描画環境 周りのリファクタリング(Rust製ラスタライザ)

目次

ファイル分離

次のメソッドを持つ

draw_line(p1, p2, color)

code:tree

src

| canvas.rs

| canvas

| | base.rs

| | draw_line.rs

| util.rs

| util

| | point2.rs

| | vec3.rs

| main.rs

code:util.rs

mod point2;

mod vec3;

pub use point2::*;

pub use vec3::*;

pub fn in_range<T: PartialOrd>(begin: T, x: T, end: T) -> bool { ... }

pub type Throwable<T> = Result<T, Box<dyn std::error::Error>>;

code:rs

// Canvas構造体の定義とdraw_pixel関数などの基本メソッドを定義

// newメソッド・updateメソッドでminifbの初期化・更新を行う。

mod base;

// 線分描画アルゴリズムをCanvasのメソッドとして定義

mod draw_line;

pub use base::Canvas;

code:main.rs

mod util;

mod canvas;

use std::f64::consts::PI;

use canvas::Canvas;

use util::{Throwable, Color, Point2};

const WIDTH: usize = 640;

const HEIGHT: usize = 480;

fn main() -> Throwable<()> {

let mut canvas = Canvas::new(WIDTH, HEIGHT)?;

while canvas.update()? {

for i in 0..50 {

let theta = -PI/2.0 + (i as f64) * 2.0*PI / 50.0;

let r = (HEIGHT as f64) / 2.0;

let p1 = Point2::new((WIDTH as i32) / 2, (HEIGHT as i32) / 2);

let p2 = Point2::new(

(p1.x as f64 + r * f64::cos(theta)).floor() as i32,

(p1.y as f64 + r * f64::sin(theta)).floor() as i32

);

canvas.draw_line(&p1, &p2, &Color::new(1., 1., 1.));

}

}

Ok(())

}