gtk2/gtk/gtkpixelcache.c
Alexander Larsson 2d0bdee075 pixel cache: Allow growing of cache surface
If the new requested surface size is enough larger than the previous
one (but the old is still larger than the absolute minimum),
reallocate it anyway.

This fixes an issue where the text view initially requested a really
small extra size which was then increased but that didn't "take".
2013-08-26 21:17:45 +02:00

427 lines
12 KiB
C

/* GTK - The GIMP Toolkit
* Copyright (C) 2013 Red Hat, Inc.
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include "config.h"
#include "gtkdebug.h"
#include "gtkpixelcacheprivate.h"
#define BLOW_CACHE_TIMEOUT_SEC 20
/* The extra size of the offscreen surface we allocate
to make scrolling more efficient */
#define DEFAULT_EXTRA_SIZE 64
/* When resizing viewport we allow this extra
size to avoid constantly reallocating when resizing */
#define ALLOW_SMALLER_SIZE 32
#define ALLOW_LARGER_SIZE 32
struct _GtkPixelCache {
cairo_surface_t *surface;
cairo_content_t content;
/* Valid if surface != NULL */
int surface_x;
int surface_y;
int surface_w;
int surface_h;
double surface_scale;
/* may be null if not dirty */
cairo_region_t *surface_dirty;
guint timeout_tag;
guint extra_width;
guint extra_height;
};
GtkPixelCache *
_gtk_pixel_cache_new ()
{
GtkPixelCache *cache;
cache = g_new0 (GtkPixelCache, 1);
cache->extra_width = DEFAULT_EXTRA_SIZE;
cache->extra_height = DEFAULT_EXTRA_SIZE;
return cache;
}
void
_gtk_pixel_cache_free (GtkPixelCache *cache)
{
if (cache == NULL)
return;
if (cache->timeout_tag)
g_source_remove (cache->timeout_tag);
if (cache->surface != NULL)
cairo_surface_destroy (cache->surface);
if (cache->surface_dirty != NULL)
cairo_region_destroy (cache->surface_dirty);
g_free (cache);
}
void
_gtk_pixel_cache_set_extra_size (GtkPixelCache *cache,
guint extra_width,
guint extra_height)
{
cache->extra_width = extra_width ? extra_width : DEFAULT_EXTRA_SIZE;
cache->extra_height = extra_height ? extra_height : DEFAULT_EXTRA_SIZE;
}
void
_gtk_pixel_cache_set_content (GtkPixelCache *cache,
cairo_content_t content)
{
cache->content = content;
_gtk_pixel_cache_invalidate (cache, NULL);
}
/* Region is in canvas coordinates */
void
_gtk_pixel_cache_invalidate (GtkPixelCache *cache,
cairo_region_t *region)
{
cairo_rectangle_int_t r;
cairo_region_t *free_region = NULL;
if (cache->surface == NULL ||
(region != NULL && cairo_region_is_empty (region)))
return;
if (region == NULL)
{
r.x = cache->surface_x;
r.y = cache->surface_y;
r.width = cache->surface_w;
r.height = cache->surface_h;
free_region = region =
cairo_region_create_rectangle (&r);
}
if (cache->surface_dirty == NULL)
{
cache->surface_dirty = cairo_region_copy (region);
cairo_region_translate (cache->surface_dirty,
-cache->surface_x,
-cache->surface_y);
}
else
{
cairo_region_translate (region,
-cache->surface_x,
-cache->surface_y);
cairo_region_union (cache->surface_dirty, region);
cairo_region_translate (region,
cache->surface_x,
cache->surface_y);
}
if (free_region)
cairo_region_destroy (free_region);
r.x = 0;
r.y = 0;
r.width = cache->surface_w;
r.height = cache->surface_h;
cairo_region_intersect_rectangle (cache->surface_dirty, &r);
}
static void
_gtk_pixel_cache_create_surface_if_needed (GtkPixelCache *cache,
GdkWindow *window,
cairo_rectangle_int_t *view_rect,
cairo_rectangle_int_t *canvas_rect)
{
cairo_rectangle_int_t rect;
int surface_w, surface_h;
cairo_content_t content;
cairo_pattern_t *bg;
double red, green, blue, alpha;
content = cache->content;
if (!content)
