gnome-shell/src/st/st-private.c

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/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
#include <math.h>
#include <string.h>
#include "st-private.h"
/**
* _st_actor_get_preferred_width:
* @actor: a #ClutterActor
* @for_height: as with clutter_actor_get_preferred_width()
* @y_fill: %TRUE if @actor will fill its allocation vertically
* @min_width_p: as with clutter_actor_get_preferred_width()
* @natural_width_p: as with clutter_actor_get_preferred_width()
*
* Like clutter_actor_get_preferred_width(), but if @y_fill is %FALSE,
* then it will compute a width request based on the assumption that
* @actor will be given an allocation no taller than its natural
* height.
*/
void
_st_actor_get_preferred_width (ClutterActor *actor,
gfloat for_height,
gboolean y_fill,
gfloat *min_width_p,
gfloat *natural_width_p)
{
if (!y_fill && for_height != -1)
{
ClutterRequestMode mode;
gfloat natural_height;
g_object_get (G_OBJECT (actor), "request-mode", &mode, NULL);
if (mode == CLUTTER_REQUEST_WIDTH_FOR_HEIGHT)
{
clutter_actor_get_preferred_height (actor, -1, NULL, &natural_height);
if (for_height > natural_height)
for_height = natural_height;
}
}
clutter_actor_get_preferred_width (actor, for_height, min_width_p, natural_width_p);
}
/**
* _st_actor_get_preferred_height:
* @actor: a #ClutterActor
* @for_width: as with clutter_actor_get_preferred_height()
* @x_fill: %TRUE if @actor will fill its allocation horizontally
* @min_height_p: as with clutter_actor_get_preferred_height()
* @natural_height_p: as with clutter_actor_get_preferred_height()
*
* Like clutter_actor_get_preferred_height(), but if @x_fill is
* %FALSE, then it will compute a height request based on the
* assumption that @actor will be given an allocation no wider than
* its natural width.
*/
void
_st_actor_get_preferred_height (ClutterActor *actor,
gfloat for_width,
gboolean x_fill,
gfloat *min_height_p,
gfloat *natural_height_p)
{
if (!x_fill && for_width != -1)
{
ClutterRequestMode mode;
gfloat natural_width;
g_object_get (G_OBJECT (actor), "request-mode", &mode, NULL);
if (mode == CLUTTER_REQUEST_HEIGHT_FOR_WIDTH)
{
clutter_actor_get_preferred_width (actor, -1, NULL, &natural_width);
if (for_width > natural_width)
for_width = natural_width;
}
}
clutter_actor_get_preferred_height (actor, for_width, min_height_p, natural_height_p);
}
/**
* _st_allocate_fill:
* @parent: the parent #StWidget
* @child: the child (not necessarily an #StWidget)
* @childbox: total space that could be allocated to @child
* @x_alignment: horizontal alignment within @childbox
* @y_alignment: vertical alignment within @childbox
* @x_fill: whether or not to fill @childbox horizontally
* @y_fill: whether or not to fill @childbox vertically
*
* Given @childbox, containing the initial allocation of @child, this
* adjusts the horizontal allocation if @x_fill is %FALSE, and the
* vertical allocation if @y_fill is %FALSE, by:
*
* - reducing the allocation if it is larger than @child's natural
* size.
*
* - adjusting the position of the child within the allocation
* according to @x_alignment/@y_alignment (and flipping
* @x_alignment if @parent has %ST_TEXT_DIRECTION_RTL)
*
* If @x_fill and @y_fill are both %TRUE, or if @child's natural size
* is larger than the initial allocation in @childbox, then @childbox
* will be unchanged.
*
* If you are allocating children with _st_allocate_fill(), you should
* determine their preferred sizes using
* _st_actor_get_preferred_width() and
* _st_actor_get_preferred_height(), not with the corresponding
* Clutter methods.
*/
void
_st_allocate_fill (StWidget *parent,
ClutterActor *child,
ClutterActorBox *childbox,
StAlign x_alignment,
StAlign y_alignment,
gboolean x_fill,
gboolean y_fill)
{
gfloat natural_width, natural_height;
gfloat min_width, min_height;
gfloat child_width, child_height;
gfloat available_width, available_height;
ClutterRequestMode request;
gdouble x_align, y_align;
available_width = childbox->x2 - childbox->x1;
available_height = childbox->y2 - childbox->y1;
if (available_width < 0)
{
available_width = 0;
childbox->x2 = childbox->x1;
}
if (available_height < 0)
{
available_height = 0;
childbox->y2 = childbox->y1;
}
/* If we are filling both horizontally and vertically then we don't
* need to do anything else.
