feat(engine): add asset management

1 files changed, 184 insertions, 0 deletions

diff --git a/engine/src/image.rs b/engine/src/image.rs
new file mode 100644
index 0000000..a4513ae
--- /dev/null
+++ b/engine/src/image.rs
@@ -0,0 +1,184 @@
+use std::fs::File;
+use std::io::BufReader;
+use std::path::Path;
+
+use image_rs::GenericImageView as _;
+
+use crate::asset::{Assets, Submitter as AssetSubmitter};
+use crate::color::Color;
+use crate::data_types::dimens::Dimens;
+use crate::util::builder;
+
+#[derive(Debug)]
+pub struct Image
+{
+    inner: image_rs::DynamicImage,
+}
+
+impl Image
+{
+    pub fn open(path: impl AsRef<Path>) -> Result<Self, Error>
+    {
+        let buffered_reader =
+            BufReader::new(File::open(&path).map_err(Error::ReadFailed)?);
+
+        let image_reader = image_rs::io::Reader::with_format(
+            buffered_reader,
+            image_rs::ImageFormat::from_path(path)
+                .map_err(|_| Error::UnsupportedFormat)?,
+        );
+
+        Ok(Self {
+            inner: image_reader
+                .decode()
+                .map_err(|err| Error::DecodeFailed(DecodeError(err)))?,
+        })
+    }
+
+    pub fn from_color(dimens: impl Into<Dimens<u32>>, color: impl Into<Color<u8>>)
+        -> Self
+    {
+        let dimens: Dimens<u32> = dimens.into();
+
+        let color: Color<u8> = color.into();
+
+        Self {
+            inner: image_rs::RgbImage::from_pixel(
+                dimens.width,
+                dimens.height,
+                image_rs::Rgb([color.red, color.green, color.blue]),
+            )
+            .into(),
+        }
+    }
+
+    pub fn dimensions(&self) -> Dimens<u32>
+    {
+        self.inner.dimensions().into()
+    }
+
+    pub fn color_type(&self) -> ColorType
+    {
+        self.inner.color().into()
+    }
+
+    pub fn as_bytes(&self) -> &[u8]
+    {
+        self.inner.as_bytes()
+    }
+}
+
+builder! {
+#[builder(name = SettingsBuilder, derives=(Debug, Clone))]
+#[derive(Debug, Default, Clone)]
+#[non_exhaustive]
+pub struct Settings {
+}
+}
+
+impl Settings
+{
+    pub fn builder() -> SettingsBuilder
+    {
+        SettingsBuilder::default()
+    }
+}
+
+impl Default for SettingsBuilder
+{
+    fn default() -> Self
+    {
+        Settings::default().into()
+    }
+}
+
+/// An enumeration over supported color types and bit depths
+#[derive(Copy, PartialEq, Eq, Debug, Clone, Hash)]
+#[non_exhaustive]
+pub enum ColorType
+{
+    /// Pixel is 8-bit luminance
+    L8,
+
+    /// Pixel is 8-bit luminance with an alpha channel
+    La8,
+
+    /// Pixel contains 8-bit R, G and B channels
+    Rgb8,
+
+    /// Pixel is 8-bit RGB with an alpha channel
+    Rgba8,
+
+    /// Pixel is 16-bit luminance
+    L16,
+
+    /// Pixel is 16-bit luminance with an alpha channel
+    La16,
+
+    /// Pixel is 16-bit RGB
+    Rgb16,
+
+    /// Pixel is 16-bit RGBA
+    Rgba16,
+
+    /// Pixel is 32-bit float RGB
+    Rgb32F,
+
+    /// Pixel is 32-bit float RGBA
+    Rgba32F,
+}
+
+impl From<image_rs::ColorType> for ColorType
+{
+    fn from(color_type: image_rs::ColorType) -> Self
+    {
+        match color_type {
+            image_rs::ColorType::L8 => Self::L8,
+            image_rs::ColorType::La8 => Self::La8,
+            image_rs::ColorType::Rgb8 => Self::Rgb8,
+            image_rs::ColorType::Rgba8 => Self::Rgba8,
+            image_rs::ColorType::L16 => Self::L16,
+            image_rs::ColorType::La16 => Self::La16,
+            image_rs::ColorType::Rgb16 => Self::Rgb16,
+            image_rs::ColorType::Rgba16 => Self::Rgba16,
+            image_rs::ColorType::Rgb32F => Self::Rgb32F,
+            image_rs::ColorType::Rgba32F => Self::Rgba32F,
+            _ => {
+                panic!("Unrecognized image_rs::ColorType variant");
+            }
+        }
+    }
+}
+
+pub fn set_asset_importers(assets: &mut Assets)
+{
+    assets.set_importer::<_, _>(["png", "jpg"], import_asset);
+}
+
+#[derive(Debug, thiserror::Error)]
+pub enum Error
+{
+    #[error("Failed to read image file")]
+    ReadFailed(#[source] std::io::Error),
+
+    #[error("Failed to decode image")]
+    DecodeFailed(DecodeError),
+
+    #[error("Unsupported image format")]
+    UnsupportedFormat,
+}
+
+#[derive(Debug, thiserror::Error)]
+#[error(transparent)]
+pub struct DecodeError(image_rs::ImageError);
+
+fn import_asset(
+    asset_submitter: &mut AssetSubmitter<'_>,
+    path: &Path,
+    _settings: Option<&'_ Settings>,
+) -> Result<(), Error>
+{
+    asset_submitter.submit_store::<Image>(Image::open(path)?);
+
+    Ok(())
+}