gtk2/gtk/gtkcsseasevalue.c
Benjamin Otte d9ef734458 cssparser: Simplify
Remove the uint parser (and use the int parser in the one user of it).

And avoid unnecessarily going through a macro.
2019-03-22 19:55:34 +01:00

390 lines
11 KiB
C

/* GTK - The GIMP Toolkit
* Copyright (C) 2011 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 "gtkcsseasevalueprivate.h"
#include <math.h>
typedef enum {
GTK_CSS_EASE_CUBIC_BEZIER,
GTK_CSS_EASE_STEPS
} GtkCssEaseType;
struct _GtkCssValue {
GTK_CSS_VALUE_BASE
GtkCssEaseType type;
union {
struct {
double x1;
double y1;
double x2;
double y2;
} cubic;
struct {
guint steps;
gboolean start;
} steps;
} u;
};
static void
gtk_css_value_ease_free (GtkCssValue *value)
{
g_slice_free (GtkCssValue, value);
}
static GtkCssValue *
gtk_css_value_ease_compute (GtkCssValue *value,
guint property_id,
GtkStyleProvider *provider,
GtkCssStyle *style,
GtkCssStyle *parent_style)
{
return _gtk_css_value_ref (value);
}
static gboolean
gtk_css_value_ease_equal (const GtkCssValue *ease1,
const GtkCssValue *ease2)
{
if (ease1->type != ease2->type)
return FALSE;
switch (ease1->type)
{
case GTK_CSS_EASE_CUBIC_BEZIER:
return ease1->u.cubic.x1 == ease2->u.cubic.x1 &&
ease1->u.cubic.y1 == ease2->u.cubic.y1 &&
ease1->u.cubic.x2 == ease2->u.cubic.x2 &&
ease1->u.cubic.y2 == ease2->u.cubic.y2;
case GTK_CSS_EASE_STEPS:
return ease1->u.steps.steps == ease2->u.steps.steps &&
ease1->u.steps.start == ease2->u.steps.start;
default:
g_assert_not_reached ();
return FALSE;
}
}
static GtkCssValue *
gtk_css_value_ease_transition (GtkCssValue *start,
GtkCssValue *end,
guint property_id,
double progress)
{
return NULL;
}
static void
gtk_css_value_ease_print (const GtkCssValue *ease,
GString *string)
{
switch (ease->type)
{
case GTK_CSS_EASE_CUBIC_BEZIER:
if (ease->u.cubic.x1 == 0.25 && ease->u.cubic.y1 == 0.1 &&
ease->u.cubic.x2 == 0.25 && ease->u.cubic.y2 == 1.0)
g_string_append (string, "ease");
else if (ease->u.cubic.x1 == 0.0 && ease->u.cubic.y1 == 0.0 &&
ease->u.cubic.x2 == 1.0 && ease->u.cubic.y2 == 1.0)
g_string_append (string, "linear");
else if (ease->u.cubic.x1 == 0.42 && ease->u.cubic.y1 == 0.0 &&
ease->u.cubic.x2 == 1.0 && ease->u.cubic.y2 == 1.0)
g_string_append (string, "ease-in");
else if (ease->u.cubic.x1 == 0.0 && ease->u.cubic.y1 == 0.0 &&
ease->u.cubic.x2 == 0.58 && ease->u.cubic.y2 == 1.0)
g_string_append (string, "ease-out");
else if (ease->u.cubic.x1 == 0.42 && ease->u.cubic.y1 == 0.0 &&
ease->u.cubic.x2 == 0.58 && ease->u.cubic.y2 == 1.0)
g_string_append (string, "ease-in-out");
else
g_string_append_printf (string, "cubic-bezier(%g,%g,%g,%g)",
ease->u.cubic.x1, ease->u.cubic.y1,
ease->u.cubic.x2, ease->u.cubic.y2);
break;
case GTK_CSS_EASE_STEPS:
if (ease->u.steps.steps == 1)
{
g_string_append (string, ease->u.steps.start ? "step-start" : "step-end");
