WallyHackenslacker/PhotonMF
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Added indirect illumination.

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Wally Hackenslacker
2017-01-05 06:16:14 -04:00
parent 3f13372071
commit 96fe34975e
11 changed files with 268 additions and 59196 deletions
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128
tracer.cpp
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@@ -2,24 +2,19 @@
#include <limits>
#include <cstdlib>
#include <glm/gtc/constants.hpp>
#include "tracer.hpp"
#define MAX_RECURSION 9
#define MAX_RECURSION 3
#define BIAS 0.000001f
using namespace std;
using std::numeric_limits;
using glm::normalize;
using glm::radians;
using glm::dot;
using glm::reflect;
using glm::refract;
using glm::clamp;
using glm::tan;
using glm::sqrt;
using namespace glm;
static const vec3 BCKG_COLOR = vec3(0.16f, 0.66f, 0.72f);
static const vec3 BCKG_COLOR = vec3(0.0f);
static inline float random01() {
return static_cast<float>(rand()) / static_cast<float>(RAND_MAX);
@@ -56,14 +51,15 @@ vec2 Tracer::sample_pixel(int i, int j) const {
vec3 Tracer::trace_ray(Ray & r, vector<Figure *> & v_figures, vector<Light *> & v_lights, unsigned int rec_level) const {
float t, _t;
Figure * _f;
vec3 n, color, i_pos, ref;
vec3 n, color, i_pos, ref, sample, dir_diff_color, dir_spec_color, ind_color;
Ray mv_r, sr, rr;
bool vis;
float kr;
float kr, r1, r2;
t = numeric_limits<float>::max();
_f = NULL;
// Find the closest intersecting surface.
for (size_t f = 0; f < v_figures.size(); f++) {
if (v_figures[f]->intersect(r, _t) && _t < t) {
t = _t;
@@ -71,45 +67,99 @@ vec3 Tracer::trace_ray(Ray & r, vector<Figure *> & v_figures, vector<Light *> &
}
}
// If this ray intersects something:
if (_f != NULL) {
// Take the intersection point and the normal of the surface at that point.
i_pos = r.m_origin + (t * r.m_direction);
n = _f->normal_at_int(r, t);
for (size_t l = 0; l < v_lights.size(); l++) {
vis = true;
sr = Ray(v_lights[l]->direction(i_pos), i_pos + n * BIAS);
// Check if the material is not reflective/refractive.
if( !_f->m_mat.m_refract && _f->m_mat.m_rho == 0.0f) {
// Calculate the direct lighting.
for (size_t l = 0; l < v_lights.size(); l++) {
// For every light source
vis = true;
for (size_t f = 0; f < v_figures.size(); f++) {
if (v_figures[f]->intersect(sr, _t) && _t < v_lights[l]->distance(i_pos)) {
vis = false;
break;
// Cast a shadow ray to determine visibility.
sr = Ray(v_lights[l]->direction(i_pos), i_pos + n * BIAS);
for (size_t f = 0; f < v_figures.size(); f++) {
if (v_figures[f]->intersect(sr, _t) && _t < v_lights[l]->distance(i_pos)) {
vis = false;
break;
}
}
// Evaluate the shading model accounting for visibility.
dir_diff_color += (vis ? 1.0f : 0.0f) * v_lights[l]->diffuse(n, r, t, _f->m_mat);
dir_spec_color += (vis ? 1.0f : 0.0f) * v_lights[l]->specular(n, r, t, _f->m_mat);
}
color += (vis ? 1.0f : 0.0f) * v_lights[l]->shade(n, r, t, _f->m_mat);
// If enabled, calculate indirect lighting contribution.
if (indirect_l && rec_level < MAX_RECURSION) {
r1 = random01();
r2 = random01();
sample = sample_hemisphere(r1, r2);
rotate_sample(sample, n);
rr = Ray(normalize(sample), i_pos + (sample * BIAS));
ind_color += r1 * trace_ray(rr, v_figures, v_lights, rec_level + 1) / (1.0f / (2.0f * pi<float>()));
}
color += ((dir_diff_color + ind_color) * (_f->m_mat.m_diffuse / pi<float>())) + dir_spec_color;
} else {
// If the material has reflection/transmission enabled.