{
content = CAIRO_CONTENT_COLOR_ALPHA;
bg = gdk_window_get_background_pattern (window);
if (bg != NULL &&
cairo_pattern_get_type (bg) == CAIRO_PATTERN_TYPE_SOLID &&
cairo_pattern_get_rgba (bg, &red, &green, &blue, &alpha) == CAIRO_STATUS_SUCCESS &&
alpha == 1.0)
content = CAIRO_CONTENT_COLOR;
}
surface_w = view_rect->width;
if (canvas_rect->width > surface_w)
surface_w = MIN (surface_w + cache->extra_width, canvas_rect->width);
surface_h = view_rect->height;
if (canvas_rect->height > surface_h)
surface_h = MIN (surface_h + cache->extra_height, canvas_rect->height);
/* If current surface can't fit view_rect or is too large, kill it */
if (cache->surface != NULL &&
(cairo_surface_get_content (cache->surface) != content ||
cache->surface_w < MAX(view_rect->width, surface_w - ALLOW_SMALLER_SIZE) ||
cache->surface_w > surface_w + ALLOW_LARGER_SIZE ||
cache->surface_h < MAX(view_rect->height, surface_h - ALLOW_SMALLER_SIZE) ||
cache->surface_h > surface_h + ALLOW_LARGER_SIZE ||
cache->surface_scale != gdk_window_get_scale_factor (window)))
{
cairo_surface_destroy (cache->surface);
cache->surface = NULL;
if (cache->surface_dirty)
cairo_region_destroy (cache->surface_dirty);
cache->surface_dirty = NULL;
}
/* Don't allocate a surface if view >= canvas, as we won't
be scrolling then anyway */
if (cache->surface == NULL &&
(view_rect->width < canvas_rect->width ||
view_rect->height < canvas_rect->height))
{
cache->surface_x = -canvas_rect->x;
cache->surface_y = -canvas_rect->y;
cache->surface_w = surface_w;
cache->surface_h = surface_h;
cache->surface_scale = gdk_window_get_scale_factor (window);
cache->surface =
gdk_window_create_similar_surface (window, content,
surface_w, surface_h);
rect.x = 0;
rect.y = 0;
rect.width = surface_w;
rect.height = surface_h;
cache->surface_dirty =
cairo_region_create_rectangle (&rect);
}
}
void
_gtk_pixel_cache_set_position (GtkPixelCache *cache,
cairo_rectangle_int_t *view_rect,
cairo_rectangle_int_t *canvas_rect)
{
cairo_rectangle_int_t r, view_pos;
cairo_region_t *copy_region;
int new_surf_x, new_surf_y;
cairo_t *backing_cr;
if (cache->surface == NULL)
return;
/* Position of view inside canvas */
view_pos.x = -canvas_rect->x;
view_pos.y = -canvas_rect->y;
view_pos.width = view_rect->width;
view_pos.height = view_rect->height;
/* Reposition so all is visible */
if (view_pos.x < cache->surface_x ||
view_pos.x + view_pos.width >
cache->surface_x + cache->surface_w ||
view_pos.y < cache->surface_y ||
view_pos.y + view_pos.height >
cache->surface_y + cache->surface_h)
{
new_surf_x = cache->surface_x;
if (view_pos.x < cache->surface_x)
new_surf_x = MAX (view_pos.x + view_pos.width - cache->surface_w, 0);
else if (view_pos.x + view_pos.width >
cache->surface_x + cache->surface_w)
new_surf_x = MIN (view_pos.x, canvas_rect->width - cache->surface_w);
new_surf_y = cache->surface_y;
if (view_pos.y < cache->surface_y)
new_surf_y = MAX (view_pos.y + view_pos.height - cache->surface_h, 0);
else if (view_pos.y + view_pos.height >
cache->surface_y + cache->surface_h)
new_surf_y = MIN (view_pos.y, canvas_rect->height - cache->surface_h);
r.x = 0;
r.y = 0;
r.width = cache->surface_w;
r.height = cache->surface_h;
copy_region = cairo_region_create_rectangle (&r);
if (cache->surface_dirty)
{
cairo_region_subtract (copy_region, cache->surface_dirty);
cairo_region_destroy (cache->surface_dirty);
cache->surface_dirty = NULL;
}
cairo_region_translate (copy_region,
cache->surface_x - new_surf_x,
cache->surface_y - new_surf_y);
