gtk2/gtk/gtkthemingbackground.c
Cosimo Cecchi a7f3a9ff74 themingengine: split a GtkThemingBackground object
Allows easier modification and general sanity of the CSS background
rendering code.
2011-12-12 12:46:52 +01:00

439 lines
15 KiB
C

/* GTK - The GIMP Toolkit
* Copyright (C) 2010 Carlos Garnacho <carlosg@gnome.org>
* Copyright (C) 2011 Red Hat, Inc.
*
* Authors: Carlos Garnacho <carlosg@gnome.org>
* Cosimo Cecchi <cosimoc@gnome.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include "gtkcsstypesprivate.h"
#include "gtkthemingbackgroundprivate.h"
#include "gtkthemingengineprivate.h"
#include <gdk/gdk.h>
static void
_gtk_theming_background_apply_window_background (GtkThemingBackground *bg,
cairo_t *cr)
{
if (gtk_theming_engine_has_class (bg->engine, "background"))
{
cairo_set_source_rgba (cr, 1.0, 1.0, 1.0, 0.0); /* transparent */
cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
cairo_paint (cr);
}
}
static void
_gtk_theming_background_apply_running_transformation (GtkThemingBackground *bg,
cairo_t *cr)
{
gboolean running;
gdouble progress;
cairo_pattern_t *other_pattern;
GtkStateFlags other_flags;
GdkRGBA other_bg;
cairo_pattern_t *new_pattern = NULL;
running = gtk_theming_engine_state_is_running (bg->engine, GTK_STATE_PRELIGHT, &progress);
if (!running)
return;
if (bg->flags & GTK_STATE_FLAG_PRELIGHT)
{
other_flags = bg->flags & ~(GTK_STATE_FLAG_PRELIGHT);
progress = 1 - progress;
}
else
other_flags = bg->flags | GTK_STATE_FLAG_PRELIGHT;
gtk_theming_engine_get_background_color (bg->engine, other_flags, &other_bg);
_gtk_theming_engine_get (bg->engine, other_flags, &bg->prop_context,
"background-image", &other_pattern,
NULL);
if (bg->pattern && other_pattern)
{
cairo_pattern_type_t type, other_type;
gint n0, n1;
cairo_pattern_get_color_stop_count (bg->pattern, &n0);
cairo_pattern_get_color_stop_count (other_pattern, &n1);
type = cairo_pattern_get_type (bg->pattern);
other_type = cairo_pattern_get_type (other_pattern);
if (type == other_type && n0 == n1)
{
gdouble offset0, red0, green0, blue0, alpha0;
gdouble offset1, red1, green1, blue1, alpha1;
gdouble x00, x01, y00, y01, x10, x11, y10, y11;
gdouble r00, r01, r10, r11;
guint i;
if (type == CAIRO_PATTERN_TYPE_LINEAR)
{
cairo_pattern_get_linear_points (bg->pattern, &x00, &y00, &x01, &y01);
cairo_pattern_get_linear_points (other_pattern, &x10, &y10, &x11, &y11);
new_pattern = cairo_pattern_create_linear (x00 + (x10 - x00) * progress,
y00 + (y10 - y00) * progress,
x01 + (x11 - x01) * progress,
y01 + (y11 - y01) * progress);
}
else
{
cairo_pattern_get_radial_circles (bg->pattern, &x00, &y00, &r00, &x01, &y01, &r01);
cairo_pattern_get_radial_circles (other_pattern, &x10, &y10, &r10, &x11, &y11, &r11);
new_pattern = cairo_pattern_create_radial (x00 + (x10 - x00) * progress,
y00 + (y10 - y00) * progress,
r00 + (r10 - r00) * progress,
x01 + (x11 - x01) * progress,
y01 + (y11 - y01) * progress,
r01 + (r11 - r01) * progress);
}
cairo_pattern_set_filter (new_pattern, CAIRO_FILTER_FAST);
i = 0;
/* Blend both gradients into one */
while (i < n0 && i < n1)
{
cairo_pattern_get_color_stop_rgba (bg->pattern, i,
&offset0,
&red0, &green0, &blue0,
&alpha0);
cairo_pattern_get_color_stop_rgba (other_pattern, i,
&offset1,
&red1, &green1, &blue1,
&alpha1);
cairo_pattern_add_color_stop_rgba (new_pattern,
offset0 + ((offset1 - offset0) * progress),
red0 + ((red1 - red0) * progress),
green0 + ((green1 - green0) * progress),
blue0 + ((blue1 - blue0) * progress),
alpha0 + ((alpha1 - alpha0) * progress));
i++;
}
}
else
{
cairo_save (cr);
cairo_rectangle (cr, 0, 0, bg->paint_area.width, bg->paint_area.height);
cairo_clip (cr);
cairo_push_group (cr);
cairo_scale (cr, bg->paint_area.width, bg->paint_area.height);
cairo_set_source (cr, other_pattern);
cairo_paint_with_alpha (cr, progress);
