Code re-work: shadow mapping.

src/5.advanced_lighting/3.2.1.point_shadows/3.2.1.point_shadows_depth.fs

@@ -0,0 +1,16 @@
+#version 330 core
+in vec4 FragPos;
+
+uniform vec3 lightPos;
+uniform float far_plane;
+
+void main()
+{
+    float lightDistance = length(FragPos.xyz - lightPos);
+    
+    // map to [0;1] range by dividing by far_plane
+    lightDistance = lightDistance / far_plane;
+    
+    // write this as modified depth
+    gl_FragDepth = lightDistance;
+}