/* @param background_color this is not ambient light */
void raytracing(uint8_t *pixels, color background_color,
rectangular_node rectangulars, sphere_node spheres,
light_node lights, const viewpoint *view,
int width, int height)
{
point3 u, v, w;
int height_divide[THREAD_NUM+1];
pthread_t id[THREAD_NUM];
Thread_parameter para;
Thread_range range[THREAD_NUM];
/* calculate u, v, w */
calculateBasisVectors(u, v, w, view);
int factor = sqrt(SAMPLES);
for(int i=0; i<=THREAD_NUM; i++) {
height_divide[i] = height * i / THREAD_NUM;
}
para.factor = factor;
para.u = u;
para.v = v;
para.w = w;
para.pixels = pixels;
para.background_color = background_color;
para.rectangulars = rectangulars;
para.spheres = spheres;
para.lights = lights;
para.view = view;
para.width = width;
para.height = height;
for(int i=0; i<THREAD_NUM; i++) {
range[i].height1 = height_divide[i];
range[i].height2 = height_divide[i+1];
range[i].ptr = ¶
}
for(int i=0; i<THREAD_NUM; i++) {
if(pthread_create(id+i, NULL, parallel, &range[i])) {
printf("Thread created fail.\n");
exit(1);
}
}
for(int i=0; i<THREAD_NUM; i++) {
pthread_join(id[i], NULL);
}
}
void raytracing(uint8_t *pixels, color background_color,
rectangular_node rectangulars, sphere_node spheres,
light_node lights, const viewpoint *view,
int width, int height)
{
point3 u, v, w, d;
color object_color = { 0.0, 0.0, 0.0 };
//PThread
int height_divide[THREAD_NUM];
pthread_t id[THREAD_NUM];
Threadsame same;
Threadinside inside[THREAD_NUM];
/* calculate u, v, w */
calculateBasisVectors(u, v, w, view);
int factor = sqrt(SAMPLES);
int i = 0;
for(i=0; i<=THREAD_NUM; i++) {
height_divide[i] = height * i / THREAD_NUM;
}
same.factor = factor;
same.u = u;
same.v = v;
same.w = w;
same.pixels = pixels;
same.background_color = background_color;
same.rectangulars = rectangulars;
same.spheres = spheres;
same.view = view;
same.width = width;
same.height = height;
for(i=0;i<THREAD_NUM;i++){
inside[i].h1 = height_divide[i];
inside[i].h2 = height_divide[i+1];
inside[i].p = &same;
}
for(i=0;i<THREAD_NUM;i++){
if(pthread_create(id+i,NULL,parallel,&inside[i])){
printf("Thread create fail.\n");
exit(1);
}
}
for(i=0;i<THREAD_NUM;i++){
pthread_join(id[i],NULL);
}
}
static unsigned int ray_color(const point3 e, double t,
const point3 d,
idx_stack *stk,
const rectangular_node rectangulars,
const sphere_node spheres,
const light_node lights,
color object_color, int bounces_left)
{
rectangular_node hit_rec = NULL, light_hit_rec = NULL;
sphere_node hit_sphere = NULL, light_hit_sphere = NULL;
double diffuse, specular;
point3 l, _l, r, rr;
object_fill fill;
color reflection_part;
color refraction_part;
/* might be a reflection ray, so check how many times we've bounced */
if (bounces_left == 0) {
SET_COLOR(object_color, 0.0, 0.0, 0.0);
return 0;
}
/* check for intersection with a sphere or a rectangular */
intersection ip= ray_hit_object(e, d, t, MAX_DISTANCE, rectangulars,
&hit_rec, spheres, &hit_sphere);
if (!hit_rec && !hit_sphere)
return 0;
/* pick the fill of the object that was hit */
fill = hit_rec ?
