1/*
2 * Copyright (C) 2010 Sencha, Inc.
3 * Copyright (C) 2010 Igalia S.L.
4 *
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
17 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
20 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
21 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
23 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
24 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#ifdef GTK_API_VERSION_2
30
31#include "config.h"
32#include "WidgetRenderingContext.h"
33
34#include "GraphicsContext.h"
35#include "GtkVersioning.h"
36#include "PlatformContextCairo.h"
37#include "RefPtrCairo.h"
38#include "RenderThemeGtk.h"
39#include "Timer.h"
40#include <gdk/gdk.h>
41#include <gtk/gtk.h>
42
43namespace WebCore {
44
45static GdkPixmap* gScratchBuffer = 0;
46static void purgeScratchBuffer()
47{
48    if (gScratchBuffer)
49        g_object_unref(gScratchBuffer);
50    gScratchBuffer = 0;
51}
52
53// FIXME: Perhaps we can share some of this code with the ContextShadowCairo.
54// Widget rendering needs a scratch image as the buffer for the intermediate
55// render. Instead of creating and destroying the buffer for every operation,
56// we create a buffer which will be automatically purged via a timer.
57class PurgeScratchBufferTimer : public TimerBase {
58private:
59    virtual void fired() { purgeScratchBuffer(); }
60};
61static PurgeScratchBufferTimer purgeScratchBufferTimer;
62static void scheduleScratchBufferPurge()
63{
64    if (purgeScratchBufferTimer.isActive())
65        purgeScratchBufferTimer.stop();
66    purgeScratchBufferTimer.startOneShot(2);
67}
68
69WidgetRenderingContext::WidgetRenderingContext(GraphicsContext* graphicsContext, const IntRect& targetRect)
70    : m_graphicsContext(graphicsContext)
71    , m_targetRect(targetRect)
72    , m_hadError(false)
73{
74    RenderThemeGtk* theme = static_cast<RenderThemeGtk*>(RenderTheme::defaultTheme().get());
75
76    // Fallback: We failed to create an RGBA colormap earlier, so we cannot properly paint
77    // to a temporary surface and preserve transparency. To ensure decent widget rendering, just
78    // paint directly to the target drawable. This will not render CSS rotational transforms properly.
79    if (!theme->m_themePartsHaveRGBAColormap && graphicsContext->gdkWindow()) {
80        m_paintRect = graphicsContext->getCTM().mapRect(targetRect);
81        m_target = graphicsContext->gdkWindow();
82        return;
83    }
84
85    // Widgets sometimes need to draw outside their boundaries for things such as
86    // exterior focus. We want to allocate a some extra pixels in our surface for this.
87    m_extraSpace = IntSize(15, 15);
88
89    // Offset the target rectangle so that the extra space is within the boundaries of the scratch buffer.
90    m_paintRect = IntRect(IntPoint(m_extraSpace.width(), m_extraSpace.height()),
91                                   m_targetRect.size());
92
93    int width = m_targetRect.width() + (m_extraSpace.width() * 2);
94    int height = m_targetRect.height() + (m_extraSpace.height() * 2);
95    int scratchWidth = 0;
96    int scratchHeight = 0;
97    if (gScratchBuffer)
98        gdk_pixmap_get_size(gScratchBuffer, &scratchWidth, &scratchHeight);
99
100    // We do not need to recreate the buffer if the current buffer is large enough.
101    if (!gScratchBuffer || scratchWidth < width || scratchHeight < height) {
102        purgeScratchBuffer();
103        // Round to the nearest 32 pixels so we do not grow the buffer for similar sized requests.
104        width = (1 + (width >> 5)) << 5;
105        height = (1 + (height >> 5)) << 5;
106
107        gScratchBuffer = gdk_pixmap_new(0, width, height, gdk_colormap_get_visual(theme->m_colormap)->depth);
108        gdk_drawable_set_colormap(gScratchBuffer, theme->m_colormap);
109    }
110    m_target = gScratchBuffer;
111
112    // Clear the scratch buffer.
113    RefPtr<cairo_t> scratchBufferContext = adoptRef(gdk_cairo_create(gScratchBuffer));
114    cairo_set_operator(scratchBufferContext.get(), CAIRO_OPERATOR_CLEAR);
115    cairo_paint(scratchBufferContext.get());
116}
117
118WidgetRenderingContext::~WidgetRenderingContext()
119{
120    // We do not need to blit back to the target in the fallback case. See above.
121    RenderThemeGtk* theme = static_cast<RenderThemeGtk*>(RenderTheme::defaultTheme().get());
122    if (!theme->m_themePartsHaveRGBAColormap && m_graphicsContext->gdkWindow())
123        return;
124
125    // Don't paint the results back if there was an error.
126    if (m_hadError) {
127        scheduleScratchBufferPurge();
128        return;
129    }
130
131    // FIXME: It's unclear if it is necessary to preserve the current source here.
132    cairo_t* cairoContext = m_graphicsContext->platformContext()->cr();
133    RefPtr<cairo_pattern_t> previousSource(cairo_get_source(cairoContext));
134
135    // The blit rectangle is the original target rectangle adjusted for any extra space.
