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Use tabs instead of spaces, remove unused code, drop metallic materials

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cozis
2024-09-30 21:53:06 +02:00
parent 1aafa05988
commit 0ae5e22ad2
1 changed files with 259 additions and 175 deletions
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src/main.c
+205 -121
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@@ -15,14 +15,19 @@
#include "sync.h" #include "sync.h"
#include "mesh.h" #include "mesh.h"
typedef struct { typedef struct {
Vector3 albedo; Vector3 albedo;
float metallic;
float roughness; float roughness;
float reflectance;
float emission_power; float emission_power;
Vector3 emission_color; Vector3 emission_color;
} Material; } Material;
#ifndef M_PI
#define M_PI 3.1415926538
#endif
int screen_w; int screen_w;
int screen_h; int screen_h;
@@ -321,27 +326,8 @@ bool intersect_object(Ray r, Object o, float *t, Vector3 *normal)
return false; return false;
} }
unsigned int wang_hash(unsigned int seed)
{
seed = (seed ^ 61) ^ (seed >> 16);
seed *= 9;
seed = seed ^ (seed >> 4);
seed *= 0x27d4eb2d;
seed = seed ^ (seed >> 15);
return seed;
}
unsigned int pcg_hash(unsigned int input)
{
unsigned int state = input * 747796405U + 2891336453U;
unsigned int word = ((state >> ((state >> 28U) + 4U)) ^ state) * 277803737U;
return (word >> 22U) ^ word;
}
float random_float(void) float random_float(void)
{ {
// *seed = pcg_hash(*seed);
// return (float) *seed / UINT_MAX;
return (float) rand() / RAND_MAX; return (float) rand() / RAND_MAX;
} }
@@ -418,105 +404,108 @@ HitInfo trace_ray(Ray ray)
} }
} }
float clamp(float x, float min, float max)
{
assert(min <= max);
if (x < min) return min;
if (x > max) return max;
return x;
}
Vector3 maxv(Vector3 a, Vector3 b)
{
return (Vector3) {
max(a.x, b.x),
max(a.y, b.y),
max(a.z, b.z),
};
}
Vector3 vec_from_scalar(float s)
{
return (Vector3) {s, s, s};
}
Vector3 fresnelSchlickRoughness(float cosTheta, Vector3 F0, float roughness)
{
return combine(F0, combine(maxv(vec_from_scalar(1.0 - roughness), F0), F0, 1, -1), 1, pow(clamp(1.0 - cosTheta, 0.0, 1.0), 5.0));
}
float geometrySmith(float NoV, float NoL, float a) {
float a2 = a * a;
float GGXL = NoV * sqrt((-NoL * a2 + NoL) * NoL + a2);
float GGXV = NoL * sqrt((-NoV * a2 + NoV) * NoV + a2);
return 0.5 / (GGXV + GGXL);
}
float distribGGX(float NoH, float roughness) {
float a = NoH * roughness;
float k = roughness / (1.0 - NoH * NoH + a * a);
return k * k * (1.0 / M_PI);
}
Vector3 pixel(float x, float y) Vector3 pixel(float x, float y)
{ {
Ray original_ray = ray_through_screen_at(x, y, (float) screen_w/screen_h); Ray in_ray = ray_through_screen_at(x, y, (float) screen_w/screen_h);
Vector3 sky_color = {0.6, 0.7, 0.9}; Vector3 sky_color = {0.6, 0.7, 0.9};
//Vector3 sky_color = {0, 0, 0}; //Vector3 sky_color = {0, 0, 0};
//Vector3 sky_color = {1, 1, 1};
int diffuse_rays = 1; Vector3 contrib = {1, 1, 1};
int specular_rays = 1; Vector3 result = {0, 0, 0};
for (int i = 0; i < 1000; i++) {
Vector3 diffuse_contrib = {1, 1, 1}; HitInfo hit = trace_ray(in_ray);
Vector3 diffuse_light = {0, 0, 0};
Ray ray = original_ray;
for (int j = 0; j < diffuse_rays; j++) {
