1 files changed, 159 insertions, 0 deletions
diff --git a/common/gal/cairo/cairo_compositor.cpp b/common/gal/cairo/cairo_compositor.cpp
new file mode 100644
index 0000000..f81cb5a
--- /dev/null
+++ b/common/gal/cairo/cairo_compositor.cpp
@@ -0,0 +1,159 @@
+/*
+ * This program source code file is part of KiCad, a free EDA CAD application.
+ *
+ * Copyright (C) 2013 CERN
+ * @author Maciej Suminski <maciej.suminski@cern.ch>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you may find one here:
+ * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
+ * or you may search the http:O//www.gnu.org website for the version 2 license,
+ * or you may write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+ */
+
+/**
+ * @file cairo_compositor.cpp
+ * @brief Class that handles multitarget rendering (ie. to different textures/surfaces) and
+ * later compositing into a single image (Cairo flavour).
+ */
+
+#include <gal/cairo/cairo_compositor.h>
+#include <wx/log.h>
+
+using namespace KIGFX;
+
+CAIRO_COMPOSITOR::CAIRO_COMPOSITOR( cairo_t** aMainContext ) :
+    m_current( 0 ), m_currentContext( aMainContext ), m_mainContext( *aMainContext )
+{
+    // Do not have uninitialized members:
+    cairo_matrix_init_identity( &m_matrix );
+    m_stride = 0;
+    m_bufferSize = 0;
+}
+
+
+CAIRO_COMPOSITOR::~CAIRO_COMPOSITOR()
+{
+    clean();
+}
+
+
+void CAIRO_COMPOSITOR::Initialize()
+{
+    // Nothing has to be done
+}
+
+
+void CAIRO_COMPOSITOR::Resize( unsigned int aWidth, unsigned int aHeight )
+{
+    clean();
+
+    assert( aWidth > 0 );
+    assert( aHeight > 0 );
+
+    m_width  = aWidth;
+    m_height = aHeight;
+
+    m_stride     = cairo_format_stride_for_width( CAIRO_FORMAT_ARGB32, m_width );
+    m_bufferSize = m_stride * m_height;
+}
+
+
+unsigned int CAIRO_COMPOSITOR::CreateBuffer()
+{
+    // Pixel storage
+    BitmapPtr bitmap( new unsigned int[m_bufferSize] );
+
+    memset( bitmap.get(), 0x00, m_bufferSize * sizeof(int) );
+
+    // Create the Cairo surface
+    cairo_surface_t* surface = cairo_image_surface_create_for_data(
+                                                        (unsigned char*) bitmap.get(),
+                                                        CAIRO_FORMAT_ARGB32, m_width,
+                                                        m_height, m_stride );
+    cairo_t* context = cairo_create( surface );
+#ifdef __WXDEBUG__
+    cairo_status_t status = cairo_status( context );
+    wxASSERT_MSG( status == CAIRO_STATUS_SUCCESS, wxT( "Cairo context creation error" ) );
+#endif /* __WXDEBUG__ */
+
+    // Set default settings for the buffer
+    cairo_set_antialias( context, CAIRO_ANTIALIAS_SUBPIXEL );
+    cairo_set_line_join( context, CAIRO_LINE_JOIN_ROUND );
+    cairo_set_line_cap( context, CAIRO_LINE_CAP_ROUND );
+
+    // Use the same transformation matrix as the main context
+    cairo_get_matrix( m_mainContext, &m_matrix );
+    cairo_set_matrix( context, &m_matrix );
+
+    // Store the new buffer
+    CAIRO_BUFFER buffer = { context, surface, bitmap };
+    m_buffers.push_back( buffer );
+
+    return usedBuffers();
+}
+
+
+void CAIRO_COMPOSITOR::SetBuffer( unsigned int aBufferHandle )
+{
+    wxASSERT_MSG( aBufferHandle <= usedBuffers(), wxT( "Tried to use a not existing buffer" ) );
+
+    // Get currently used transformation matrix, so it can be applied to the new buffer
+    cairo_get_matrix( *m_currentContext, &m_matrix );
+
+    m_current = aBufferHandle - 1;
+    *m_currentContext = m_buffers[m_current].context;
+
+    // Apply the current transformation matrix
+    cairo_set_matrix( *m_currentContext, &m_matrix );
+}
+
+
+void CAIRO_COMPOSITOR::ClearBuffer()
+{
+    // Clear the pixel storage
+    memset( m_buffers[m_current].bitmap.get(), 0x00, m_bufferSize * sizeof(int) );
+}
+
+
+void CAIRO_COMPOSITOR::DrawBuffer( unsigned int aBufferHandle )
+{
+    wxASSERT_MSG( aBufferHandle <= usedBuffers(), wxT( "Tried to use a not existing buffer" ) );
+
+    // Reset the transformation matrix, so it is possible to composite images using
+    // screen coordinates instead of world coordinates
+    cairo_get_matrix( m_mainContext, &m_matrix );
+    cairo_identity_matrix( m_mainContext );
+
+    // Draw the selected buffer contents
+    cairo_set_source_surface( m_mainContext, m_buffers[aBufferHandle - 1].surface, 0.0, 0.0 );
+    cairo_paint( m_mainContext );
+
+    // Restore the transformation matrix
+    cairo_set_matrix( m_mainContext, &m_matrix );
+}
+
+
+void CAIRO_COMPOSITOR::clean()
+{
+    CAIRO_BUFFERS::const_iterator it;
+
+    for( it = m_buffers.begin(); it != m_buffers.end(); ++it )
+    {
+        cairo_destroy( it->context );
+        cairo_surface_destroy( it->surface );
+    }
+
+    m_buffers.clear();
+}