58 lines
1.5 KiB
C++
58 lines
1.5 KiB
C++
#ifndef INTERVAL_H
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#define INTERVAL_H
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#include "rayTracer.h"
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class interval {
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public:
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double min, max;
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// Fegault interval is empty.
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interval() : min(+infinity), max(-infinity) {}
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interval(double min, double max) : min(min), max(max) {}
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interval(const interval& a, const interval& b) {
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// Create the interval tightly enclosing the two input intervals.
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min = a.min <= b.min ? a.min : b.min;
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max = a.max >= b.max ? a.max : b.max;
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}
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double size() const {
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return max - min;
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}
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bool contains(double x) const {
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return min <= x && x <= max;
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}
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bool surrounds(double x) const {
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return min < x && x < max;
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}
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double clamp(double x) const {
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if (x < min) return min;
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if (x > max) return max;
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return x;
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}
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interval expand(double delta) const {
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auto padding = delta / 2;
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return interval(min - padding, max + padding);
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}
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static const interval empty, universe;
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};
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const interval interval::empty = interval(+infinity, -infinity);
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const interval interval::universe = interval(-infinity, +infinity);
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interval operator+(const interval& ival, double displacement) {
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return interval(ival.min + displacement, ival.max + displacement);
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}
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interval operator+(double displacement, const interval& ival) {
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return ival + displacement;
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}
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#endif |