int bounces = 4;
for (int i = 0; i < bounces; i++) {
HitInfo hit = trace_ray(ray);
if (hit.object == -1) { if (hit.object == -1) {
diffuse_light = combine(diffuse_light, mulv(sky_color, diffuse_contrib), 1, 1); result = combine(result, mulv(sky_color, contrib), 1, 1);
break; break;
} }
Material material = objects[hit.object].material; Material material = objects[hit.object].material;
diffuse_contrib = mulv(diffuse_contrib, material.albedo);
diffuse_light = combine(diffuse_light, material.emission_color, 1, material.emission_power);
float base_specular = 0.04; // Dielectrics Vector3 reflect_dir = reflect(in_ray.direction, scale(hit.normal, -1));
float specular_ratio = base_specular * (1 - material.metallic) + material.metallic; Vector3 rand_dir = random_direction();
float diffuse_ratio = 1 - specular_ratio; if (dotv(rand_dir, hit.normal) < 0)
rand_dir = scale(rand_dir, -1);
Vector3 out_dir = normalize(combine(rand_dir, reflect_dir, material.roughness, 1));
Ray out_ray = (Ray) { combine(hit.point, out_dir, 1, 0.001), out_dir };
Vector3 diffuse_dir;
{ {
diffuse_dir = random_direction(); float perceptualRoughness = max(material.roughness, 0.089);
if (dotv(diffuse_dir, hit.normal) < 0) float roughness = perceptualRoughness * perceptualRoughness;
diffuse_dir = scale(diffuse_dir, -1);
Vector3 v = scale(in_ray.direction, -1);
Vector3 l = out_dir;
Vector3 n = hit.normal;
Vector3 h = normalize(combine(v, l, 1, 1));
float NoH = dotv(n, v);
float LoH = dotv(l, h);
float NoV = dotv(n, v);
float NoL = dotv(n, l);
Vector3 f0 = vec_from_scalar(0.16 * material.reflectance * material.reflectance);
float D = distribGGX(NoH, roughness);
Vector3 F = fresnelSchlickRoughness(LoH, f0, roughness);
float V = geometrySmith(NoV, NoL, roughness);
Vector3 specular = scale(F, (D * V) / (4.0 * NoV * NoL + 0.0001));
Vector3 diffuse = mulv(combine((Vector3) {1, 1, 1}, F, 1, -1), material.albedo);
result = combine(result, mulv(contrib, material.emission_color), 1, material.emission_power);
contrib = mulv(contrib, scale(combine(diffuse, specular, 1, 1), NoL));
} }
Vector3 specular_dir; in_ray = out_ray;
{
Vector3 reflect_dir = reflect(ray.direction, scale(hit.normal, -1));
Vector3 noise_dir = scale(random_direction(), material.roughness);
if (dotv(noise_dir, reflect_dir) < 0)
noise_dir = scale(noise_dir, -1);
specular_dir = combine(noise_dir, reflect_dir, 1, 1);
} }
Vector3 new_dir = combine(diffuse_dir, specular_dir, diffuse_ratio, specular_ratio); result.x = clamp(result.x, 0, 1);
result.y = clamp(result.y, 0, 1);
result.z = clamp(result.z, 0, 1);
ray = (Ray) { combine(hit.point, new_dir, 1, 0.001), new_dir }; return result;
}
}
diffuse_light = scale(diffuse_light, 1.0f / diffuse_rays);
/*
Vector3 specular_contrib = {1, 1, 1};
Vector3 specular_light = {0, 0, 0};
ray = original_ray;
for (int j = 0; j < specular_rays; j++) {
int bounces = 4;
for (int i = 0; i < bounces; i++) {
HitInfo hit = trace_ray(ray);
if (hit.object == -1) {
Vector3 sky_color = {0.6, 0.7, 0.9};
//Vector3 sky_color = {0, 0, 0};
specular_light = combine(specular_light, mulv(sky_color, specular_contrib), 1, 1);
break;
}
Material material = objects[hit.object].material;
specular_contrib = mulv(specular_contrib, material.albedo);
