export_frame/
export_frame.rs

1use nes_sim::NES;
2use nes_sim::headless::write_frame_ppm;
3use std::env;
4use std::path::Path;
5use std::process::ExitCode;
6
7fn usage(program: &str) {
8    eprintln!("Usage: {program} <rom-path> <output-ppm> [frames]");
9    eprintln!(r#"Example: {program} "roms/mmc1/Rockman2(J).nes" "out/rockman2.ppm" 180"#);
10}
11
12fn main() -> ExitCode {
13    let mut args = env::args();
14    let program = args.next().unwrap_or_else(|| "export_frame".to_string());
15
16    let Some(rom_path) = args.next() else {
17        usage(&program);
18        return ExitCode::from(2);
19    };
20    let Some(output_path) = args.next() else {
21        usage(&program);
22        return ExitCode::from(2);
23    };
24    let frames = match args.next() {
25        Some(value) => match value.parse::<usize>() {
26            Ok(frames) => frames,
27            Err(error) => {
28                eprintln!("invalid frame count {value:?}: {error}");
29                return ExitCode::from(2);
30            }
31        },
32        None => 120,
33    };
34
35    let rom = match std::fs::read(&rom_path) {
36        Ok(rom) => rom,
37        Err(error) => {
38            eprintln!("failed to read ROM {rom_path:?}: {error}");
39            return ExitCode::from(1);
40        }
41    };
42
43    let mut nes = NES::new();
44    if let Err(error) = nes.load_cartridge_ines(&rom) {
45        eprintln!("failed to load ROM {rom_path:?}: {error}");
46        return ExitCode::from(1);
47    }
48    nes.reset();
49
50    for _ in 0..frames {
51        nes.run_frame();
52    }
53
54    if let Some(parent) = Path::new(&output_path).parent()
55        && !parent.as_os_str().is_empty()
56    {
57        if let Err(error) = std::fs::create_dir_all(parent) {
58            eprintln!("failed to create output directory {:?}: {}", parent, error);
59            return ExitCode::from(1);
60        }
61    }
62
63    if let Err(error) = write_frame_ppm(&output_path, nes.video_frame()) {
64        eprintln!("failed to write PPM {output_path:?}: {error}");
65        return ExitCode::from(1);
66    }
67
68    println!(
69        "wrote frame {} from {} to {}",
70        nes.frame_number(),
71        rom_path,
72        output_path
73    );
74    ExitCode::SUCCESS
75}
export_frame/export_frame.rs

export_frame/
export_frame.rs
