In response to all the requests for a way to calculate FPS I hereby give you a fully working nice and simple Speedometer class. ---------------------------------------------- FILE:Speedometer.h ---------------------------------------------- ////////////////////////////////////////////////////////////////////// // // Author: Tristan "WytRaven" Ward 2000 // Speedometer.h: interface for the CSpeedometer class. // Requires links to winmm.lib, dxguid.lib, ddraw.lib // ////////////////////////////////////////////////////////////////////// #if !defined(AFX_SPEEDOMETER_H__571FE742_F39D_11D3_8BE4_92DC7A4C1216__INCLUDED_) #define AFX_SPEEDOMETER_H__571FE742_F39D_11D3_8BE4_92DC7A4C1216__INCLUDED_ #if _MSC_VER >= 1000 #pragma once #endif // _MSC_VER >= 1000 class CSpeedometer { public: CSpeedometer(); virtual ~CSpeedometer(); void Update(); void Report(LPDIRECTDRAWSURFACE7 pDDS, int xpos, int ypos); private: int StartFrameCount; int FrameCount; int FrameRate; DWORD EndTime; DWORD StartTime; }; #endif // !defined(AFX_SPEEDOMETER_H__571FE742_F39D_11D3_8BE4_92DC7A4C1216__INCLUDED_) ---------------------------------------------- FILE:Speedometer.cpp ---------------------------------------------- ////////////////////////////////////////////////////////////////////// // // Author: Tristan "WytRaven" Ward 2000 // Speedometer.cpp: implementation of the CSpeedometer class. // Requires links to winmm.lib, dxguid.lib, ddraw.lib // ////////////////////////////////////////////////////////////////////// #include #include #include #include #include "Speedometer.h" ////////////////////////////////////////////////////////////////////// // Construction/Destruction ////////////////////////////////////////////////////////////////////// CSpeedometer::CSpeedometer() { StartTime = timeGetTime(); EndTime = StartTime; StartFrameCount = 0; FrameCount = 0; FrameRate = 0; } CSpeedometer::~CSpeedometer() { } // Print current FPS to chosen surface void CSpeedometer::Report(LPDIRECTDRAWSURFACE7 pDDS, int xpos, int ypos) { HDC hdc; char pString[30]; sprintf(pString,"FPS : %d", FrameRate); pDDS->GetDC(&hdc); SetBkMode(hdc, OPAQUE); SetTextColor(hdc, 0x000000); TextOut(hdc, xpos, ypos, pString, strlen(pString)); pDDS->ReleaseDC(hdc); } // Calculate FPS void CSpeedometer::Update() { EndTime = timeGetTime(); if (EndTime - StartTime > 1000) { FrameRate = (FrameCount - StartFrameCount) * 1000 / (EndTime - StartTime); StartTime = EndTime; StartFrameCount = FrameCount; } FrameCount++; } To use just place a call to the Report method in your renderer and a call to the Update method in your message loop. Enjoy. Please feel free to make any comments on how you like/dislike this but please refrain from commenting unless youve acctually tried it. wytraven@kik.net

Sorry the board screwed up my includes, they should be as follows:

#include >windows.h<
#include >mmsystem.h<
#include >ddraw.h<
#include >stdio.h<
#include "Speedometer.h"

><'s are reversed to trick the board

I would also like to point out that I am a newbie to both C++ and DirectX, I am teaching myself about both so I don't claim that this is the ultimate way to go about this and I would be gratefull for any pointers to things that could be improved. Thanks.



wytraven@kik.net

Edited by - WytRaven on 3/6/00 6:01:15 PM

why bother creating a class for this? are you going to be creating many FPS objects? that seems like a lot of work just to calculate the framerate. i do it in about four or five lines in my engine...


_________________Gecko___
Gecko Design

uhh, call me stupid, but I didn''t quite understand it. Maybe I''m just tired. Anyway the part I didn''t understand was this:


// Calculate FPS
void CSpeedometer::Update()
{
EndTime = timeGetTime();
if (EndTime - StartTime > 1000)
{
FrameRate = (FrameCount - StartFrameCount) * 1000 / (EndTime - StartTime);
StartTime = EndTime;
StartFrameCount = FrameCount;
}
FrameCount++;
}


If anyone could explain this for me, I would be very greatful!

"Remember, I'm the monkey, and you're the cheese grater. So no fooling around."
-Grand Theft Auto, London

void CSpeedometer::Update()
{
//Get current time
EndTime = timeGetTime();
//1000 milliseconds == 1 second, so see if one second has
//elapsed since last time we checked (StartTime)
if (EndTime - StartTime > 1000)
{
//if one second has gone by, find out how many frames we have
//rendered in that second
FrameRate = (FrameCount - StartFrameCount) * 1000 / (EndTime - StartTime);
//reset StartTime for the next update
StartTime = EndTime;
//reset StartFrameCount for the next update
StartFrameCount = FrameCount;
}
//Add another frame
FrameCount++;
}



_________________Gecko___
Gecko Design

Thanks for adding in the comments Gecko, I really should learn to comment my code shouldn''t I

There are 2 reasons I choose to use a class:

1. It''s nice and neat and easy to add to any project.
2. Because I am new to C++ and wanted to get practice making classes.

Good enough excuse?


wytraven@kik.net

Hi. I use the API to calculate the FPS. I always calculate it this way:

First you have to have four global variables:

LARGE_INTEGER Frequency,NewTime,LastTime;
double FPS;

Call

QueryPerformanceFrequency( &Frequency )

one time.

Then you always have to do like this in your Update - function or whatever you call it:

LastTime = NewTime;

QueryPerformanceTimer( &NewTime );

//FPS - calculation
FPS = (double)Frequency.QuadPart /
((double)NewTime.QuadPart - (double)LastTime.QuadPart);

Afterwards you''ve got the FPS in FPS.

But I''ve got a question, too:

How can I synchronize animations the right way if the FPS changes many times in a second.

Please tell me. I REALLY NEED HELP!!!!

my Mail: Centum@gmx.net

Thank you!