mutter/clutter/clutter-canvas.c
Emmanuele Bassi 857f53f42d canvas: Add scale-factor property
We need to provide an escape hatch to ClutterCanvas so that it's
possible to override the window-scaling-factor ClutterSetting. This is
going to be useful in the future in case the user has better knowledge
of the window scaling factor that is going to be used with a specific
set of ClutterCanvas contents (e.g. on different outputs or stages).

https://bugzilla.gnome.org/show_bug.cgi?id=705915
2014-01-20 12:26:46 +00:00

744 lines
20 KiB
C

/*
* Clutter.
*
* An OpenGL based 'interactive canvas' library.
*
* Copyright (C) 2012 Intel Corporation.
*
* 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/>.
*
* Author:
* Emmanuele Bassi <ebassi@linux.intel.com>
*/
/**
* SECTION:clutter-canvas
* @Title: ClutterCanvas
* @Short_Description: Content for 2D painting
* @See_Also: #ClutterContent
*
* The #ClutterCanvas class is a #ClutterContent implementation that allows
* drawing using the Cairo API on a 2D surface.
*
* In order to draw on a #ClutterCanvas, you should connect a handler to the
* #ClutterCanvas::draw signal; the signal will receive a #cairo_t context
* that can be used to draw. #ClutterCanvas will emit the #ClutterCanvas::draw
* signal when invalidated using clutter_content_invalidate().
*
* <informalexample id="canvas-example">
* <programlisting>
* <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" parse="text" href="../../../../examples/canvas.c">
* <xi:fallback>FIXME: MISSING XINCLUDE CONTENT</xi:fallback>
* </xi:include>
* </programlisting>
* </informalexample>
*
* #ClutterCanvas is available since Clutter 1.10.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <cogl/cogl.h>
#include <cairo-gobject.h>
#include "clutter-canvas.h"
#define CLUTTER_ENABLE_EXPERIMENTAL_API
#include "clutter-backend.h"
#include "clutter-cairo.h"
#include "clutter-color.h"
#include "clutter-content-private.h"
#include "clutter-debug.h"
#include "clutter-marshal.h"
#include "clutter-paint-node.h"
#include "clutter-paint-nodes.h"
#include "clutter-private.h"
#include "clutter-settings.h"
struct _ClutterCanvasPrivate
{
cairo_t *cr;
int width;
int height;
CoglBitmap *buffer;
int scale_factor;
guint scale_factor_set : 1;
};
enum
{
PROP_0,
PROP_WIDTH,
PROP_HEIGHT,
PROP_SCALE_FACTOR,
PROP_SCALE_FACTOR_SET,
LAST_PROP
};
static GParamSpec *obj_props[LAST_PROP] = { NULL, };
enum
{
DRAW,
LAST_SIGNAL
};
static guint canvas_signals[LAST_SIGNAL] = { 0, };
static void clutter_content_iface_init (ClutterContentIface *iface);
G_DEFINE_TYPE_WITH_CODE (ClutterCanvas, clutter_canvas, G_TYPE_OBJECT,
G_ADD_PRIVATE (ClutterCanvas)
G_IMPLEMENT_INTERFACE (CLUTTER_TYPE_CONTENT,
clutter_content_iface_init))
static void
clutter_cairo_context_draw_marshaller (GClosure *closure,
GValue *return_value,
guint n_param_values,
const GValue *param_values,
gpointer invocation_hint,
gpointer marshal_data)
{
cairo_t *cr = g_value_get_boxed (&param_values[1]);
cairo_save (cr);
_clutter_marshal_BOOLEAN__BOXED_INT_INT (closure,
return_value,
n_param_values,
param_values,
invocation_hint,
marshal_data);
cairo_restore (cr);
}
static void
clutter_canvas_finalize (GObject *gobject)
{
ClutterCanvasPrivate *priv = CLUTTER_CANVAS (gobject)->priv;
if (priv->buffer != NULL)
{
cogl_object_unref (priv->buffer);