// Calculate the Fresnel term if the surface is refracting.
if (_f->m_mat.m_refract)
kr = fresnel(r.m_direction, n, r.m_ref_index, _f->m_mat.m_ref_index);
else
kr = _f->m_mat.m_rho;
// Determinte the specular reflection color.
if (kr > 0.0f && rec_level < MAX_RECURSION) {
rr = Ray(normalize(reflect(r.m_direction, n)), i_pos + n * BIAS);
color += _f->m_mat.m_rho * kr * trace_ray(rr, v_figures, v_lights, rec_level + 1);
} else if (rec_level >= MAX_RECURSION)
return vec3(0.0f);
// Determine the transmission color.
if (_f->m_mat.m_refract && kr < 1.0f && rec_level < MAX_RECURSION) {
rr = Ray(normalize(refract(r.m_direction, n, r.m_ref_index / _f->m_mat.m_ref_index)), i_pos - n * BIAS, _f->m_mat.m_ref_index);
color += (1.0f - _f->m_mat.m_rho) * (1.0f - kr) * trace_ray(rr, v_figures, v_lights, rec_level + 1);
} else if (rec_level >= MAX_RECURSION)
return vec3(0.0f);
}
if (_f->m_mat.m_refract)
kr = fresnel(r.m_direction, n, r.m_ref_index, _f->m_mat.m_ref_index);
else
kr = _f->m_mat.m_rho;
if (kr > 0.0f && rec_level < MAX_RECURSION) {
rr = Ray(normalize(reflect(r.m_direction, n)), i_pos + n * BIAS);
color += _f->m_mat.m_rho * kr * trace_ray(rr, v_figures, v_lights, rec_level + 1);
} else if (rec_level >= MAX_RECURSION)
return vec3(BCKG_COLOR);
if (_f->m_mat.m_refract && kr < 1.0f && rec_level < MAX_RECURSION) {
rr = Ray(normalize(refract(r.m_direction, n, r.m_ref_index / _f->m_mat.m_ref_index)), i_pos - n * BIAS, _f->m_mat.m_ref_index);
color += (1.0f - _f->m_mat.m_rho) * (1.0f - kr) * trace_ray(rr, v_figures, v_lights, rec_level + 1);
} else if (rec_level >= MAX_RECURSION)
return vec3(BCKG_COLOR);
// Return final color.
return clamp(color, 0.0f, 1.0f);
} else
return vec3(BCKG_COLOR);
}
/* Helper functions pretty much taken from scratchapixel.com */
void Tracer::create_coords_system(const vec3 &n, vec3 &nt, vec3 &nb) const {
if (abs(n.x) > abs(n.y))
nt = normalize(vec3(n.z, 0.0f, -n.x));
else
nt = normalize(vec3(0.0f, -n.z, n.y));
nb = normalize(cross(n, nt));
}
vec3 Tracer::sample_hemisphere(const float r1, const float r2) const {
float sin_t = sqrt(1.0f - (r1 * r1));
float phi = 2 * pi<float>() * r2;
float x = sin_t * cos(phi);
float z = sin_t * sin(phi);
return vec3(x, r1, z);
}
void Tracer::rotate_sample(vec3 & sample, const vec3 & n) const {
vec3 nt, nb;
mat3 rot_m;
create_coords_system(n, nt, nb);
sample = vec3(sample.x * nb.x + sample.y * n.x + sample.z * nt.x,
sample.x * nb.y + sample.y * n.y + sample.z * nt.y,
sample.x * nb.z + sample.y * n.z + sample.z * nt.z);
}