Solved

Portable Frame Rate Locker

Posted on 2006-11-14
5
465 Views
Last Modified: 2012-08-13
Hi!!

I've got a problem, I'm making a game in OpenGL using GLUT and it needs to be portable. The problem is that I want to be able to lock to a specific frame rate. I've got a function that does this but it uses GetTickCount() which is a Windows API function, is there a way to make this portable.

Thanks a lot in advance!!

G
0
Comment
Question by:gabzuka
  • 3
  • 2
5 Comments
 
LVL 45

Accepted Solution

by:
sunnycoder earned 500 total points
ID: 17945287
Hi gabzuka,

gettimeofday is fairly portable - POSIX defined - but windows is not POSIX complaint...

If you can compromise on resolution - time() would be fairly portable since it is defined by ANSI .. complete set of ANSI C time functions
http://www.csse.uwa.edu.au/programming/ansic-library.html#time

Else, you can opt for code like
#ifdef WIN32
GetTickCount()
#endif
#ifdef LINUX
gettimeofday()
#endif

Cheers!
sunnycoder
0
 

Author Comment

by:gabzuka
ID: 17950489
The time() function returns seconds and since I need frames per second is not the best option, nonetheless I tried using it with something like this, but it doesn't seem to work:

bool LockFrameRate(int frame_rate)
{
      static int lastTime;
      static int cont = 0;

      time_t tiempo;
      time(&tiempo);
      int currentTime = tiempo;

      if(currentTime == lastTime && cont>=frame_rate)
      {
            return false;
      }
      else if(currentTime == lastTime)
      {
            cont++;
            return true;
      }
      else
      {
            cont = 0;
            lastTime = currentTime;
            return true;
      }
      return false;
}

I think my best bet would be to use the #ifdef WIN32 ... but one more thing, I need it to run on Windows and Mac, does gettimeofday() work in Mac the same way GetTickCount() does in Win32?
0
 

Author Comment

by:gabzuka
ID: 17950497
The time() function returns seconds and since I need frames per second is not the best option, nonetheless I tried using it with something like this, but it doesn't seem to work:

bool LockFrameRate(int frame_rate)
{
      static int lastTime;
      static int cont = 0;

      time_t tiempo;
      time(&tiempo);
      int currentTime = tiempo;

      if(currentTime == lastTime && cont>=frame_rate)
      {
            return false;
      }
      else if(currentTime == lastTime)
      {
            cont++;
            return true;
      }
      else
      {
            cont = 0;
            lastTime = currentTime;
            return true;
      }
      return false;
}

I think my best bet would be to use the #ifdef WIN32 ... but one more thing, I need it to run on Windows and Mac, does gettimeofday() work in Mac the same way GetTickCount() does in Win32?
0
 
LVL 45

Expert Comment

by:sunnycoder
ID: 17953713
>int currentTime = tiempo;
why did you have to cast time_t to int??? This is likely to result in loss of data and incorrect results

>The time() function returns seconds and since I need frames per second is not the best option
You are right with this ... time() gives you one second resolution, so you cannot take a decision for subsecond intervals.

>does gettimeofday() work in Mac the same way GetTickCount() does in Win32?
I am not much familiar with Mac programming ... If Mac is POSIX compliant, gettimeofday would work ... gettimeofday has microsecond resolution
http://www.die.net/doc/linux/man/man2/gettimeofday.2.html
0
 

Author Comment

by:gabzuka
ID: 17955432
I'll use gettimeofday then ... thanks a lot!!!
G
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Is javax.swing good enough for pro quality RTS? 4 182
Doesn't seem logical 8 231
Can anybody center this unfinished Death Star for me? 6 152
hasOne  challenge 59 126
Artificial Intelligence comes in many forms, and for game developers, Path-Finding is an important ability for making an NPC (Non-Playable Character) maneuver through terrain.  A* is a particularly easy way to approach it.  I’ll start with the algor…
As game developers, we quickly learn that Artificial Intelligence (AI) doesn’t need to be so tough.  To reference Space Ghost: “Moltar, I have a giant brain that is able to reduce any complex machine into a simple yes or no answer. (http://www.youtu…
Migrating to Microsoft Office 365 is becoming increasingly popular for organizations both large and small. If you have made the leap to Microsoft’s cloud platform, you know that you will need to create a corporate email signature for your Office 365…
Hi friends,  in this video  I'll show you how new windows 10 user can learn the using of windows 10. Thank you.

864 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

22 Experts available now in Live!

Get 1:1 Help Now