lottie: added intial documentation in the animation interface.

Change-Id: I92d802aa44492cdc83d15c8775dd8830f2cffe9d

diff --git a/inc/lottieanimation.h b/inc/lottieanimation.h
index ce163b9..b75019d 100644 (file)
--- a/inc/lottieanimation.h
+++ b/inc/lottieanimation.h
@@ -34,13 +34,50 @@ namespace lottie {
 
 class LOT_EXPORT Surface {
 public:
-    Surface() = default;
+    /**
+     *  @brief Surface object constructor.
+     *
+     *  @param[in] buffer surface buffer.
+     *  @param[in] width  surface width.
+     *  @param[in] height  surface height.
+     *  @param[in] bytesPerLine  number of bytes in a surface scanline.
+     *
+     *  @note Default surface format is ARGB32_Premultiplied.
+     */
     Surface(uint32_t *buffer, size_t width, size_t height, size_t bytesPerLine);
+
+    /**
+     *  @brief Returns width of the surface.
+     *
+     *  @return surface width
+     */
     size_t width() const {return mWidth;}
+
+    /**
+     *  @brief Returns height of the surface.
+     *
+     *  @return surface height
+     */
     size_t height() const {return mHeight;}
+
+    /**
+     *  @brief Returns number of bytes in the surface scanline.
+     *
+     *  @return number of bytes in scanline.
+     */
     size_t  bytesPerLine() const {return mBytesPerLine;}
+
+    /**
+     *  @brief Returns buffer attached tp the surface.
+     *
+     *  @return buffer attaced to the Surface.
+     */
     uint32_t *buffer() const {return mBuffer;}
 
+    /**
+     *  @brief Default constructor.
+     */
+    Surface() = default;
 private:
     uint32_t    *mBuffer;
     size_t       mWidth;
@@ -51,28 +88,141 @@ private:
 class LOT_EXPORT Animation {
 public:
 
+    /**
+     *  @brief Constructs an animation object from filepath.
+     *
+     *  @param[in] path Lottie resource file path
+     *
+     *  @return Animation object that can render the contents of the
+     *          lottie resource represented by file path.
+     */
     static std::unique_ptr<Animation>
     loadFromFile(const std::string &path);
 
+    /**
+     *  @brief Constructs an animation object from json string data.
+     *
+     *  @param[in] jsonData The JSON string data.
+     *  @param[in] key the string that will be used to cache the JSON string data.
+     *
+     *  @return Animation object that can render the contents of the
+     *          lottie resource represented by JSON string data.
+     */
     static std::unique_ptr<Animation>
     loadFromData(const char *jsonData, const char *key);
 
+    /**
+     *  @brief Returns default framerate of the lottie resource.
+     *
+     *  @return framerate of the lottie resource
+     *
+     */
     double frameRate() const;
+
+    /**
+     *  @brief Returns total number of frames present in the  lottie resource.
+     *
+     *  @return frame count of the lottie resource.
+     *
+     *  @note frame number starts with 0.
+     */
     size_t totalFrame() const;
+
+    /**
+     *  @brief Returns default viewport size of the lottie resource.
+     *
+     *  @param[out] width  default width of the viewport.
+     *  @param[out] height default height of the viewport.
+     *
+     */
     void   size(size_t &width, size_t &height) const;
+
+    /**
+     *  @brief Returns total animation duration of lottie resource in second.
+     *         it uses totalFrame() and frameRate() to calcualte the duration.
+     *         duration = totalFrame() / frameRate().
+     *
+     *  @return total animation duration in second.
+     *  @retval 0 if the lottie resource has no animation.
+     *
+     *  @see totalFrame()
+     *  @see frameRate()
+     */
     double duration() const;
+
+    /**
+     *  @brief Returns frame number for a given position.
+     *         this function helps to map the position value retuned
+     *         by the animator to a frame number in side the lottie resource.
+     *         frame_number = lerp(start_frame, endframe, pos);
+     *
+     *  @param[in] pos normalized position value [0 ... 1]
+     *
+     *  @return frame numer maps to the position value [startFrame .... endFrame]
+     *
+     */
     size_t frameAtPos(double pos);
 
+    /**
+     *  @brief Renders the content to surface Asynchronously.
+     *         it gives a future in return to get the result of the
+     *         rendering at a future point.
+     *         To get best performance user has to start rendering as soon as
+     *         it finds that content at {frameNo} has to be rendered and get the
+     *         result from the future at the last moment when the surface is needed
+     *         to draw into the screen.
+     *
+     *
+     *  @param[in] frameNo Content corresponds to the frameno needs to be drawn
+     *  @param[in] surface Surface in which content will be drawn
+     *
+     *  @return future that will hold the result when rendering finished.
+     *
+     *  for Synchronus rendering @see renderSync
+     *  @see Surface
+     */
     std::future<Surface> render(size_t frameNo, Surface surface);
+
+    /**
+     *  @brief Renders the content to surface synchronously.
+     *         for performance use the asyn rendering @see render
+     *
+     *  @param[in] frameNo Content corresponds to the frameno needs to be drawn
+     *  @param[in] surface Surface in which content will be drawn
+     */
     void              renderSync(size_t frameNo, Surface surface);
 
+    /**
+     *  @brief Returns list of rendering nodes that that represents the
+     *         content of the lottie resource at frame number {frameNo}.
+     *
+     *  @param[in] frameNo Content corresponds to the frameno needs to be extracted.
+     *  @param[in] width   content viewbox width
+     *  @param[in] height  content viewbox height
+     *
+     *  @return render node list.
+     */
+    const std::vector<LOTNode *> &renderList(size_t frameNo, size_t width, size_t height) const;
+
+    /**
+     *  @brief default destructor
+     */
     ~Animation();
-    Animation();
 
-    const std::vector<LOTNode *> &renderList(size_t frameNo, size_t width, size_t height) const;
+    /**
+     *  @brief default constructor
+     *
+     *  @note user should never construct animation object.
+     *         they should call the one of the factory method instead.
+     *
+     *  @see loadFromFile()
+     *  @see loadFromData()
+     */
+    Animation();
 private:
     std::unique_ptr<AnimationImpl> d;
 };
+
 }  // namespace lotplayer
 
 #endif  // _LOTTIE_ANIMATION_H_