specular_light = combine(specular_light, material.emission_color, 1, material.emission_power);
Vector3 reflect_dir = reflect(ray.direction, scale(hit.normal, -1));
float roughness = objects[hit.object].material.roughness;
Vector3 noise_dir = scale(random_direction(), roughness);
if (dotv(noise_dir, reflect_dir) < 0)
noise_dir = scale(noise_dir, -1);
Vector3 new_dir = combine(noise_dir, reflect_dir, roughness, 1 - roughness);
ray = (Ray) { combine(hit.point, new_dir, 1, 0.001), new_dir };
}
}
specular_light = scale(specular_light, 1.0f / specular_rays);
float base_specular = 0.04; // Dielectrics
float specilar_ratio = base_specular * ()
light = scale(light, 1.0f/(specular_rays + diffuse_rays));
*/
Vector3 light = diffuse_light;
return light;
} }
uint32_t accum_generation = 0; uint32_t accum_generation = 0;
@@ -525,14 +514,14 @@ Vector3 *frame = NULL;
int frame_w = 0; int frame_w = 0;
int frame_h = 0; int frame_h = 0;
unsigned int frame_texture; unsigned int frame_texture;
uint64_t accum_index = 1; uint64_t accum_count = 0;
os_mutex_t frame_mutex; os_mutex_t frame_mutex;
os_threadreturn worker(void*) os_threadreturn worker(void*)
{ {
uint32_t local_accum_generation = 0; uint32_t local_accum_generation = 0;
Vector3 *local_accum = NULL; Vector3 *local_accum = NULL;
uint64_t local_accum_index = 1; uint64_t local_accum_count = 0;
int local_frame_w = 0; int local_frame_w = 0;
int local_frame_h = 0; int local_frame_h = 0;
@@ -544,7 +533,7 @@ os_threadreturn worker(void*)
if (accum != NULL && local_accum != NULL && local_accum_generation == accum_generation) { if (accum != NULL && local_accum != NULL && local_accum_generation == accum_generation) {
for (int i = 0; i < frame_w * frame_h; i++) for (int i = 0; i < frame_w * frame_h; i++)
accum[i] = combine(accum[i], local_accum[i], 1, 1); accum[i] = combine(accum[i], local_accum[i], 1, 1);
accum_index += local_accum_index; accum_count += local_accum_count;
} }
memset(local_accum, 0, sizeof(Vector3) * local_frame_w * local_frame_h); memset(local_accum, 0, sizeof(Vector3) * local_frame_w * local_frame_h);
if (local_frame_w != frame_w || local_frame_h != frame_h) if (local_frame_w != frame_w || local_frame_h != frame_h)
@@ -552,7 +541,7 @@ os_threadreturn worker(void*)
local_accum_generation = accum_generation; local_accum_generation = accum_generation;
local_frame_w = frame_w; local_frame_w = frame_w;
local_frame_h = frame_h; local_frame_h = frame_h;
local_accum_index = 1; local_accum_count = 0;
os_mutex_unlock(&frame_mutex); os_mutex_unlock(&frame_mutex);
if (resize) { if (resize) {
@@ -585,7 +574,7 @@ os_threadreturn worker(void*)
local_accum[pixel_index] = combine(local_accum[pixel_index], color, 1, 1); local_accum[pixel_index] = combine(local_accum[pixel_index], color, 1, 1);
} }
local_accum_index++; local_accum_count++;
} }
} }
} }
@@ -594,7 +583,7 @@ os_threadreturn worker(void*)
void invalidate_accumulation(void) void invalidate_accumulation(void)
{ {
os_mutex_lock(&frame_mutex); os_mutex_lock(&frame_mutex);
accum_index = 1; accum_count = 0;
accum_generation++; accum_generation++;
os_mutex_unlock(&frame_mutex); os_mutex_unlock(&frame_mutex);
} }
