blob: 6d675ad45caba4d357ff803d815d3981ed392562 [file] [log] [blame]
// Copyright (c) 2009 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "gfx/canvas_skia.h"
#include <cairo/cairo.h>
#include <gtk/gtk.h>
#include <pango/pango.h>
#include <pango/pangocairo.h>
#include "base/logging.h"
#include "base/gtk_util.h"
#include "base/utf_string_conversions.h"
#include "gfx/font.h"
#include "gfx/gtk_util.h"
#include "gfx/platform_font_gtk.h"
#include "gfx/rect.h"
namespace {
const gunichar kAcceleratorChar = '&';
// Font settings that we initialize once and then use when drawing text in
// DrawStringInt().
static cairo_font_options_t* cairo_font_options = NULL;
// Update |cairo_font_options| based on GtkSettings, allocating it if needed.
static void UpdateCairoFontOptions() {
if (!cairo_font_options)
cairo_font_options = cairo_font_options_create();
GtkSettings* gtk_settings = gtk_settings_get_default();
gint antialias = 0;
gint hinting = 0;
gchar* hint_style = NULL;
gchar* rgba_style = NULL;
g_object_get(gtk_settings,
"gtk-xft-antialias", &antialias,
"gtk-xft-hinting", &hinting,
"gtk-xft-hintstyle", &hint_style,
"gtk-xft-rgba", &rgba_style,
NULL);
// g_object_get() doesn't tell us whether the properties were present or not,
// but if they aren't (because gnome-settings-daemon isn't running), we'll get
// NULL values for the strings.
if (hint_style && rgba_style) {
if (!antialias) {
cairo_font_options_set_antialias(cairo_font_options,
CAIRO_ANTIALIAS_NONE);
} else if (strcmp(rgba_style, "none") == 0) {
cairo_font_options_set_antialias(cairo_font_options,
CAIRO_ANTIALIAS_GRAY);
} else {
cairo_font_options_set_antialias(cairo_font_options,
CAIRO_ANTIALIAS_SUBPIXEL);
cairo_subpixel_order_t cairo_subpixel_order =
CAIRO_SUBPIXEL_ORDER_DEFAULT;
if (strcmp(rgba_style, "rgb") == 0) {
cairo_subpixel_order = CAIRO_SUBPIXEL_ORDER_RGB;
} else if (strcmp(rgba_style, "bgr") == 0) {
cairo_subpixel_order = CAIRO_SUBPIXEL_ORDER_BGR;
} else if (strcmp(rgba_style, "vrgb") == 0) {
cairo_subpixel_order = CAIRO_SUBPIXEL_ORDER_VRGB;
} else if (strcmp(rgba_style, "vbgr") == 0) {
cairo_subpixel_order = CAIRO_SUBPIXEL_ORDER_VBGR;
}
cairo_font_options_set_subpixel_order(cairo_font_options,
cairo_subpixel_order);
}
cairo_hint_style_t cairo_hint_style = CAIRO_HINT_STYLE_DEFAULT;
if (hinting == 0 || strcmp(hint_style, "hintnone") == 0) {
cairo_hint_style = CAIRO_HINT_STYLE_NONE;
} else if (strcmp(hint_style, "hintslight") == 0) {
cairo_hint_style = CAIRO_HINT_STYLE_SLIGHT;
} else if (strcmp(hint_style, "hintmedium") == 0) {
cairo_hint_style = CAIRO_HINT_STYLE_MEDIUM;
} else if (strcmp(hint_style, "hintfull") == 0) {
cairo_hint_style = CAIRO_HINT_STYLE_FULL;
}
cairo_font_options_set_hint_style(cairo_font_options, cairo_hint_style);
}
if (hint_style)
g_free(hint_style);
if (rgba_style)
g_free(rgba_style);
}
} // namespace
namespace gfx {
CanvasSkia::CanvasSkia(int width, int height, bool is_opaque)
: skia::PlatformCanvas(width, height, is_opaque) {
}
CanvasSkia::CanvasSkia() : skia::PlatformCanvas() {
}
CanvasSkia::~CanvasSkia() {
}
// Pass a width > 0 to force wrapping and elliding.
static void SetupPangoLayout(PangoLayout* layout,
const std::wstring& text,
const gfx::Font& font,
int width,
int flags) {
if (!cairo_font_options)
UpdateCairoFontOptions();
// This needs to be done early on; it has no effect when called just before
// pango_cairo_show_layout().
pango_cairo_context_set_font_options(
pango_layout_get_context(layout), cairo_font_options);
// Callers of DrawStringInt handle RTL layout themselves, so tell pango to not
// scope out RTL characters.
pango_layout_set_auto_dir(layout, FALSE);
if (width > 0)
pango_layout_set_width(layout, width * PANGO_SCALE);
if (flags & Canvas::NO_ELLIPSIS) {
pango_layout_set_ellipsize(layout, PANGO_ELLIPSIZE_NONE);
} else {
pango_layout_set_ellipsize(layout, PANGO_ELLIPSIZE_END);
}
if (flags & Canvas::TEXT_ALIGN_CENTER) {
pango_layout_set_alignment(layout, PANGO_ALIGN_CENTER);
} else if (flags & Canvas::TEXT_ALIGN_RIGHT) {
pango_layout_set_alignment(layout, PANGO_ALIGN_RIGHT);
}
if (flags & Canvas::MULTI_LINE) {
pango_layout_set_wrap(layout,
(flags & Canvas::CHARACTER_BREAK) ?
