Add a 'Ripple' transition

Change-Id: I18efe35c299bc3a4a2a5e449021323fc1f53f378

1 files changed, 33 insertions, 0 deletions

diff --git a/slideshow/opengl/rippleFragmentShader.glsl b/slideshow/opengl/rippleFragmentShader.glsl
new file mode 100644
index 000000000000..83677e4d6390
--- /dev/null
+++ b/slideshow/opengl/rippleFragmentShader.glsl
@@ -0,0 +1,33 @@
+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#define M_PI 3.1415926535897932384626433832795
+
+uniform sampler2D leavingSlideTexture;
+uniform sampler2D enteringSlideTexture;
+uniform float time;
+uniform vec2 center;
+varying vec2 v_texturePosition;
+
+void main()
+{
+    float d = length(v_texturePosition - center);
+    float w = 0;
+    w = max(w, length(center - vec2(0, 0)));
+    w = max(w, length(center - vec2(1, 0)));
+    w = max(w, length(center - vec2(1, 1)));
+    w = max(w, length(center - vec2(0, 1)));
+    float v = 0.2;
+    float smoothtime = smoothstep(0, 1, time);
+    float a = smoothstep(smoothtime*w-v, smoothtime*w+v, d);
+    a += (0.5 - abs(a-0.5))*sin(d*M_PI*30);
+    gl_FragColor = mix(texture2D(enteringSlideTexture, v_texturePosition), texture2D(leavingSlideTexture, v_texturePosition), a);
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */