gtk/gsk/gskroundedrect.c
Benjamin Otte a6079b9b7b gsk: Implement gsk_render_node_diff()
This includes a copy of the diff(1) algorithm used by git diff by Davide
Libenzi.

It's used for the common case ofcontainer nodes having only very few
changes for the few nodes of child widgets that changed (like a button
lighting up when hilighted or a spinning spinner).
2018-04-05 14:56:38 +02:00

538 lines
18 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/>.
*/
/**
* SECTION:GskRoundedRect
* @Title: GskRoundedRect
* @Short_description: A rounded rectangle
*
* #GskRoundedRect defines a rectangle with rounded corners, as is commonly
* used in drawing.
*
* Operations on a #GskRoundedRect will normalize the rectangle, to
* ensure that the bounds are normalized and that the corner sizes don't exceed
* the size of the rectangle. The algorithm used for normalizing corner sizes
* is described in [the CSS specification](https://drafts.csswg.org/css-backgrounds-3/#border-radius).
*/
#include "config.h"
#include "gskroundedrect.h"
#include "gskroundedrectprivate.h"
#include "gskdebugprivate.h"
#include <math.h>
static void
gsk_rounded_rect_normalize_in_place (GskRoundedRect *self)
{
float factor = 1.0;
float corners;
guint i;
graphene_rect_normalize (&self->bounds);
for (i = 0; i < 4; i++)
{
self->corner[i].width = MAX (self->corner[i].width, 0);
self->corner[i].height = MAX (self->corner[i].height, 0);
}
/* clamp border radius, following CSS specs */
corners = self->corner[GSK_CORNER_TOP_LEFT].width + self->corner[GSK_CORNER_TOP_RIGHT].width;
if (corners > self->bounds.size.width)
factor = MIN (factor, self->bounds.size.width / corners);
corners = self->corner[GSK_CORNER_TOP_RIGHT].height + self->corner[GSK_CORNER_BOTTOM_RIGHT].height;
if (corners > self->bounds.size.height)
factor = MIN (factor, self->bounds.size.height / corners);
corners = self->corner[GSK_CORNER_BOTTOM_RIGHT].width + self->corner[GSK_CORNER_BOTTOM_LEFT].width;
if (corners > self->bounds.size.width)
factor = MIN (factor, self->bounds.size.width / corners);
corners = self->corner[GSK_CORNER_TOP_LEFT].height + self->corner[GSK_CORNER_BOTTOM_LEFT].height;
if (corners > self->bounds.size.height)
factor = MIN (factor, self->bounds.size.height / corners);
for (i = 0; i < 4; i++)
graphene_size_scale (&self->corner[i], factor, &self->corner[i]);
}
/**
* gsk_rounded_rect_init:
* @self: The #GskRoundedRect to initialize
* @bounds: a #graphene_rect_t describing the bounds
* @top_left: the rounding radius of the top left corner
* @top_right: the rounding radius of the top right corner
* @bottom_right: the rounding radius of the bottom right corner
* @bottom_left: the rounding radius of the bottom left corner
*
* Initializes the given #GskRoundedRect with the given values.
*
* This function will implicitly normalize the #GskRoundedRect
* before returning.
*
* Returns: (transfer none): the initialized rectangle
*/
GskRoundedRect *
gsk_rounded_rect_init (GskRoundedRect *self,
const graphene_rect_t *bounds,
const graphene_size_t *top_left,
const graphene_size_t *top_right,
const graphene_size_t *bottom_right,
const graphene_size_t *bottom_left)
{
graphene_rect_init_from_rect (&self->bounds, bounds);
graphene_size_init_from_size (&self->corner[GSK_CORNER_TOP_LEFT], top_left);
graphene_size_init_from_size (&self->corner[GSK_CORNER_TOP_RIGHT], top_right);
graphene_size_init_from_size (&self->corner[GSK_CORNER_BOTTOM_RIGHT], bottom_right);
graphene_size_init_from_size (&self->corner[GSK_CORNER_BOTTOM_LEFT], bottom_left);
gsk_rounded_rect_normalize_in_place (self);
return self;
}
/**
* gsk_rounded_rect_init_copy:
* @self: a #GskRoundedRect
* @src: a #GskRoundedRect
*
* Initializes @self using the given @src rectangle.
*
* This function will not normalize the #GskRoundedRect, so
* make sure the source is normalized.
*
* Returns: (transfer none): the initialized rectangle
*/
GskRoundedRect *
gsk_rounded_rect_init_copy (GskRoundedRect *self,
const GskRoundedRect *src)
{
*self = *src;
return self;
}
/**
* gsk_rounded_rect_init_from_rect:
* @self: a #GskRoundedRect
* @bounds: a #graphene_rect_t
* @radius: the border radius
*
* Initializes @self to the given @bounds and sets the radius of all
* four corners to @radius.
