gtk/gsk/gskrendernode.c
Benjamin Otte 8b8dfcdfb4 rendernode: Change to gsk_render_node_get_preferred_depth()
Instead of just tracking preferred_high_depth(), track the actual depth
we'd like to have.
2023-06-18 14:26:18 +02:00

696 lines
19 KiB
C

/* GSK - The GTK Scene Kit
*
* Copyright 2016 Endless
*
* 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/>.
*/
/**
* GskRenderNode: (ref-func gsk_render_node_ref) (unref-func gsk_render_node_unref) (set-value-func gsk_value_set_render_node) (get-value-func gsk_value_get_render_node)
*
* `GskRenderNode` is the basic block in a scene graph to be
* rendered using [class@Gsk.Renderer].
*
* Each node has a parent, except the top-level node; each node may have
* children nodes.
*
* Each node has an associated drawing surface, which has the size of
* the rectangle set when creating it.
*
* Render nodes are meant to be transient; once they have been associated
* to a [class@Gsk.Renderer] it's safe to release any reference you have on
* them. All [class@Gsk.RenderNode]s are immutable, you can only specify their
* properties during construction.
*/
#include "config.h"
#include "gskrendernodeprivate.h"
#include "gskdebugprivate.h"
#include "gskrendererprivate.h"
#include "gskrendernodeparserprivate.h"
#include <graphene-gobject.h>
#include <math.h>
#include <gobject/gvaluecollector.h>
G_DEFINE_QUARK (gsk-serialization-error-quark, gsk_serialization_error)
#define GSK_RENDER_NODE_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GSK_TYPE_RENDER_NODE, GskRenderNodeClass))
static void
value_render_node_init (GValue *value)
{
value->data[0].v_pointer = NULL;
}
static void
value_render_node_free_value (GValue *value)
{
if (value->data[0].v_pointer != NULL)
gsk_render_node_unref (value->data[0].v_pointer);
}
static void
value_render_node_copy_value (const GValue *src,
GValue *dst)
{
if (src->data[0].v_pointer != NULL)
dst->data[0].v_pointer = gsk_render_node_ref (src->data[0].v_pointer);
else
dst->data[0].v_pointer = NULL;
}
static gpointer
value_render_node_peek_pointer (const GValue *value)
{
return value->data[0].v_pointer;
}
static char *
value_render_node_collect_value (GValue *value,
guint n_collect_values,
GTypeCValue *collect_values,
guint collect_flags)
{
GskRenderNode *node = collect_values[0].v_pointer;
if (node == NULL)
{
value->data[0].v_pointer = NULL;
return NULL;
}
if (node->parent_instance.g_class == NULL)
return g_strconcat ("invalid unclassed GskRenderNode pointer for "
"value type '",
G_VALUE_TYPE_NAME (value),
"'",
NULL);
value->data[0].v_pointer = gsk_render_node_ref (node);
return NULL;
}
static char *
value_render_node_lcopy_value (const GValue *value,
guint n_collect_values,
GTypeCValue *collect_values,
guint collect_flags)
{
GskRenderNode **node_p = collect_values[0].v_pointer;
if (node_p == NULL)
return g_strconcat ("value location for '",
G_VALUE_TYPE_NAME (value),
"' passed as NULL",
NULL);
if (value->data[0].v_pointer == NULL)
*node_p = NULL;
else if (collect_flags & G_VALUE_NOCOPY_CONTENTS)
*node_p = value->data[0].v_pointer;
else
*node_p = gsk_render_node_ref (value->data[0].v_pointer);
return NULL;
}
static void
gsk_render_node_finalize (GskRenderNode *self)
{
g_type_free_instance ((GTypeInstance *) self);
}
static void
gsk_render_node_real_draw (GskRenderNode *node,
cairo_t *cr)
{
}
static gboolean
gsk_render_node_real_can_diff (const GskRenderNode *node1,
const GskRenderNode *node2)
{
return TRUE;
}
static void