cairo_region_intersect_rectangle (copy_region, &r);
backing_cr = cairo_create (cache->surface);
gdk_cairo_region (backing_cr, copy_region);
cairo_set_operator (backing_cr, CAIRO_OPERATOR_SOURCE);
cairo_clip (backing_cr);
cairo_push_group (backing_cr);
cairo_set_source_surface (backing_cr, cache->surface,
cache->surface_x - new_surf_x,
cache->surface_y - new_surf_y);
cairo_paint (backing_cr);
cairo_pop_group_to_source (backing_cr);
cairo_paint (backing_cr);
cairo_destroy (backing_cr);
cache->surface_x = new_surf_x;
cache->surface_y = new_surf_y;
cairo_region_xor_rectangle (copy_region, &r);
cache->surface_dirty = copy_region;
}
}
void
_gtk_pixel_cache_repaint (GtkPixelCache *cache,
GtkPixelCacheDrawFunc draw,
cairo_rectangle_int_t *view_rect,
cairo_rectangle_int_t *canvas_rect,
gpointer user_data)
{
cairo_t *backing_cr;
if (cache->surface &&
cache->surface_dirty &&
!cairo_region_is_empty (cache->surface_dirty))
{
backing_cr = cairo_create (cache->surface);
gdk_cairo_region (backing_cr, cache->surface_dirty);
cairo_clip (backing_cr);
cairo_translate (backing_cr,
-cache->surface_x - canvas_rect->x - view_rect->x,
-cache->surface_y - canvas_rect->y - view_rect->y);
cairo_set_source_rgba (backing_cr,
0.0, 0, 0, 0.0);
cairo_set_operator (backing_cr, CAIRO_OPERATOR_SOURCE);
cairo_paint (backing_cr);
cairo_set_operator (backing_cr, CAIRO_OPERATOR_OVER);
cairo_save (backing_cr);
draw (backing_cr, user_data);
cairo_restore (backing_cr);
#ifdef G_ENABLE_DEBUG
if (gtk_get_debug_flags () & GTK_DEBUG_PIXEL_CACHE)
{
GdkRGBA colors[] = {
{ 1, 0, 0, 0.08},
{ 0, 1, 0, 0.08},
{ 0, 0, 1, 0.08},
{ 1, 0, 1, 0.08},
{ 1, 1, 0, 0.08},
{ 0, 1, 1, 0.08},
};
static int current_color = 0;
gdk_cairo_set_source_rgba (backing_cr, &colors[(current_color++) % G_N_ELEMENTS (colors)]);
cairo_paint (backing_cr);
}
#endif
cairo_destroy (backing_cr);
}
if (cache->surface_dirty)
{
cairo_region_destroy (cache->surface_dirty);
cache->surface_dirty = NULL;
}
}
static gboolean
blow_cache_cb (gpointer user_data)
{
GtkPixelCache *cache = user_data;
cache->timeout_tag = 0;
if (cache->surface)
{
cairo_surface_destroy (cache->surface);
cache->surface = NULL;
if (cache->surface_dirty)
cairo_region_destroy (cache->surface_dirty);
cache->surface_dirty = NULL;
}
return G_SOURCE_REMOVE;
}
void
_gtk_pixel_cache_draw (GtkPixelCache *cache,
cairo_t *cr,
GdkWindow *window,
/* View position in widget coords */
cairo_rectangle_int_t *view_rect,
/* Size and position of canvas in view coords */
cairo_rectangle_int_t *canvas_rect,
GtkPixelCacheDrawFunc draw,
gpointer user_data)
{
if (cache->timeout_tag)
g_source_remove (cache->timeout_tag);
cache->timeout_tag = g_timeout_add_seconds (BLOW_CACHE_TIMEOUT_SEC,
blow_cache_cb, cache);
_gtk_pixel_cache_create_surface_if_needed (cache, window,
view_rect, canvas_rect);
_gtk_pixel_cache_set_position (cache, view_rect, canvas_rect);
_gtk_pixel_cache_repaint (cache, draw, view_rect, canvas_rect, user_data);
if (cache->surface &&
/* Don't use backing surface if rendering elsewhere */
cairo_surface_get_type (cache->surface) == cairo_surface_get_type (cairo_get_target (cr)))
{
cairo_save (cr);
cairo_set_source_surface (cr, cache->surface,
cache->surface_x + view_rect->x + canvas_rect->x,
cache->surface_y + view_rect->y + canvas_rect->y);
cairo_rectangle (cr, view_rect->x, view_rect->y,
view_rect->width, view_rect->height);
cairo_fill (cr);
cairo_restore (cr);
}
else
{
cairo_rectangle (cr,
view_rect->x, view_rect->y,
view_rect->width, view_rect->height);
cairo_clip (cr);
draw (cr, user_data);
}
}