Render surface normals

This commit is contained in:
Jean-Michel Gorius 2022-11-10 22:12:35 +01:00
parent e1173e5bd3
commit 647abd385d

17
main.c
View File

@ -1,3 +1,4 @@
#include <math.h>
#include <stdbool.h> #include <stdbool.h>
#include <stdio.h> #include <stdio.h>
@ -6,20 +7,26 @@
#include "ray.h" #include "ray.h"
#include "vec3.h" #include "vec3.h"
bool hit_sphere(point3 center, double radius, ray r) { double hit_sphere(point3 center, double radius, ray r) {
vec3 oc = point3_sub(r.origin, center); vec3 oc = point3_sub(r.origin, center);
double a = vec3_length2(r.direction); double a = vec3_length2(r.direction);
double b = 2 * vec3_dot(oc, r.direction); double b = 2 * vec3_dot(oc, r.direction);
double c = vec3_length2(oc) - radius * radius; double c = vec3_length2(oc) - radius * radius;
double discriminant = b * b - 4 * a * c; double discriminant = b * b - 4 * a * c;
return discriminant > 0; if (discriminant < 0)
return -1.0;
else
return (-b - sqrt(discriminant)) / (2.0 * a);
} }
color ray_color(ray r) { color ray_color(ray r) {
if (hit_sphere((point3){0, 0, -1}, 0.5, r)) double t = hit_sphere((point3){0, 0, -1}, 0.5, r);
return (color){1, 0, 0}; if (t > 0.0) {
vec3 n = vec3_normalize(point3_sub(ray_at(r, t), (point3){0, 0, -1}));
return (color){0.5 * (n.x + 1), 0.5 * (n.y + 1), 0.5 * (n.z + 1)};
}
vec3 unit_direction = vec3_normalize(r.direction); vec3 unit_direction = vec3_normalize(r.direction);
double t = 0.5 * (unit_direction.y + 1.0); t = 0.5 * (unit_direction.y + 1.0);
color gradient1 = {1.0, 1.0, 1.0}; color gradient1 = {1.0, 1.0, 1.0};
color gradient2 = {0.5, 0.7, 1.0}; color gradient2 = {0.5, 0.7, 1.0};
return color_lerp(gradient1, gradient2, t); return color_lerp(gradient1, gradient2, t);