gsk_render_node_real_diff (GskRenderNode *node1,
GskRenderNode *node2,
cairo_region_t *region)
{
gsk_render_node_diff_impossible (node1, node2, region);
}
static void
gsk_render_node_class_init (GskRenderNodeClass *klass)
{
klass->node_type = GSK_NOT_A_RENDER_NODE;
klass->finalize = gsk_render_node_finalize;
klass->draw = gsk_render_node_real_draw;
klass->can_diff = gsk_render_node_real_can_diff;
klass->diff = gsk_render_node_real_diff;
}
static void
gsk_render_node_init (GskRenderNode *self)
{
g_atomic_ref_count_init (&self->ref_count);
}
GType
gsk_render_node_get_type (void)
{
static gsize render_node_type__volatile;
if (g_once_init_enter (&render_node_type__volatile))
{
static const GTypeFundamentalInfo finfo = {
(G_TYPE_FLAG_CLASSED |
G_TYPE_FLAG_INSTANTIATABLE |
G_TYPE_FLAG_DERIVABLE |
G_TYPE_FLAG_DEEP_DERIVABLE),
};
static const GTypeValueTable value_table = {
value_render_node_init,
value_render_node_free_value,
value_render_node_copy_value,
value_render_node_peek_pointer,
"p",
value_render_node_collect_value,
"p",
value_render_node_lcopy_value,
};
const GTypeInfo node_info = {
/* Class */
sizeof (GskRenderNodeClass),
(GBaseInitFunc) NULL,
(GBaseFinalizeFunc) NULL,
(GClassInitFunc) gsk_render_node_class_init,
(GClassFinalizeFunc) NULL,
NULL,
/* Instance */
sizeof (GskRenderNode),
0,
(GInstanceInitFunc) gsk_render_node_init,
/* GValue */
&value_table,
};
GType render_node_type =
g_type_register_fundamental (g_type_fundamental_next (),
g_intern_static_string ("GskRenderNode"),
&node_info, &finfo,
G_TYPE_FLAG_ABSTRACT);
g_once_init_leave (&render_node_type__volatile, render_node_type);
}
return render_node_type__volatile;
}
/*< private >
* gsk_render_node_type_register_static:
* @node_name: the name of the node
* @node_info: type information of the node
*
* Registers a new `GskRenderNode` type for the given @node_name using
* the type information in @node_info.
*
* Returns: the newly registered GType
*/
GType
gsk_render_node_type_register_static (const char *node_name,
gsize instance_size,
GClassInitFunc class_init)
{
GTypeInfo info;
info.class_size = sizeof (GskRenderNodeClass);
info.base_init = NULL;
info.base_finalize = NULL;
info.class_init = class_init;
info.class_finalize = NULL;
info.instance_size = instance_size;
info.n_preallocs = 0;
info.instance_init = NULL;
info.value_table = NULL;
return g_type_register_static (GSK_TYPE_RENDER_NODE, node_name, &info, 0);
}
/*< private >
* gsk_render_node_alloc:
* @node_type: the `GskRenderNode`Type to instantiate
*
* Instantiates a new `GskRenderNode` for the given @node_type.
*
* Returns: (transfer full) (type GskRenderNode): the newly created `GskRenderNode`
*/
gpointer
gsk_render_node_alloc (GskRenderNodeType node_type)
{
g_return_val_if_fail (node_type > GSK_NOT_A_RENDER_NODE, NULL);
g_return_val_if_fail (node_type < GSK_RENDER_NODE_TYPE_N_TYPES, NULL);
g_assert (gsk_render_node_types[node_type] != G_TYPE_INVALID);
return g_type_create_instance (gsk_render_node_types[node_type]);
}
/**
* gsk_render_node_ref:
* @node: a `GskRenderNode`
*
* Acquires a reference on the given `GskRenderNode`.
*
* Returns: (transfer full): the `GskRenderNode` with an additional reference
*/
GskRenderNode *
gsk_render_node_ref (GskRenderNode *node)
{
g_return_val_if_fail (GSK_IS_RENDER_NODE (node), NULL);
g_atomic_ref_count_inc (&node->ref_count);
return node;
}
/**
* gsk_render_node_unref:
* @node: (transfer full): a `GskRenderNode`
*
* Releases a reference on the given `GskRenderNode`.
