Source/WebCore/platform/gtk/WidgetRenderingContext.cpp - WebKit - Git at Google

 /*
  * Copyright (C) 2010 Sencha, Inc.
  * Copyright (C) 2010 Igalia S.L.
  *
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 #ifdef GTK_API_VERSION_2

 #include "config.h"
 #include "WidgetRenderingContext.h"

 #include "GraphicsContext.h"
 #include "GtkVersioning.h"
 #include "PlatformContextCairo.h"
 #include "RefPtrCairo.h"
 #include "RenderThemeGtk.h"
 #include "Timer.h"
 #include <gdk/gdk.h>
 #include <gtk/gtk.h>
 #include <wtf/StdLibExtras.h>

 namespace WebCore {

 static GdkPixmap* gScratchBuffer = 0;
 static void purgeScratchBuffer()
 {
     if (gScratchBuffer)
         g_object_unref(gScratchBuffer);
     gScratchBuffer = 0;
 }

 // Widget rendering needs a scratch image as the buffer for the intermediate
 // render. Instead of creating and destroying the buffer for every operation,
 // we create a buffer which will be automatically purged via a timer.
 class PurgeScratchBufferTimer : public TimerBase {
 private:
     virtual void fired() { purgeScratchBuffer(); }
 };

 static void scheduleScratchBufferPurge()
 {
     DEFINE_STATIC_LOCAL(PurgeScratchBufferTimer, purgeScratchBufferTimer, ());
     if (purgeScratchBufferTimer.isActive())
         purgeScratchBufferTimer.stop();
     purgeScratchBufferTimer.startOneShot(2);
 }

 WidgetRenderingContext::WidgetRenderingContext(GraphicsContext* graphicsContext, const IntRect& targetRect)
     : m_graphicsContext(graphicsContext)
     , m_targetRect(targetRect)
     , m_hadError(false)
 {
     RenderThemeGtk* theme = static_cast<RenderThemeGtk*>(RenderTheme::defaultTheme().get());

     // Fallback: We failed to create an RGBA colormap earlier, so we cannot properly paint
     // to a temporary surface and preserve transparency. To ensure decent widget rendering, just
     // paint directly to the target drawable. This will not render CSS rotational transforms properly.
     if (!theme->m_themePartsHaveRGBAColormap && graphicsContext->gdkWindow()) {
         m_target = graphicsContext->gdkWindow();
         return;
     }

     // We never want to create a scratch buffer larger than the size of our target GdkDrawable.
     // This prevents giant pixmap allocations for very large widgets in smaller views.
     // FIXME: We need to implement this check for WebKit2 as well.
     if (graphicsContext->gdkWindow()) {
         int maxWidth = 0, maxHeight = 0;
         getGdkDrawableSize(graphicsContext->gdkWindow(), &maxWidth, &maxHeight);
         m_targetRect.setSize(m_targetRect.size().shrunkTo(IntSize(maxWidth, maxHeight)));
     }

     // Widgets sometimes need to draw outside their boundaries for things such as
     // exterior focus. We want to allocate a some extra pixels in our surface for this.
     static int extraSpace = 15;
     m_targetRect.inflate(extraSpace);

     // This offset will map a point in the coordinate system of the widget to the coordinate system of the painting buffer.
     m_paintOffset = targetRect.location() - m_targetRect.location();

     int width = m_targetRect.width() + (extraSpace * 2);
     int height = m_targetRect.height() + (extraSpace * 2);
     int scratchWidth = 0;
     int scratchHeight = 0;
     if (gScratchBuffer)
         gdk_pixmap_get_size(gScratchBuffer, &scratchWidth, &scratchHeight);

     // We do not need to recreate the buffer if the current buffer is large enough.
     if (!gScratchBuffer || scratchWidth < width || scratchHeight < height) {
         purgeScratchBuffer();
         // Round to the nearest 32 pixels so we do not grow the buffer for similar sized requests.
         width = (1 + (width >> 5)) << 5;
         height = (1 + (height >> 5)) << 5;

         gScratchBuffer = gdk_pixmap_new(0, width, height, gdk_colormap_get_visual(theme->m_colormap)->depth);
         gdk_drawable_set_colormap(gScratchBuffer, theme->m_colormap);
     }
     m_target = gScratchBuffer;

