StScrollViewFade: Fix scrollbar size handling

Only skip the areas of the scrollbars when they are invisible
and add take the horizontal scrollbar into account as well
when calculating the faded area.

https://bugzilla.gnome.org/show_bug.cgi?id=651866

diff --git a/src/st/st-scroll-view-fade.c b/src/st/st-scroll-view-fade.c
index 74e430de2e0610a46326289bc4e110620838c86f..e5d5bed2ceb3e657bd00c5ba9761af3bb4128b5f 100644 (file)
--- a/src/st/st-scroll-view-fade.c
+++ b/src/st/st-scroll-view-fade.c
@@ -40,6 +40,7 @@ static const gchar *fade_glsl_shader =
 "uniform float height;\n"
 "uniform float width;\n"
 "uniform float scrollbar_width;\n"
+"uniform float scrollbar_height;\n"
 "uniform float offset_bottom;\n"
 "uniform float offset_top;\n"
 "uniform bool rtl;\n"
@@ -52,10 +53,10 @@ static const gchar *fade_glsl_shader =
 " float ratio = 1.0;\n"
 " float fade_bottom_start = height - offset_bottom;\n"
 " float ratio_top = y / offset_top;\n"
-" float ratio_bottom = (height - y)/(height - fade_bottom_start);\n"
+" float ratio_bottom = (height - scrollbar_height - y)/(height - scrollbar_height - fade_bottom_start);\n"
 " bool in_scroll_area = ((rtl && x > scrollbar_width) || (!rtl && x < (width - scrollbar_width)));\n"
 " bool fade_top = y < offset_top && in_scroll_area;\n"
-" bool fade_bottom = y > fade_bottom_start && in_scroll_area;\n"
+" bool fade_bottom = y > fade_bottom_start && in_scroll_area && (y < (height - scrollbar_height));\n"
 "\n"
 " if (fade_top) {\n"
 "  ratio = ratio_top;\n"
@@ -81,6 +82,7 @@ struct _StScrollViewFade
   gint height_uniform;
   gint width_uniform;
   gint scrollbar_width_uniform;
+  gint scrollbar_height_uniform;
   gint offset_top_uniform;
   gint offset_bottom_uniform;
   gint rtl_uniform;
@@ -145,6 +147,8 @@ st_scroll_view_fade_pre_paint (ClutterEffect *effect)
         cogl_program_get_uniform_location (self->program, "width");
       self->scrollbar_width_uniform =
         cogl_program_get_uniform_location (self->program, "scrollbar_width");
+      self->scrollbar_height_uniform =
+        cogl_program_get_uniform_location (self->program, "scrollbar_height");
       self->rtl_uniform =
         cogl_program_get_uniform_location (self->program, "rtl");
       self->offset_top_uniform =
@@ -177,6 +181,13 @@ st_scroll_view_fade_paint_target (ClutterOffscreenEffect *effect)
 
   gdouble value, lower, upper, page_size;
   ClutterActor *vscroll = st_scroll_view_get_vscroll_bar (ST_SCROLL_VIEW (self->actor));
+  ClutterActor *hscroll = st_scroll_view_get_hscroll_bar (ST_SCROLL_VIEW (self->actor));
+  gboolean h_scroll_visible, v_scroll_visible;
+
+  g_object_get (ST_SCROLL_VIEW (self->actor),
+                "hscrollbar-visible", &h_scroll_visible,
+                "vscrollbar-visible", &v_scroll_visible,
+                NULL);
 
   if (self->program == COGL_INVALID_HANDLE)
     goto out;
@@ -204,7 +215,9 @@ st_scroll_view_fade_paint_target (ClutterOffscreenEffect *effect)
   if (self->width_uniform > -1)
     cogl_program_set_uniform_1f (self->program, self->width_uniform, clutter_actor_get_width (self->actor));
   if (self->scrollbar_width_uniform > -1)
-    cogl_program_set_uniform_1f (self->program, self->scrollbar_width_uniform, clutter_actor_get_width (vscroll));
+    cogl_program_set_uniform_1f (self->program, self->scrollbar_width_uniform, v_scroll_visible ? clutter_actor_get_width (vscroll) : 0);
+  if (self->scrollbar_height_uniform > -1)
+    cogl_program_set_uniform_1f (self->program, self->scrollbar_height_uniform, h_scroll_visible ? clutter_actor_get_height (hscroll) : 0);
   if (self->rtl_uniform > -1)
     cogl_program_set_uniform_1i (self->program, self->rtl_uniform, (st_widget_get_direction (ST_WIDGET (self->actor)) == ST_TEXT_DIRECTION_RTL));
 
@@ -416,6 +429,7 @@ st_scroll_view_fade_init (StScrollViewFade *self)
   self->height_uniform = -1;
   self->width_uniform = -1;
   self->scrollbar_width_uniform = -1;
+  self->scrollbar_height_uniform = -1;
   self->rtl_uniform = -1;
   self->offset_top_uniform = -1;
   self->offset_bottom_uniform = -1;