Add ability to use dynamic casting with the return values from more functions,

including:
    Context::get_target()
    Context::get_target() const
    Context::get_source()
    Context::get_source() const
    Context::get_group_target()
    Context::get_group_target() const
    Context::pop_group()
* tests/test-context.cc: a few additional tests to verify the const /
non-const versions both work with dynamic casting.

3 files changed, 117 insertions, 9 deletions

diff --git a/ChangeLog b/ChangeLog
index 09a0255..71f78eb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,19 @@
 2007-07-10  Jonathon Jongsma  <jjongsma@gnome.org>
 
+	* cairomm/context.cc: add ability to use dynamic casting with the return
+	values from more functions, including:
+		Context::get_target()
+		Context::get_target() const
+		Context::get_source()
+		Context::get_source() const
+		Context::get_group_target()
+		Context::get_group_target() const
+		Context::pop_group()
+	* tests/test-context.cc: a few additional tests to verify the const /
+	non-const versions both work with dynamic casting.
+
+2007-07-10  Jonathon Jongsma  <jjongsma@gnome.org>
+
 	* docs/reference/cairomm.css: Improve the documentation style a little bit
 	to make it more readable
 	* docs/reference/Doxyfile.in: build the reference doc for the new
diff --git a/cairomm/context.cc b/cairomm/context.cc
index ea398fc..1b70701 100644
--- a/cairomm/context.cc
+++ b/cairomm/context.cc
@@ -18,6 +18,9 @@
 
 #include <cairomm/context.h>
 #include <cairomm/private.h>
+#include <cairomm/surface.h>
+#include <cairomm/win32_surface.h>
+#include <cairomm/xlib_surface.h>
 
 /* M_PI is defined in math.h in the case of Microsoft Visual C++ */
 #if defined(_MSC_VER)
@@ -538,10 +541,8 @@ Operator Context::get_operator() const
   return result;
 }
 
-RefPtr<Pattern> Context::get_source()
+static RefPtr<Pattern> get_pattern_wrapper (cairo_pattern_t* pattern)
 {
-  cairo_pattern_t* pattern = cairo_get_source(m_cobject);
-  check_object_status_and_throw_exception(*this);
   cairo_pattern_type_t pattern_type = cairo_pattern_get_type (pattern);
   switch (pattern_type)
   {
@@ -562,11 +563,18 @@ RefPtr<Pattern> Context::get_source()
   }
 }
 
+RefPtr<Pattern> Context::get_source()
+{
+  cairo_pattern_t* pattern = cairo_get_source(m_cobject);
+  check_object_status_and_throw_exception(*this);
+  return get_pattern_wrapper (pattern);
+}
+
 RefPtr<const Pattern> Context::get_source() const
 {
   cairo_pattern_t* pattern = cairo_get_source(m_cobject);
   check_object_status_and_throw_exception(*this);
-  return RefPtr<const Pattern>(new Pattern(pattern, false /* does not have reference */));
+  return RefPtr<const Pattern>::cast_const (get_pattern_wrapper (pattern));
 }
 
 double Context::get_tolerance() const
@@ -644,18 +652,72 @@ void Context::get_matrix(Matrix& matrix)
   check_object_status_and_throw_exception(*this);
 }
 
+static
+RefPtr<Surface> get_surface_wrapper (cairo_surface_t* surface)
+{
+  cairo_surface_type_t surface_type = cairo_surface_get_type (surface);
+  switch (surface_type)
+  {
+    case CAIRO_SURFACE_TYPE_IMAGE:
+      return RefPtr<ImageSurface>(new ImageSurface(surface, false /* does not have reference */));
+      break;
+#if CAIRO_HAS_PDF_SURFACE
+    case CAIRO_SURFACE_TYPE_PDF:
+      return RefPtr<PdfSurface>(new PdfSurface(surface, false /* does not have reference */));
+      break;
+#endif
+#if CAIRO_HAS_PS_SURFACE
+    case CAIRO_SURFACE_TYPE_PS:
+      return RefPtr<PsSurface>(new PsSurface(surface, false /* does not have reference */));
+      break;
+#endif
+#if CAIRO_HAS_XLIB_SURFACE
+    case CAIRO_SURFACE_TYPE_XLIB:
+      return RefPtr<XlibSurface>(new XlibSurface(surface, false /* does not have reference */));
+      break;
+#endif
+#if CAIRO_HAS_GLITZ_SURFACE
+    case CAIRO_SURFACE_TYPE_GLITZ:
+      return RefPtr<GlitzSurface>(new GlitzSurface(surface, false /* does not have reference */));
+      break;
+#endif
+#if CAIRO_HAS_QUARTZ_SURFACE
+    case CAIRO_SURFACE_TYPE_QUARTZ:
+      return RefPtr<QuartzSurface>(new QuartzSurface(surface, false /* does not have reference */));
+      break;
+#endif
+#if CAIRO_HAS_WIN32_SURFACE
+    case CAIRO_SURFACE_TYPE_WIN32:
+      return RefPtr<Win32Surface>(new Win32Surface(surface, false /* does not have reference */));
+      break;
+#endif
+#if CAIRO_HAS_SVG_SURFACE
+    case CAIRO_SURFACE_TYPE_SVG:
+      return RefPtr<SvgSurface>(new SvgSurface(surface, false /* does not have reference */));
+      break;
+#endif
+    // the following surfaces are not directly supported in cairomm yet
+    case CAIRO_SURFACE_TYPE_DIRECTFB:
+    case CAIRO_SURFACE_TYPE_OS2:
+    case CAIRO_SURFACE_TYPE_BEOS:
+    case CAIRO_SURFACE_TYPE_XCB:
+    default:
+      return RefPtr<Surface>(new Surface(surface, false /* does not have reference */));
+  }
+}
+
 RefPtr<Surface> Context::get_target()
 {
   cairo_surface_t* surface = cairo_get_target(const_cast<cairo_t*>(m_cobject));
   check_object_status_and_throw_exception(*this);
-  return RefPtr<Surface>(new Surface(surface, false /* does not have reference */));
+  return get_surface_wrapper (surface);
 }
 