*
* Returns: (transfer none): the initialized rectangle
**/
GskRoundedRect *
gsk_rounded_rect_init_from_rect (GskRoundedRect *self,
const graphene_rect_t *bounds,
float radius)
{
graphene_size_t corner = GRAPHENE_SIZE_INIT(radius, radius);
return gsk_rounded_rect_init (self, bounds, &corner, &corner, &corner, &corner);
}
/**
* gsk_rounded_rect_normalize:
* @self: a #GskRoundedRect
*
* Normalizes the passed rectangle.
*
* this function will ensure that the bounds of the rectanlge are normalized
* and ensure that the corner values are positive and the corners do not overlap.
*
* Returns: (transfer none): the normalized rectangle
*/
GskRoundedRect *
gsk_rounded_rect_normalize (GskRoundedRect *self)
{
gsk_rounded_rect_normalize_in_place (self);
return self;
}
/**
* gsk_rounded_rect_offset:
* @self: a #GskRoundedRect
* @dx: the horizontal offset
* @dy: the vertical offset
*
* Offsets the bound's origin by @dx and @dy.
*
* The size and corners of the rectangle are unchanged.
*
* Returns: (transfer none): the offset rectangle
*/
GskRoundedRect *
gsk_rounded_rect_offset (GskRoundedRect *self,
float dx,
float dy)
{
gsk_rounded_rect_normalize (self);
self->bounds.origin.x += dx;
self->bounds.origin.y += dy;
return self;
}
static void
border_radius_shrink (graphene_size_t *corner,
double width,
double height)
{
if (corner->width > 0)
corner->width -= width;
if (corner->height > 0)
corner->height -= height;
if (corner->width <= 0 || corner->height <= 0)
{
corner->width = 0;
corner->height = 0;
}
}
/**
* gsk_rounded_rect_shrink:
* @self: The #GskRoundedRect to shrink or grow
* @top: How far to move the top side downwards
* @right: How far to move the right side to the left
* @bottom: How far to move the bottom side upwards
* @left: How far to move the left side to the right
*
* Shrinks (or grows) the given rectangle by moving the 4 sides
* according to the offsets given. The corner radii will be changed
* in a way that tries to keep the center of the corner circle intact.
* This emulates CSS behavior.
*
* This function also works for growing rectangles if you pass
* negative values for the @top, @right, @bottom or @left.
*
* Returns: (transfer none): the resized #GskRoundedRect
**/
GskRoundedRect *
gsk_rounded_rect_shrink (GskRoundedRect *self,
float top,
float right,
float bottom,
float left)
{
if (self->bounds.size.width - left - right < 0)
{
self->bounds.origin.x += left * self->bounds.size.width / (left + right);
self->bounds.size.width = 0;
}
else
{
self->bounds.origin.x += left;
self->bounds.size.width -= left + right;
}
if (self->bounds.size.height - bottom - top < 0)
{
self->bounds.origin.y += top * self->bounds.size.height / (top + bottom);
self->bounds.size.height = 0;
}
else
{
self->bounds.origin.y += top;
self->bounds.size.height -= top + bottom;
}
border_radius_shrink (&self->corner[GSK_CORNER_TOP_LEFT], left, top);
border_radius_shrink (&self->corner[GSK_CORNER_TOP_RIGHT], right, top);
border_radius_shrink (&self->corner[GSK_CORNER_BOTTOM_RIGHT], right, bottom);
border_radius_shrink (&self->corner[GSK_CORNER_BOTTOM_LEFT], left, bottom);
return self;
}
/* XXX: Find a better name */
gboolean
gsk_rounded_rect_is_circular (const GskRoundedRect *self)
{
guint i;
for (i = 0; i < 4; i++)
{
if (self->corner[i].width != self->corner[i].height)
return FALSE;
}
return TRUE;
}
/**
* gsk_rounded_rect_is_rectilinear:
* @self: the #GskRoundedRect to check
*
* Checks if all corners of @self are right angles and the
* rectangle covers all of its bounds.
*
* This information can be used to decide if gsk_clip_node_new()
* or gsk_rounded_clip_node_new() should be called.
*
* Returns: %TRUE if the rectangle is rectilinear
**/
gboolean
gsk_rounded_rect_is_rectilinear (const GskRoundedRect *self)
{
guint i;
for (i = 0; i < 4; i++)
{
if (self->corner[i].width > 0 ||
self->corner[i].height > 0)
return FALSE;
}
return TRUE;
}
static gboolean
ellipsis_contains_point (const graphene_size_t *ellipsis,
const graphene_point_t *point)
{
return (point->x * point->x) / (ellipsis->width * ellipsis->width)
+ (point->y * point->y) / (ellipsis->height * ellipsis->height) <= 1;
}
/**
* gsk_rounded_rect_contains_point:
* @self: a #GskRoundedRect
* @point: the point to check
*
* Checks if the given @point is inside the rounded rectangle. This function
* returns %FALSE if the point is in the rounded corner areas.
