63 lines
1.7 KiB
C++
63 lines
1.7 KiB
C++
#include "Sphere.h"
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#include "InfiniteRay.h"
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#include "PackStream.h"
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#include <cmath>
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Sphere::Sphere(const Vector3 ¢er, double radius) : center(center), radius(radius) {
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radius2 = radius * radius;
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}
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int Sphere::checkRayIntersection(const InfiniteRay &ray) const {
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Vector3 L = ray.getOrigin().sub(center);
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double b = 2.0 * ray.getDirection().dotProduct(L);
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double c = L.dotProduct(L) - radius2;
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double discr = b * b - 4.0 * c;
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if (discr < 0) {
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return 0;
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} else if (discr == 0) {
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return 1;
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} else {
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return 2;
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}
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}
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int Sphere::findRayIntersection(const InfiniteRay &ray, Vector3 *first_intersection,
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Vector3 *second_intersection) const {
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Vector3 L = ray.getOrigin().sub(center);
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double b = 2.0 * ray.getDirection().dotProduct(L);
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double c = L.dotProduct(L) - radius2;
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double discr = b * b - 4.0 * c;
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if (discr < 0) {
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return 0;
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} else if (discr == 0) {
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*first_intersection = ray.getPointAtCursor(-0.5 * b);
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return 1;
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} else {
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double x0 = (b > 0.0) ? -0.5 * (b + sqrt(discr)) : -0.5 * (b - sqrt(discr));
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double x1 = c / x0;
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if (x0 > x1) {
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*first_intersection = ray.getPointAtCursor(x1);
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*second_intersection = ray.getPointAtCursor(x0);
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} else {
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*first_intersection = ray.getPointAtCursor(x0);
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*second_intersection = ray.getPointAtCursor(x1);
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}
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return 2;
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}
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}
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void Sphere::save(PackStream *stream) const {
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center.save(stream);
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stream->write(&radius);
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stream->write(&radius2);
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}
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void Sphere::load(PackStream *stream) {
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center.load(stream);
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stream->read(&radius);
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stream->read(&radius2);
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}
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