From: Florian Müllner <fmuellner@gnome.org>
Date: Sat, 23 Feb 2013 00:37:05 +0000 (+0100)
Subject: scroll-view-fade: Tweak easing at edges
X-Git-Tag: archive/raspbian/50.5-1+rpi1~1^2~1013^2^2~4616
X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/%22/%22http:/www.example.com/cgi/%22?a=commitdiff_plain;h=b394d184cc7fa68924da7e4c57ba9d2eb84c97ef;p=gnome-shell.git

scroll-view-fade: Tweak easing at edges

Since commit b4f5f1e46174, the effect is eased in at the scroll
view's edges so that it does not appear out of nowhere. However,
the linear easing used is not the best option, as now the effect
appears so late that content near the edges ends up just being
cut off rather than faded out.
So adjust the easing function to have the effect appear faster.

https://bugzilla.gnome.org/show_bug.cgi?id=694327
---

diff --git a/src/st/st-scroll-view-fade.glsl b/src/st/st-scroll-view-fade.glsl
index 6acd26000..e8bd03a2a 100644
--- a/src/st/st-scroll-view-fade.glsl
+++ b/src/st/st-scroll-view-fade.glsl
@@ -64,20 +64,20 @@ void main ()
 
     float vfade_scale = height / vfade_offset;
     if (fade_top) {
-        ratio *= FADE((y / vfade_offset), min(vvalue * vfade_scale, 1.0));
+        ratio *= FADE((y / vfade_offset), min(sqrt(vvalue) * vfade_scale, 1.0));
     }
 
     if (fade_bottom) {
-        ratio *= FADE((fade_area[1][1] - y)/(fade_area[1][1] - fade_bottom_start), min((1.0 - vvalue) * vfade_scale, 1.0));
+        ratio *= FADE((fade_area[1][1] - y)/(fade_area[1][1] - fade_bottom_start), min(sqrt(1.0 - vvalue) * vfade_scale, 1.0));
     }
 
     float hfade_scale = width / hfade_offset;
     if (fade_left) {
-        ratio *= FADE(x / hfade_offset, min(hvalue * hfade_scale, 1.0));
+        ratio *= FADE(x / hfade_offset, min(sqrt(hvalue) * hfade_scale, 1.0));
     }
 
     if (fade_right) {
-        ratio *= FADE((fade_area[1][0] - x)/(fade_area[1][0] - fade_right_start), min((1.0 - hvalue) * hfade_scale, 1.0));
+        ratio *= FADE((fade_area[1][0] - x)/(fade_area[1][0] - fade_right_start), min(sqrt(1.0 - hvalue) * hfade_scale, 1.0));
     }
 
     cogl_color_out *= ratio;