136    IntRect fullTargetRect(m_targetRect);
137    fullTargetRect.inflateX(m_extraSpace.width());
138    fullTargetRect.inflateY(m_extraSpace.height());
139
140    gdk_cairo_set_source_pixmap(cairoContext, gScratchBuffer, fullTargetRect.x(), fullTargetRect.y());
141    cairo_rectangle(cairoContext, fullTargetRect.x(), fullTargetRect.y(), fullTargetRect.width(), fullTargetRect.height());
142    cairo_fill(cairoContext);
143    cairo_set_source(cairoContext, previousSource.get());
144    scheduleScratchBufferPurge();
145}
146
147void WidgetRenderingContext::gtkPaintBox(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail)
148{
149    GdkRectangle paintRect = { m_paintRect.x + rect.x(), m_paintRect.y + rect.y(), rect.width(), rect.height() };
150
151    // Some widgets also need their allocation adjusted to account for extra space.
152    // Right now only scrollbar buttons have significant allocations.
153    GtkAllocation allocation;
154    gtk_widget_get_allocation(widget, &allocation);
155    allocation.x += m_paintRect.x;
156    allocation.y += m_paintRect.y;
157    gtk_widget_set_allocation(widget, &allocation);
158
159    gtk_paint_box(gtk_widget_get_style(widget), m_target, stateType, shadowType, &paintRect,
160                  widget, detail, paintRect.x, paintRect.y, paintRect.width, paintRect.height);
161}
162
163void WidgetRenderingContext::gtkPaintFlatBox(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail)
164{
165    GdkRectangle paintRect = { m_paintRect.x + rect.x(), m_paintRect.y + rect.y(), rect.width(), rect.height() };
166    gtk_paint_flat_box(gtk_widget_get_style(widget), m_target, stateType, shadowType, &paintRect,
167                       widget, detail, paintRect.x, paintRect.y, paintRect.width, paintRect.height);
168}
169
170void WidgetRenderingContext::gtkPaintFocus(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, const gchar* detail)
171{
172    GdkRectangle paintRect = { m_paintRect.x + rect.x(), m_paintRect.y + rect.y(), rect.width(), rect.height() };
173    gtk_paint_focus(gtk_widget_get_style(widget), m_target, stateType, &paintRect, widget,
174                    detail, paintRect.x, paintRect.y, paintRect.width, paintRect.height);
175}
176
177void WidgetRenderingContext::gtkPaintSlider(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail, GtkOrientation orientation)
178{
179    GdkRectangle paintRect = { m_paintRect.x + rect.x(), m_paintRect.y + rect.y(), rect.width(), rect.height() };
180    gtk_paint_slider(gtk_widget_get_style(widget), m_target, stateType, shadowType, &m_paintRect, widget,
181                     detail, paintRect.x, paintRect.y, paintRect.width, paintRect.height, orientation);
182}
183
184void WidgetRenderingContext::gtkPaintCheck(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail)
185{
186    GdkRectangle paintRect = { m_paintRect.x + rect.x(), m_paintRect.y + rect.y(), rect.width(), rect.height() };
187    gtk_paint_check(gtk_widget_get_style(widget), m_target, stateType, shadowType, &paintRect, widget,
188                    detail, paintRect.x, paintRect.y, paintRect.width, paintRect.height);
189}
190
191void WidgetRenderingContext::gtkPaintOption(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail)
192{
193    GdkRectangle paintRect = { m_paintRect.x + rect.x(), m_paintRect.y + rect.y(), rect.width(), rect.height() };
194    gtk_paint_option(gtk_widget_get_style(widget), m_target, stateType, shadowType, &paintRect, widget,
195                     detail, paintRect.x, paintRect.y, paintRect.width, paintRect.height);
196}
197
198void WidgetRenderingContext::gtkPaintShadow(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, const gchar* detail)
199{
200    GdkRectangle paintRect = { m_paintRect.x + rect.x(), m_paintRect.y + rect.y(), rect.width(), rect.height() };
201    gtk_paint_shadow(gtk_widget_get_style(widget), m_target, stateType, shadowType, &paintRect, widget,
202                     detail, paintRect.x, paintRect.y, paintRect.width, paintRect.height);
203}
204
205void WidgetRenderingContext::gtkPaintArrow(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, GtkShadowType shadowType, int arrowDirection, const gchar* detail)
206{
207    GdkRectangle paintRect = { m_paintRect.x + rect.x(), m_paintRect.y + rect.y(), rect.width(), rect.height() };
208    gtk_paint_arrow(gtk_widget_get_style(widget), m_target, stateType, shadowType, &paintRect, widget, detail,
209                    static_cast<GtkArrowType>(arrowDirection), TRUE, paintRect.x, paintRect.y, paintRect.width, paintRect.height);
210}
211
212void WidgetRenderingContext::gtkPaintVLine(const IntRect& rect, GtkWidget* widget, GtkStateType stateType, const gchar* detail)
213{
214    GdkRectangle paintRect = { m_paintRect.x + rect.x(), m_paintRect.y + rect.y(), rect.width(), rect.height() };
215    gtk_paint_vline(gtk_widget_get_style(widget), m_target, stateType, &paintRect, widget, detail,
216                    paintRect.y, paintRect.y + paintRect.height, paintRect.x);
217
218}
219
220}
221
222#endif // GTK_API_VERSION_2
223