*
* If the reference was the last, the resources associated to the @node are
* freed.
*/
void
gsk_render_node_unref (GskRenderNode *node)
{
g_return_if_fail (GSK_IS_RENDER_NODE (node));
if (g_atomic_ref_count_dec (&node->ref_count))
GSK_RENDER_NODE_GET_CLASS (node)->finalize (node);
}
/**
* gsk_render_node_get_node_type:
* @node: a `GskRenderNode`
*
* Returns the type of the @node.
*
* Returns: the type of the `GskRenderNode`
*/
GskRenderNodeType
gsk_render_node_get_node_type (const GskRenderNode *node)
{
g_return_val_if_fail (GSK_IS_RENDER_NODE (node), GSK_NOT_A_RENDER_NODE);
return GSK_RENDER_NODE_GET_CLASS (node)->node_type;
}
G_GNUC_PURE static inline
GskRenderNodeType
_gsk_render_node_get_node_type (const GskRenderNode *node)
{
return GSK_RENDER_NODE_GET_CLASS (node)->node_type;
}
/**
* gsk_render_node_get_bounds:
* @node: a `GskRenderNode`
* @bounds: (out caller-allocates): return location for the boundaries
*
* Retrieves the boundaries of the @node.
*
* The node will not draw outside of its boundaries.
*/
void
gsk_render_node_get_bounds (GskRenderNode *node,
graphene_rect_t *bounds)
{
g_return_if_fail (GSK_IS_RENDER_NODE (node));
g_return_if_fail (bounds != NULL);
graphene_rect_init_from_rect (bounds, &node->bounds);
}
/**
* gsk_render_node_draw:
* @node: a `GskRenderNode`
* @cr: cairo context to draw to
*
* Draw the contents of @node to the given cairo context.
*
* Typically, you'll use this function to implement fallback rendering
* of `GskRenderNode`s on an intermediate Cairo context, instead of using
* the drawing context associated to a [class@Gdk.Surface]'s rendering buffer.
*
* For advanced nodes that cannot be supported using Cairo, in particular
* for nodes doing 3D operations, this function may fail.
**/
void
gsk_render_node_draw (GskRenderNode *node,
cairo_t *cr)
{
g_return_if_fail (GSK_IS_RENDER_NODE (node));
g_return_if_fail (cr != NULL);
g_return_if_fail (cairo_status (cr) == CAIRO_STATUS_SUCCESS);
cairo_save (cr);
GSK_DEBUG (CAIRO, "Rendering node %s[%p]",
g_type_name_from_instance ((GTypeInstance *) node),
node);
GSK_RENDER_NODE_GET_CLASS (node)->draw (node, cr);
#ifdef G_ENABLE_DEBUG
if (GSK_DEBUG_CHECK (GEOMETRY))
{
cairo_set_operator (cr, CAIRO_OPERATOR_OVER);
cairo_rectangle (cr, node->bounds.origin.x - 1, node->bounds.origin.y - 1,
node->bounds.size.width + 2, node->bounds.size.height + 2);
cairo_set_line_width (cr, 2);
cairo_set_source_rgba (cr, 0, 0, 0, 0.5);
cairo_stroke (cr);
}
#endif
cairo_restore (cr);
if (cairo_status (cr))
{
g_warning ("drawing failure for render node %s: %s",
g_type_name_from_instance ((GTypeInstance *) node),
cairo_status_to_string (cairo_status (cr)));
}
}
/*
* gsk_render_node_can_diff:
* @node1: a `GskRenderNode`
* @node2: the `GskRenderNode` to compare with
*
* Checks if two render nodes can be expected to be compared via
* gsk_render_node_diff().
*
* The node diffing algorithm uses this function to match up similar
* nodes to compare when trying to minimize the resulting region.
*
* Nodes of different type always return %FALSE here.
