double gauss_diff(){
static pfi::math::random::random<mersenne_twister> r;
static double last_val = r.next_gaussian();
double cur_val = r.next_gaussian();
double ret = (last_val-cur_val)/sqrt(2.0);
last_val=cur_val;
return ret;
}
ratio<int> gen_ratio(){
static pfi::math::random::random<mersenne_twister> r;
int num=r.next_int(0,1000)-500;
int den=r.next_int(0,1000)-500;
if(den>=0)++den;
if(num>=0)++num;
return ratio<int>(num,den);
}
ppm<color> rand_ppm(image_coordinate_t w=Rand.next_int(50,200),
image_coordinate_t h=Rand.next_int(50,200),
rgb<color> bc=rgb<color>
(Rand.next_int(256),Rand.next_int(256),Rand.next_int(256))){
ppm<color> p(w,h,bc);
for(int y=0;y<p.height();++y){
for(int x=0;x<p.width();++x){
p(x,y)=rand_rgb<color>();
}
}
return p;
}
TEST(ppm,access_by_complex_and_vector){
for(int n=0;n<N;++n){
ppm<uint8_t> p=rand_ppm<uint8_t>();
for(int i=0;i<1000;++i){
double
x=Rand.next_double(-10,p.width()+10),
y=Rand.next_double(-10,p.height()+10);
complex<double> z(x,y);
vector2<double> pt(x,y);
EXPECT_TRUE(p(x,y)==p(z));
EXPECT_TRUE(p(x,y)==p(pt));
}
}
}
TEST(ppm,out_of_range_access_safety){
for(int n=0;n<N;++n){
ppm<uint8_t> p=rand_ppm<uint8_t>(), p_orig=p;
for(int t=0;t<100;++t){
int x,y;
*((uint32_t*)&x)=Rand.next_int();
*((uint32_t*)&y)=Rand.next_int();
EXPECT_TRUE(p(x,y)==p.bgcolor);
p(x,y)=rand_rgb<uint8_t>();
}
for(int y=0;y<p.height();++y){
for(int x=0;x<p.width();++x){
p(x,y)==p_orig(x,y);
}
}
}
}
rgb<color> rand_rgb(){
return rgb<color>((color)Rand.next_int(256),
(color)Rand.next_int(256),
(color)Rand.next_int(256));
}
double gauss_shifted(){
static pfi::math::random::random<mersenne_twister> r;
return (r.next_gaussian(42.0, 24.0)-42.0)/24.0;
}
double gauss(){
static pfi::math::random::random<mersenne_twister> r;
return r.next_gaussian();
}
double uniform(){
// unform distribution
static pfi::math::random::random<mersenne_twister> r;
return r.next_double(-sqrt(3.0),sqrt(3.0));
}