*/
if (x_fill && y_fill)
return;
_st_get_align_factors (parent, x_alignment, y_alignment,
&x_align, &y_align);
/* The following is based on clutter_actor_get_preferred_size(), but
* modified to cope with the fact that the available size may be
* less than the preferred size.
*/
request = CLUTTER_REQUEST_HEIGHT_FOR_WIDTH;
g_object_get (G_OBJECT (child), "request-mode", &request, NULL);
if (request == CLUTTER_REQUEST_HEIGHT_FOR_WIDTH)
{
clutter_actor_get_preferred_width (child, -1,
&min_width,
&natural_width);
child_width = CLAMP (natural_width, min_width, available_width);
clutter_actor_get_preferred_height (child, child_width,
&min_height,
&natural_height);
child_height = CLAMP (natural_height, min_height, available_height);
}
else
{
clutter_actor_get_preferred_height (child, -1,
&min_height,
&natural_height);
child_height = CLAMP (natural_height, min_height, available_height);
clutter_actor_get_preferred_width (child, child_height,
&min_width,
&natural_width);
child_width = CLAMP (natural_width, min_width, available_width);
}
if (!x_fill)
{
childbox->x1 += (int)((available_width - child_width) * x_align);
childbox->x2 = childbox->x1 + (int) child_width;
}
if (!y_fill)
{
childbox->y1 += (int)((available_height - child_height) * y_align);
childbox->y2 = childbox->y1 + (int) child_height;
}
}
/**
* _st_get_align_factors:
* @widget: an #StWidget
* @x_align: an #StAlign
* @y_align: an #StAlign
* @x_align_out: (out) (allow-none): @x_align as a #gdouble
* @y_align_out: (out) (allow-none): @y_align as a #gdouble
*
* Converts @x_align and @y_align to #gdouble values. If @widget has
* %ST_TEXT_DIRECTION_RTL, the @x_align_out value will be flipped
* relative to @x_align.
*/
void
_st_get_align_factors (StWidget *widget,
StAlign x_align,
StAlign y_align,
gdouble *x_align_out,
gdouble *y_align_out)
{
if (x_align_out)
{
switch (x_align)
{
case ST_ALIGN_START:
*x_align_out = 0.0;
break;
case ST_ALIGN_MIDDLE:
*x_align_out = 0.5;
break;
case ST_ALIGN_END:
*x_align_out = 1.0;
break;
default:
g_warn_if_reached ();
break;
}
if (st_widget_get_direction (widget) == ST_TEXT_DIRECTION_RTL)
*x_align_out = 1.0 - *x_align_out;
}
if (y_align_out)
{
switch (y_align)
{
case ST_ALIGN_START:
*y_align_out = 0.0;
break;
case ST_ALIGN_MIDDLE:
*y_align_out = 0.5;
break;
case ST_ALIGN_END:
*y_align_out = 1.0;
break;
default:
g_warn_if_reached ();
break;
}
}
}
/**
* _st_set_text_from_style:
* @text: Target #ClutterText
* @theme_node: Source #StThemeNode
*
* Set various GObject properties of the @text object using
* CSS information from @theme_node.
*/
void
_st_set_text_from_style (ClutterText *text,
StThemeNode *theme_node)
{
ClutterColor color;
StTextDecoration decoration;
PangoAttrList *attribs;
const PangoFontDescription *font;
gchar *font_string;
StTextAlign align;
st_theme_node_get_foreground_color (theme_node, &color);
clutter_text_set_color (text, &color);
font = st_theme_node_get_font (theme_node);
font_string = pango_font_description_to_string (font);
clutter_text_set_font_name (text, font_string);
g_free (font_string);
attribs = pango_attr_list_new ();
decoration = st_theme_node_get_text_decoration (theme_node);
if (decoration & ST_TEXT_DECORATION_UNDERLINE)
{
PangoAttribute *underline = pango_attr_underline_new (PANGO_UNDERLINE_SINGLE);
pango_attr_list_insert (attribs, underline);
}
if (decoration & ST_TEXT_DECORATION_LINE_THROUGH)
{
PangoAttribute *strikethrough = pango_attr_strikethrough_new (TRUE);
pango_attr_list_insert (attribs, strikethrough);
}
/* Pango doesn't have an equivalent attribute for _OVERLINE, and we deliberately
* skip BLINK (for now...)
*/
clutter_text_set_attributes (text, attribs);
pango_attr_list_unref (attribs);
align = st_theme_node_get_text_align (theme_node);
if(align == ST_TEXT_ALIGN_JUSTIFY) {
clutter_text_set_justify (text, TRUE);
clutter_text_set_line_alignment (text, PANGO_ALIGN_LEFT);
} else {
clutter_text_set_justify (text, FALSE);
clutter_text_set_line_alignment (text, (PangoAlignment) align);
}
}
/**
* _st_create_texture_material:
* @src_texture: The CoglTexture for the material
*
* Creates a simple material which contains the given texture as a
* single layer.
*/
CoglHandle
_st_create_texture_material (CoglHandle src_texture)
{
static CoglHandle texture_material_template = COGL_INVALID_HANDLE;
CoglHandle material;
g_return_val_if_fail (src_texture != COGL_INVALID_HANDLE,
COGL_INVALID_HANDLE);
/* We use a material that has a dummy texture as a base for all
texture materials. The idea is that only the Cogl texture object
would be different in the children so it is likely that Cogl will
be able to share GL programs between all the textures. */
if (G_UNLIKELY (texture_material_template == COGL_INVALID_HANDLE))
{
static const guint8 white_pixel[] = { 0xff, 0xff, 0xff, 0xff };
CoglHandle dummy_texture;
dummy_texture =
cogl_texture_new_from_data (1, 1,
COGL_TEXTURE_NONE,
COGL_PIXEL_FORMAT_RGBA_8888_PRE,
COGL_PIXEL_FORMAT_ANY,
4, white_pixel);
texture_material_template = cogl_material_new ();
cogl_material_set_layer (texture_material_template, 0, dummy_texture);
cogl_handle_unref (dummy_texture);
}
material = cogl_material_copy (texture_material_template);
cogl_material_set_layer (material, 0, src_texture);
return material;
}
/*****
* Shadows
*****/
static gdouble *
calculate_gaussian_kernel (gdouble sigma,
guint n_values)
{
gdouble *ret, sum;
gdouble exp_divisor;
gint half, i;
g_return_val_if_fail (sigma > 0, NULL);
half = n_values / 2;
ret = g_malloc (n_values * sizeof (gdouble));
sum = 0.0;
exp_divisor = 2 * sigma * sigma;
/* n_values of 1D Gauss function */
for (i = 0; i < n_values; i++)
{
ret[i] = exp (-(i - half) * (i - half) / exp_divisor);
sum += ret[i];
}
/* normalize */
for (i = 0; i < n_values; i++)
ret[i] /= sum;
return ret;
}
CoglHandle
_st_create_shadow_material (StShadow *shadow_spec,
CoglHandle src_texture)
{
static CoglHandle shadow_material_template = COGL_INVALID_HANDLE;
CoglHandle material;
CoglHandle texture;
guchar *pixels_in, *pixels_out;
gint width_in, height_in, rowstride_in;
gint width_out, height_out, rowstride_out;
float sigma;
g_return_val_if_fail (shadow_spec != NULL, COGL_INVALID_HANDLE);
g_return_val_if_fail (src_texture != COGL_INVALID_HANDLE,
COGL_INVALID_HANDLE);
/* we use an approximation of the sigma - blur radius relationship used
in Firefox for doing SVG blurs; see
http://mxr.mozilla.org/mozilla-central/source/gfx/thebes/src/gfxBlur.cpp#280
*/
sigma = shadow_spec->blur / 1.9;
width_in = cogl_texture_get_width (src_texture);
height_in = cogl_texture_get_height (src_texture);
rowstride_in = (width_in + 3) & ~3;
pixels_in = g_malloc0 (rowstride_in * height_in);
cogl_texture_get_data (src_texture, COGL_PIXEL_FORMAT_A_8,
rowstride_in, pixels_in);
if ((guint) shadow_spec->blur == 0)
{
width_out = width_in;
height_out = height_in;
rowstride_out = rowstride_in;
pixels_out = g_memdup (pixels_in, rowstride_out * height_out);
}
else
{
gdouble *kernel;
guchar *line;
gint n_values, half;
gint x_in, y_in, x_out, y_out, i;
n_values = (gint) 5 * sigma;
half = n_values / 2;
width_out = width_in + 2 * half;
height_out = height_in + 2 * half;
rowstride_out = (width_out + 3) & ~3;
pixels_out = g_malloc0 (rowstride_out * height_out);
line = g_malloc0 (rowstride_out);
kernel = calculate_gaussian_kernel (sigma, n_values);
/* vertical blur */
for (x_in = 0; x_in < width_in; x_in++)
for (y_out = 0; y_out < height_out; y_out++)
{
guchar *pixel_in, *pixel_out;
gint i0, i1;
y_in = y_out - half;
/* We read from the source at 'y = y_in + i - half'; clamp the
* full i range [0, n_values) so that y is in [0, height_in).
*/
i0 = MAX (half - y_in, 0);
i1 = MIN (height_in + half - y_in, n_values);
pixel_in = pixels_in + (y_in + i0 - half) * rowstride_in + x_in;
pixel_out = pixels_out + y_out * rowstride_out + (x_in + half);
for (i = i0; i < i1; i++)
{
*pixel_out += *pixel_in * kernel[i];
pixel_in += rowstride_in;
}
}
/* horizontal blur */
for (y_out = 0; y_out < height_out; y_out++)
{
memcpy (line, pixels_out + y_out * rowstride_out, rowstride_out);
for (x_out = 0; x_out < width_out; x_out++)
{
gint i0, i1;
guchar *pixel_out, *pixel_in;
/* We read from the source at 'x = x_out + i - half'; clamp the
* full i range [0, n_values) so that x is in [0, width_out).
*/
i0 = MAX (half - x_out, 0);
i1 = MIN (width_out + half - x_out, n_values);
pixel_in = line + x_out + i0 - half;
pixel_out = pixels_out + rowstride_out * y_out + x_out;
*pixel_out = 0;
for (i = i0; i < i1; i++)
{
*pixel_out += *pixel_in * kernel[i];
pixel_in++;
}
}
}
g_free (kernel);
g_free (line);
}
texture = cogl_texture_new_from_data (width_out,
height_out,
COGL_TEXTURE_NONE,
COGL_PIXEL_FORMAT_A_8,
COGL_PIXEL_FORMAT_A_8,
rowstride_out,
pixels_out);
g_free (pixels_in);
g_free (pixels_out);
if (G_UNLIKELY (shadow_material_template == COGL_INVALID_HANDLE))
{
shadow_material_template = cogl_material_new ();
/* We set up the material to blend the shadow texture with the combine
* constant, but defer setting the latter until painting, so that we can
* take the actor's overall opacity into account. */
cogl_material_set_layer_combine (shadow_material_template, 0,
"RGBA = MODULATE (CONSTANT, TEXTURE[A])",
NULL);
}
material = cogl_material_copy (shadow_material_template);
cogl_material_set_layer (material, 0, texture);
cogl_handle_unref (texture);
return material;
}
CoglHandle
_st_create_shadow_material_from_actor (StShadow *shadow_spec,
ClutterActor *actor)
{
CoglHandle shadow_material = COGL_INVALID_HANDLE;
if (CLUTTER_IS_TEXTURE (actor))
{
CoglHandle texture;
texture = clutter_texture_get_cogl_texture (CLUTTER_TEXTURE (actor));
shadow_material = _st_create_shadow_material (shadow_spec, texture);
}
else
{
CoglHandle buffer, offscreen;
ClutterActorBox box;
float width, height;
clutter_actor_get_allocation_box (actor, &box);
clutter_actor_box_get_size (&box, &width, &height);
buffer = cogl_texture_new_with_size (width,
height,
COGL_TEXTURE_NO_SLICING,
COGL_PIXEL_FORMAT_ANY);
offscreen = cogl_offscreen_new_to_texture (buffer);
if (offscreen != COGL_INVALID_HANDLE)
{
CoglColor clear_color;
cogl_color_set_from_4ub (&clear_color, 0, 0, 0, 0);
cogl_push_framebuffer (offscreen);
cogl_clear (&clear_color, COGL_BUFFER_BIT_COLOR);
cogl_ortho (0, width, height, 0, 0, 1.0);
clutter_actor_paint (actor);
cogl_pop_framebuffer ();
cogl_handle_unref (offscreen);
shadow_material = _st_create_shadow_material (shadow_spec, buffer);
}
cogl_handle_unref (buffer);
}
return shadow_material;
}
void
_st_paint_shadow_with_opacity (StShadow *shadow_spec,
CoglHandle shadow_material,
ClutterActorBox *box,
guint8 paint_opacity)
{
ClutterActorBox shadow_box;
CoglColor color;
g_return_if_fail (shadow_spec != NULL);
g_return_if_fail (shadow_material != COGL_INVALID_HANDLE);
st_shadow_get_box (shadow_spec, box, &shadow_box);
cogl_color_set_from_4ub (&color,
shadow_spec->color.red * paint_opacity / 255,
shadow_spec->color.green * paint_opacity / 255,
shadow_spec->color.blue * paint_opacity / 255,
shadow_spec->color.alpha * paint_opacity / 255);
cogl_color_premultiply (&color);
cogl_material_set_layer_combine_constant (shadow_material, 0, &color);
cogl_set_source (shadow_material);
cogl_rectangle_with_texture_coords (shadow_box.x1, shadow_box.y1,
shadow_box.x2, shadow_box.y2,
0, 0, 1, 1);
}