cairo_set_source (cr, bg->pattern);
cairo_paint_with_alpha (cr, 1.0 - progress);
new_pattern = cairo_pop_group (cr);
cairo_restore (cr);
}
}
else if (bg->pattern || other_pattern)
{
cairo_pattern_t *p;
const GdkRGBA *c;
gdouble x0, y0, x1, y1, r0, r1;
gint n, i;
/* Blend a pattern with a color */
if (bg->pattern)
{
p = bg->pattern;
c = &other_bg;
progress = 1 - progress;
}
else
{
p = other_pattern;
c = &bg->bg_color;
}
if (cairo_pattern_get_type (p) == CAIRO_PATTERN_TYPE_LINEAR)
{
cairo_pattern_get_linear_points (p, &x0, &y0, &x1, &y1);
new_pattern = cairo_pattern_create_linear (x0, y0, x1, y1);
}
else
{
cairo_pattern_get_radial_circles (p, &x0, &y0, &r0, &x1, &y1, &r1);
new_pattern = cairo_pattern_create_radial (x0, y0, r0, x1, y1, r1);
}
cairo_pattern_get_color_stop_count (p, &n);
for (i = 0; i < n; i++)
{
gdouble red1, green1, blue1, alpha1;
gdouble offset;
cairo_pattern_get_color_stop_rgba (p, i,
&offset,
&red1, &green1, &blue1,
&alpha1);
cairo_pattern_add_color_stop_rgba (new_pattern, offset,
c->red + ((red1 - c->red) * progress),
c->green + ((green1 - c->green) * progress),
c->blue + ((blue1 - c->blue) * progress),
c->alpha + ((alpha1 - c->alpha) * progress));
}
}
else
{
/* Merge just colors */
new_pattern = cairo_pattern_create_rgba (CLAMP (bg->bg_color.red + ((other_bg.red - bg->bg_color.red) * progress), 0, 1),
CLAMP (bg->bg_color.green + ((other_bg.green - bg->bg_color.green) * progress), 0, 1),
CLAMP (bg->bg_color.blue + ((other_bg.blue - bg->bg_color.blue) * progress), 0, 1),
CLAMP (bg->bg_color.alpha + ((other_bg.alpha - bg->bg_color.alpha) * progress), 0, 1));
}
if (new_pattern)
{
/* Replace pattern to use */
cairo_pattern_destroy (bg->pattern);
bg->pattern = new_pattern;
}
if (other_pattern)
cairo_pattern_destroy (other_pattern);
}
static void
_gtk_theming_background_apply_origin (GtkThemingBackground *bg)
{
GtkCssArea origin;
cairo_rectangle_t image_rect;
gtk_theming_engine_get (bg->engine, bg->flags,
"background-origin", &origin,
NULL);
/* The default size of the background image depends on the
background-origin value as this affects the top left
and the bottom right corners. */
switch (origin) {
case GTK_CSS_AREA_BORDER_BOX:
image_rect.x = 0;
image_rect.y = 0;
image_rect.width = bg->paint_area.width;
image_rect.height = bg->paint_area.height;
break;
case GTK_CSS_AREA_CONTENT_BOX:
image_rect.x = bg->border.left + bg->padding.left;
image_rect.y = bg->border.top + bg->padding.top;
image_rect.width = bg->paint_area.width - bg->border.left - bg->border.right - bg->padding.left - bg->padding.right;
image_rect.height = bg->paint_area.height - bg->border.top - bg->border.bottom - bg->padding.top - bg->padding.bottom;
break;
case GTK_CSS_AREA_PADDING_BOX:
default:
image_rect.x = bg->border.left;
image_rect.y = bg->border.top;
image_rect.width = bg->paint_area.width - bg->border.left - bg->border.right;
image_rect.height = bg->paint_area.height - bg->border.top - bg->border.bottom;
break;
}
bg->image_rect = image_rect;
bg->prop_context.width = image_rect.width;
bg->prop_context.height = image_rect.height;
}
static void
_gtk_theming_background_apply_clip (GtkThemingBackground *bg)
{
GtkCssArea clip;
gtk_theming_engine_get (bg->engine, bg->flags,
"background-clip", &clip,
NULL);
if (clip == GTK_CSS_AREA_PADDING_BOX)
{
_gtk_rounded_box_shrink (&bg->clip_box,
bg->border.top, bg->border.right,
bg->border.bottom, bg->border.left);
}
else if (clip == GTK_CSS_AREA_CONTENT_BOX)
{
_gtk_rounded_box_shrink (&bg->clip_box,
bg->border.top + bg->padding.top,
bg->border.right + bg->padding.right,
bg->border.bottom + bg->padding.bottom,
bg->border.left + bg->padding.left);
}
}
static void
_gtk_theming_background_paint (GtkThemingBackground *bg,
cairo_t *cr)
{
_gtk_rounded_box_path (&bg->clip_box, cr);
gdk_cairo_set_source_rgba (cr, &bg->bg_color);
