. let OpenGL do this natively). It is a two step
process:

1. I need to allow gradient draw into SalGraphics, however the current
completely intertwined with the metafile code in OutputDevice. I am
seperating the gradient metafile code from the gradient drawing code.

2. After splitting the metafile stuff from the actual gradient drawing,
I am now able to call on SalGraphics::DrawGradient(). This just
calls on SalGraphics::drawGradient() which returns false if there is
no way of drawing native gradients, and true if there is. If false,
then we use OutputDevice's DrawGradient() functionality.

Change-Id: Ibaaabe13b76a8e7a037d9f751b5f662653a50566
Reviewed-on: https://gerrit.libreoffice.org/12119
Reviewed-by: Chris Sherlock <chris.sherlock79@gmail.com>
Tested-by: Chris Sherlock <chris.sherlock79@gmail.com>

6 files changed, 18 insertions, 0 deletions

diff --git a/vcl/inc/generic/genpspgraphics.h b/vcl/inc/generic/genpspgraphics.h
index 2a562c341ff7..30c8fecd5eea 100644
--- a/vcl/inc/generic/genpspgraphics.h
+++ b/vcl/inc/generic/genpspgraphics.h
@@ -148,6 +148,8 @@ public:
                                                    const sal_uInt32* pPoints,
                                                    const SalPoint* const* pPtAry,
                                                    const sal_uInt8* const* pFlgAry ) SAL_OVERRIDE;
+    virtual bool            drawGradient( const tools::PolyPolygon&, const Gradient& ) SAL_OVERRIDE { return false; };
+
     virtual void            copyArea( long nDestX,
                                       long nDestY,
                                       long nSrcX,
diff --git a/vcl/inc/headless/svpgdi.hxx b/vcl/inc/headless/svpgdi.hxx
index a872d4a2019d..cbbac7a4b1dd 100644
--- a/vcl/inc/headless/svpgdi.hxx
+++ b/vcl/inc/headless/svpgdi.hxx
@@ -211,6 +211,7 @@ public:
                                                    const sal_uInt32* pPoints,
                                                    const SalPoint* const* pPtAry,
                                                    const sal_uInt8* const* pFlgAry ) SAL_OVERRIDE;
+    virtual bool            drawGradient( const tools::PolyPolygon&, const Gradient& ) SAL_OVERRIDE { return false; };
 
     virtual void            copyArea( long nDestX,
                                       long nDestY,
diff --git a/vcl/inc/quartz/salgdi.h b/vcl/inc/quartz/salgdi.h
index 23d3bb3904a9..eb21e09a6710 100644
--- a/vcl/inc/quartz/salgdi.h
+++ b/vcl/inc/quartz/salgdi.h
@@ -237,6 +237,7 @@ public:
                                 const ::basegfx::B2DVector& rLineWidths,
                                 basegfx::B2DLineJoin,
                                 com::sun::star::drawing::LineCap eLineCap) SAL_OVERRIDE;
+    virtual bool            drawGradient( const tools::PolyPolygon&, const Gradient& ) SAL_OVERRIDE { return false; };
 
     // CopyArea --> No RasterOp, but ClipRegion
     virtual void            copyArea( long nDestX, long nDestY, long nSrcX, long nSrcY, long nSrcWidth,
diff --git a/vcl/inc/salgdi.hxx b/vcl/inc/salgdi.hxx
index 7e06ee6d82e7..2266d87ee64e 100644
--- a/vcl/inc/salgdi.hxx
+++ b/vcl/inc/salgdi.hxx
@@ -288,6 +288,12 @@ public:
                                     const sal_uInt8* const* pFlgAry,
                                     const OutputDevice *pOutDev );
 
+    bool                        DrawGradient(
+                                    const tools::PolyPolygon& rPolyPoly,
+                                    const Gradient& rGradient,
+                                    OutputDevice* );
+
+
     // CopyArea --> No RasterOp, but ClipRegion
     void                        CopyArea(
                                     long nDestX, long nDestY,
@@ -451,6 +457,11 @@ protected:
                                     const SalPoint* const* pPtAry,
                                     const sal_uInt8* const* pFlgAry ) = 0;
 
+
+    virtual bool                drawGradient(
+                                    const tools::PolyPolygon& rPolyPoly,
+                                    const Gradient& rGradient ) = 0;
+
     // CopyArea --> No RasterOp, but ClipRegion
     virtual void                copyArea(
                                     long nDestX, long nDestY,
diff --git a/vcl/inc/unx/salgdi.h b/vcl/inc/unx/salgdi.h
index c4eea0fe3c37..f56411227405 100644
--- a/vcl/inc/unx/salgdi.h
+++ b/vcl/inc/unx/salgdi.h
@@ -277,6 +277,8 @@ public:
         basegfx::B2DLineJoin,
         com::sun::star::drawing::LineCap) SAL_OVERRIDE;
     virtual bool            drawFilledTrapezoids( const ::basegfx::B2DTrapezoid*, int nTrapCount, double fTransparency );
+    virtual bool            drawGradient( const tools::PolyPolygon&, const Gradient& ) SAL_OVERRIDE { return false; };
+
 
 #if 1 // TODO: remove these obselete methods
     virtual bool        drawPolyLineBezier( sal_uInt32 nPoints,
diff --git a/vcl/inc/win/salgdi.h b/vcl/inc/win/salgdi.h
index 66c561830e49..ca423fb46f8d 100644
--- a/vcl/inc/win/salgdi.h
+++ b/vcl/inc/win/salgdi.h
@@ -219,6 +219,7 @@ protected:
     virtual bool    drawPolyLineBezier( sal_uInt32 nPoints, const SalPoint* pPtAry, const sal_uInt8* pFlgAry );
     virtual bool    drawPolygonBezier( sal_uInt32 nPoints, const SalPoint* pPtAry, const sal_uInt8* pFlgAry );
     virtual bool    drawPolyPolygonBezier( sal_uInt32 nPoly, const sal_uInt32* pPoints, const SalPoint* const* pPtAry, const BYTE* const* pFlgAry );
+    virtual bool        drawGradient( const tools::PolyPolygon&, const Gradient& ) SAL_OVERRIDE { return false; };
 
     // CopyArea --> No RasterOp, but ClipRegion
     virtual void        copyArea( long nDestX, long nDestY, long nSrcX, long nSrcY, long nSrcWidth,