static gboolean
text_item_renderer (AboutRenderer *r, AboutState *state)
{
PangoLayout *layout = r->layout;
int age = state->now - r->start_time;
double rage = CLAMP (age / (double)r->duration, 0.0, 1.0);
GtkWidget *widget = state->anim_area;
GtkStyleContext *ctxt;
const int fade = 500;
int x, y, width, height;
cairo_t *cr;
GtkAllocation wa;
GdkRGBA color;
double alpha = 1;
if (age >= r->duration)
return FALSE;
if (r->fade_in && age < fade)
alpha = age / (double)fade;
else if (r->fade_out && r->duration - age < fade)
alpha = (r->duration - age) / (double)fade;
ctxt = gtk_widget_get_style_context (widget);
gtk_widget_get_allocation (widget, &wa);
x = (int)(PANGO_SCALE * wa.width *
(r->start.x + rage * (r->end.x - r->start.x)));
y = (int)(PANGO_SCALE * wa.height *
(r->start.y + rage * (r->end.y - r->start.y)));
if (r->expansion.count) {
PangoAttrList *attrlist = pango_layout_get_attributes (layout);
const char *p, *text = pango_layout_get_text (layout);
PangoRectangle ink, logical;
memset (&ink, 0, sizeof (ink));
logical = ink;
logical.width = (int)(rage * r->expansion.rate * r->natural_width / r->expansion.count);
p = text;
while (*p) {
const char *next = g_utf8_next_char (p);
gunichar uc = g_utf8_get_char (p);
PangoAttribute *attr;
if (uc == UNICODE_ZERO_WIDTH_SPACE_C) {
attr = pango_attr_shape_new (&ink, &logical);
attr->start_index = p - text;
attr->end_index = next - text;
pango_attr_list_change (attrlist, attr);
}
p = next;
}
pango_layout_set_attributes (layout, attrlist);
}
pango_layout_get_size (layout, &width, &height);
x -= width / 2;
y -= height / 2;
cr = r->cr;
gnm_style_context_get_color (ctxt, GTK_STATE_FLAG_NORMAL, &color);
color.alpha = alpha;
gdk_cairo_set_source_rgba (cr, &color);
cairo_move_to (cr, x / (double)PANGO_SCALE, y / (double)PANGO_SCALE);
pango_cairo_show_layout (cr, layout);
return TRUE;
}
static void
decorate_text (GimpAboutDialog *dialog,
gint anim_type,
gdouble time)
{
GtkStyle *style = gtk_widget_get_style (dialog->anim_area);
const gchar *text;
const gchar *ptr;
gint letter_count = 0;
gint text_length = 0;
gint text_bytelen = 0;
gint cluster_start, cluster_end;
gunichar unichr;
PangoAttrList *attrlist = NULL;
PangoAttribute *attr;
PangoRectangle irect = {0, 0, 0, 0};
PangoRectangle lrect = {0, 0, 0, 0};
GdkColor mix;
mix_colors (style->bg + GTK_STATE_NORMAL,
style->fg + GTK_STATE_NORMAL, &mix, time);
text = pango_layout_get_text (dialog->layout);
g_return_if_fail (text != NULL);
text_length = g_utf8_strlen (text, -1);
text_bytelen = strlen (text);
attrlist = pango_attr_list_new ();
dialog->textrange[0] = 0;
dialog->textrange[1] = text_bytelen;
switch (anim_type)
{
case 0: /* Fade in */
attr = pango_attr_foreground_new (mix.red, mix.green, mix.blue);
attr->start_index = 0;
attr->end_index = text_bytelen;
pango_attr_list_insert (attrlist, attr);
break;
case 1: /* Fade in, spread */
attr = pango_attr_foreground_new (mix.red, mix.green, mix.blue);
attr->start_index = 0;
attr->end_index = text_bytelen;
pango_attr_list_change (attrlist, attr);
ptr = text;
cluster_start = 0;
while ((unichr = g_utf8_get_char (ptr)))
{
ptr = g_utf8_next_char (ptr);
cluster_end = (ptr - text);
if (unichr == 0x200b)
{
lrect.width = (1.0 - time) * 15.0 * PANGO_SCALE + 0.5;
attr = pango_attr_shape_new (&irect, &lrect);
attr->start_index = cluster_start;
attr->end_index = cluster_end;
pango_attr_list_change (attrlist, attr);
}
cluster_start = cluster_end;
}
break;
case 2: /* Fade in, sinewave */
attr = pango_attr_foreground_new (mix.red, mix.green, mix.blue);
attr->start_index = 0;
attr->end_index = text_bytelen;
pango_attr_list_change (attrlist, attr);
ptr = text;
cluster_start = 0;
while ((unichr = g_utf8_get_char (ptr)))
{
if (unichr == 0x200b)
{
cluster_end = ptr - text;
attr = pango_attr_rise_new ((1.0 -time) * 18000 *
sin (4.0 * time +
(float) letter_count * 0.7));
attr->start_index = cluster_start;
attr->end_index = cluster_end;
pango_attr_list_change (attrlist, attr);
letter_count++;
cluster_start = cluster_end;
}
ptr = g_utf8_next_char (ptr);
}
break;
case 3: /* letterwise Fade in */
ptr = text;
letter_count = 0;
cluster_start = 0;
while ((unichr = g_utf8_get_char (ptr)))
{
gint border = (text_length + 15) * time - 15;
gdouble pos;
if (letter_count < border)
pos = 0;
else if (letter_count > border + 15)
pos = 1;
else
pos = ((gdouble) (letter_count - border)) / 15;
mix_colors (style->fg + GTK_STATE_NORMAL,
style->bg + GTK_STATE_NORMAL,
&mix, pos);
ptr = g_utf8_next_char (ptr);
cluster_end = ptr - text;
attr = pango_attr_foreground_new (mix.red, mix.green, mix.blue);
attr->start_index = cluster_start;
attr->end_index = cluster_end;
pango_attr_list_change (attrlist, attr);
if (pos < 1.0)
dialog->textrange[1] = cluster_end;
letter_count++;
cluster_start = cluster_end;
}
break;
default:
g_printerr ("Unknown animation type %d\n", anim_type);
}
pango_layout_set_attributes (dialog->layout, attrlist);
pango_attr_list_unref (attrlist);
}