if (bg->pattern)
{
GtkCssBackgroundRepeat *repeat;
cairo_surface_t *surface;
int scale_width, scale_height;
gtk_theming_engine_get (bg->engine, bg->flags,
"background-repeat", &repeat,
NULL);
/* Fill background color first */
cairo_fill_preserve (cr);
if (cairo_pattern_get_surface (bg->pattern, &surface) != CAIRO_STATUS_SUCCESS)
surface = NULL;
if (surface && repeat &&
repeat->repeat != GTK_CSS_BACKGROUND_REPEAT_STYLE_NONE)
{
scale_width = cairo_image_surface_get_width (surface);
scale_height = cairo_image_surface_get_height (surface);
if (repeat->repeat == GTK_CSS_BACKGROUND_REPEAT_STYLE_REPEAT)
cairo_pattern_set_extend (bg->pattern, CAIRO_EXTEND_REPEAT);
else if (repeat->repeat == GTK_CSS_BACKGROUND_REPEAT_STYLE_NO_REPEAT)
cairo_pattern_set_extend (bg->pattern, CAIRO_EXTEND_NONE);
}
else
{
cairo_pattern_set_extend (bg->pattern, CAIRO_EXTEND_PAD);
scale_width = bg->image_rect.width;
scale_height = bg->image_rect.height;
}
cairo_translate (cr, bg->image_rect.x, bg->image_rect.y);
cairo_scale (cr, scale_width, scale_height);
cairo_set_source (cr, bg->pattern);
cairo_scale (cr, 1.0 / scale_width, 1.0 / scale_height);
cairo_translate (cr, -bg->image_rect.x, -bg->image_rect.y);
g_free (repeat);
cairo_pattern_destroy (bg->pattern);
bg->pattern = NULL;
}
cairo_fill (cr);
}
static void
_gtk_theming_background_apply_shadow (GtkThemingBackground *bg,
cairo_t *cr)
{
GtkShadow *box_shadow;
gtk_theming_engine_get (bg->engine, bg->flags,
"box-shadow", &box_shadow,
NULL);
if (box_shadow != NULL)
{
_gtk_box_shadow_render (box_shadow, cr, &bg->padding_box);
_gtk_shadow_unref (box_shadow);
}
}
static void
_gtk_theming_background_init_engine (GtkThemingBackground *bg)
{
bg->flags = gtk_theming_engine_get_state (bg->engine);
gtk_theming_engine_get_border (bg->engine, bg->flags, &bg->border);
gtk_theming_engine_get_padding (bg->engine, bg->flags, &bg->padding);
gtk_theming_engine_get_background_color (bg->engine, bg->flags, &bg->bg_color);
/* In the CSS box model, by default the background positioning area is
* the padding-box, i.e. all the border-box minus the borders themselves,
* which determines also its default size, see
* http://dev.w3.org/csswg/css3-background/#background-origin
*
* In the future we might want to support different origins or clips, but
* right now we just shrink to the default.
*/
_gtk_rounded_box_init_rect (&bg->padding_box, 0, 0, bg->paint_area.width, bg->paint_area.height);
_gtk_rounded_box_apply_border_radius (&bg->padding_box, bg->engine, bg->flags, bg->junction);
bg->clip_box = bg->padding_box;
_gtk_rounded_box_shrink (&bg->padding_box,
bg->border.top, bg->border.right,
bg->border.bottom, bg->border.left);
_gtk_theming_background_apply_clip (bg);
_gtk_theming_background_apply_origin (bg);
_gtk_theming_engine_get (bg->engine, bg->flags, &bg->prop_context,
"background-image", &bg->pattern,
NULL);
}
void
_gtk_theming_background_init (GtkThemingBackground *bg,
GtkThemingEngine *engine,
gdouble x,
gdouble y,
gdouble width,
gdouble height,
GtkJunctionSides junction)
{
g_assert (bg != NULL);
bg->engine = engine;
bg->paint_area.x = x;
bg->paint_area.y = y;
bg->paint_area.width = width;
bg->paint_area.height = height;
bg->pattern = NULL;
bg->junction = junction;
_gtk_theming_background_init_engine (bg);
}
void
_gtk_theming_background_render (GtkThemingBackground *bg,
cairo_t *cr)
{
cairo_save (cr);
cairo_translate (cr, bg->paint_area.x, bg->paint_area.y);
_gtk_theming_background_apply_window_background (bg, cr);
_gtk_theming_background_apply_running_transformation (bg, cr);
_gtk_theming_background_paint (bg, cr);
_gtk_theming_background_apply_shadow (bg, cr);
cairo_restore (cr);
}
gboolean
_gtk_theming_background_has_background_image (GtkThemingBackground *bg)
{
return (bg->pattern != NULL) ? TRUE : FALSE;
}