*
* Returns: %TRUE if the @point is inside the rounded rectangle
**/
gboolean
gsk_rounded_rect_contains_point (const GskRoundedRect *self,
const graphene_point_t *point)
{
if (!graphene_rect_contains_point (&self->bounds, point))
return FALSE;
if (self->bounds.origin.x + self->corner[GSK_CORNER_TOP_LEFT].width > point->x &&
self->bounds.origin.y + self->corner[GSK_CORNER_TOP_LEFT].height > point->y &&
!ellipsis_contains_point (&self->corner[GSK_CORNER_TOP_LEFT],
&GRAPHENE_POINT_INIT (
self->bounds.origin.x + self->corner[GSK_CORNER_TOP_LEFT].width - point->x,
self->bounds.origin.y + self->corner[GSK_CORNER_TOP_LEFT].height- point->y
)))
return FALSE;
if (self->bounds.origin.x + self->bounds.size.width - self->corner[GSK_CORNER_TOP_RIGHT].width < point->x &&
self->bounds.origin.y + self->corner[GSK_CORNER_TOP_RIGHT].height > point->y &&
!ellipsis_contains_point (&self->corner[GSK_CORNER_TOP_RIGHT],
&GRAPHENE_POINT_INIT (
self->bounds.origin.x + self->bounds.size.width - self->corner[GSK_CORNER_TOP_RIGHT].width - point->x,
self->bounds.origin.y + self->corner[GSK_CORNER_TOP_RIGHT].height- point->y
)))
return FALSE;
if (self->bounds.origin.x + self->corner[GSK_CORNER_BOTTOM_LEFT].width > point->x &&
self->bounds.origin.y + self->bounds.size.height - self->corner[GSK_CORNER_BOTTOM_LEFT].height < point->y &&
!ellipsis_contains_point (&self->corner[GSK_CORNER_BOTTOM_LEFT],
&GRAPHENE_POINT_INIT (
self->bounds.origin.x + self->corner[GSK_CORNER_BOTTOM_LEFT].width - point->x,
self->bounds.origin.y + self->bounds.size.height - self->corner[GSK_CORNER_BOTTOM_LEFT].height- point->y
)))
return FALSE;
if (self->bounds.origin.x + self->bounds.size.width - self->corner[GSK_CORNER_BOTTOM_RIGHT].width < point->x &&
self->bounds.origin.y + self->bounds.size.height - self->corner[GSK_CORNER_BOTTOM_RIGHT].height < point->y &&
!ellipsis_contains_point (&self->corner[GSK_CORNER_BOTTOM_RIGHT],
&GRAPHENE_POINT_INIT (
self->bounds.origin.x + self->bounds.size.width - self->corner[GSK_CORNER_BOTTOM_RIGHT].width - point->x,
self->bounds.origin.y + self->bounds.size.height - self->corner[GSK_CORNER_BOTTOM_RIGHT].height- point->y
)))
return FALSE;
return TRUE;
}
/**
* gsk_rounded_rect_contains_rect:
* @self: a #GskRoundedRect
* @rect: the rectangle to check
*
* Checks if the given @rect is contained inside the rounded rectangle.
* This function returns %FALSE if @rect extends into one of the rounded
* corner areas.
*
* Returns: %TRUE if the @rect is fully contained inside the rounded rectangle
**/
gboolean
gsk_rounded_rect_contains_rect (const GskRoundedRect *self,
const graphene_rect_t *rect)
{
if (!graphene_rect_contains_rect (&self->bounds, rect))
return FALSE;
if (!gsk_rounded_rect_contains_point (self, &rect->origin) ||
!gsk_rounded_rect_contains_point (self, &GRAPHENE_POINT_INIT (rect->origin.x + rect->size.width, rect->origin.y)) ||
!gsk_rounded_rect_contains_point (self, &GRAPHENE_POINT_INIT (rect->origin.x, rect->origin.y + rect->size.height)) ||
!gsk_rounded_rect_contains_point (self, &GRAPHENE_POINT_INIT (rect->origin.x + rect->size.width, rect->origin.y + rect->size.height)))
return FALSE;
return TRUE;
}
/**
* gsk_rounded_rect_intersects_rect:
* @self: a #GskRoundedRect
* @rect: the rectangle to check
*
* Checks if part of the given @rect is contained inside the rounded rectangle.
* This function returns %FALSE if @rect only extends into one of the rounded
* corner areas but not into the rounded rectangle itself.
