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raycastlib.h

@@ -154,9 +154,19 @@ typedef struct
   It should return a characteristic of given square as an integer (e.g. square
   height, texture index, ...) - between squares that return different numbers
   there is considered to be a collision.
+
+  This function should be as fast as possible as it will typically be called
+  very often.
 */ 
 typedef Unit (*ArrayFunction)(int16_t x, int16_t y);
 
+/**
+  Function that renders a single pixel at the display. It is handed an info
+  about the pixel it should draw.
+
+  This function should be as fast as possible as it will typically be called
+  very often.
+*/
 typedef void (*PixelFunction)(PixelInfo info);
 
 typedef void
@@ -180,7 +190,15 @@ void castRayMultiHit(Ray ray, ArrayFunction arrayFunc, ArrayFunction typeFunc,
   HitResult *hitResults, uint16_t *hitResultsLen, RayConstraints constraints);
 
 Vector2D angleToDirection(Unit angle);
+
+/**
+Cos function.
+
+@param input to cos in Units (UNITS_PER_SQUARE = 2 * pi = 360 degrees)
+@return normalized output in Units (from -UNITS_PER_SQUARE to UNITS_PER_SQUARE)
+*/
 Unit cosInt(Unit input);
+
 Unit sinInt(Unit input);
 
 /// Normalizes given vector to have UNITS_PER_SQUARE length.
@@ -226,6 +244,22 @@ void render(Camera cam, ArrayFunction floorHeightFunc,
   ArrayFunction ceilingHeightFunc, ArrayFunction typeFunction,
   PixelFunction pixelFunc, RayConstraints constraints);
 
+/**
+  Function that moves given camera and makes it collide with walls and
+  potentially also floor and ceilings. It's meant to help implement player
+  movement.
+
+  @param camera camera to move
+  @param planeOffset offset to move the camera in
+  @param heightOffset height offset to move the camera in
+  @param floorHeightFunc function used to retrieve the floor height
+  @param ceilingHeightFunc function for retrieving ceiling height, can be 0
+                           (camera won't collide with ceiling)
+  @param computeHeight whether to compute height - if false (0), floor and
+                       ceiling functions won't be used and the camera will
+                       only collide horizontally with walls (good for simpler
+                       game, also faster)
+*/
 void moveCameraWithCollision(Camera *camera, Vector2D planeOffset,
   Unit heightOffset, ArrayFunction floorHeightFunc,
   ArrayFunction ceilingHeightFunc, int8_t computeHeight);