Restore "Use the cairo-compatible basebmp surface for headless"

as it now works again after ancient emf import bug is fixed by

commit 5e5b90c12862b522a4553337fbf6309bb8278b8c
Date:   Thu Feb 26 13:47:58 2015 +0000
in BITFIELDS mode (3) there are *3* pal entries not 12

and two writer qa tests adapted to test for the actual pixel color vs the
underlying pixel data

This reverts commit 3c4f7704e0af64bf967f5f767bf4b4cff7f59d6c.

Change-Id: Id94f98f9c620c90fda097fa97fc34c9ee957c483

1 files changed, 17 insertions, 33 deletions

diff --git a/vcl/unx/gtk3/gdi/gtk3salnativewidgets-gtk.cxx b/vcl/unx/gtk3/gdi/gtk3salnativewidgets-gtk.cxx
index ac708fc5e1b7..e23f10318a24 100644
--- a/vcl/unx/gtk3/gdi/gtk3salnativewidgets-gtk.cxx
+++ b/vcl/unx/gtk3/gdi/gtk3salnativewidgets-gtk.cxx
@@ -912,7 +912,6 @@ bool GtkSalGraphics::drawNativeControl( ControlType nType, ControlPart nPart, co
     cairo_surface_t* surface = cairo_image_surface_create(CAIRO_FORMAT_ARGB32,
                                                           translatedRegion.width, translatedRegion.height);
     cairo_t *cr = cairo_create(surface);
-    cairo_surface_destroy(surface); // unref
 
     gtk_style_context_save(context);
     gtk_style_context_set_state(context, flags);
@@ -960,18 +959,14 @@ bool GtkSalGraphics::drawNativeControl( ControlType nType, ControlPart nPart, co
         break;
     }
 
-    gtk_style_context_restore(context);
-
-    renderAreaToPix(cr, &translatedRegion);
     cairo_destroy(cr); // unref
+    renderAreaToPix(surface, &translatedRegion);
+    cairo_surface_destroy(surface); // unref
 
     return true;
 }
 
-// FIXME: This is incredibly lame... but so is cairo's insistence on - exactly -
-// its own stride - neither more nor less - particularly not more aligned
-// we like 8byte aligned, it likes 4 - most odd.
-void GtkSalGraphics::renderAreaToPix( cairo_t *cr,
+void GtkSalGraphics::renderAreaToPix( cairo_surface_t *source,
                                       cairo_rectangle_int_t *region)
 {
     if( !mpFrame->m_aFrame.get() )
@@ -982,33 +977,22 @@ void GtkSalGraphics::renderAreaToPix( cairo_t *cr,
     sal_Int32 nStride = mpFrame->m_aFrame->getScanlineStride();
     long ax = region->x;
     long ay = region->y;
-    long awidth = region->width;
-
-    /* Get the cairo surface and the data */
-    cairo_surface_t* surface = cairo_get_target(cr);
-    g_assert(surface != NULL);
-    cairo_surface_flush(surface);
-    unsigned char* cairo_data = cairo_image_surface_get_data(surface);
-    g_assert(cairo_data != NULL);
-    int cairo_stride = cairo_format_stride_for_width (CAIRO_FORMAT_ARGB32, awidth);
-
-    unsigned char *src = data.get();
-    src += (int)ay * nStride + (int)ax * 3;
-    awidth = MIN (region->width, size.getX() - ax);
+    long awidth = MIN (region->width, size.getX() - ax);
     long aheight = MIN (region->height, size.getY() - ay);
 
-    for (int y = 0; y < aheight; ++y)
-    {
-        for (int x = 0; x < awidth && y < aheight; ++x)
-        {
-            double alpha = ((float)cairo_data[x*4 + 3])/255.0;
-            src[x*3 + 0] = src[x*3 + 0] * (1.0 - alpha) + cairo_data[x*4+0];
-            src[x*3 + 1] = src[x*3 + 1] * (1.0 - alpha) + cairo_data[x*4+1];
-            src[x*3 + 2] = src[x*3 + 2] * (1.0 - alpha) + cairo_data[x*4+2];
-        }
-        src += nStride;
-        cairo_data += cairo_stride;
-    }
+    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_set_source_surface( cr, source, ax, ay );
+    cairo_rectangle( cr, ax, ay, awidth, aheight );
+    cairo_fill( cr );
+    cairo_destroy(cr);
+    cairo_surface_destroy(target);
+
     if ( !mpFrame->isDuringRender() )
         gtk_widget_queue_draw_area( mpFrame->getWindow(), ax, ay, awidth, aheight );
 }