[gnome-shell/wip/carlosg/appgrid-navigation: 24/24] st/scrollview: Apply correct fade_edges_left/right effect uniforms in RTL

[Marge Bot <marge-bot src gnome org>]

commit 40b67a140a49843ddd794b09ad6a2104b61643bd
Author: Carlos Garnacho <carlosg gnome org>
Date:   Sat Feb 27 20:23:19 2021 +0100

    st/scrollview: Apply correct fade_edges_left/right effect uniforms in RTL
    
    When the setting is false, we apply anyway depending on the adjustment
    value. Look for the right value corresponding to that side as per the
    locale.
    
    Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1630>

 src/st/st-scroll-view-fade.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)
---
diff --git a/src/st/st-scroll-view-fade.c b/src/st/st-scroll-view-fade.c
index 3ca7313372..b387e384a5 100644
--- a/src/st/st-scroll-view-fade.c
+++ b/src/st/st-scroll-view-fade.c
@@ -94,7 +94,7 @@ 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;
+  gboolean h_scroll_visible, v_scroll_visible, rtl;
 
   ClutterActorBox allocation, content_box, paint_box;
   ClutterMargin *content_padding;
@@ -158,8 +158,15 @@ st_scroll_view_fade_paint_target (ClutterOffscreenEffect *effect,
 
   st_adjustment_get_values (self->hadjustment, &value, &lower, &upper, NULL, NULL, &page_size);
   value = (value - lower) / (upper - page_size - lower);
-  clutter_shader_effect_set_uniform (shader, "fade_edges_left", G_TYPE_INT, 1, self->fade_edges ? value >= 
0.0 : value > 0.0);
-  clutter_shader_effect_set_uniform (shader, "fade_edges_right", G_TYPE_INT, 1, self->fade_edges ? value <= 
1.0 : value < 1.0);
+  rtl = clutter_actor_get_text_direction (self->actor) == CLUTTER_TEXT_DIRECTION_RTL;
+  clutter_shader_effect_set_uniform (shader, "fade_edges_left", G_TYPE_INT, 1,
+                                     self->fade_edges ?
+                                     value >= 0.0 :
+                                     (rtl ? value < 1.0 : value > 0.0));
+  clutter_shader_effect_set_uniform (shader, "fade_edges_right", G_TYPE_INT, 1,
+                                     self->fade_edges ?
+                                     value <= 1.0 :
+                                     (rtl ? value > 0.0 : value < 1.0));
 
   clutter_shader_effect_set_uniform (shader, "fade_offset_top", G_TYPE_FLOAT, 1, ABS 
(self->fade_margins.top));
   clutter_shader_effect_set_uniform (shader, "fade_offset_bottom", G_TYPE_FLOAT, 1, ABS 
(self->fade_margins.bottom));