better looking snow

This commit is contained in:
lifning 2021-10-17 22:23:35 -07:00
parent f53aef4f67
commit 5c0dd5558e
1 changed files with 16 additions and 9 deletions

View File

@ -9,7 +9,7 @@ use sdl2::render::{WindowCanvas, BlendMode};
use sdl2::image::ImageRWops;
use sdl2::surface::Surface;
use sdl2::pixels::{Color, PixelFormatEnum};
use sdl2::rect::Rect;
use sdl2::rect::Point;
use rand::{SeedableRng, Rng};
use rand_xoshiro::Xoshiro128Plus;
@ -44,7 +44,7 @@ struct Zretro {
font: Surface<'static>,
rng: Xoshiro128Plus,
ui_bg: Option<Surface<'static>>,
snowflakes: Vec<Rect>,
snowflakes: Vec<Point>,
}
const FONT_PNG: &'static [u8] = include_bytes!("lifont.png");
@ -101,10 +101,10 @@ impl Zretro {
let mut ui_bg = Surface::new(geometry.base_width, geometry.base_height, PixelFormatEnum::ABGR8888)?;
ui_bg.fill_rect(None, Color::RGBA(0, 0, 128, 128))?;
let snowflakes = (0..100).into_iter()
.map(|_| Rect::new(
.map(|_| Point::new(
rng.gen_range(0..ui_bg.width() as i32),
rng.gen_range(0..ui_bg.height() as i32),
2, 2))
))
.collect();
Ok(Zretro {
@ -122,15 +122,22 @@ impl Zretro {
ui_bg.fill_rect(None, Color::RGBA(0, 0, 128, 128))?;
let w = ui_bg.width() as i32;
let h = ui_bg.height() as i32;
for flake in &mut self.snowflakes {
let x = flake.x() + self.rng.gen_range(-1..=1);
let halflen = self.snowflakes.len() / 2;
for flake in &mut self.snowflakes[..halflen] {
let x = flake.x() + self.rng.gen_range(0..=1);
let y = flake.y() + 1;
flake.set_x(x % w);
flake.set_y(y % h);
*flake = Point::new(x % w, y % h);
}
for flake in &mut self.snowflakes[halflen..] {
let x = flake.x();
let y = flake.y() + self.rng.gen_range(0..=1);
*flake = Point::new(x, y % h);
}
let mut ui_canvas = ui_bg.into_canvas()?;
ui_canvas.set_draw_color(Color::RGBA(255, 255, 255, 160));
ui_canvas.draw_rects(&self.snowflakes[..])?;
ui_canvas.draw_points(&self.snowflakes[..halflen])?;
ui_canvas.set_draw_color(Color::RGBA(255, 255, 255, 128));
ui_canvas.draw_points(&self.snowflakes[halflen..])?;
self.ui_bg = Some(ui_canvas.into_surface());
Ok(())
}