*
* Returns: %TRUE if @node1 and @node2 can be expected to be compared
**/
gboolean
gsk_render_node_can_diff (const GskRenderNode *node1,
const GskRenderNode *node2)
{
if (node1 == node2)
return TRUE;
if (_gsk_render_node_get_node_type (node1) == _gsk_render_node_get_node_type (node2))
return GSK_RENDER_NODE_GET_CLASS (node1)->can_diff (node1, node2);
if (_gsk_render_node_get_node_type (node1) == GSK_CONTAINER_NODE ||
_gsk_render_node_get_node_type (node2) == GSK_CONTAINER_NODE)
return TRUE;
return FALSE;
}
static void
rectangle_init_from_graphene (cairo_rectangle_int_t *cairo,
const graphene_rect_t *graphene)
{
cairo->x = floorf (graphene->origin.x);
cairo->y = floorf (graphene->origin.y);
cairo->width = ceilf (graphene->origin.x + graphene->size.width) - cairo->x;
cairo->height = ceilf (graphene->origin.y + graphene->size.height) - cairo->y;
}
void
gsk_render_node_diff_impossible (GskRenderNode *node1,
GskRenderNode *node2,
cairo_region_t *region)
{
cairo_rectangle_int_t rect;
rectangle_init_from_graphene (&rect, &node1->bounds);
cairo_region_union_rectangle (region, &rect);
rectangle_init_from_graphene (&rect, &node2->bounds);
cairo_region_union_rectangle (region, &rect);
}
/**
* gsk_render_node_diff:
* @node1: a `GskRenderNode`
* @node2: the `GskRenderNode` to compare with
* @region: a `cairo_region_t` to add the differences to
*
* Compares @node1 and @node2 trying to compute the minimal region of changes.
*
* In the worst case, this is the union of the bounds of @node1 and @node2.
*
* This function is used to compute the area that needs to be redrawn when
* the previous contents were drawn by @node1 and the new contents should
* correspond to @node2. As such, it is important that this comparison is
* faster than the time it takes to actually do the redraw.
*
* Note that the passed in @region may already contain previous results from
* previous node comparisons, so this function call will only add to it.
**/
void
gsk_render_node_diff (GskRenderNode *node1,
GskRenderNode *node2,
cairo_region_t *region)
{
if (node1 == node2)
return;
if (_gsk_render_node_get_node_type (node1) == _gsk_render_node_get_node_type (node2))
GSK_RENDER_NODE_GET_CLASS (node1)->diff (node1, node2, region);
else if (_gsk_render_node_get_node_type (node1) == GSK_CONTAINER_NODE)
gsk_container_node_diff_with (node1, node2, region);
else if (_gsk_render_node_get_node_type (node2) == GSK_CONTAINER_NODE)
gsk_container_node_diff_with (node2, node1, region);
else
gsk_render_node_diff_impossible (node1, node2, region);
}
/**
* gsk_render_node_write_to_file:
* @node: a `GskRenderNode`
* @filename: (type filename): the file to save it to.
* @error: Return location for a potential error
*
* This function is equivalent to calling [method@Gsk.RenderNode.serialize]
* followed by [func@GLib.file_set_contents].
*
* See those two functions for details on the arguments.
*
* It is mostly intended for use inside a debugger to quickly dump a render
* node to a file for later inspection.
*
* Returns: %TRUE if saving was successful
**/
gboolean
gsk_render_node_write_to_file (GskRenderNode *node,
const char *filename,
GError **error)
{
GBytes *bytes;
gboolean result;
g_return_val_if_fail (GSK_IS_RENDER_NODE (node), FALSE);
g_return_val_if_fail (filename != NULL, FALSE);
g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
bytes = gsk_render_node_serialize (node);
result = g_file_set_contents (filename,
g_bytes_get_data (bytes, NULL),
g_bytes_get_size (bytes),
error);
g_bytes_unref (bytes);
return result;
}
/**
* gsk_render_node_deserialize:
* @bytes: the bytes containing the data
* @error_func: (nullable) (scope call): Callback on parsing errors
* @user_data: (closure error_func): user_data for @error_func
*
* Loads data previously created via [method@Gsk.RenderNode.serialize].