priv->buffer = NULL;
}
G_OBJECT_CLASS (clutter_canvas_parent_class)->finalize (gobject);
}
static void
clutter_canvas_set_property (GObject *gobject,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
ClutterCanvasPrivate *priv = CLUTTER_CANVAS (gobject)->priv;
switch (prop_id)
{
case PROP_WIDTH:
{
gint new_size = g_value_get_int (value);
if (priv->width != new_size)
{
priv->width = new_size;
clutter_content_invalidate (CLUTTER_CONTENT (gobject));
}
}
break;
case PROP_HEIGHT:
{
gint new_size = g_value_get_int (value);
if (priv->height != new_size)
{
priv->height = new_size;
clutter_content_invalidate (CLUTTER_CONTENT (gobject));
}
}
break;
case PROP_SCALE_FACTOR:
clutter_canvas_set_scale_factor (CLUTTER_CANVAS (gobject),
g_value_get_int (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
break;
}
}
static void
clutter_canvas_get_property (GObject *gobject,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
ClutterCanvasPrivate *priv = CLUTTER_CANVAS (gobject)->priv;
switch (prop_id)
{
case PROP_WIDTH:
g_value_set_int (value, priv->width);
break;
case PROP_HEIGHT:
g_value_set_int (value, priv->height);
break;
case PROP_SCALE_FACTOR:
if (priv->scale_factor_set)
g_value_set_int (value, priv->scale_factor);
else
g_value_set_int (value, -1);
break;
case PROP_SCALE_FACTOR_SET:
g_value_set_boolean (value, priv->scale_factor_set);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
break;
}
}
static void
clutter_canvas_class_init (ClutterCanvasClass *klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
/**
* ClutterCanvas:width:
*
* The width of the canvas.
*
* Since: 1.10
*/
obj_props[PROP_WIDTH] =
g_param_spec_int ("width",
P_("Width"),
P_("The width of the canvas"),
-1, G_MAXINT,
-1,
G_PARAM_READWRITE |
G_PARAM_STATIC_STRINGS);
/**
* ClutterCanvas:height:
*
* The height of the canvas.
*
* Since: 1.10
*/
obj_props[PROP_HEIGHT] =
g_param_spec_int ("height",
P_("Height"),
P_("The height of the canvas"),
-1, G_MAXINT,
-1,
G_PARAM_READWRITE |
G_PARAM_STATIC_STRINGS);
/**
* ClutterCanvas:scale-factor-set:
*
* Whether the #ClutterCanvas:scale-factor property is set.
*
* If the #ClutterCanvas:scale-factor-set property is %FALSE
* then #ClutterCanvas will use the #ClutterSettings:window-scaling-factor
* property.
*
* Since: 1.18
*/
obj_props[PROP_SCALE_FACTOR_SET] =
g_param_spec_boolean ("scale-factor-set",
P_("Scale Factor Set"),
P_("Whether the scale-factor property is set"),
FALSE,
G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
/**
* ClutterCanvas:scale-factor:
*
* The scaling factor to be applied to the Cairo surface used for
* drawing.
*
* If #ClutterCanvas:scale-factor is set to a negative value, the
* value of the #ClutterSettings:window-scaling-factor property is
* used instead.
*
* Use #ClutterCanvas:scale-factor-set to check if the scale factor
* is set.
*
* Since: 1.18
*/
obj_props[PROP_SCALE_FACTOR] =
g_param_spec_int ("scale-factor",
P_("Scale Factor"),
P_("The scaling factor for the surface"),
-1, 1000,
-1,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
/**
* ClutterCanvas::draw:
* @canvas: the #ClutterCanvas that emitted the signal
* @cr: the Cairo context used to draw
* @width: the width of the @canvas
* @height: the height of the @canvas
*
* The #ClutterCanvas::draw signal is emitted each time a canvas is
* invalidated.
