1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182


use glutin::*;
use crate::window::frame_input;
use crate::gl;

#[derive(Debug)]
pub enum Error {
    WindowCreationError(glutin::CreationError),
    ContextError(glutin::ContextError)
}

impl From<glutin::CreationError> for Error {
    fn from(other: glutin::CreationError) -> Self {
        Error::WindowCreationError(other)
    }
}

impl From<glutin::ContextError> for Error {
    fn from(other: glutin::ContextError) -> Self {
        Error::ContextError(other)
    }
}

pub struct Window
{
    gl_window: GlWindow,
    events_loop: EventsLoop,
    gl: crate::Gl
}

impl Window
{
    pub fn new_default(title: &str) -> Result<Window, Error>
    {
        Window::new(title, 1024, 512)
    }

    pub fn new(title: &str, width: u32, height: u32) -> Result<Window, Error>
    {
        let window = WindowBuilder::new()
            .with_title(title)
            .with_dimensions(dpi::LogicalSize::new(width as f64, height as f64));

        let events_loop = EventsLoop::new();

        let context = ContextBuilder::new().with_vsync(true);

        let gl_window = GlWindow::new(window, context, &events_loop)?;

        unsafe {
            gl_window.make_current()?;
        }
        let gl = gl::Glstruct::load_with(|s| gl_window.get_proc_address(s) as *const std::os::raw::c_void);
        Ok(Window {gl_window, events_loop, gl})
    }

    pub fn render_loop<F: 'static>(&mut self, mut callback: F) -> Result<(), Error>
        where F: FnMut(frame_input::FrameInput)
    {
        let mut last_time = std::time::Instant::now();
        let mut count = 0;
        let mut accumulated_time = 0.0;
        let mut error = Ok(());
        let mut exit = false;
        while error.is_ok() && !exit {
            let mut events = Vec::new();
            self.events_loop.poll_events(|event| {
                exit = Self::handle_window_close_events(&event);
                if let Some(e) = Self::map_event(&event)
                {
                    events.push(e);
                }
            });

            let now = std::time::Instant::now();
            let duration = now.duration_since(last_time);
            last_time = now;
            let elapsed_time = duration.as_secs() as f64 * 1000.0 + duration.subsec_nanos() as f64 * 1e-6;
            accumulated_time += elapsed_time;
            count += 1;
            if accumulated_time > 1000.0 {
                println!("FPS: {}", count as f64 / (accumulated_time * 0.001));
                count = 0;
                accumulated_time = 0.0;
            }

            let (screen_width, screen_height) = self.framebuffer_size();
            let (window_width, window_height) = self.size();
            let frame_input = frame_input::FrameInput {events, elapsed_time, screen_width, screen_height, window_width, window_height};
            callback(frame_input);
            error = self.gl_window.swap_buffers();
        }
        error?;
        Ok(())
    }

    pub fn framebuffer_size(&self) -> (usize, usize)
    {
        let t: (u32, u32) = self.gl_window.get_inner_size().unwrap().to_physical(self.gl_window.get_hidpi_factor()).into();
        (t.0 as usize, t.1 as usize)
    }

    pub fn size(&self) -> (usize, usize)
    {
        let t: (u32, u32) = self.gl_window.get_inner_size().unwrap().into();
        (t.0 as usize, t.1 as usize)
    }

    pub fn aspect(&self) -> f32 {
        let (width, height) = self.framebuffer_size();
        width as f32 / height as f32
    }

    pub fn gl(&self) -> crate::Gl
    {
        self.gl.clone()
    }

    fn map_event(event: &Event) -> Option<frame_input::Event>
    {
        static mut CURSOR_POS: Option<(f64, f64)> = None;
        match event {
            Event::WindowEvent{ event, .. } => match event {
                WindowEvent::KeyboardInput {input, ..} => {
                    if let Some(keycode) = input.virtual_keycode {
                        let state = if input.state == ElementState::Pressed {frame_input::State::Pressed} else {frame_input::State::Released};
                        return Some(frame_input::Event::Key {state, kind: format!("{:?}", keycode)});
                    }
                },
                WindowEvent::MouseWheel {delta, ..} => {
                    match delta {
                        MouseScrollDelta::LineDelta(_, y) => {
                            return Some(frame_input::Event::MouseWheel { delta: *y as f64 });
                        },
                        MouseScrollDelta::PixelDelta(logical_position) => {
                            return Some(frame_input::Event::MouseWheel { delta: logical_position.y });
                        }
                    }
                },
                WindowEvent::MouseInput {state, button, ..} => {
                    if let Some(position) = unsafe {CURSOR_POS}
                    {
                        let state = if *state == ElementState::Pressed {frame_input::State::Pressed} else {frame_input::State::Released};
                        let button = match button {
                            MouseButton::Left => Some(frame_input::MouseButton::Left),
                            MouseButton::Middle => Some(frame_input::MouseButton::Middle),
                            MouseButton::Right => Some(frame_input::MouseButton::Right),
                            _ => None
                        };
                        return button.map(|b| frame_input::Event::MouseClick { state, button: b, position });
                    }
                },
                WindowEvent::CursorMoved {position, ..} => {
                    unsafe {
                        CURSOR_POS = Some((position.x, position.y));
                    }
                },
                _ => ()
            },
            Event::DeviceEvent{ event, .. } => match event {
                DeviceEvent::MouseMotion {delta} => {
                    return Some(frame_input::Event::MouseMotion {delta: *delta});
                },
                _ => {}
            }
            _ => ()
        }
        None
    }

    fn handle_window_close_events(event: &Event) -> bool
    {
        match event {
            Event::WindowEvent{ event, .. } => match event {
                WindowEvent::CloseRequested => true,
                WindowEvent::KeyboardInput {input, ..} => Some(VirtualKeyCode::Escape) == input.virtual_keycode,
                _ => false
            },
            _ => false
        }
    }
}