 RefPtr<const Surface> Context::get_target() const
 {
   cairo_surface_t* surface = cairo_get_target(const_cast<cairo_t*>(m_cobject));
   check_object_status_and_throw_exception(*this);
-  return RefPtr<const Surface>(new Surface(surface, false /* does not have reference */));
+  return RefPtr<const Surface>::cast_const (get_surface_wrapper (surface));
 }
 
 Path* Context::copy_path() const
@@ -694,7 +756,7 @@ RefPtr<Pattern> Context::pop_group()
 {
   cairo_pattern_t* pattern = cairo_pop_group(m_cobject);
   check_object_status_and_throw_exception(*this);
-  return RefPtr<Pattern>(new Pattern(pattern));
+  return get_pattern_wrapper(pattern);
 }
 
 void Context::pop_group_to_source()
@@ -713,7 +775,7 @@ RefPtr<Surface> Context::get_group_target()
     throw_exception(CAIRO_STATUS_NULL_POINTER);
   }
 
-  return RefPtr<Surface>(new Surface(surface, false));
+  return get_surface_wrapper(surface);
 }
 
 RefPtr<const Surface> Context::get_group_target() const
@@ -726,7 +788,7 @@ RefPtr<const Surface> Context::get_group_target() const
     throw_exception(CAIRO_STATUS_NULL_POINTER);
   }
 
-  return RefPtr<const Surface>(new Surface(surface, false));
+  return get_surface_wrapper(surface);
 }
 
 } //namespace Cairo
diff --git a/tests/test-context.cc b/tests/test-context.cc
index 1583842..9cfaec2 100644
--- a/tests/test-context.cc
+++ b/tests/test-context.cc
@@ -97,6 +97,12 @@ test_source ()
     BOOST_CHECK_EQUAL (1.0, r);
     BOOST_CHECK_EQUAL (0.5, g);
     BOOST_CHECK_EQUAL (0.25, b);
+
+    // now try for const objects..
+    Cairo::RefPtr<const Cairo::Context> cr2 = cr;
+    Cairo::RefPtr<const Cairo::SolidPattern> retrieved_solid2 =
+      Cairo::RefPtr<const Cairo::SolidPattern>::cast_dynamic(cr2->get_source ());
+    BOOST_REQUIRE (retrieved_solid2);
   }
 
   cr->set_source (gradient_pattern);
@@ -288,6 +294,31 @@ test_current_point ()
   BOOST_CHECK (y == 3.0);
 }
 
+void
+test_target ()
+{
+  Cairo::RefPtr<Cairo::Surface> surf = Cairo::ImageSurface::create(Cairo::FORMAT_ARGB32, 10, 10); \
+  Cairo::RefPtr<Cairo::Context> cr = Cairo::Context::create(surf);
+
+  Cairo::RefPtr<Cairo::ImageSurface> target_surface =
+    Cairo::RefPtr<Cairo::ImageSurface>::cast_dynamic(cr->get_target ());
+  Cairo::RefPtr<Cairo::PdfSurface> bad_surface =
+    Cairo::RefPtr<Cairo::PdfSurface>::cast_dynamic(cr->get_target ());
+  BOOST_CHECK (target_surface);
+  BOOST_CHECK (!bad_surface);
+
+  // now check for const objects...
+  Cairo::RefPtr<const Cairo::Context> cr2 = Cairo::Context::create(surf);
+
+  Cairo::RefPtr<const Cairo::ImageSurface> target_surface2 =
+    Cairo::RefPtr<const Cairo::ImageSurface>::cast_dynamic(cr2->get_target ());
+  Cairo::RefPtr<const Cairo::PdfSurface> bad_surface2 =
+    Cairo::RefPtr<const Cairo::PdfSurface>::cast_dynamic(cr2->get_target ());
+  BOOST_CHECK (target_surface2);
+  BOOST_CHECK (!bad_surface2);
+
+}
+
 test_suite*
 init_unit_test_suite(int argc, char* argv[])
 {
@@ -312,6 +343,7 @@ init_unit_test_suite(int argc, char* argv[])
   test->add (BOOST_TEST_CASE (&test_draw));
   test->add (BOOST_TEST_CASE (&test_clip));
   test->add (BOOST_TEST_CASE (&test_current_point));
+  test->add (BOOST_TEST_CASE (&test_target));
 
   return test;
 }