*
* It is safe to connect multiple handlers to this signal: each
* handler invocation will be automatically protected by cairo_save()
* and cairo_restore() pairs.
*
* Return value: %TRUE if the signal emission should stop, and
* %FALSE otherwise
*
* Since: 1.10
*/
canvas_signals[DRAW] =
g_signal_new (I_("draw"),
G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST | G_SIGNAL_NO_RECURSE,
G_STRUCT_OFFSET (ClutterCanvasClass, draw),
_clutter_boolean_handled_accumulator, NULL,
clutter_cairo_context_draw_marshaller,
G_TYPE_BOOLEAN, 3,
CAIRO_GOBJECT_TYPE_CONTEXT,
G_TYPE_INT,
G_TYPE_INT);
gobject_class->set_property = clutter_canvas_set_property;
gobject_class->get_property = clutter_canvas_get_property;
gobject_class->finalize = clutter_canvas_finalize;
g_object_class_install_properties (gobject_class, LAST_PROP, obj_props);
}
static void
clutter_canvas_init (ClutterCanvas *self)
{
self->priv = clutter_canvas_get_instance_private (self);
self->priv->width = -1;
self->priv->height = -1;
self->priv->scale_factor = -1;
}
static void
clutter_canvas_paint_content (ClutterContent *content,
ClutterActor *actor,
ClutterPaintNode *root)
{
ClutterCanvas *self = CLUTTER_CANVAS (content);
ClutterPaintNode *node;
CoglTexture *texture;
ClutterActorBox box;
ClutterColor color;
guint8 paint_opacity;
ClutterScalingFilter min_f, mag_f;
ClutterContentRepeat repeat;
if (self->priv->buffer == NULL)
return;
texture = cogl_texture_new_from_bitmap (self->priv->buffer,
COGL_TEXTURE_NO_SLICING,
CLUTTER_CAIRO_FORMAT_ARGB32);
if (texture == NULL)
return;
clutter_actor_get_content_box (actor, &box);
paint_opacity = clutter_actor_get_paint_opacity (actor);
clutter_actor_get_content_scaling_filters (actor, &min_f, &mag_f);
repeat = clutter_actor_get_content_repeat (actor);
color.red = paint_opacity;
color.green = paint_opacity;
color.blue = paint_opacity;
color.alpha = paint_opacity;
node = clutter_texture_node_new (texture, &color, min_f, mag_f);
cogl_object_unref (texture);
clutter_paint_node_set_name (node, "Canvas");
if (repeat == CLUTTER_REPEAT_NONE)
clutter_paint_node_add_rectangle (node, &box);
else
{
float t_w = 1.f, t_h = 1.f;
if ((repeat & CLUTTER_REPEAT_X_AXIS) != FALSE)
t_w = (box.x2 - box.x1) / cogl_texture_get_width (texture);
if ((repeat & CLUTTER_REPEAT_Y_AXIS) != FALSE)
t_h = (box.y2 - box.y1) / cogl_texture_get_height (texture);
clutter_paint_node_add_texture_rectangle (node, &box,
0.f, 0.f,
t_w, t_h);
}
clutter_paint_node_add_child (root, node);
clutter_paint_node_unref (node);
}
static void
clutter_canvas_emit_draw (ClutterCanvas *self)
{
ClutterCanvasPrivate *priv = self->priv;
int real_width, real_height;
cairo_surface_t *surface;
gboolean mapped_buffer;
unsigned char *data;
CoglBuffer *buffer;
int window_scale = 1;
gboolean res;
cairo_t *cr;
g_assert (priv->width > 0 && priv->width > 0);
if (priv->scale_factor_set)
window_scale = priv->scale_factor;
else
g_object_get (clutter_settings_get_default (),
"window-scaling-factor", &window_scale,
NULL);
real_width = priv->width * window_scale;
