Book Image

Android NDK: Beginner's Guide

By : Sylvain Ratabouil
Book Image

Android NDK: Beginner's Guide

By: Sylvain Ratabouil

Overview of this book

Table of Contents (18 chapters)
Android NDK Beginner's Guide Second Edition
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Time for action – animating graphics with a timer


Let's animate the game.

  1. Create jni/TimeManager.hpp with the time.h manager and define the following methods:

    • reset() to initialize the manager.

    • update() to measure game step duration.

    • elapsed() and elapsedTotal() to get game step duration and game duration. They are going to allow the adaptation of the application behavior to the device speed.

    • now() is a utility method to recompute the current time.

    Define the following member variables:

    • mFirstTime and mLastTime to save a time checkpoint in order to compute elapsed() and elapsedTotal()

    • mElapsed and mElapsedTotal to save computed time measures

      #ifndef _PACKT_TIMEMANAGER_HPP_
      #define _PACKT_TIMEMANAGER_HPP_
      
      #include "Types.hpp"
      
      #include <ctime>
      
      class TimeManager {
      public:
          TimeManager();
      
          void reset();
          void update();
      
          double now();
          float elapsed() { return mElapsed; };
          float elapsedTotal() { return mElapsedTotal; };
      
      private:
          double mFirstTime;
          double mLastTime...