1 files changed, 77 insertions, 0 deletions
diff --git a/src/st/st-scroll-view-fade.glsl b/src/st/st-scroll-view-fade.glsl
new file mode 100644
index 0000000..ba6582f
--- /dev/null
+++ b/src/st/st-scroll-view-fade.glsl
@@ -0,0 +1,77 @@
+/*
+ * st-scroll-view-fade.glsl: Edge fade effect for StScrollView
+ *
+ * Copyright 2010 Intel Corporation.
+ * Copyright 2011 Adel Gadllah
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU Lesser General Public License,
+ * version 2.1, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+uniform sampler2D tex;
+uniform float height;
+uniform float width;
+uniform float fade_offset_top;
+uniform float fade_offset_bottom;
+uniform float fade_offset_left;
+uniform float fade_offset_right;
+uniform bool  fade_edges_top;
+uniform bool  fade_edges_right;
+uniform bool  fade_edges_bottom;
+uniform bool  fade_edges_left;
+uniform bool  extend_fade_area;
+
+uniform vec2 fade_area_topleft;
+uniform vec2 fade_area_bottomright;
+
+void main ()
+{
+    cogl_color_out = cogl_color_in * texture2D (tex, vec2 (cogl_tex_coord_in[0].xy));
+
+    float y = height * cogl_tex_coord_in[0].y;
+    float x = width * cogl_tex_coord_in[0].x;
+    float ratio = 1.0;
+
+    if (x > fade_area_topleft[0] && x < fade_area_bottomright[0] &&
+        y > fade_area_topleft[1] && y < fade_area_bottomright[1])
+    {
+        float after_left = x - fade_area_topleft[0];
+        float before_right = fade_area_bottomright[0] - x;
+        float after_top = y - fade_area_topleft[1];
+        float before_bottom = fade_area_bottomright[1] - y;
+
+        if (after_top < fade_offset_top && fade_edges_top) {
+            ratio *= after_top / fade_offset_top;
+        }
+
+        if (before_bottom < fade_offset_bottom && fade_edges_bottom) {
+            ratio *= before_bottom / fade_offset_bottom;
+        }
+
+        if (after_left < fade_offset_left && fade_edges_left) {
+            ratio *= after_left / fade_offset_left;
+        }
+
+        if (before_right < fade_offset_right && fade_edges_right) {
+            ratio *= before_right / fade_offset_right;
+        }
+    } else if (extend_fade_area) {
+        if (x <= fade_area_topleft[0] && fade_edges_left ||
+            x >= fade_area_bottomright[0] && fade_edges_right ||
+            y <= fade_area_topleft[1] && fade_edges_top ||
+            y >= fade_area_bottomright[1] && fade_edges_bottom) {
+            ratio = 0.0;
+        }
+    }
+
+    cogl_color_out *= ratio;
+}