*
* For a discussion of the supported format, see that function.
*
* Returns: (nullable) (transfer full): a new `GskRenderNode`
*/
GskRenderNode *
gsk_render_node_deserialize (GBytes *bytes,
GskParseErrorFunc error_func,
gpointer user_data)
{
GskRenderNode *node = NULL;
node = gsk_render_node_deserialize_from_bytes (bytes, error_func, user_data);
return node;
}
/**
* gsk_value_set_render_node:
* @value: a [struct@GObject.Value] initialized with type `GSK_TYPE_RENDER_NODE`
* @node: a `GskRenderNode`
*
* Stores the given `GskRenderNode` inside `value`.
*
* The [struct@GObject.Value] will acquire a reference to the `node`.
*
* Since: 4.6
*/
void
gsk_value_set_render_node (GValue *value,
GskRenderNode *node)
{
GskRenderNode *old_node;
g_return_if_fail (G_VALUE_HOLDS (value, GSK_TYPE_RENDER_NODE));
old_node = value->data[0].v_pointer;
if (node != NULL)
{
g_return_if_fail (GSK_IS_RENDER_NODE (node));
value->data[0].v_pointer = gsk_render_node_ref (node);
}
else
{
value->data[0].v_pointer = NULL;
}
if (old_node != NULL)
gsk_render_node_unref (old_node);
}
/**
* gsk_value_take_render_node:
* @value: a [struct@GObject.Value] initialized with type `GSK_TYPE_RENDER_NODE`
* @node: (transfer full) (nullable): a `GskRenderNode`
*
* Stores the given `GskRenderNode` inside `value`.
*
* This function transfers the ownership of the `node` to the `GValue`.
*
* Since: 4.6
*/
void
gsk_value_take_render_node (GValue *value,
GskRenderNode *node)
{
GskRenderNode *old_node;
g_return_if_fail (G_VALUE_HOLDS (value, GSK_TYPE_RENDER_NODE));
old_node = value->data[0].v_pointer;
if (node != NULL)
{
g_return_if_fail (GSK_IS_RENDER_NODE (node));
value->data[0].v_pointer = node;
}
else
{
value->data[0].v_pointer = NULL;
}
if (old_node != NULL)
gsk_render_node_unref (old_node);
}
/**
* gsk_value_get_render_node:
* @value: a `GValue` initialized with type `GSK_TYPE_RENDER_NODE`
*
* Retrieves the `GskRenderNode` stored inside the given `value`.
*
* Returns: (transfer none) (nullable): a `GskRenderNode`
*
* Since: 4.6
*/
GskRenderNode *
gsk_value_get_render_node (const GValue *value)
{
g_return_val_if_fail (G_VALUE_HOLDS (value, GSK_TYPE_RENDER_NODE), NULL);
return value->data[0].v_pointer;
}
/**
* gsk_value_dup_render_node:
* @value: a [struct@GObject.Value] initialized with type `GSK_TYPE_RENDER_NODE`
*
* Retrieves the `GskRenderNode` stored inside the given `value`, and acquires
* a reference to it.
*
* Returns: (transfer full) (nullable): a `GskRenderNode`
*
* Since: 4.6
*/
GskRenderNode *
gsk_value_dup_render_node (const GValue *value)
{
g_return_val_if_fail (G_VALUE_HOLDS (value, GSK_TYPE_RENDER_NODE), NULL);
if (value->data[0].v_pointer == NULL)
return NULL;
return gsk_render_node_ref (value->data[0].v_pointer);
}
GdkMemoryDepth
gsk_render_node_get_preferred_depth (const GskRenderNode *node)
{
return node->preferred_depth;
}
/* Whether we need an offscreen to handle opacity correctly for this node.
* We don't if there is only one drawing node inside (could be child
* node, or grandchild, or...).
*
* For containers with multiple children, we can avoid the offscreen if
* the children are known not to overlap.
*/
gboolean
gsk_render_node_use_offscreen_for_opacity (const GskRenderNode *node)
{
return node->offscreen_for_opacity;
}