#pragma once
#include <time.h>
#include <math.h>
#include "typedef.h"

inline F64 t_nows() {
  struct timespec ts;
  clock_gettime( CLOCK_MONOTONIC, &ts );
  return (F64)ts.tv_sec + (F64)ts.tv_nsec * 1e-9;
}


inline F32 fade_alpha( F64 since, F64 now ) {
  if( since <= 0.0 )
    return 0.0f;
  F64 a = ( now - since - 0.30 ) / 0.30;
  if( a < 0.0 ) a = 0.0;
  if( a > 1.0 ) a = 1.0;
  return (F32)a;
}

inline F32 vec_dist( F32 x1, F32 y1, F32 z1, F32 x2, F32 y2, F32 z2 ) {
  F32 dx = x1 - x2;
  F32 dy = y1 - y2;
  F32 dz = z1 - z2;
  return sqrtf( dx * dx + dy * dy + dz * dz );
}