1 files changed, 49 insertions, 0 deletions
diff --git a/examples/qt3d/wave/shaders/ribbon.frag b/examples/qt3d/wave/shaders/ribbon.frag
new file mode 100644
index 000000000..09ad78871
--- /dev/null
+++ b/examples/qt3d/wave/shaders/ribbon.frag
@@ -0,0 +1,49 @@
+#version 330 core
+
+in EyeSpaceVertex {
+    vec3 position;
+    vec3 normal;
+} fs_in;
+
+out vec4 fragColor;
+
+uniform struct LightInfo {
+    vec4 position;
+    vec3 intensity;
+} light;
+
+uniform struct LineInfo {
+    float width;
+    vec4 color;
+} line;
+
+uniform vec3 ka;            // Ambient reflectivity
+uniform vec3 kd;            // Diffuse reflectivity
+
+vec3 rimLightModel( const in vec3 pos, const in vec3 n )
+{
+    // Calculate the vector from the light to the fragment
+    vec3 s = normalize( vec3( light.position ) - pos );
+
+    // Calculate the vector from the fragment to the eye position (the
+    // origin since this is in "eye" or "camera" space
+    vec3 v = normalize( -pos );
+
+    // Refleft the light beam using the normal at this fragment
+    vec3 r = reflect( -s, n );
+
+    // Calculate the diffuse component, which for rim lighting it 1 minus s dot n
+    // rather than s dot n as for standard diffuse lighting
+    float sDotN = dot( s, n );
+    vec3 diffuse = vec3( 1.0 - max( sDotN, 0.0 ) );
+
+    // Combine the ambient, diffuse and specular contributions
+    return light.intensity * ( ka + kd * diffuse );
+}
+
+void main()
+{
+    vec3 n = gl_FrontFacing ? fs_in.normal : -fs_in.normal;
+    vec4 color = vec4( rimLightModel( fs_in.position, normalize( n ) ), 1.0 );
+    fragColor = color;
+}