float sd_sphere(vec3 point, vec3 eulers, vec3 scale) { float radius = 1.; point.yz *= rm_rotation(eulers.x); point.xy *= rm_rotation(eulers.z); point.xz *= rm_rotation(-eulers.y); point /= scale; return (length(point) - radius) * min(scale.x, min(scale.y, scale.z)); } float ray_march_sd_sphere(vec3 ray_origin, vec3 ray_dir, int max_steps, float max_dist, float dist_threshold, vec3 sphere_pos, vec3 eulers, vec3 scale) { ray_dir = normalize(ray_dir); dist_threshold = abs(dist_threshold); float dist_from_origin = 0.; float dist_to_surface; for(int i = 0; i < max_steps; i++) { vec3 point = ray_origin + dist_from_origin * ray_dir; dist_to_surface = sd_sphere(point - sphere_pos, eulers, scale); dist_from_origin += dist_to_surface; if(dist_to_surface < dist_threshold || dist_to_surface > max_dist) break; } return dist_from_origin; }