}
else
{
g_string_append_printf (string, "steps(%u%s)", ease->u.steps.steps, ease->u.steps.start ? ",start" : "");
}
break;
default:
g_assert_not_reached ();
break;
}
}
static const GtkCssValueClass GTK_CSS_VALUE_EASE = {
gtk_css_value_ease_free,
gtk_css_value_ease_compute,
gtk_css_value_ease_equal,
gtk_css_value_ease_transition,
NULL,
NULL,
gtk_css_value_ease_print
};
GtkCssValue *
_gtk_css_ease_value_new_cubic_bezier (double x1,
double y1,
double x2,
double y2)
{
GtkCssValue *value;
g_return_val_if_fail (x1 >= 0.0, NULL);
g_return_val_if_fail (x1 <= 1.0, NULL);
g_return_val_if_fail (x2 >= 0.0, NULL);
g_return_val_if_fail (x2 <= 1.0, NULL);
value = _gtk_css_value_new (GtkCssValue, &GTK_CSS_VALUE_EASE);
value->type = GTK_CSS_EASE_CUBIC_BEZIER;
value->u.cubic.x1 = x1;
value->u.cubic.y1 = y1;
value->u.cubic.x2 = x2;
value->u.cubic.y2 = y2;
return value;
}
static GtkCssValue *
_gtk_css_ease_value_new_steps (guint n_steps,
gboolean start)
{
GtkCssValue *value;
g_return_val_if_fail (n_steps > 0, NULL);
value = _gtk_css_value_new (GtkCssValue, &GTK_CSS_VALUE_EASE);
value->type = GTK_CSS_EASE_STEPS;
value->u.steps.steps = n_steps;
value->u.steps.start = start;
return value;
}
static const struct {
const char *name;
guint is_bezier :1;
guint needs_custom :1;
double values[4];
} parser_values[] = {
{ "linear", TRUE, FALSE, { 0.0, 0.0, 1.0, 1.0 } },
{ "ease-in-out", TRUE, FALSE, { 0.42, 0.0, 0.58, 1.0 } },
{ "ease-in", TRUE, FALSE, { 0.42, 0.0, 1.0, 1.0 } },
{ "ease-out", TRUE, FALSE, { 0.0, 0.0, 0.58, 1.0 } },
{ "ease", TRUE, FALSE, { 0.25, 0.1, 0.25, 1.0 } },
{ "step-start", FALSE, FALSE, { 1.0, 1.0, 0.0, 0.0 } },
{ "step-end", FALSE, FALSE, { 1.0, 0.0, 0.0, 0.0 } },
{ "steps", FALSE, TRUE, { 0.0, 0.0, 0.0, 0.0 } },
{ "cubic-bezier", TRUE, TRUE, { 0.0, 0.0, 0.0, 0.0 } }
};
gboolean
_gtk_css_ease_value_can_parse (GtkCssParser *parser)
{
guint i;
for (i = 0; i < G_N_ELEMENTS (parser_values); i++)
{
if (_gtk_css_parser_has_prefix (parser, parser_values[i].name))
return TRUE;
}
return FALSE;
}
static GtkCssValue *
gtk_css_ease_value_parse_cubic_bezier (GtkCssParser *parser)
{
double values[4];
guint i;
for (i = 0; i < 4; i++)
{
if (!_gtk_css_parser_try (parser, i ? "," : "(", TRUE))
{
_gtk_css_parser_error (parser, "Expected '%s'", i ? "," : "(");
return NULL;
}
if (!_gtk_css_parser_try_double (parser, &values[i]))
{
_gtk_css_parser_error (parser, "Expected a number");
return NULL;
}
if ((i == 0 || i == 2) &&
(values[i] < 0 || values[i] > 1.0))
{
_gtk_css_parser_error (parser, "value %g out of range. Must be from 0.0 to 1.0", values[i]);
return NULL;
}
}
if (!_gtk_css_parser_try (parser, ")", TRUE))
{
_gtk_css_parser_error (parser, "Missing closing ')' for cubic-bezier");
return NULL;
}
return _gtk_css_ease_value_new_cubic_bezier (values[0], values[1], values[2], values[3]);
