common.c
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/*
* common.c
* written by Holmes Futrell
* use however you want
*/
#include "common.h"
#include "SDL.h"
#include <stdlib.h>
/*
Produces a random int x, min <= x <= max
following a uniform distribution
*/
int
randomInt(int min, int max)
{
return min + rand() % (max - min + 1);
}
/*
Produces a random float x, min <= x <= max
following a uniform distribution
*/
float
randomFloat(float min, float max)
{
return rand() / (float) RAND_MAX *(max - min) + min;
}
void
fatalError(const char *string)
{
printf("%s: %s\n", string, SDL_GetError());
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SDL_ShowSimpleMessageBox(SDL_MESSAGEBOX_ERROR, string, SDL_GetError(), NULL);
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static Uint64 prevTime = 0;
double
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updateDeltaTime(void)
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{
Uint64 curTime;
double deltaTime;
if (prevTime == 0) {
prevTime = SDL_GetPerformanceCounter();
}
curTime = SDL_GetPerformanceCounter();
deltaTime = (double) (curTime - prevTime) / (double) SDL_GetPerformanceFrequency();
prevTime = curTime;
return deltaTime;
}