Raytrack/interval.h at master · KipJM/Raytrack · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
//
// Created by mayua on 2025/08/24.
//

#ifndef RAYTRACINGWEEKEND_INTERVAL_H
#define RAYTRACINGWEEKEND_INTERVAL_H

#include "misc.h"

class interval
{
public:
	double min, max;

	interval() : min(+infinity), max(-infinity) {} // Default: empty interval
	interval(double min, double max) : min(min), max(max) {}

	/// returns an interval tightly encosing the two intervals
	interval(const interval& a, const interval& b)
	{
		min = a.min <= b.min ? a.min : b.min;
		max = a.max >= b.max ? a.max : b.max;
	}

	double size() const
	{
		return max - min;
	}

	bool contains(double x) const
	{
		return min <= x && x <= max;
	}

	bool surrounds(double x) const
	{
		return min < x && x < max;
	}


	double clamp(double x) const
	{
		if (x < min) return min;
		if (x > max) return max;
		return x;
	}

	interval expand(double delta) const
	{
		auto padding = delta/2;
		return {min - padding, max + padding};
	}

	static const interval empty, universe;

};

inline const interval interval::empty		= interval(+infinity, -infinity);
inline const interval interval::universe	= interval(-infinity, +infinity);

inline interval operator + (const interval& ival, double displacement)
{
	return {ival.min + displacement, ival.max + displacement};
}

inline interval operator + (double displacement, const interval& ival)
{
	return ival + displacement;
}

#endif //RAYTRACINGWEEKEND_INTERVAL_H