diff --git a/helloRay.cpp b/helloRay.cpp
index 974e60c..b29cd9f 100644
--- a/helloRay.cpp
+++ b/helloRay.cpp
@@ -10,7 +10,8 @@
      function that will render pixels. It allows super performance. */
 
 /* There are many other options that can be defined here, check the library
-   for details. */
+   for details. Don't forget to disable the features you won't be using - it
+   will speed up the rendering. */
 
 #include "raycastlib.h"
 #include "Pokitto.h"
@@ -20,26 +21,38 @@ Pokitto::Core pokitto;
 RCL_Camera camera; // Defines a view that will be rendered.
 RCL_RayConstraints constraints;
 
-// Function that for given square coordinates returns height of the floor.
+/* Function that for given square coordinates returns height of the floor
+   (in RCL_Units). */
 RCL_Unit floorHeightAt(int16_t x, int16_t y)
 {
   return x < 0 || x >= 10 || y < 0 || y >= 10 ?
     RCL_UNITS_PER_SQUARE * 2 : 0;
-    // ^ RCL_UNITS_PER_SQUARE is the length of one side of the game world square.
+    /* ^ RCL_UNITS_PER_SQUARE is the length of one side of the game square.
+         Since we'll place the camera at RCL_UNITS_PER_SQUARE height, let's
+         make the walls twice as high. */
+
+  /* You can either generate the level procedurally as above, or read it from
+     an array and return it here. */
 }
 
-// Function which the library will call to draw indivifual pixels.
+/* Function that will be called by the library in order to draw individual
+   pixels (similar to fragment shaders in OpenGL). */
+
 void pixelFunc(RCL_PixelInfo *pixel)
 {
   uint8_t color;
 
-  /* Pixel holds all kind of info about the pixel to be rendered. Check
-     the PixelInfo struct for details. */
+  /* The pixel variable holds all kind of info about the pixel to be rendered.
+     Check the PixelInfo struct for details. */
 
   if (pixel->isWall)
-    color = pixel->hit.direction + 2;
+    color = pixel->hit.direction + 2; // give walls different colors
   else
-    color = pixel->isFloor ? 10 : 11;
+    color = pixel->isFloor ? 10 : 11; // also make ceiling and floor differ
+
+  /* You can do all kinds of processing here and draw the pixel wherever you
+     want, or even discard it. Just remember this function has to be fast and
+     will usually be the bottleneck. */
 
   pokitto.display.drawPixel(pixel->position.x,pixel->position.y,color);
 }
@@ -48,6 +61,7 @@ void draw()
 {
   /* This triggers the rendering, which will keep calling pixelFunc to render
      the camera view. */
+
   RCL_renderSimple(camera,floorHeightAt,0,0,constraints);
 }
 
@@ -56,7 +70,8 @@ int main()
   pokitto.begin(); 
   pokitto.setFrameRate(60);
 
-  RCL_initCamera(&camera);
+  RCL_initCamera(&camera); /* To initialize all parameters so that none
+                              remains undefined. */
 
   // Set the camera position to square [4;6].
   camera.position.x = 4 * RCL_UNITS_PER_SQUARE;
@@ -69,15 +84,15 @@ int main()
   camera.resolution.y = 88;
 
   // This specifies the ray behavior.
-  constraints.maxHits = 1;
-  constraints.maxSteps = 20;
+  constraints.maxHits = 1;   // Stop at first intersection with a wall.
+  constraints.maxSteps = 20; // Trace maximum of 20 squares.
 
   while (pokitto.isRunning())
   {
     if (pokitto.update())
     {
       draw();
-      camera.direction -= 10; // Rotate camera for some animation.
+      camera.direction -= 10; // Rotate the camera for some animation.
     }
   }