*
* Returns: %TRUE if the @rect intersects with the rounded rectangle
**/
gboolean
gsk_rounded_rect_intersects_rect (const GskRoundedRect *self,
const graphene_rect_t *rect)
{
if (!graphene_rect_intersection (&self->bounds, rect, NULL))
return FALSE;
if (!gsk_rounded_rect_contains_point (self, &rect->origin) &&
!gsk_rounded_rect_contains_point (self, &GRAPHENE_POINT_INIT (rect->origin.x + rect->size.width, rect->origin.y)) &&
!gsk_rounded_rect_contains_point (self, &GRAPHENE_POINT_INIT (rect->origin.x, rect->origin.y + rect->size.height)) &&
!gsk_rounded_rect_contains_point (self, &GRAPHENE_POINT_INIT (rect->origin.x + rect->size.width, rect->origin.y + rect->size.height)))
return FALSE;
return TRUE;
}
static void
append_arc (cairo_t *cr, double angle1, double angle2, gboolean negative)
{
if (negative)
cairo_arc_negative (cr, 0.0, 0.0, 1.0, angle1, angle2);
else
cairo_arc (cr, 0.0, 0.0, 1.0, angle1, angle2);
}
static void
_cairo_ellipsis (cairo_t *cr,
double xc, double yc,
double xradius, double yradius,
double angle1, double angle2)
{
cairo_matrix_t save;
if (xradius <= 0.0 || yradius <= 0.0)
{
cairo_line_to (cr, xc, yc);
return;
}
cairo_get_matrix (cr, &save);
cairo_translate (cr, xc, yc);
cairo_scale (cr, xradius, yradius);
append_arc (cr, angle1, angle2, FALSE);
cairo_set_matrix (cr, &save);
}
void
gsk_rounded_rect_path (const GskRoundedRect *self,
cairo_t *cr)
{
cairo_new_sub_path (cr);
_cairo_ellipsis (cr,
self->bounds.origin.x + self->corner[GSK_CORNER_TOP_LEFT].width,
self->bounds.origin.y + self->corner[GSK_CORNER_TOP_LEFT].height,
self->corner[GSK_CORNER_TOP_LEFT].width,
self->corner[GSK_CORNER_TOP_LEFT].height,
G_PI, 3 * G_PI_2);
_cairo_ellipsis (cr,
self->bounds.origin.x + self->bounds.size.width - self->corner[GSK_CORNER_TOP_RIGHT].width,
self->bounds.origin.y + self->corner[GSK_CORNER_TOP_RIGHT].height,
self->corner[GSK_CORNER_TOP_RIGHT].width,
self->corner[GSK_CORNER_TOP_RIGHT].height,
- G_PI_2, 0);
_cairo_ellipsis (cr,
self->bounds.origin.x + self->bounds.size.width - self->corner[GSK_CORNER_BOTTOM_RIGHT].width,
self->bounds.origin.y + self->bounds.size.height - self->corner[GSK_CORNER_BOTTOM_RIGHT].height,
self->corner[GSK_CORNER_BOTTOM_RIGHT].width,
self->corner[GSK_CORNER_BOTTOM_RIGHT].height,
0, G_PI_2);
_cairo_ellipsis (cr,
self->bounds.origin.x + self->corner[GSK_CORNER_BOTTOM_LEFT].width,
self->bounds.origin.y + self->bounds.size.height - self->corner[GSK_CORNER_BOTTOM_LEFT].height,
self->corner[GSK_CORNER_BOTTOM_LEFT].width,
self->corner[GSK_CORNER_BOTTOM_LEFT].height,
G_PI_2, G_PI);
cairo_close_path (cr);
}
/*< private >
* Converts to the format we use in our shaders:
* vec4 rect;
* vec4 corner_widths;
* vec4 corner_heights;
* rect is (x, y, width, height), the corners are the same
* order as in the rounded rect.
*
* This is so that shaders can use just the first vec4 for
* rectilinear rects, the 2nd vec4 for circular rects and
* only look at the last vec4 if they have to.
*/
void
gsk_rounded_rect_to_float (const GskRoundedRect *self,
float rect[12])
{
guint i;
rect[0] = self->bounds.origin.x;
rect[1] = self->bounds.origin.y;
rect[2] = self->bounds.size.width;
rect[3] = self->bounds.size.height;
for (i = 0; i < 4; i++)
{
rect[4 + i] = self->corner[i].width;
rect[8 + i] = self->corner[i].height;
}
}
gboolean
gsk_rounded_rect_equal (gconstpointer rect1,
gconstpointer rect2)
{
const GskRoundedRect *self1 = rect1;
const GskRoundedRect *self2 = rect2;
return graphene_rect_equal (&self1->bounds, &self2->bounds)
&& graphene_size_equal (&self1->corner[0], &self2->corner[0])
&& graphene_size_equal (&self1->corner[1], &self2->corner[1])
&& graphene_size_equal (&self1->corner[2], &self2->corner[2])
&& graphene_size_equal (&self1->corner[3], &self2->corner[3]);
}