tweak to return a cairo_context instead of a cairo_surface

Change-Id: Ifd5c9b1c2cc1561d9ca5dfd70ab7c3c74a1af216

vcl/inc/cairotextrender.hxx

@@ -79,7 +79,7 @@ class CairoTextRender : public TextRenderImpl
 
 protected:
     virtual GlyphCache&         getPlatformGlyphCache() = 0;
-    virtual cairo_surface_t*    getCairoSurface() = 0;
+    virtual cairo_t*            getCairoContext() = 0;
     virtual void                getSurfaceOffset(double& nDX, double& nDY) = 0;
     virtual void                drawSurface(cairo_t* cr) = 0;
 

vcl/unx/generic/gdi/cairotextrender.cxx

@@ -199,20 +199,18 @@ void CairoTextRender::DrawServerFontLayout( const ServerFontLayout& rLayout )
     if (cairo_glyphs.empty())
         return;
 
-    cairo_surface_t *surface = getCairoSurface();
-
-    DBG_ASSERT( surface!=NULL, "no cairo surface for text" );
-    if( !surface )
-        return;
-
     /*
      * It might be ideal to cache surface and cairo context between calls and
      * only destroy it when the drawable changes, but to do that we need to at
      * least change the SalFrame etc impls to dtor the SalGraphics *before* the
      * destruction of the windows they reference
     */
-    cairo_t *cr = cairo_create(surface);
-    cairo_surface_destroy(surface);
+    cairo_t *cr = getCairoContext();
+    if (!cr)
+    {
+        SAL_WARN("vcl", "no cairo context for text");
+        return;
+    }
 
     if (const void *pOptions = Application::GetSettings().GetStyleSettings().GetCairoFontOptions())
         cairo_set_font_options(cr, static_cast<const cairo_font_options_t*>(pOptions));

vcl/unx/generic/gdi/openglx11cairotextrender.cxx

@@ -20,7 +20,7 @@ OpenGLX11CairoTextRender::OpenGLX11CairoTextRender(X11SalGraphics& rParent)
 {
 }
 
-cairo_surface_t* OpenGLX11CairoTextRender::getCairoSurface()
+cairo_t* OpenGLX11CairoTextRender::getCairoContext()
 {
     // static size_t id = 0;
     // OString aFileName = OString("/tmp/libo_logs/text_rendering") + OString::number(id++) + OString(".svg");
@@ -37,7 +37,11 @@ cairo_surface_t* OpenGLX11CairoTextRender::getCairoSurface()
         }
         surface = cairo_image_surface_create( CAIRO_FORMAT_ARGB32, aClipRect.GetWidth(), aClipRect.GetHeight() );
     }
-    return surface;
+    if (!surface)
+        return NULL;
+    cairo_t *cr = cairo_create(surface);
+    cairo_surface_destroy(surface);
+    return cr;
 }
 
 void OpenGLX11CairoTextRender::getSurfaceOffset( double& nDX, double& nDY )

vcl/unx/generic/gdi/openglx11cairotextrender.hxx

@@ -17,7 +17,7 @@ class OpenGLX11CairoTextRender : public X11CairoTextRender
 public:
     OpenGLX11CairoTextRender(X11SalGraphics& rParent);
 
-    virtual cairo_surface_t* getCairoSurface() SAL_OVERRIDE;
+    virtual cairo_t* getCairoContext() SAL_OVERRIDE;
     virtual void getSurfaceOffset(double& nDX, double& nDY) SAL_OVERRIDE;
     virtual void drawSurface(cairo_t* cr) SAL_OVERRIDE;
 };

vcl/unx/generic/gdi/x11cairotextrender.cxx

@@ -52,7 +52,7 @@ GlyphCache& X11CairoTextRender::getPlatformGlyphCache()
     return X11GlyphCache::GetInstance();
 }
 
-cairo_surface_t* X11CairoTextRender::getCairoSurface()
+cairo_t* X11CairoTextRender::getCairoContext()
 {
     // find a XRenderPictFormat compatible with the Drawable
     XRenderPictFormat* pVisualFormat = mrParent.GetXRenderFormat();
@@ -73,7 +73,12 @@ cairo_surface_t* X11CairoTextRender::getCairoSurface()
             mrParent.GetVisual().visual, SAL_MAX_INT16, SAL_MAX_INT16);
     }
 
-    return surface;
+    if (!surface)
+        return NULL;
+
+    cairo_t *cr = cairo_create(surface);
+    cairo_surface_destroy(surface);
+    return cr;
 }
 
 void X11CairoTextRender::getSurfaceOffset( double& nDX, double& nDY )

vcl/unx/generic/gdi/x11cairotextrender.hxx

@@ -40,7 +40,7 @@ public:
     X11CairoTextRender(X11SalGraphics& rParent);
 
     virtual GlyphCache& getPlatformGlyphCache() SAL_OVERRIDE;
-    virtual cairo_surface_t* getCairoSurface() SAL_OVERRIDE;
+    virtual cairo_t* getCairoContext() SAL_OVERRIDE;
     virtual void getSurfaceOffset(double& nDX, double& nDY) SAL_OVERRIDE;
     virtual void clipRegion(cairo_t* cr) SAL_OVERRIDE;
     virtual void drawSurface(cairo_t* cr) SAL_OVERRIDE;