ruffle/exporter/src/main.rs

use futures::executor::block_on;
use image::RgbaImage;
use ruffle_core::backend::audio::NullAudioBackend;
use ruffle_core::backend::input::NullInputBackend;
use ruffle_core::backend::navigator::NullNavigatorBackend;
use ruffle_core::tag_utils::SwfMovie;
use ruffle_core::Player;
use ruffle_render_wgpu::target::TextureTarget;
use ruffle_render_wgpu::WgpuRenderBackend;
use std::error::Error;
use std::fs::create_dir_all;
use std::path::{Path, PathBuf};
use structopt::StructOpt;
use walkdir::{DirEntry, WalkDir};

#[derive(StructOpt, Debug)]
struct Opt {
    /// The file or directory of files to export frames from
    #[structopt(name = "swf", parse(from_os_str))]
    swf: PathBuf,

    /// The file or directory (if multiple frames/files) to store the capture in.
    /// The default value will either be:
    /// - If given one swf and one frame, the name of the swf + ".png"
    /// - If given one swf and multiple frames, the name of the swf as a directory
    /// - If given multiple swfs, this field is required.
    #[structopt(name = "output", parse(from_os_str))]
    output_path: Option<PathBuf>,

    /// Number of frames to capture per file
    #[structopt(short = "f", long = "frames", default_value = "1")]
    frames: u32,
}

fn take_screenshot(
    adapter: &wgpu::Adapter,
    swf_path: &Path,
    frames: u32,
) -> Result<Vec<RgbaImage>, Box<dyn std::error::Error>> {
    let movie = SwfMovie::from_path(swf_path)?;

    let (device, queue) = block_on(adapter.request_device(&wgpu::DeviceDescriptor {
        extensions: wgpu::Extensions {
            anisotropic_filtering: false,
        },
        limits: wgpu::Limits::default(),
    }));
    let target = TextureTarget::new(&device, (movie.width(), movie.height()));
    let player = Player::new(
        Box::new(WgpuRenderBackend::new(device, queue, target)?),
        Box::new(NullAudioBackend::new()),
        Box::new(NullNavigatorBackend::new()),
        Box::new(NullInputBackend::new()),
        movie,
    )?;

    let mut result = Vec::new();
    for i in 0..frames {
        player.lock().unwrap().run_frame();
        player.lock().unwrap().render();

        let mut player = player.lock().unwrap();
        let renderer = player
            .renderer_mut()
            .downcast_mut::<WgpuRenderBackend<TextureTarget>>()
            .unwrap();
        let target = renderer.target();
        if let Some(image) = target.capture(renderer.device()) {
            result.push(image);
        } else {
            return Err(format!("Unable to capture frame {} of {:?}", i, swf_path).into());
        }
    }

    Ok(result)
}

fn find_files(root: &Path) -> Vec<DirEntry> {
    let mut results = Vec::new();

    for entry in WalkDir::new(root)
        .follow_links(true)
        .into_iter()
        .filter_map(|e| e.ok())
    {
        let f_name = entry.file_name().to_string_lossy();

        if f_name.ends_with(".swf") {
            results.push(entry);
        }
    }

    results
}

fn capture_single_swf(
    adapter: wgpu::Adapter,
    swf: &Path,
    frames: u32,
    output: Option<PathBuf>,
) -> Result<(), Box<dyn Error>> {
    let output = output.unwrap_or_else(|| {
        let mut result = PathBuf::new();
        if frames == 1 {
            result.set_file_name(swf.file_stem().unwrap());
            result.set_extension("png");
        } else {
            result.set_file_name(swf.file_stem().unwrap());
        }
        result
    });

    if frames > 1 {
        let _ = create_dir_all(&output);
    }

    let frames = take_screenshot(&adapter, &swf, frames)?;

    if frames.len() == 1 {
        frames.get(0).unwrap().save(&output)?;
        println!(
            "Saved first frame of {} to {}",
            swf.to_string_lossy(),
            output.to_string_lossy()
        );
    } else {
        for (frame, image) in frames.iter().enumerate() {
            let mut path = PathBuf::from(&output);
            path.push(format!("{}.png", frame));
            image.save(&path)?;
        }
        println!(
            "Saved first {} frames of {} to {}",
            frames.len(),
            swf.to_string_lossy(),
            output.to_string_lossy()
        );
    }

    Ok(())
}

fn capture_multiple_swfs(
    adapter: wgpu::Adapter,
    directory: &Path,
    frames: u32,
    output: &Path,
) -> Result<(), Box<dyn Error>> {
    let files = find_files(directory);

    for file in &files {
        let frames = take_screenshot(&adapter, &file.path(), frames)?;
        let mut relative_path = file
            .path()
            .strip_prefix(directory)
            .unwrap_or_else(|_| &file.path())
            .to_path_buf();

        if frames.len() == 1 {
            let mut destination = PathBuf::from(output);
            relative_path.set_extension("png");
            destination.push(relative_path);
            if let Some(parent) = destination.parent() {
                let _ = create_dir_all(parent);
            }
            frames.get(0).unwrap().save(&destination)?;
        } else {
            let mut parent = PathBuf::from(output);
            relative_path.set_extension("");
            parent.push(&relative_path);
            let _ = create_dir_all(&parent);
            for (frame, image) in frames.iter().enumerate() {
                let mut destination = parent.clone();
                destination.push(format!("{}.png", frame));
                image.save(&destination)?;
            }
        }
    }

    if frames == 1 {
        println!(
            "Saved first frame of {} files to {}",
            files.len(),
            output.to_string_lossy()
        );
    } else {
        println!(
            "Saved first {} frames of {} files to {}",
            frames,
            files.len(),
            output.to_string_lossy()
        );
    }

    Ok(())
}

fn main() -> Result<(), Box<dyn Error>> {
    let opt: Opt = Opt::from_args();
    let adapter = block_on(wgpu::Adapter::request(
        &wgpu::RequestAdapterOptions {
            power_preference: wgpu::PowerPreference::Default,
            compatible_surface: None,
        },
        wgpu::BackendBit::PRIMARY,
    ))
    .ok_or_else(|| {
        "This tool requires hardware acceleration, but no compatible graphics device was found."
    })?;

    if opt.swf.is_file() {
        capture_single_swf(adapter, &opt.swf, opt.frames, opt.output_path)?;
    } else if let Some(output) = opt.output_path {
        capture_multiple_swfs(adapter, &opt.swf, opt.frames, &output)?;
    } else {
        return Err("Output directory is required when exporting multiple files.".into());
    }

    Ok(())
}