     // Clear the scratch buffer.
     RefPtr<cairo_t> scratchBufferContext = adoptRef(gdk_cairo_create(gScratchBuffer));
     cairo_set_operator(scratchBufferContext.get(), CAIRO_OPERATOR_CLEAR);
     cairo_paint(scratchBufferContext.get());
 }

 WidgetRenderingContext::~WidgetRenderingContext()
 {
     // We do not need to blit back to the target in the fallback case. See above.
     RenderThemeGtk* theme = static_cast<RenderThemeGtk*>(RenderTheme::defaultTheme().get());
     if (!theme->m_themePartsHaveRGBAColormap && m_graphicsContext->gdkWindow())
         return;

     // Don't paint the results back if there was an error.
     if (m_hadError) {
         scheduleScratchBufferPurge();
         return;
     }

     // FIXME: It's unclear if it is necessary to preserve the current source here.
     cairo_t* cairoContext = m_graphicsContext->platformContext()->cr();
     RefPtr<cairo_pattern_t> previousSource(cairo_get_source(cairoContext));

     gdk_cairo_set_source_pixmap(cairoContext, gScratchBuffer, m_targetRect.x(), m_targetRect.y());
     cairo_rectangle(cairoContext, m_targetRect.x(), m_targetRect.y(), m_targetRect.width(), m_targetRect.height());
     cairo_fill(cairoContext);
     cairo_set_source(cairoContext, previousSource.get());
     scheduleScratchBufferPurge();
 }

 void WidgetRenderingContext::calculateClipRect(const IntRect& rect, GdkRectangle* clipRect)
 {
     clipRect->x = m_paintOffset.width() + rect.x();
     clipRect->y = m_paintOffset.height() + rect.y();
     clipRect->width = m_targetRect.width();
     clipRect->height = m_targetRect.height();
 }

 void WidgetRenderingContext::gtkPaintBox(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail)
 {
     GdkRectangle clipRect;
     calculateClipRect(rect, &clipRect);

     // Some widgets also need their allocation adjusted to account for extra space.
     // Right now only scrollbar buttons have significant allocations.
     GtkAllocation allocation;
     gtk_widget_get_allocation(widget, &allocation);
     allocation.x += clipRect.x;
     allocation.y += clipRect.y;
     gtk_widget_set_allocation(widget, &allocation);

     gtk_paint_box(gtk_widget_get_style(widget), m_target, stateType, shadowType, &clipRect,
                   widget, detail, clipRect.x, clipRect.y, rect.width(), rect.height());
 }

 void WidgetRenderingContext::gtkPaintFlatBox(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail)
 {
     GdkRectangle clipRect;
     calculateClipRect(rect, &clipRect);
     gtk_paint_flat_box(gtk_widget_get_style(widget), m_target, stateType, shadowType, &clipRect,
                        widget, detail, clipRect.x, clipRect.y, rect.width(), rect.height());
 }

 void WidgetRenderingContext::gtkPaintFocus(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, const gchar* detail)
 {
     GdkRectangle clipRect;
     calculateClipRect(rect, &clipRect);
     gtk_paint_focus(gtk_widget_get_style(widget), m_target, stateType, &clipRect, widget,
                     detail, clipRect.x, clipRect.y, rect.width(), rect.height());
 }

 void WidgetRenderingContext::gtkPaintSlider(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail, GtkOrientation orientation)
 {
     GdkRectangle clipRect;
     calculateClipRect(rect, &clipRect);
     gtk_paint_slider(gtk_widget_get_style(widget), m_target, stateType, shadowType, &clipRect, widget,
                      detail, clipRect.x, clipRect.y, rect.width(), rect.height(), orientation);
 }