hit_rec->element.rectangular_fill :
hit_sphere->element.sphere_fill;
void *hit_obj = hit_rec ? (void *) hit_rec : (void *) hit_sphere;
/* assume it is a shadow */
SET_COLOR(object_color, 0.0, 0.0, 0.0);
for (light_node light = lights; light; light = light->next) {
/* calculate the intersection vector pointing at the light */
subtract_vector(ip.point, light->element.position, l);
multiply_vector(l, -1, _l);
normalize(_l);
/* check for intersection with an object. use ignore_me
* because we don't care about this normal
*/
ray_hit_object(ip.point, _l, MIN_DISTANCE, length(l),
rectangulars, &light_hit_rec,
spheres, &light_hit_sphere);
/* the light was not block by itself(lit object) */
if (light_hit_rec || light_hit_sphere)
continue;
compute_specular_diffuse(&diffuse, &specular, d, l,
ip.normal, fill.phong_power);
localColor(object_color, light->element.light_color,
diffuse, specular, &fill);
}
reflection(r, d, ip.normal);
double idx = idx_stack_top(stk).idx, idx_pass = fill.index_of_refraction;
if (idx_stack_top(stk).obj == hit_obj) {
idx_stack_pop(stk);
idx_pass = idx_stack_top(stk).idx;
} else {
idx_stack_element e = { .obj = hit_obj,
.idx = fill.index_of_refraction
};
idx_stack_push(stk, e);
}
refraction(rr, d, ip.normal, idx, idx_pass);
double R = (fill.T > 0.1) ?
fresnel(d, rr, ip.normal, idx, idx_pass) :
1.0;
/* totalColor = localColor +
mix((1-fill.Kd) * fill.R * reflection, T * refraction, R)
*/
if (fill.R > 0) {
/* if we hit something, add the color */
int old_top = stk->top;
if (ray_color(ip.point, MIN_DISTANCE, r, stk, rectangulars, spheres,
lights, reflection_part,
bounces_left - 1)) {
multiply_vector(reflection_part, R * (1.0 - fill.Kd) * fill.R,
reflection_part);
add_vector(object_color, reflection_part,
object_color);
}
stk->top = old_top;
}
/* calculate refraction ray */
if ((length(rr) > 0.0) && (fill.T > 0.0) &&
(fill.index_of_refraction > 0.0)) {
normalize(rr);
if (ray_color(ip.point, MIN_DISTANCE, rr, stk,rectangulars, spheres,
lights, refraction_part,
bounces_left - 1)) {
multiply_vector(refraction_part, (1 - R) * fill.T,
refraction_part);
add_vector(object_color, refraction_part,
object_color);
}
}
protect_color_overflow(object_color);
return 1;
}
/* @param background_color this is not ambient light */
void raytracing(void* args)
{
arg *data = (arg*) args;
point3 u, v, w, d;
color object_color = { 0.0, 0.0, 0.0 };
const viewpoint *view = (*data).View;
color back = { 0.0 , 0.1 , 0.1 };
uint8_t *pixels = data->pixels;
int start_j,end_j;
/* Separate to count the pixels */
if(pthread_equal(pthread_self(),THREAD[0])) {
start_j = 0;
end_j = 128;
} else if(pthread_equal(pthread_self(),THREAD[1])) {
start_j = 128;
end_j = 256;
} else if(pthread_equal(pthread_self(),THREAD[2])) {
start_j = 256;
end_j = 384;
} else if(pthread_equal(pthread_self(),THREAD[3])) {
start_j = 384;
end_j = 512;
}
/* calculate u, v, w */
calculateBasisVectors(u, v, w, view);
idx_stack stk;
int factor = sqrt(SAMPLES);
#pragma omp parallel for num_threads(64) \
private(stk), private(d), \
private(object_color)
for (int j = start_j ; j < end_j; j++) {
for (int i = 0 ; i < (*data).row; i++) {
double r = 0, g = 0, b = 0;
/* MSAA */
for (int s = 0; s < SAMPLES; s++) {
idx_stack_init(&stk);
rayConstruction(d, u, v, w,
i * factor + s / factor,
j * factor + s % factor,
view,
(*data).row * factor, (*data).col * factor);
if (ray_color(view->vrp, 0.0, d, &stk,(*data).rectangulars,
(*data).spheres, (*data).lights, object_color,
MAX_REFLECTION_BOUNCES)) {
r += object_color[0];
g += object_color[1];
b += object_color[2];
} else {
r += back[0];
g += back[1];
b += back[2];
}
pixels[((i + (j * (*data).row)) * 3) + 0] = r * 255 / SAMPLES;
pixels[((i + (j * (*data).row)) * 3) + 1] = g * 255 / SAMPLES;
pixels[((i + (j * (*data).row)) * 3) + 2] = b * 255 / SAMPLES;
}
}
}
}
