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