real_height = priv->height * window_scale;
CLUTTER_NOTE (MISC, "Creating Cairo surface with size %d x %d (real: %d x %d, scale: %d)",
priv->width, priv->height,
real_width, real_height,
window_scale);
if (priv->buffer == NULL)
{
CoglContext *ctx;
ctx = clutter_backend_get_cogl_context (clutter_get_default_backend ());
priv->buffer = cogl_bitmap_new_with_size (ctx,
real_width,
real_height,
CLUTTER_CAIRO_FORMAT_ARGB32);
}
buffer = COGL_BUFFER (cogl_bitmap_get_buffer (priv->buffer));
if (buffer == NULL)
return;
cogl_buffer_set_update_hint (buffer, COGL_BUFFER_UPDATE_HINT_DYNAMIC);
data = cogl_buffer_map (buffer,
COGL_BUFFER_ACCESS_READ_WRITE,
COGL_BUFFER_MAP_HINT_DISCARD);
if (data != NULL)
{
int bitmap_stride = cogl_bitmap_get_rowstride (priv->buffer);
surface = cairo_image_surface_create_for_data (data,
CAIRO_FORMAT_ARGB32,
real_width,
real_height,
bitmap_stride);
mapped_buffer = TRUE;
}
else
{
surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32,
real_width,
real_height);
mapped_buffer = FALSE;
}
#ifdef HAVE_CAIRO_SURFACE_SET_DEVICE_SCALE
cairo_surface_set_device_scale (surface, window_scale, window_scale);
#endif
self->priv->cr = cr = cairo_create (surface);
g_signal_emit (self, canvas_signals[DRAW], 0,
cr, priv->width, priv->height,
&res);
#ifdef CLUTTER_ENABLE_DEBUG
if (_clutter_diagnostic_enabled () && cairo_status (cr))
{
g_warning ("Drawing failed for <ClutterCanvas>[%p]: %s",
self,
cairo_status_to_string (cairo_status (cr)));
}
#endif
self->priv->cr = NULL;
cairo_destroy (cr);
if (mapped_buffer)
cogl_buffer_unmap (buffer);
else
{
int size = cairo_image_surface_get_stride (surface) * priv->height;
cogl_buffer_set_data (buffer,
0,
cairo_image_surface_get_data (surface),
size);
}
cairo_surface_destroy (surface);
}
static void
clutter_canvas_invalidate (ClutterContent *content)
{
ClutterCanvas *self = CLUTTER_CANVAS (content);
ClutterCanvasPrivate *priv = self->priv;
if (priv->buffer != NULL)
{
cogl_object_unref (priv->buffer);
priv->buffer = NULL;
}
if (priv->width <= 0 || priv->height <= 0)
return;
clutter_canvas_emit_draw (self);
}
static gboolean
clutter_canvas_get_preferred_size (ClutterContent *content,
gfloat *width,
gfloat *height)
{
ClutterCanvasPrivate *priv = CLUTTER_CANVAS (content)->priv;
if (priv->width < 0 || priv->height < 0)
return FALSE;
if (width != NULL)
*width = priv->width;
if (height != NULL)
*height = priv->height;
return TRUE;
}
static void
clutter_content_iface_init (ClutterContentIface *iface)
{
iface->invalidate = clutter_canvas_invalidate;
iface->paint_content = clutter_canvas_paint_content;
iface->get_preferred_size = clutter_canvas_get_preferred_size;
}
/**
* clutter_canvas_new:
*
* Creates a new instance of #ClutterCanvas.
*
* You should call clutter_canvas_set_size() to set the size of the canvas.
*
* You should call clutter_content_invalidate() every time you wish to
* draw the contents of the canvas.
*
* Return value: (transfer full): The newly allocated instance of
* #ClutterCanvas. Use g_object_unref() when done.
