Changeset 21134 for trunk/WebCore/platform/graphics/cairo/GraphicsContextCairo.cpp

Timestamp:

04/26/07 22:11:50 (21 months ago)

Author:

bdash

Message:

2007-04-26 Alp Toker <alp@atoker.com>

Reviewed by Maciej.

http://bugs.webkit.org/show_bug.cgi?id=13505
Cast loses precision on x86_64

• platform/graphics/cairo/GraphicsContextCairo.cpp: (WebCore::GraphicsContext::beginTransparencyLayer): (WebCore::GraphicsContext::endTransparencyLayer): Use a stack of opacity values instead of Cairo user data.

Files:

• trunk/WebCore/platform/graphics/cairo/GraphicsContextCairo.cpp (modified) (3 diffs)

trunk/WebCore/platform/graphics/cairo/GraphicsContextCairo.cpp

@@ -66 +66 @@
 
     cairo_t* context;
-    cairo_user_data_key_t opacityKey;
+    Vector<float> layers;
 };
 
@@ -575 +575 @@
         return;
 
-    ASSERT(opacity >= 0 && opacity <= 1);
-
     cairo_t* context = m_data->context;
     cairo_save(context);
     cairo_push_group(context);
-    // We insert the opacity into a Cairo surface data slot.
-    // Rather than passing a pointer, we store the opacity value directly.
-    void* odata = reinterpret_cast<void*>(static_cast<unsigned int>(opacity * UINT_MAX));
-    cairo_surface_set_user_data(cairo_get_target(context), &m_data->opacityKey, odata, NULL);
+    m_data->layers.append(opacity);
 }
 
@@ -592 +587 @@
 
     cairo_t* context = m_data->context;
-    void* odata = cairo_surface_get_user_data(cairo_get_target(context), &m_data->opacityKey);
-    float opacity = static_cast<float>(reinterpret_cast<unsigned int>(odata)) / UINT_MAX;
-
-    ASSERT(opacity >= 0 && opacity <= 1);
 
     cairo_pop_group_to_source(context);
-    cairo_paint_with_alpha(context, opacity);
+    cairo_paint_with_alpha(context, m_data->layers.last());
+    m_data->layers.removeLast();
     cairo_restore(context);
 }