 void WidgetRenderingContext::gtkPaintCheck(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail)
 {
     GdkRectangle clipRect;
     calculateClipRect(rect, &clipRect);
     gtk_paint_check(gtk_widget_get_style(widget), m_target, stateType, shadowType, &clipRect, widget,
                     detail, clipRect.x, clipRect.y, rect.width(), rect.height());
 }

 void WidgetRenderingContext::gtkPaintOption(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail)
 {
     GdkRectangle clipRect;
     calculateClipRect(rect, &clipRect);
     gtk_paint_option(gtk_widget_get_style(widget), m_target, stateType, shadowType, &clipRect, widget,
                      detail, clipRect.x, clipRect.y, rect.width(), rect.height());
 }

 void WidgetRenderingContext::gtkPaintShadow(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail)
 {
     GdkRectangle clipRect;
     calculateClipRect(rect, &clipRect);
     gtk_paint_shadow(gtk_widget_get_style(widget), m_target, stateType, shadowType, &clipRect, widget,
                      detail, clipRect.x, clipRect.y, rect.width(), rect.height());
 }

 void WidgetRenderingContext::gtkPaintArrow(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, int arrowDirection, const gchar* detail)
 {
     GdkRectangle clipRect;
     calculateClipRect(rect, &clipRect);
     gtk_paint_arrow(gtk_widget_get_style(widget), m_target, stateType, shadowType, &clipRect, widget, detail,
                     static_cast<GtkArrowType>(arrowDirection), TRUE, clipRect.x, clipRect.y, rect.width(), rect.height());
 }

 void WidgetRenderingContext::gtkPaintVLine(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, const gchar* detail)
 {
     GdkRectangle clipRect;
     calculateClipRect(rect, &clipRect);
     gtk_paint_vline(gtk_widget_get_style(widget), m_target, stateType, &clipRect, widget, detail,
                     clipRect.y, clipRect.y + rect.height(), clipRect.x);

 }

 }

 #endif // GTK_API_VERSION_2
	/*
	* Copyright (C) 2010 Sencha, Inc.
	* Copyright (C) 2010 Igalia S.L.
	*
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	*
	* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
	* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
	* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
	* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
	* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
	* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#ifdef GTK_API_VERSION_2

	#include "config.h"
	#include "WidgetRenderingContext.h"

	#include "GraphicsContext.h"
	#include "GtkVersioning.h"
	#include "PlatformContextCairo.h"
	#include "RefPtrCairo.h"
	#include "RenderThemeGtk.h"
	#include "Timer.h"
	#include <gdk/gdk.h>
	#include <gtk/gtk.h>
	#include <wtf/StdLibExtras.h>

	namespace WebCore {

	static GdkPixmap* gScratchBuffer = 0;
	static void purgeScratchBuffer()
	{
	if (gScratchBuffer)
	g_object_unref(gScratchBuffer);
	gScratchBuffer = 0;
	}

	// Widget rendering needs a scratch image as the buffer for the intermediate
	// render. Instead of creating and destroying the buffer for every operation,
	// we create a buffer which will be automatically purged via a timer.
	class PurgeScratchBufferTimer : public TimerBase {
	private:
	virtual void fired() { purgeScratchBuffer(); }
	};

	static void scheduleScratchBufferPurge()
	{
	DEFINE_STATIC_LOCAL(PurgeScratchBufferTimer, purgeScratchBufferTimer, ());
	if (purgeScratchBufferTimer.isActive())
	purgeScratchBufferTimer.stop();
	purgeScratchBufferTimer.startOneShot(2);
	}

	WidgetRenderingContext::WidgetRenderingContext(GraphicsContext* graphicsContext, const IntRect& targetRect)
	: m_graphicsContext(graphicsContext)
	, m_targetRect(targetRect)
	, m_hadError(false)
	{
	RenderThemeGtk* theme = static_cast<RenderThemeGtk*>(RenderTheme::defaultTheme().get());