*
* Since: 1.10
*/
ClutterContent *
clutter_canvas_new (void)
{
return g_object_new (CLUTTER_TYPE_CANVAS, NULL);
}
static gboolean
clutter_canvas_invalidate_internal (ClutterCanvas *canvas,
int width,
int height)
{
gboolean width_changed = FALSE, height_changed = FALSE;
gboolean res = FALSE;
GObject *obj;
obj = G_OBJECT (canvas);
g_object_freeze_notify (obj);
if (canvas->priv->width != width)
{
canvas->priv->width = width;
width_changed = TRUE;
g_object_notify_by_pspec (obj, obj_props[PROP_WIDTH]);
}
if (canvas->priv->height != height)
{
canvas->priv->height = height;
height_changed = TRUE;
g_object_notify_by_pspec (obj, obj_props[PROP_HEIGHT]);
}
if (width_changed || height_changed)
{
clutter_content_invalidate (CLUTTER_CONTENT (canvas));
res = TRUE;
}
g_object_thaw_notify (obj);
return res;
}
/**
* clutter_canvas_set_size:
* @canvas: a #ClutterCanvas
* @width: the width of the canvas, in pixels
* @height: the height of the canvas, in pixels
*
* Sets the size of the @canvas, and invalidates the content.
*
* This function will cause the @canvas to be invalidated only
* if the size of the canvas surface has changed.
*
* If you want to invalidate the contents of the @canvas when setting
* the size, you can use the return value of the function to conditionally
* call clutter_content_invalidate():
*
* |[
* if (!clutter_canvas_set_size (canvas, width, height))
* clutter_content_invalidate (CLUTTER_CONTENT (canvas));
* ]|
*
* Return value: this function returns %TRUE if the size change
* caused a content invalidation, and %FALSE otherwise
*
* Since: 1.10
*/
gboolean
clutter_canvas_set_size (ClutterCanvas *canvas,
int width,
int height)
{
g_return_val_if_fail (CLUTTER_IS_CANVAS (canvas), FALSE);
g_return_val_if_fail (width >= -1 && height >= -1, FALSE);
return clutter_canvas_invalidate_internal (canvas, width, height);
}
/**
* clutter_canvas_set_scale_factor:
* @canvas: a #ClutterCanvas
* @scale: the scale factor, or -1 for the default
*
* Sets the scaling factor for the Cairo surface used by @canvas.
*
* This function should rarely be used.
*
* The default scaling factor of a #ClutterCanvas content uses the
* #ClutterSettings:window-scaling-factor property, which is set by
* the windowing system. By using this function it is possible to
* override that setting.
*
* Changing the scale factor will invalidate the @canvas.
*
* Since: 1.18
*/
void
clutter_canvas_set_scale_factor (ClutterCanvas *canvas,
int scale)
{
ClutterCanvasPrivate *priv;
GObject *obj;
g_return_if_fail (CLUTTER_IS_CANVAS (canvas));
g_return_if_fail (scale != 0);
priv = canvas->priv;
if (scale < 0)
{
if (!priv->scale_factor_set)
return;
priv->scale_factor_set = FALSE;
priv->scale_factor = -1;
}
else
{
if (priv->scale_factor_set && priv->scale_factor == scale)
return;
priv->scale_factor_set = TRUE;
priv->scale_factor = scale;
}
clutter_content_invalidate (CLUTTER_CONTENT (canvas));
obj = G_OBJECT (canvas);
g_object_notify_by_pspec (obj, obj_props[PROP_SCALE_FACTOR]);
g_object_notify_by_pspec (obj, obj_props[PROP_SCALE_FACTOR_SET]);
}
/**
* clutter_canvas_get_scale_factor:
* @canvas: a #ClutterCanvas
*
* Retrieves the scaling factor of @canvas, as set using
* clutter_canvas_set_scale_factor().
*
* Return value: the scaling factor, or -1 if the @canvas
* uses the default from #ClutterSettings
*
* Since: 1.18
*/
int
clutter_canvas_get_scale_factor (ClutterCanvas *canvas)
{
g_return_val_if_fail (CLUTTER_IS_CANVAS (canvas), -1);
if (!canvas->priv->scale_factor_set)
return -1;
return canvas->priv->scale_factor;
}