@@ -616,12 +605,10 @@ void update_frame_texture(float s)
accum = malloc(sizeof(Vector3) * frame_w * frame_h); accum = malloc(sizeof(Vector3) * frame_w * frame_h);
if (!accum) { printf("OUT OF MEMORY\n"); abort(); } if (!accum) { printf("OUT OF MEMORY\n"); abort(); }
accum_index = 1; accum_count = 0;
} }
if (accum_index == 1) { if (accum_count == 0) {
//memset(accum, 0, sizeof(Vector3) * frame_w * frame_h);
for (int j = 0; j < frame_h; j++) for (int j = 0; j < frame_h; j++)
for (int i = 0; i < frame_w; i++) { for (int i = 0; i < frame_w; i++) {
@@ -632,6 +619,8 @@ void update_frame_texture(float s)
int pixel_index = j * frame_w + i; int pixel_index = j * frame_w + i;
accum[pixel_index] = pixel(u, v); accum[pixel_index] = pixel(u, v);
} }
accum_count++;
} }
for (int j = 0; j < frame_h; j++) for (int j = 0; j < frame_h; j++)
@@ -643,7 +632,7 @@ void update_frame_texture(float s)
v = 1 - v; v = 1 - v;
int pixel_index = j * frame_w + i; int pixel_index = j * frame_w + i;
frame[pixel_index] = scale(accum[pixel_index], 1.0f / accum_index); frame[pixel_index] = scale(accum[pixel_index], 1.0f / accum_count);
} }
glBindTexture(GL_TEXTURE_2D, frame_texture); glBindTexture(GL_TEXTURE_2D, frame_texture);
@@ -655,14 +644,105 @@ void update_frame_texture(float s)
int main(void) int main(void)
{ {
add_object(cube((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .roughness=1, .albedo=(Vector3) {1, 0, 0}}, (Vector3) {0, 0, 0}, (Vector3) {10, 5, 0.1})); #if 0
add_object(cube((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .roughness=1, .albedo=(Vector3) {1, 0, 0}}, (Vector3) {0, 0, 0}, (Vector3) {0.1, 5, 10})); float box_d = 3;
add_object(cube((Material) {.emission_color={0}, .emission_power=0, .metallic=1, .roughness=0, .albedo=(Vector3) {0.4, 0.3, 0.9}}, (Vector3) {0, -0.1, 0}, (Vector3) {10, 0.1, 10})); float box_w = 3;
float box_h = 5;
float box_border = 0.1;
add_object(cube((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .roughness=1, .albedo=(Vector3) {1, 0, 0}}, (Vector3) {7, 0, 8}, (Vector3) {1, 1, 1})); add_object(cube(
add_object(cube((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .roughness=1, .albedo=(Vector3) {1, 0, 1}}, (Vector3) {6, 0, 7}, (Vector3) {1, 1, 1})); (Material) {
add_object(sphere((Material) {.emission_color={1, 0.4, 0}, .emission_power=3, .metallic=0, .roughness=0, .albedo=(Vector3) {1, 0.4, 0}}, (Vector3) {3, 1, 3}, 1)); .emission_color={0},
add_object(sphere((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .roughness=0, .albedo=(Vector3) {0, 1, 0}}, (Vector3) {5, 1, 3}, 1)); .emission_power=0,
.roughness=1,
.metallic=0,
.albedo=(Vector3) {1, 1, 1}
},
(Vector3) {0, 0, 0},
(Vector3) {box_w, box_border, box_d}
));
add_object(cube(
(Material) {
.emission_color={0},
.emission_power=0,
.metallic=0,
.roughness=1,
.albedo=(Vector3) {1, 1, 1}
},
(Vector3) {0, box_h, 0},
(Vector3) {box_w, box_border, box_d}
));
add_object(cube(
(Material) {
.emission_color={0},
.emission_power=0,
.metallic=0,
.roughness=0,
.albedo=(Vector3) {1, 1, 1}
},
(Vector3) {0, 0, 0},
(Vector3) {box_border, box_h, box_d}
));
add_object(cube(
(Material) {
.emission_color={0},
.emission_power=0,
.metallic=0,
.roughness=0,
.albedo=(Vector3) {1, 1, 1}
},
