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# I have searched and troubled but still no luck

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I have read almost every post on timing and have tried lots of different solutions with no luck. My problem I am done with my breakout clone and have been testing it out. I don't lock my frames rate because I end up having to move the ball too many pixels on slow machines, to have good game speed which ends up looking choppy. So I use the method of finding TimeDelta and using that along with velocity to update the speed. The problem I am having is that the speed changes on different machines. Another thing is that for it to be payable not to fast on my machine I end putting the velocity at 1 or .4 etc Here is where I get Timedelta which I call LastFrameTime
	FrameTime = timeGetTime();
LastFrameTime = timeGetTime();

while(Msg.message!=WM_QUIT && g_mES.isEmpty()==FALSE)
{
FrameTime = (float)timeGetTime();

if(PeekMessage(&Msg,NULL,0,0,PM_REMOVE)) {
TranslateMessage(&Msg);
DispatchMessage(&Msg);
}else {
g_mES.Process();													//process top engine

}
LastFrameTime =(float) timeGetTime() - FrameTime;
}


Any problems with that? Here is how I update the paddle


The only time my ball's x and y velocitys change speed is when they hit the paddle other wise they just get flipped if they hit somthing, so I use time delta only here and not every time the ball moves

balls[i]->X_velocity=  balls[i]->velocity * (cos(balls[0]->angle)* (LastFrameTime * 1.0f));				//change x's and y's velocity

balls[i]->Y_velocity=  balls[i]->velocity * (sin(balls[0]->angle)* (LastFrameTime * 1.0f));
balls[i]->loc.x =(float) balls[i]->loc.x + balls[i]->X_velocity;				//update the balls location

balls[i]->loc.y =(float) balls[i]->loc.y + balls[i]->Y_velocity;				//and return


Sorry for the long post but I wanted to make sure there was enough info, I am pulling what hair I have left out. thanks for your help -Marc [edited by - dapeos on April 22, 2004 5:51:08 AM]

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Ok, the typical format for something like this would be as follows.

float mCurrentTime;float mPreviousTime;float mDelta;/*MAIN LOOP BEGIN*/while (gameloop == true){    // get the current time     mCurrentTime = TimeGetTime();    // calculate the time elapsed since the previous frame    float mDelta = mPreviousTime - mCurrentTime;    // do all update of sprites etc     // using mDelta (the time that     // has passed since the last frame)    mPlayer.locationx += (speed * mDelta);    //record the time of the frame we just did as the previous    mPreviousTime = mCurrentTime;}/*MAIN LOOP END*/

Be aware, that is a rough guide and not complete code. Furthermore your first mDelta value could be screwy as the mPrevious will not have been set. That can be counteracted with a quick call of mPreviousTime = TimeGetTime() before you enter that main loop.

Edit: typo and tidy

[edited by - ghosted on April 22, 2004 7:15:44 AM]

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float mCurrentTime;float mPreviousTime;float mDelta;float padvel = 0;float ballxvel = 0;float vallyvel = 0;float padspeed = 100; //pixels a second/*MAIN LOOP BEGIN*/while (gameloop == true){    // get the current time     mCurrentTime = TimeGetTime();    // calculate the time elapsed since the previous frame    float mDelta = mPreviousTime - mCurrentTime; //in ms    mDelta /= 1000; //in seconds    //record the time of the frame we just did as the previous    mPreviousTime = mCurrentTime;    if (gotpowerup)       padspeed += 50;    if (moveleft)        padvel = -padspeed    else if (moveright)        padvel = padspeed;    else         padvel = 0;    padx += padvel * mDelta; // pix per second * number of seconds                              //thats past is the number of pixels its moved.    DrawPad(padx);    GetInput();    }/*MAIN LOOP END*/

You just have to understand timing, before you can make a timer. I hope I dind''t misunderstand and annoy you with things you do know.

//Base code complements of ghosted.

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No not at all I thank you for the help, I have never touched on timers before so I eat up your info. Seems like what I was doing wrong was not dividing TimeDelta by 1000 stupid me.
It seems to work now haven''t tried it yet on another machine, but its not as smooth as it was when I just moving it 1 pixel at a time
the problem was slower comps couldn''t keep up.
So I want the paddle to make it across the sceen in 3 seconds I would use move 1280/3 = 427 to times against delta right?
that works and the paddle makes it across the screen in three but it is kindof jerky not bad but not great ether any ideas?
-Marc

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What is vsync(or what ever its called) all about?

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Still goes incredibly slow on roomates comp shouldn''t it look just choppy if his comp can''t run it but still be the same speed?

