24 lines
681 B
C++
24 lines
681 B
C++
#include "tracer.hpp"
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using glm::dot;
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using glm::normalize;
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using glm::refract;
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const float BIAS = 0.000001f;
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const vec3 BCKG_COLOR = vec3(1.0f);
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float Tracer::fresnel(const vec3 & i, const vec3 & n, const float ir1, const float ir2) const {
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float cos_t1 = dot(i, n);
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float cos_t2 = dot(normalize(refract(i, n, ir1 / ir2)), n);
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float sin_t2 = (ir1 / ir2) * glm::sqrt(1.0f - (cos_t2 * cos_t2));
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if (sin_t2 >= 1.0f)
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return 1.0f;
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float fr_par = ((ir2 * cos_t1) - (ir1 * cos_t2)) / ((ir2 * cos_t1) + (ir1 * cos_t2));
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float fr_per = ((ir1 * cos_t2) - (ir2 * cos_t1)) / ((ir1 * cos_t2) + (ir2 * cos_t1));
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return ((fr_par * fr_par) + (fr_per * fr_per)) / 2.0f;
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}
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