(Vector3) {box_w, 0, 0},
(Vector3) {box_border, box_h, box_d}
));
add_object(cube(
(Material) {
.emission_color={0},
.emission_power=0,
.metallic=0,
.roughness=1,
.albedo=(Vector3) {1, 1, 1}
},
(Vector3) {0, 0, 0},
(Vector3) {box_w, box_h, box_border}
));
add_object(cube(
(Material) {
.emission_color={1, 1, 1},
.emission_power=10,
.metallic=0,
.roughness=1,
.albedo=(Vector3) {1, 1, 1}
},
(Vector3) {box_w/3, box_h-box_border, box_d/3},
(Vector3) {box_w/3, box_border, box_d/3}
));
add_object(sphere(
(Material) {
.emission_color={0},
.emission_power=0,
.metallic=0,
.roughness=0,
.albedo=(Vector3) {0, 1, 0}
},
(Vector3) {box_w/2, box_w/3, box_d/2},
box_w/3
));
#elif 1
add_object(cube ((Material) {.emission_color={0}, .emission_power=0, .reflectance=1, .roughness=1, .albedo=(Vector3) {1, 0.3, 0.3}}, (Vector3) {0, 0, 0}, (Vector3) {10, 5, 0.1}));
add_object(cube ((Material) {.emission_color={0}, .emission_power=0, .reflectance=1, .roughness=0.5, .albedo=(Vector3) {0.3, 1, 0.3}}, (Vector3) {0, 0, 0}, (Vector3) {0.1, 5, 10}));
add_object(cube ((Material) {.emission_color={0}, .emission_power=0, .reflectance=1, .roughness=0, .albedo=(Vector3) {0.4, 0.3, 0.9}}, (Vector3) {0, -0.1, 0}, (Vector3) {10, 0.1, 10}));
add_object(cube ((Material) {.emission_color={0}, .emission_power=0, .reflectance=1, .roughness=1, .albedo=(Vector3) {1, 0, 0}}, (Vector3) {7, 0, 8}, (Vector3) {1, 1, 1}));
add_object(cube ((Material) {.emission_color={0}, .emission_power=0, .reflectance=1, .roughness=1, .albedo=(Vector3) {1, 0, 1}}, (Vector3) {6, 0, 7}, (Vector3) {1, 1, 1}));
add_object(sphere((Material) {.emission_color={1, 0.4, 0.2}, .emission_power=3, .reflectance=1, .roughness=1, .albedo=(Vector3) {1, 0.4, 0}}, (Vector3) {3, 1, 3}, 1));
add_object(sphere((Material) {.emission_color={0}, .emission_power=0, .reflectance=1, .roughness=0, .albedo=(Vector3) {0, 1, 0}}, (Vector3) {5, 1, 3}, 1));
#endif
os_mutex_create(&frame_mutex); os_mutex_create(&frame_mutex);
@@ -683,7 +763,9 @@ int main(void)
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3); glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE); glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
GLFWwindow *window = glfwCreateWindow(640, 480, "Path Trace", NULL, NULL); int window_w = 2 * 640;
int window_h = 2 * 480;
GLFWwindow *window = glfwCreateWindow(window_w, window_h, "Path Trace", NULL, NULL);
if (!window) { if (!window) {
glfwTerminate(); glfwTerminate();
return -1; return -1;
@@ -741,8 +823,10 @@ int main(void)
glBindTexture(GL_TEXTURE_2D, frame_texture); glBindTexture(GL_TEXTURE_2D, frame_texture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); //glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); //glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
while (!glfwWindowShouldClose(window)) { while (!glfwWindowShouldClose(window)) {
@@ -756,7 +840,7 @@ int main(void)
Vector3 clear_color = {1, 1, 1}; Vector3 clear_color = {1, 1, 1};
update_frame_texture(0.4); update_frame_texture(0.6);
glViewport(0, 0, screen_w, screen_h); glViewport(0, 0, screen_w, screen_h);
glClearColor(clear_color.x, clear_color.y, clear_color.z, 1.0f); glClearColor(clear_color.x, clear_color.y, clear_color.z, 1.0f);