WinMain:
int WINAPI WinMain(HINSTANCE hInstance,HINSTANCE hPrevInst,LPSTR lpCmdLine,int nShowCmd)	{	g_hInst=hInstance;	if(Init()==FALSE)		ShutDown();	cMenuEng *mMenuEng= new cMenuEng();											//create a menu engine	g_mES.Push(mMenuEng);														//push it 	LastFrameTime = timeGetTime();		while(Msg.message!=WM_QUIT && g_mES.isEmpty()==FALSE)			{		FrameTime = (float)timeGetTime();		DeltaTime =(float) LastFrameTime - FrameTime;		DeltaTime = DeltaTime / 1000 * -1;		if(PeekMessage(&Msg,NULL,0,0,PM_REMOVE)) {			TranslateMessage(&Msg);			DispatchMessage(&Msg);		}else {			g_mES.Process();													//process top engine			}		LastFrameTime = FrameTime;		}	ShutDown();															//shutdown game	return(Msg.wParam);																	}

handle input:

void cGameEng::HandleInput()	{			g_mDI.ReadKey();			if(KeyState(DIK_LEFT) && pad->loc.x >= 25 ){					//move paddle left				if(balls[0]->velocity==0)						balls[0]->loc.x = (float) balls[0]->loc.x - (640 * (DeltaTime));				pad->loc.x = (float) pad->loc.x -(640 * (DeltaTime));				}			if(KeyState(DIK_RIGHT)&& (pad->loc.x +pad->width) <= 1255){		//move paddle right				if(balls[0]->velocity==0)						balls[0]->loc.x = (float) balls[0]->loc.x+ (640 * (DeltaTime));				pad->loc.x =(float)  pad->loc.x + (640 * (DeltaTime)); 				}					if((balls[0]->Y_velocity==0) && KeyState(DIK_SPACE))				//launch ball				balls[0]->velocity = 200;							if(KeyState(DIK_ESCAPE)){										//exit game					ShowCursor(TRUE);				g_mES.Pop();				}	}

update ball collision dectection etc:
	for(int i=0; i<3; i++){			if(balls[i]->active==TRUE){				if((balls[i]->loc.y + balls[i]->height) >= pad->loc.y &&							//check to see if ball hit paddle					balls[i]->loc.x + balls[i]->width >= pad->loc.x &&					balls[i]->loc.x <= pad->loc.x + pad->width &&					balls[i]->loc.y + balls[i]->height < pad->loc.y + pad->height)					{										double centerPad  = pad->loc.x + pad->width/2;					double dfc		  = balls[i]->center.x - centerPad;					dfc				  = dfc * .83;																			double angle	  = 90 - dfc;					balls[i]->angle		  = (angle * 3.14)/180;					balls[i]->angle		  = balls[i]->angle * -1;															//negate the angle					balls[i]->X_velocity=  balls[i]->velocity * (cos(balls[0]->angle)* (DeltaTime));				//change x''s and y''s velocity					balls[i]->Y_velocity=  balls[i]->velocity * (sin(balls[0]->angle)* (DeltaTime));										if(balls[i]->velocity!=0)														//play bounce sound									g_mDS.sound_fx[g_mDS.sound_pad_hit].dsbuffer->Play(0,0,0);												balls[i]->loc.x =(float) balls[i]->loc.x + balls[i]->X_velocity;				//update the balls location					balls[i]->loc.y =(float) balls[i]->loc.y + balls[i]->Y_velocity;				//and return					return;					}				int hit	= mBM->collide(balls[i]);				if(hit!=0){																			//hit a block					g_mDS.sound_fx[g_mDS.sound_bounce].dsbuffer->Play(0,0,0);						//play sound											if(hit == 1)						balls[i]->Y_velocity = 	balls[i]->Y_velocity * -1;					else if (hit == 2)						balls[i]->X_velocity = 	balls[i]->X_velocity * -1;										balls[i]->loc.x =(float) balls[i]->loc.x + balls[i]->X_velocity;				//update the balls location					balls[i]->loc.y =(float) balls[i]->loc.y + balls[i]->Y_velocity;				//and return					return;					}				if(balls[i]->loc.y  <= 25)															//check borders					balls[i]->Y_velocity = 	balls[i]->Y_velocity * -1;				else if(balls[i]->loc.x <= 25)					balls[i]->X_velocity = 	balls[i]->X_velocity * -1;				else if(balls[i]->loc.x + balls[0]->width >= 1255)					balls[i]->X_velocity = 	balls[i]->X_velocity * -1;				balls[i]->loc.x =(float) balls[i]->loc.x + balls[i]->X_velocity;					//update the balls location				balls[i]->loc.y =(float) balls[i]->loc.y + balls[i]->Y_velocity;				if(	balls[i]->loc.y >1024)															//ball fell thru					balls[i]->active = FALSE;				if(balls[0]->active==FALSE && balls[1]->active==FALSE && balls[2]->active==FALSE)	//are all balls gone					reset();									}			}

Any ideas?
thanks again
-Marc

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quote:
Original post by dapeos
What is vsync(or what ever its called) all about?

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thanks alot arkitek, did you not read the title of the post?
Why even take the time to reply if your only purpose is to be a dick?
my thoughts anyways
-Marc

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The jerkyness is showing you the difference in the delta time''s. There are ways to limit the difference and catch back up in later frames. Search on higher resolution timers and see if you have a big function that gets called every so often providing a jerk. The faster you move and the longer the delta time''s determines the jerky level. Slow it (the paddle) down or speed you game up and it will solve it.

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