	// Fallback: We failed to create an RGBA colormap earlier, so we cannot properly paint
	// to a temporary surface and preserve transparency. To ensure decent widget rendering, just
	// paint directly to the target drawable. This will not render CSS rotational transforms properly.
	if (!theme->m_themePartsHaveRGBAColormap && graphicsContext->gdkWindow()) {
	m_target = graphicsContext->gdkWindow();
	return;
	}

	// We never want to create a scratch buffer larger than the size of our target GdkDrawable.
	// This prevents giant pixmap allocations for very large widgets in smaller views.
	// FIXME: We need to implement this check for WebKit2 as well.
	if (graphicsContext->gdkWindow()) {
	int maxWidth = 0, maxHeight = 0;
	getGdkDrawableSize(graphicsContext->gdkWindow(), &maxWidth, &maxHeight);
	m_targetRect.setSize(m_targetRect.size().shrunkTo(IntSize(maxWidth, maxHeight)));
	}

	// Widgets sometimes need to draw outside their boundaries for things such as
	// exterior focus. We want to allocate a some extra pixels in our surface for this.
	static int extraSpace = 15;
	m_targetRect.inflate(extraSpace);

	// This offset will map a point in the coordinate system of the widget to the coordinate system of the painting buffer.
	m_paintOffset = targetRect.location() - m_targetRect.location();

	int width = m_targetRect.width() + (extraSpace * 2);
	int height = m_targetRect.height() + (extraSpace * 2);
	int scratchWidth = 0;
	int scratchHeight = 0;
	if (gScratchBuffer)
	gdk_pixmap_get_size(gScratchBuffer, &scratchWidth, &scratchHeight);

	// We do not need to recreate the buffer if the current buffer is large enough.
	if (!gScratchBuffer \|\| scratchWidth < width \|\| scratchHeight < height) {
	purgeScratchBuffer();
	// Round to the nearest 32 pixels so we do not grow the buffer for similar sized requests.
	width = (1 + (width >> 5)) << 5;
	height = (1 + (height >> 5)) << 5;

	gScratchBuffer = gdk_pixmap_new(0, width, height, gdk_colormap_get_visual(theme->m_colormap)->depth);
	gdk_drawable_set_colormap(gScratchBuffer, theme->m_colormap);
	}
	m_target = gScratchBuffer;

	// Clear the scratch buffer.
	RefPtr<cairo_t> scratchBufferContext = adoptRef(gdk_cairo_create(gScratchBuffer));
	cairo_set_operator(scratchBufferContext.get(), CAIRO_OPERATOR_CLEAR);
	cairo_paint(scratchBufferContext.get());
	}

	WidgetRenderingContext::~WidgetRenderingContext()
	{
	// We do not need to blit back to the target in the fallback case. See above.
	RenderThemeGtk* theme = static_cast<RenderThemeGtk*>(RenderTheme::defaultTheme().get());
	if (!theme->m_themePartsHaveRGBAColormap && m_graphicsContext->gdkWindow())
	return;

	// Don't paint the results back if there was an error.
	if (m_hadError) {
	scheduleScratchBufferPurge();
	return;
	}

	// FIXME: It's unclear if it is necessary to preserve the current source here.
	cairo_t* cairoContext = m_graphicsContext->platformContext()->cr();
	RefPtr<cairo_pattern_t> previousSource(cairo_get_source(cairoContext));

	gdk_cairo_set_source_pixmap(cairoContext, gScratchBuffer, m_targetRect.x(), m_targetRect.y());
	cairo_rectangle(cairoContext, m_targetRect.x(), m_targetRect.y(), m_targetRect.width(), m_targetRect.height());
	cairo_fill(cairoContext);
	cairo_set_source(cairoContext, previousSource.get());
	scheduleScratchBufferPurge();
	}

	void WidgetRenderingContext::calculateClipRect(const IntRect& rect, GdkRectangle* clipRect)
	{
	clipRect->x = m_paintOffset.width() + rect.x();
	clipRect->y = m_paintOffset.height() + rect.y();
	clipRect->width = m_targetRect.width();
	clipRect->height = m_targetRect.height();
	}

	void WidgetRenderingContext::gtkPaintBox(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail)
	{
	GdkRectangle clipRect;
	calculateClipRect(rect, &clipRect);

