My library

[RandomDever]

Code: Select all

if ((time/frame) < (1000/FPS))
		{
			SDL_Delay((1000/FPS) - (time/frame));
		}

What's wrong with this code?
It compiles and runs but it runs at 2 FPS even though I have the const int FPS = 1;

[short]

46 posts here. You have to try harder then this. /palmface

[MarauderIIC]

Code: Select all

if ((time/frame) < (1000/FPS))
		{
			SDL_Delay((1000/FPS) - (time/frame));
		}

What's wrong with this code?
It compiles and runs but it runs at 2 FPS even though I have the const int FPS = 1;

Let's plug in some values.

time = 500 (a half-second has passed since the start of the program)
frame = 1 (this is the first frame)

if (500/1 < 1000/1)
SDL_Delay((1000/1) - (500/1)) = SDL_Delay(500) = 1/2 second

So, a half-second has passed. And we're delaying a half-second. Hmmm... it could be that you draw before your delay is called, or that I'm making wrong assumptions about what each variable is.

[Pickzell]

Code: Select all

if ((time/frame) < (1000/FPS))
		{
			SDL_Delay((1000/FPS) - (time/frame));
		}

What's wrong with this code?
It compiles and runs but it runs at 2 FPS even though I have the const int FPS = 1;

Why are you dividing things by the FPS then... 1000/1 is 1000...

[MarauderIIC]

Why are you dividing things by the FPS then... 1000/1 is 1000...

...
Because maybe he wants to be able to change the FPS later. You know, one of the reasons you use a named constant in the first place?

[hurstshifter]

46 posts here. You have to try harder then this. /palmface

This

[RandomDever]

Code: Select all

#include "MSDL_image.h"
#include "MSDL_render.h"
#include "MSDL_ttf.h"
#include "MSDL_key.h"
#include "MSDL_timer.h"
#include "player.h"

SDL_Event event;

int count = 0;
Uint32 frame = 0;
bool quit = false;
Uint8 *keystates;
Uint32 time = 1;
char buffer[600];
char buffer2[600];

const int Width = 640;
const int Height = 480;
const int BPP = 32;

const Uint32 FPS = 1;

SDL_Surface *screen = NULL;
SDL_Surface *color = NULL;
SDL_Surface *background = NULL;
SDL_Surface *ground = NULL;
SDL_Surface *timer = NULL;
SDL_Surface *keys = NULL;
SDL_Surface *frames =NULL;

Player player;

void Init()
{

	SDL_Init( SDL_INIT_EVERYTHING );
	screen = SDL_SetVideoMode( Width, Height, BPP, SDL_SWSURFACE );
	SDL_WM_SetCaption( "SMB Clone v0.0.1", NULL );
	TTF_Init();
}

void Exit()
{
	SDL_Quit();
}

int main( int argc, char* args[] )
{
	Init();
	background = LoadKeyImage( "background.png", 0, 0, 255 );
	color = LoadImage( "color.png" );
	ground = LoadImage( "ground.png" );
	//, "arblanca.ttf", 140, 0, 0, 255
	BlitSurface( 0, 0, color, screen );
	BlitSurface( 0, 0, background, screen );
	//BlitSurface( (Width / 2) - (timer->w / 2), (Height / 2) - (timer->h / 2), timer, screen );
	while (count < 640)
	{
		BlitSurface( count, 448, ground, screen );
		count += 32;
	}
	RenderTextCenter( "Hello!", "comic.ttf", 140, 255, 0, 0, screen, Height, Width );
	SDL_Flip( screen );
	while( quit == false )
	{
		frame++;
		count = 0;
		time = SDL_GetTicks();
		BlitSurface( 400, 0, keys, screen );
		SDL_Flip( screen );
		keystates = Keystates();
		BlitSurface( 0, 0, color, screen );
		BlitSurface( 0, 0, background, screen );
		while (count < 640)
		{
			BlitSurface( count, 448, ground, screen );
			count += 32;
		}
		RenderTextCenter( "Hello!", "comic.ttf", 140, 255, 0, 0, screen, Height, Width );

		while( SDL_PollEvent( &event ) )
		{
			if( event.type == SDL_QUIT )
			{
				quit = true;
			}
		}
		sprintf_s(buffer,"Time: %d", time);
		timer = RenderText( buffer, "arberkley.ttf", 40, 0, 0, 255 );
		BlitSurface ( 0, 0, timer, screen );
		if( keystates[ SDLK_UP ] )
		{
			keys = RenderText( "UP", "comic.ttf", 40, 0, 0, 255  );
		} 
		if ((time/frame) < (1000/FPS))
		{
			SDL_Delay((1000/FPS) - (time/frame));
		}
		sprintf_s(buffer2,"frame: %d", frame);
		frames = RenderText( buffer2, "arberkley.ttf", 40, 0, 0, 255 );
		BlitSurface ( 0, 60, frames, screen );
		SDL_Flip( screen );
		//if ( frame == 1 )
		//{
		//	SDL_Delay( 5000 );
		//}
	}
	Exit();
	return 0;
}

There's the source code.
BTW my MSDL library for time is just returning SDL_GetTicks right now so that shouldn't be a problem.

[MarauderIIC]

Nothing jumps out as a problem. How are you telling how many frames happen per second? Maybe that's where the problem is.

[RandomDever]

Nothing jumps out as a problem. How are you telling how many frames happen per second? Maybe that's where the problem is.

i'm just using SDL_Delay()
It's all handled in the first snippet i posted
pretty much

[Moosader]

http://elysianshadows.com/phpBB3/viewto ... f=6&t=4079


:D !

[Scoody]

The framelimiter calculates how much time each frame has to its disposal, if it doesn't utilize all that time the rest is put in a delay.

Here you're just dividing the start time with the amount of frames that's been drawn, which makes no sense. You need to take the current ticks and subtract the ticks at the start; then you'll know how much time the current frame used to draw.

Code: Select all

 if ((time/frame) < (1000/FPS))
      {
         SDL_Delay((1000/FPS) - (time/frame));
      }

So (time/frame) should be (SDL_GetTicks() - time)

Code: Select all

Uint32 elapsed = SDL_GetTicks() - time;
 if (elapsed < (1000/FPS))
      {
         SDL_Delay((1000/FPS) - elapsed);
      }

[RandomDever]

The framelimiter calculates how much time each frame has to its disposal, if it doesn't utilize all that time the rest is put in a delay.

Here you're just dividing the start time with the amount of frames that's been drawn, which makes no sense. You need to take the current ticks and subtract the ticks at the start; then you'll know how much time the current frame used to draw.

Code: Select all

 if ((time/frame) < (1000/FPS))
      {
         SDL_Delay((1000/FPS) - (time/frame));
      }

So (time/frame) should be (SDL_GetTicks() - time)

Code: Select all

Uint32 elapsed = SDL_GetTicks() - time;
 if (elapsed < (1000/FPS))
      {
         SDL_Delay((1000/FPS) - elapsed);
      }

Ummmm.

time is SDL_GetTicks() so subtracting it from itself would mean 0 so it would delay 999 ms every frame.

[MarauderIIC]

No, time is the time that passed when you started making the frame. SDL_GetTicks() is the time that has passed until that very point.
But it might be effectively 0.