use ggez;
use nalgebra;
use ggez::event;
use ggez::graphics::{self, Color};
use ggez::{Context, GameResult};
use nalgebra as na;
use std::env;
use std::path;
struct MainState {
text: graphics::Text,
canvas: graphics::Canvas,
frames: usize,
draw_with_canvas: bool,
}
impl MainState {
fn new(ctx: &mut Context) -> GameResult<MainState> {
let font = graphics::Font::new(ctx, "/DejaVuSerif.ttf")?;
let text = graphics::Text::new(("Hello world!", font, 48.0));
let canvas = graphics::Canvas::with_window_size(ctx)?;
let s = MainState {
text,
canvas,
draw_with_canvas: false,
frames: 0,
};
Ok(s)
}
}
impl event::EventHandler for MainState {
fn update(&mut self, _ctx: &mut Context) -> GameResult {
Ok(())
}
fn draw(&mut self, ctx: &mut Context) -> GameResult {
let dest_point = na::Point2::new(10.0, 10.0);
if self.draw_with_canvas {
println!("Drawing with canvas");
graphics::clear(ctx, graphics::Color::from((64, 0, 0, 0)));
graphics::set_canvas(ctx, Some(&self.canvas));
graphics::clear(ctx, graphics::Color::from((255, 255, 255, 128)));
graphics::draw(
ctx,
&self.text,
graphics::DrawParam::new()
.dest(dest_point)
.color(Color::from((0, 0, 0, 255))),
)?;
graphics::set_canvas(ctx, None);
graphics::draw(
ctx,
&self.canvas,
graphics::DrawParam::new().color(Color::from((255, 255, 255, 128))),
)?;
} else {
println!("Drawing without canvas");
graphics::set_canvas(ctx, None);
graphics::clear(ctx, [0.25, 0.0, 0.0, 1.0].into());
graphics::draw(
ctx,
&self.text,
graphics::DrawParam::new()
.dest(dest_point)
.color(Color::from((192, 128, 64, 255))),
)?;
}
graphics::present(ctx)?;
self.frames += 1;
if (self.frames % 100) == 0 {
println!("FPS: {}", ggez::timer::fps(ctx));
}
Ok(())
}
fn key_down_event(
&mut self,
_ctx: &mut Context,
_keycode: ggez::event::KeyCode,
_keymod: ggez::event::KeyMods,
repeat: bool,
) {
if !repeat {
self.draw_with_canvas = !self.draw_with_canvas;
println!("Canvas on: {}", self.draw_with_canvas);
}
}
}
pub fn main() -> GameResult {
let resource_dir = if let Ok(manifest_dir) = env::var("CARGO_MANIFEST_DIR") {
let mut path = path::PathBuf::from(manifest_dir);
path.push("resources");
path
} else {
path::PathBuf::from("./resources")
};
let cb = ggez::ContextBuilder::new("hello_canvas", "ggez").add_resource_path(resource_dir);
let (ctx, event_loop) = &mut cb.build()?;
let state = &mut MainState::new(ctx)?;
event::run(ctx, event_loop, state)
}