gtk3: move createCairoContext down to svpgdi

(cherry picked from commit 253c0f07)

Change-Id: Ib3c6d6689c4b79a636a3f2f0f985f3573aa46f3d

cairo_format_stride_for_width is 1.6 onwards

(cherry picked from commit 5ce9954c)

Change-Id: Ic233b4b6c7067f2473eb76b0c7e520cfe1dfcd14

vcl/headless/svpgdi.cxx

@@ -32,6 +32,10 @@
 #include <basegfx/polygon/b2dpolygontools.hxx>
 #include <basebmp/scanlineformats.hxx>
 
+#if ENABLE_CAIRO_CANVAS
+#include <cairo.h>
+#endif
+
 #if OSL_DEBUG_LEVEL > 2
 #include <basebmp/debug.hxx>
 #include <fstream>
@@ -737,6 +741,35 @@ bool SvpSalGraphics::supportsOperation( OutDevSupportType ) const
 
 #endif
 
+#if ENABLE_CAIRO_CANVAS
+
+cairo_t* SvpSalGraphics::createCairoContext(const basebmp::BitmapDeviceSharedPtr &rBuffer)
+{
+#if CAIRO_VERSION >= CAIRO_VERSION_ENCODE(1, 6, 0)
+    if (rBuffer->getScanlineFormat() != basebmp::FORMAT_THIRTYTWO_BIT_TC_MASK_BGRX)
+        return NULL;
+
+    basegfx::B2IVector size = rBuffer->getSize();
+    sal_Int32 nStride = rBuffer->getScanlineStride();
+    if (cairo_format_stride_for_width(CAIRO_FORMAT_RGB24, size.getX()) != nStride)
+        return NULL;
+
+    basebmp::RawMemorySharedArray data = rBuffer->getBuffer();
+    cairo_surface_t *target =
+        cairo_image_surface_create_for_data(data.get(),
+                                        CAIRO_FORMAT_RGB24,
+                                        size.getX(), size.getY(),
+                                        nStride);
+    cairo_t* cr = cairo_create(target);
+    cairo_surface_destroy(target);
+    return cr;
+#else
+    return NULL;
+#endif
+}
+
+#endif
+
 bool SvpSalGraphics::SupportsCairo() const
 {
     return false;

vcl/inc/headless/svpgdi.hxx

@@ -24,6 +24,7 @@
 #include <basebmp/color.hxx>
 #include <vcl/sysdata.hxx>
 #include <vcl/metric.hxx>
+#include <config_cairo_canvas.h>
 
 #include "salgdi.hxx"
 #include "sallayout.hxx"
@@ -35,6 +36,7 @@
 
 class GlyphCache;
 class ServerFont;
+typedef struct _cairo cairo_t;
 
 class VCL_DLLPUBLIC SvpSalGraphics : public SalGraphics
 {
@@ -207,6 +209,12 @@ public:
 
     virtual SystemFontData  GetSysFontData( int nFallbacklevel ) const SAL_OVERRIDE;
 
+#if ENABLE_CAIRO_CANVAS
+
+    static cairo_t*         createCairoContext(const basebmp::BitmapDeviceSharedPtr& rBuffer);
+
+#endif // ENABLE_CAIRO_CANVAS
+
     virtual void            BeginPaint() SAL_OVERRIDE { };
     virtual void            EndPaint() SAL_OVERRIDE { };
 };

vcl/unx/gtk/window/gtksalframe.cxx

@@ -3550,17 +3550,8 @@ gboolean GtkSalFrame::signalCrossing( GtkWidget*, GdkEventCrossing* pEvent, gpoi
 
 cairo_t* GtkSalFrame::getCairoContext() const
 {
-    basebmp::RawMemorySharedArray data = m_aFrame->getBuffer();
-    basegfx::B2IVector size = m_aFrame->getSize();
-    sal_Int32 nStride = m_aFrame->getScanlineStride();
-    assert(cairo_format_stride_for_width(CAIRO_FORMAT_RGB24, size.getX()) == nStride);
-    cairo_surface_t *target =
-        cairo_image_surface_create_for_data(data.get(),
-                                        CAIRO_FORMAT_RGB24,
-                                        size.getX(), size.getY(),
-                                        nStride);
-    cairo_t* cr = cairo_create(target);
-    cairo_surface_destroy(target);
+    cairo_t* cr = SvpSalGraphics::createCairoContext(m_aFrame);
+    assert(cr);
     return cr;
 }