	// Some widgets also need their allocation adjusted to account for extra space.
	// Right now only scrollbar buttons have significant allocations.
	GtkAllocation allocation;
	gtk_widget_get_allocation(widget, &allocation);
	allocation.x += clipRect.x;
	allocation.y += clipRect.y;
	gtk_widget_set_allocation(widget, &allocation);

	gtk_paint_box(gtk_widget_get_style(widget), m_target, stateType, shadowType, &clipRect,
	widget, detail, clipRect.x, clipRect.y, rect.width(), rect.height());
	}

	void WidgetRenderingContext::gtkPaintFlatBox(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail)
	{
	GdkRectangle clipRect;
	calculateClipRect(rect, &clipRect);
	gtk_paint_flat_box(gtk_widget_get_style(widget), m_target, stateType, shadowType, &clipRect,
	widget, detail, clipRect.x, clipRect.y, rect.width(), rect.height());
	}

	void WidgetRenderingContext::gtkPaintFocus(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, const gchar* detail)
	{
	GdkRectangle clipRect;
	calculateClipRect(rect, &clipRect);
	gtk_paint_focus(gtk_widget_get_style(widget), m_target, stateType, &clipRect, widget,
	detail, clipRect.x, clipRect.y, rect.width(), rect.height());
	}

	void WidgetRenderingContext::gtkPaintSlider(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail, GtkOrientation orientation)
	{
	GdkRectangle clipRect;
	calculateClipRect(rect, &clipRect);
	gtk_paint_slider(gtk_widget_get_style(widget), m_target, stateType, shadowType, &clipRect, widget,
	detail, clipRect.x, clipRect.y, rect.width(), rect.height(), orientation);
	}

	void WidgetRenderingContext::gtkPaintCheck(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail)
	{
	GdkRectangle clipRect;
	calculateClipRect(rect, &clipRect);
	gtk_paint_check(gtk_widget_get_style(widget), m_target, stateType, shadowType, &clipRect, widget,
	detail, clipRect.x, clipRect.y, rect.width(), rect.height());
	}

	void WidgetRenderingContext::gtkPaintOption(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail)
	{
	GdkRectangle clipRect;
	calculateClipRect(rect, &clipRect);
	gtk_paint_option(gtk_widget_get_style(widget), m_target, stateType, shadowType, &clipRect, widget,
	detail, clipRect.x, clipRect.y, rect.width(), rect.height());
	}

	void WidgetRenderingContext::gtkPaintShadow(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail)
	{
	GdkRectangle clipRect;
	calculateClipRect(rect, &clipRect);
	gtk_paint_shadow(gtk_widget_get_style(widget), m_target, stateType, shadowType, &clipRect, widget,
	detail, clipRect.x, clipRect.y, rect.width(), rect.height());
	}

	void WidgetRenderingContext::gtkPaintArrow(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, int arrowDirection, const gchar* detail)
	{
	GdkRectangle clipRect;
	calculateClipRect(rect, &clipRect);
	gtk_paint_arrow(gtk_widget_get_style(widget), m_target, stateType, shadowType, &clipRect, widget, detail,
	static_cast<GtkArrowType>(arrowDirection), TRUE, clipRect.x, clipRect.y, rect.width(), rect.height());
	}

	void WidgetRenderingContext::gtkPaintVLine(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, const gchar* detail)
	{
	GdkRectangle clipRect;
	calculateClipRect(rect, &clipRect);
	gtk_paint_vline(gtk_widget_get_style(widget), m_target, stateType, &clipRect, widget, detail,
	clipRect.y, clipRect.y + rect.height(), clipRect.x);

	}

	}

	#endif // GTK_API_VERSION_2