Upgrade gtktiledviewer to use its own buffer.

Change-Id: I3f567ff19ee0d5b0d54aeef9b163b78567d72946

1 files changed, 29 insertions, 13 deletions

diff --git a/desktop/qa/gtktiledviewer/gtktiledviewer.cxx b/desktop/qa/gtktiledviewer/gtktiledviewer.cxx
index 51d9414198ee..2ffa59907171 100644
--- a/desktop/qa/gtktiledviewer/gtktiledviewer.cxx
+++ b/desktop/qa/gtktiledviewer/gtktiledviewer.cxx
@@ -32,6 +32,7 @@ static int help()
 }
 
 static GtkWidget* ourCanvas;
+static GdkPixbuf* ourPixBuf = 0;
 
 bool drawCallback(GtkWidget* /* The eventbox */, void* /* cairo_t* cr */, gpointer pData)
 {
@@ -46,25 +47,41 @@ bool drawCallback(GtkWidget* /* The eventbox */, void* /* cairo_t* cr */, gpoint
     int nRenderWidth = nWidth / 10;
     int nRenderHeight = nHeight / 10;
     int nRowStride;
-    unsigned char* pBuffer = pDocument->paintTile( nRenderWidth, nRenderHeight,
-                                                   &nRowStride,
-                                                   0, 0, // origin
-                                                   nWidth, nHeight );
+
+    if ( ourPixBuf &&
+            (gdk_pixbuf_get_width( ourPixBuf ) != nRenderWidth ||
+             gdk_pixbuf_get_height( ourPixBuf ) != nRenderHeight ) )
+    {
+        g_object_unref( G_OBJECT( ourPixBuf ) );
+        ourPixBuf = 0;
+
+    }
+    if (!ourPixBuf)
+    {
+        ourPixBuf = gdk_pixbuf_new( GDK_COLORSPACE_RGB,
+                                    true, 8,
+                                    nRenderWidth, nRenderHeight);
+    }
+
+    unsigned char* pBuffer = gdk_pixbuf_get_pixels( ourPixBuf );
+
+    pDocument->paintTile( pBuffer,
+                          nRenderWidth, nRenderHeight,
+                          &nRowStride,
+                          0, 0, // origin
+                          nWidth, nHeight );
+    // TODO: double check that the rowstride really matches what we expected,
+    // although presumably we'd already be crashing by now if things were
+    // wrong.
+    (void) nRowStride;
 
     for (int i = 3; i < nRowStride*nRenderHeight; i += 4)
     {
         pBuffer[i] = 0xFF;
     }
 
-    GdkPixbuf* pBixBuf = gdk_pixbuf_new_from_data( pBuffer, GDK_COLORSPACE_RGB,
-                                                   true, 8,
-                                                   nRenderWidth, nRenderHeight,
-                                                   nRowStride,
-                                                   0, 0 );
-    pBixBuf = gdk_pixbuf_flip( pBixBuf, false );
-    gtk_image_set_from_pixbuf( GTK_IMAGE(ourCanvas), pBixBuf );
+    gtk_image_set_from_pixbuf( GTK_IMAGE( ourCanvas ), ourPixBuf );
 
-    // TODO: we need to keep track of and cleanup these buffers etc.
     return true;
 
 }
@@ -108,7 +125,6 @@ int main( int argc, char* argv[] )
     ourCanvas = pCanvas;
     gtk_container_add( GTK_CONTAINER( pEventBox ), pCanvas );
 
-
     g_signal_connect( G_OBJECT(pEventBox), "button-press-event", G_CALLBACK(drawCallback), pDocument);
 
     gtk_widget_show( pCanvas );