rsrt_cpu/src/render.rs

211 lines
8.2 KiB
Rust

extern crate mat4;
extern crate vec3;
extern crate vec4;
use crate::object::Object;
use crate::ray::Ray;
use crate::sphere::Sphere;
use sdl2::pixels::Color;
fn put_pixel(data: &mut [u8], x: usize, y: usize, color: Color) {
data[y * 3 * 800 + x * 3] = color.r;
data[y * 3 * 800 + x * 3 + 1] = color.g;
data[y * 3 * 800 + x * 3 + 2] = color.b;
}
pub fn render(data: &mut [u8], i: i32) {
let sphere = Sphere {};
let forward = *vec3::transform_mat4(
&mut vec3::new_zero(),
&vec3::new(0. as f64, 0. as f64, -1. as f64),
mat4::rotate(
&mut mat4::new_zero(),
&mat4::new_identity(),
&0.,
&(3.141592 / 4.),
&0.,
),
);
let view_matrix = *mat4::inv(
&mut mat4::new_zero(),
mat4::look_at(
&mut mat4::new_zero(),
&[100., 0., 100.],
&[100. + forward[0], 0. + forward[1], 100. + forward[2]],
&[0., 1., 0.],
),
);
// let view_matrix = *mat4::look_at(
// &mut mat4::new_zero(),
// &[0., 0., 10.],
// &[0., 0., 9.],
// &[0., 1., 0.],
// );
let scale = *mat4::scale(
&mut mat4::new_zero(),
&mat4::new_identity(),
&vec3::new(1. / 3., 1. / 3., 1. / 3.),
);
let translate = *mat4::translate(
&mut mat4::new_zero(),
&mat4::new_identity(),
&vec3::new(-i as f64, -i as f64, 0.),
);
let rotate = *mat4::transpose(
&mut mat4::new_zero(),
mat4::rotate(&mut mat4::new_zero(), &mat4::new_identity(), &0., &0., &0.),
);
let model_matrix_tmp = *mat4::mul(&mut mat4::new_zero(), &scale, &rotate);
let model_matrix1 = *mat4::mul(&mut mat4::new_zero(), &model_matrix_tmp, &translate);
let mut origin = [0., 0., 0.];
let test = origin;
vec3::transform_mat4(&mut origin, &test, &view_matrix);
let test = origin;
vec3::transform_mat4(&mut origin, &test, &model_matrix1);
let mut prelight = [-10., 10., 0.];
let test = prelight;
vec3::transform_mat4(&mut prelight, &test, &model_matrix1);
for x in 0..800 {
for y in 0..800 {
let pi_4: f64 = 3.141592 / 8.;
let dirx = (2. * ((x as f64 + 0.5) / 800.) - 1.) * pi_4.tan();
let diry = (1. - 2. * ((y as f64 + 0.5) / 800.)) * pi_4.tan();
let scalar = (dirx.powi(2) + diry.powi(2) + 1.).sqrt();
let mut ray = Ray {
origin: origin,
direction: [dirx / scalar, diry / scalar, -1. / scalar],
};
let test = ray.direction;
vec3::transform_mat4(&mut ray.direction, &test, &view_matrix);
let test = ray.direction;
vec3::transform_mat4(&mut ray.direction, &test, &model_matrix1);
ray.direction[0] = ray.direction[0] - ray.origin[0];
ray.direction[1] = ray.direction[1] - ray.origin[1];
ray.direction[2] = ray.direction[2] - ray.origin[2];
let scalar =
(ray.direction[0].powi(2) + ray.direction[1].powi(2) + ray.direction[2].powi(2))
.sqrt();
ray.direction = [
ray.direction[0] / scalar,
ray.direction[1] / scalar,
ray.direction[2] / scalar,
];
if x == 0 && y == 0 {
println!("{:?}", ray);
}
let ray2 = ray;
let mut distances = Vec::new();
distances.push(sphere.get_intersection(ray));
distances.push(None);
let a = (distances[0], distances[1]);
match a {
(Some(dist), None) => {
let n = [
ray.origin[0] + ray.direction[0] * dist,
ray.origin[1] + ray.direction[1] * dist,
ray.origin[2] + ray.direction[2] * dist,
];
let normal = sphere.get_normal(n);
let light = [prelight[0] - n[0], prelight[1] - n[1], prelight[2] - n[2]];
let scalar = (light[0].powi(2) + light[1].powi(2) + light[2].powi(2)).sqrt();
let light_d = [light[0] / scalar, light[1] / scalar, light[2] / scalar];
let mut diffuse =
normal[0] * light_d[0] + normal[1] * light_d[1] + normal[2] * light_d[2];
if diffuse < 0. {
diffuse = 0.;
}
put_pixel(
&mut *data,
x,
y,
Color {
r: (diffuse * 128. * 0.9 + 0.1 * 255.) as u8,
g: 0,
b: (diffuse * 255. * 0.9 + 0.1 * 255.) as u8,
a: 0,
},
);
}
(None, Some(dist)) => {
let n = [
ray2.origin[0] + ray2.direction[0] * dist,
ray2.origin[1] + ray2.direction[1] * dist,
ray2.origin[2] + ray2.direction[2] * dist,
];
let normal = sphere.get_normal(n);
let light = [n[0] - 10., n[1] - 10., n[2] + 10.];
let scalar = (light[0].powi(2) + light[1].powi(2) + light[2].powi(2)).sqrt();
let light_d = [light[0] / scalar, light[1] / scalar, light[2] / scalar];
let mut diffuse =
normal[0] * light_d[0] + normal[1] * light_d[1] + normal[2] * light_d[2];
if diffuse < 0. {
diffuse = 0.;
}
put_pixel(
&mut *data,
x,
y,
Color {
r: 0,
g: (diffuse * 255. * 0.9 + 0.1 * 255.) as u8,
b: (diffuse * 255. * 0.9 + 0.1 * 255.) as u8,
a: 0,
},
);
}
(Some(dist1), Some(dist2)) => {
let n;
if dist1 < dist2 {
n = [
ray.origin[0] + ray.direction[0] * dist1,
ray.origin[1] + ray.direction[1] * dist1,
ray.origin[2] + ray.direction[2] * dist1,
];
} else {
n = [
ray2.origin[0] + ray2.direction[0] * dist2,
ray2.origin[1] + ray2.direction[1] * dist2,
ray2.origin[2] + ray2.direction[2] * dist2,
];
}
let normal = sphere.get_normal(n);
let light = [n[0] - 10., n[1] - 10., n[2] + 10.];
let scalar = (light[0].powi(2) + light[1].powi(2) + light[2].powi(2)).sqrt();
let light_d = [light[0] / scalar, light[1] / scalar, light[2] / scalar];
let mut diffuse =
normal[0] * light_d[0] + normal[1] * light_d[1] + normal[2] * light_d[2];
if diffuse < 0. {
diffuse = 0.;
}
put_pixel(
&mut *data,
x,
y,
Color {
r: 0,
g: (diffuse * 255. * 0.9 + 0.1 * 255.) as u8,
b: (diffuse * 255. * 0.9 + 0.1 * 255.) as u8,
a: 0,
},
);
}
(None, None) => {
put_pixel(
&mut *data,
x,
y,
Color {
r: 0,
g: 0,
b: 0,
a: 0,
},
);
}
}
}
}
}