}
static GtkCssValue *
gtk_css_ease_value_parse_steps (GtkCssParser *parser)
{
int n_steps;
gboolean start;
if (!_gtk_css_parser_try (parser, "(", TRUE))
{
_gtk_css_parser_error (parser, "Expected '('");
return NULL;
}
if (!_gtk_css_parser_try_int (parser, &n_steps))
{
_gtk_css_parser_error (parser, "Expected number of steps");
return NULL;
}
else if (n_steps < 1)
{
_gtk_css_parser_error (parser, "Number of steps must be > 0");
return NULL;
}
if (_gtk_css_parser_try (parser, ",", TRUE))
{
if (_gtk_css_parser_try (parser, "start", TRUE))
start = TRUE;
else if (_gtk_css_parser_try (parser, "end", TRUE))
start = FALSE;
else
{
_gtk_css_parser_error (parser, "Only allowed values are 'start' and 'end'");
return NULL;
}
}
else
start = FALSE;
if (!_gtk_css_parser_try (parser, ")", TRUE))
{
_gtk_css_parser_error (parser, "Missing closing ')' for steps");
return NULL;
}
return _gtk_css_ease_value_new_steps (n_steps, start);
}
GtkCssValue *
_gtk_css_ease_value_parse (GtkCssParser *parser)
{
guint i;
g_return_val_if_fail (parser != NULL, NULL);
for (i = 0; i < G_N_ELEMENTS (parser_values); i++)
{
if (_gtk_css_parser_try (parser, parser_values[i].name, FALSE))
{
if (parser_values[i].needs_custom)
{
if (parser_values[i].is_bezier)
return gtk_css_ease_value_parse_cubic_bezier (parser);
else
return gtk_css_ease_value_parse_steps (parser);
}
_gtk_css_parser_skip_whitespace (parser);
if (parser_values[i].is_bezier)
return _gtk_css_ease_value_new_cubic_bezier (parser_values[i].values[0],
parser_values[i].values[1],
parser_values[i].values[2],
parser_values[i].values[3]);
else
return _gtk_css_ease_value_new_steps (parser_values[i].values[0],
parser_values[i].values[1] != 0.0);
}
}
_gtk_css_parser_error (parser, "Unknown value");
return NULL;
}
double
_gtk_css_ease_value_transform (const GtkCssValue *ease,
double progress)
{
g_return_val_if_fail (ease->class == &GTK_CSS_VALUE_EASE, 1.0);
if (progress <= 0)
return 0;
if (progress >= 1)
return 1;
switch (ease->type)
{
case GTK_CSS_EASE_CUBIC_BEZIER:
{
static const double epsilon = 0.00001;
double tmin, t, tmax;
tmin = 0.0;
tmax = 1.0;
t = progress;
while (tmin < tmax)
{
double sample;
sample = (((1.0 + 3 * ease->u.cubic.x1 - 3 * ease->u.cubic.x2) * t
+ -6 * ease->u.cubic.x1 + 3 * ease->u.cubic.x2) * t
+ 3 * ease->u.cubic.x1 ) * t;
if (fabs(sample - progress) < epsilon)
break;
if (progress > sample)
tmin = t;
else
tmax = t;
t = (tmax + tmin) * .5;
}
return (((1.0 + 3 * ease->u.cubic.y1 - 3 * ease->u.cubic.y2) * t
+ -6 * ease->u.cubic.y1 + 3 * ease->u.cubic.y2) * t
+ 3 * ease->u.cubic.y1 ) * t;
}
case GTK_CSS_EASE_STEPS:
progress *= ease->u.steps.steps;
progress = floor (progress) + (ease->u.steps.start ? 0 : 1);
return progress / ease->u.steps.steps;
default:
g_assert_not_reached ();
return 1.0;
}
}