[gnumeric] About: fix text fading.

[Morten Welinder <mortenw src gnome org>]

commit 30bf943c25bcbe0fd72f0aa045f73b1fb9df7320
Author: Morten Welinder <terra gnome org>
Date:   Thu Dec 25 19:53:55 2014 -0500

    About: fix text fading.

 src/dialogs/ChangeLog      |    5 +++++
 src/dialogs/dialog-about.c |   35 ++++-------------------------------
 2 files changed, 9 insertions(+), 31 deletions(-)
---
diff --git a/src/dialogs/ChangeLog b/src/dialogs/ChangeLog
index 6cc2b4e..7897e45 100644
--- a/src/dialogs/ChangeLog
+++ b/src/dialogs/ChangeLog
@@ -1,3 +1,8 @@
+2014-12-25  Morten Welinder  <terra gnome org>
+
+       * dialog-about.c (text_item_renderer): Fade using alpha.  The old
+       method doesn't work anymore.
+
 2014-12-22  Morten Welinder  <terra gnome org>
 
        * dialog-quit.c (show_quit_dialog): Don't show the dialog.
diff --git a/src/dialogs/dialog-about.c b/src/dialogs/dialog-about.c
index 72a92f7..b69b58f 100644
--- a/src/dialogs/dialog-about.c
+++ b/src/dialogs/dialog-about.c
@@ -194,35 +194,6 @@ struct AboutState_ {
 
 /* ---------------------------------------- */
 
-static GdkRGBA
-blend_colors (const GdkRGBA *start, const GdkRGBA *end, double f)
-{
-       GdkRGBA res;
-       res.red   = start->red   * (1 - f) + end->red   * f;
-       res.green = start->green * (1 - f) + end->green * f;
-       res.blue  = start->blue  * (1 - f) + end->blue  * f;
-       res.alpha = start->alpha * (1 - f) + end->alpha * f;
-       return res;
-}
-
-
-static void
-set_fade (AboutRenderer *r, AboutState *state, double f)
-{
-       GtkStyleContext *ctxt = gtk_widget_get_style_context (state->anim_area);
-       PangoAttrList *attrlist = pango_layout_get_attributes (r->layout);
-       GdkRGBA col, bg, fg;
-       PangoAttribute *attr;
-
-       gtk_style_context_get_color (ctxt, GTK_STATE_FLAG_NORMAL, &fg);
-       gtk_style_context_get_background_color (ctxt, GTK_STATE_FLAG_NORMAL, &bg);
-       col = blend_colors (&bg, &fg, f);
-       attr = pango_attr_foreground_new
-               (col.red * 65535., col.green * 65535., col.blue * 65535.);
-       pango_attr_list_change (attrlist, attr);
-       pango_layout_set_attributes (r->layout, attrlist);
-}
-
 static void
 free_renderer (AboutRenderer *r)
 {
@@ -244,14 +215,15 @@ text_item_renderer (AboutRenderer *r, AboutState *state)
        cairo_t *cr;
        GtkAllocation wa;
        GdkRGBA color;
+       double alpha = 1;
 
        if (age >= r->duration)
                return FALSE;
 
        if (r->fade_in && age < fade)
-               set_fade (r, state, age / (double)fade);
+               alpha = age / (double)fade;
        else if (r->fade_out && r->duration - age < fade)
-               set_fade (r, state, (r->duration - age) / (double)fade);
+               alpha = (r->duration - age) / (double)fade;
 
        ctxt = gtk_widget_get_style_context (widget);
 
@@ -294,6 +266,7 @@ text_item_renderer (AboutRenderer *r, AboutState *state)
 
        cr = r->cr;
        gtk_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);