lj_rust/examples/etherdream.rs
2023-07-24 17:28:18 +02:00

151 lines
4.1 KiB
Rust

extern crate ether_dream;
use ether_dream::dac;
fn main() {
println!("Listening for an Ether Dream DAC...");
let (dac_broadcast, source_addr) = ether_dream::recv_dac_broadcasts()
.expect("failed to bind to UDP socket")
.filter_map(Result::ok)
.next()
.unwrap();
let mac_address = dac::MacAddress(dac_broadcast.mac_address);
println!(
"Discovered DAC \"{}\" at \"{}\"! Connecting...",
mac_address, source_addr
);
// Establish the TCP connection.
let mut stream = dac::stream::connect(&dac_broadcast, source_addr.ip().clone()).unwrap();
// If we want to create an animation (in our case a moving sine wave) we need a frame rate.
let frames_per_second = 60.0;
// Lets use the DAC at an eighth the maximum scan rate.
let points_per_second = stream.dac().max_point_rate / 32;
// Determine the number of points per frame given our target frame and point rates.
let points_per_frame = (points_per_second as f32 / frames_per_second) as u16;
println!(
"Preparing for playback:\n\tframe_hz: {}\n\tpoint_hz: {}\n\tpoints_per_frame: {}\n",
frames_per_second, points_per_second, points_per_frame
);
// Prepare the DAC's playback engine and await the repsonse.
stream
.queue_commands()
.prepare_stream()
.submit()
.err()
.map(|err| {
eprintln!(
"err occurred when submitting PREPARE_STREAM \
command and listening for response: {}",
err
);
});
println!("Beginning playback!");
// The sine wave used to generate points.
let mut sine_wave = SineWave {
point: 0,
points_per_frame,
frames_per_second,
};
// Queue the initial frame and tell the DAC to begin producing output.
let n_points = points_to_generate(stream.dac());
stream
.queue_commands()
.data(sine_wave.by_ref().take(n_points))
.begin(0, points_per_second)
.submit()
.err()
.map(|err| {
eprintln!(
"err occurred when submitting initial DATA and BEGIN \
commands and listening for response: {}",
err
);
});
eprintln!("Stream dac{:?}", stream.dac());
// Loop and continue to send points forever.
loop {
// Determine how many points the DAC can currently receive.
let n_points = points_to_generate(stream.dac());
if let Err(err) = stream
.queue_commands()
.data(sine_wave.by_ref().take(n_points))
.submit()
{
eprintln!(
"err occurred when submitting DATA command and listening \
for response: {}",
err
);
break;
}
}
// Tell the DAC to stop producing output and return to idle. Wait for the response.
//
// Note that the DAC is commanded to stop on `Drop` if this is not called and any errors
// produced are ignored.
stream
.queue_commands()
.stop()
.submit()
.expect("err occurred when submitting STOP command and listening for response");
}
// Determine the number of points needed to fill the DAC.
fn points_to_generate(dac: &ether_dream::dac::Dac) -> usize {
dac.buffer_capacity as usize - 1 - dac.status.buffer_fullness as usize
}
// An iterator that endlessly generates a sine wave of DAC points.
//
// The sine wave oscillates at a rate of once per second.
struct SineWave {
point: u32,
points_per_frame: u16,
frames_per_second: f32,
}
impl Iterator for SineWave {
type Item = ether_dream::protocol::DacPoint;
fn next(&mut self) -> Option<Self::Item> {
let coloured_points_per_frame = self.points_per_frame - 1;
let i = (self.point % self.points_per_frame as u32) as u16;
let hz = 1.0;
let fract = i as f32 / coloured_points_per_frame as f32;
let phase = (self.point as f32 / coloured_points_per_frame as f32) / self.frames_per_second;
let amp = (hz * (fract + phase) * 2.0 * std::f32::consts::PI).sin();
let (r, g, b) = match i {
i if i == coloured_points_per_frame || i < 13 => (0, 0, 0),
_ => (std::u16::MAX, std::u16::MAX, std::u16::MAX),
};
let x_min = std::i16::MIN;
let x_max = std::i8::MAX as i16;
let x = (x_min as f32 + fract * (x_max as f32 - x_min as f32)) as i16;
let y = (amp * x_max as f32) as i16;
let control = 0;
let (u1, u2) = (0, 0);
let p = ether_dream::protocol::DacPoint {
control,
x,
y,
i,
r,
g,
b,
u1,
u2,
};
self.point += 1;
Some(p)
}
}