PANGO_WRAP_WORD_CHAR : PANGO_WRAP_WORD);
}
// Set the resolution to match that used by Gtk. If we don't set the
// resolution and the resolution differs from the default, Gtk and Chrome end
// up drawing at different sizes.
double resolution = gfx::GetPangoResolution();
if (resolution > 0) {
pango_cairo_context_set_resolution(pango_layout_get_context(layout),
resolution);
}
PangoFontDescription* desc = font.GetNativeFont();
pango_layout_set_font_description(layout, desc);
pango_font_description_free(desc);
// Set text and accelerator character if needed.
std::string utf8 = WideToUTF8(text);
if (flags & gfx::Canvas::SHOW_PREFIX) {
// Escape the text string to be used as markup.
gchar* escaped_text = g_markup_escape_text(utf8.c_str(), utf8.size());
pango_layout_set_markup_with_accel(layout,
escaped_text,
strlen(escaped_text),
kAcceleratorChar, NULL);
g_free(escaped_text);
} else if (flags & gfx::Canvas::HIDE_PREFIX) {
// Remove the ampersand character.
utf8 = gtk_util::RemoveWindowsStyleAccelerators(utf8);
pango_layout_set_text(layout, utf8.data(), utf8.size());
} else {
pango_layout_set_text(layout, utf8.data(), utf8.size());
}
}
// static
void CanvasSkia::SizeStringInt(const std::wstring& text,
const gfx::Font& font,
int* width, int* height,
int flags) {
int org_width = *width;
cairo_surface_t* surface =
cairo_image_surface_create(CAIRO_FORMAT_ARGB32, 0, 0);
cairo_t* cr = cairo_create(surface);
PangoLayout* layout = pango_cairo_create_layout(cr);
SetupPangoLayout(layout, text, font, *width, flags);
pango_layout_get_pixel_size(layout, width, height);
if (org_width > 0 && flags & Canvas::MULTI_LINE &&
pango_layout_is_wrapped(layout)) {
// The text wrapped. There seems to be a bug in Pango when this happens
// such that the width returned from pango_layout_get_pixel_size is too
// small. Using the width from pango_layout_get_pixel_size in this case
// results in wrapping across more lines, which requires a bigger height.
// As a workaround we use the original width, which is not necessarily
// exactly correct, but isn't wrong by much.
//
// It looks like Pango uses the size of whitespace in calculating wrapping
// but doesn't include the size of the whitespace when the extents are
// asked for. See the loop in pango-layout.c process_item that determines
// where to wrap.
*width = org_width;
}
g_object_unref(layout);
cairo_destroy(cr);
cairo_surface_destroy(surface);
}
void CanvasSkia::DrawStringInt(const std::wstring& text,
const gfx::Font& font,
const SkColor& color,
int x, int y, int w, int h,
int flags) {
if (w <= 0 || h <= 0)
return;
cairo_t* cr = beginPlatformPaint();
PangoLayout* layout = pango_cairo_create_layout(cr);
SetupPangoLayout(layout, text, font, w, flags);
pango_layout_set_height(layout, h * PANGO_SCALE);
cairo_save(cr);
cairo_set_source_rgba(cr,
SkColorGetR(color) / 255.0,
SkColorGetG(color) / 255.0,
SkColorGetB(color) / 255.0,
SkColorGetA(color) / 255.0);
int width, height;
pango_layout_get_pixel_size(layout, &width, &height);
cairo_rectangle(cr, x, y, w, h);
cairo_clip(cr);
if (flags & Canvas::TEXT_VALIGN_TOP) {
// Cairo should draw from the top left corner already.
} else if (flags & Canvas::TEXT_VALIGN_BOTTOM) {
y += (h - height);
} else {
// Vertically centered.
y += ((h - height) / 2);
}
cairo_move_to(cr, x, y);
pango_cairo_show_layout(cr, layout);
if (font.GetStyle() & gfx::Font::UNDERLINED) {
gfx::PlatformFontGtk* platform_font =
static_cast<gfx::PlatformFontGtk*>(font.platform_font());
double underline_y =
static_cast<double>(y) + height + platform_font->underline_position();
cairo_set_line_width(cr, platform_font->underline_thickness());
cairo_move_to(cr, x, underline_y);
cairo_line_to(cr, x + width, underline_y);
cairo_stroke(cr);
}
cairo_restore(cr);
g_object_unref(layout);
// NOTE: beginPlatformPaint returned its surface, we shouldn't destroy it.
}
void CanvasSkia::DrawGdkPixbuf(GdkPixbuf* pixbuf, int x, int y) {
if (!pixbuf) {
NOTREACHED();
return;
}
cairo_t* cr = beginPlatformPaint();
gdk_cairo_set_source_pixbuf(cr, pixbuf, x, y);
cairo_paint(cr);
}
} // namespace gfx