[Webkit-unassigned] [Bug 45423] [Gtk] Port tiled backing store

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=45423


Martin Robinson <mrobinson at webkit.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #68178|review?                     |review-
               Flag|                            |




--- Comment #4 from Martin Robinson <mrobinson at webkit.org>  2010-09-21 09:42:52 PST ---
(From update of attachment 68178)
View in context: https://bugs.webkit.org/attachment.cgi?id=68178&action=review

This patch looks good, in general, but I think I'd rather see this implemented in terms of the Cairo API as much as possible. We really want to avoid GdkPixmap/GdkPixbuf as much as possible and especially deprecated APIs like GdkRegion.

> WebCore/platform/graphics/Tile.h:82
> +    GdkPixmap* m_buffer;
> +    GdkRegion* m_dirtyRegion;

Instead of using GdkPixmap, I'd like to see a GRefPtr<cairo_surface_t> here. GdkRegion is deprecated in recent GDK releases (replaced by cairo regions), so you'll either have to figure out some version independent method or use #ifdefs.

> WebCore/platform/graphics/gtk/TileGtk.cpp:61
> +        Color color1(checkerColor1);
> +        Color color2(checkerColor2);
> +        float red1, green1, blue1, alpha1;
> +        float red2, green2, blue2, alpha2;
> +        color1.getRGBA(red1, green1, blue1, alpha1);
> +        color2.getRGBA(red2, green2, blue2, alpha2);
> +        for (unsigned y = 0; y < checkerSize; y += checkerSize / 2) {
> +            bool alternate = y % checkerSize;
> +            for (unsigned x = 0; x < checkerSize; x += checkerSize / 2) {
> +                cairo_rectangle(cr, x, y, checkerSize / 2, checkerSize /2);
> +                if (alternate)
> +                    cairo_set_source_rgb(cr, red1, green1, blue1);
> +                else
> +                    cairo_set_source_rgb(cr, red2, green2, blue2);
> +                cairo_fill(cr);
> +                alternate = !alternate;

I think it might be cleaner to use the stippling approach that Benjamin Otte oulined here: http://blogs.gnome.org/otte/2010/07/27/rendering-cleanup/

> WebCore/platform/graphics/gtk/TileGtk.cpp:119
> +        if (!m_buffer) {
> +            m_backBuffer = gdk_pixmap_new(0,
> +                               m_backingStore->m_tileSize.width(),
> +                               m_backingStore->m_tileSize.height(),
> +                               gdk_visual_get_depth(gdk_visual_get_system()));
> +        } else {

WebKit code style requires many block types with only one statement to omit the curly braces.

> WebCore/platform/graphics/gtk/TileGtk.cpp:154
> +    if (m_buffer)
> +        g_object_unref(m_buffer);

The use of GRefPtr would elminate the need to do this.

> WebCore/platform/graphics/gtk/TileGtk.cpp:170
> +                   target.height());
> +

Line lengths in the project can be ~120+ characters. So this should be:
    IntRect source((target.x() - m_rect.x()), (target.y() - m_rect.y()), target.height());

> WebCore/platform/graphics/gtk/TileGtk.cpp:178
> +    cairo_t* cairoContextSource = gdk_cairo_create(m_buffer);
> +    cairo_set_source_surface(
> +        cairoContext,
> +        cairo_get_target(cairoContextSource),
> +        target.x() - source.x(),
> +        target.y() - source.y());

Using a Cairo surface as the buffer will eliminate some of this and allow you do just do something like:
cairo_set_source_surface(cairoContxt, m_buffer.get(), target.x() - source.x(), target.y() - source.y());

-- 
Configure bugmail: https://bugs.webkit.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.