Remove `image` abstractions in `iced_graphics`

1 files changed, 91 insertions, 7 deletions

diff --git a/graphics/src/image.rs b/graphics/src/image.rs
index 04f4ff9d..2f634252 100644
--- a/graphics/src/image.rs
+++ b/graphics/src/image.rs
@@ -1,10 +1,94 @@
-//! Render images.
-#[cfg(feature = "image_rs")]
-pub mod raster;
+//! Load and operate on images.
+use crate::core::image::{Data, Handle};
 
-#[cfg(feature = "svg")]
-pub mod vector;
+use bitflags::bitflags;
 
-pub mod storage;
+pub use ::image as image_rs;
 
-pub use storage::Storage;
+pub fn load(handle: &Handle) -> image_rs::ImageResult<image_rs::DynamicImage> {
+    match handle.data() {
+        Data::Path(path) => {
+            let image = ::image::open(path)?;
+
+            let operation = std::fs::File::open(path)
+                .ok()
+                .map(std::io::BufReader::new)
+                .and_then(|mut reader| Operation::from_exif(&mut reader).ok())
+                .unwrap_or_else(Operation::empty);
+
+            Ok(operation.perform(image))
+        }
+        Data::Bytes(bytes) => {
+            let image = ::image::load_from_memory(bytes)?;
+            let operation =
+                Operation::from_exif(&mut std::io::Cursor::new(bytes))
+                    .ok()
+                    .unwrap_or_else(Operation::empty);
+
+            Ok(operation.perform(image))
+        }
+        Data::Rgba {
+            width,
+            height,
+            pixels,
+        } => {
+            if let Some(image) = image_rs::ImageBuffer::from_vec(
+                *width,
+                *height,
+                pixels.to_vec(),
+            ) {
+                Ok(image_rs::DynamicImage::ImageRgba8(image))
+            } else {
+                Err(image_rs::error::ImageError::Limits(
+                    image_rs::error::LimitError::from_kind(
+                        image_rs::error::LimitErrorKind::DimensionError,
+                    ),
+                ))
+            }
+        }
+    }
+}
+
+bitflags! {
+    struct Operation: u8 {
+        const FLIP_HORIZONTALLY = 0b001;
+        const ROTATE_180 = 0b010;
+        const FLIP_DIAGONALLY = 0b100;
+    }
+}
+
+impl Operation {
+    // Meaning of the returned value is described e.g. at:
+    // https://magnushoff.com/articles/jpeg-orientation/
+    fn from_exif<R>(reader: &mut R) -> Result<Self, exif::Error>
+    where
+        R: std::io::BufRead + std::io::Seek,
+    {
+        let exif = exif::Reader::new().read_from_container(reader)?;
+
+        Ok(exif
+            .get_field(exif::Tag::Orientation, exif::In::PRIMARY)
+            .and_then(|field| field.value.get_uint(0))
+            .and_then(|value| u8::try_from(value).ok())
+            .and_then(|value| Self::from_bits(value.saturating_sub(1)))
+            .unwrap_or_else(Self::empty))
+    }
+
+    fn perform(self, mut image: image::DynamicImage) -> image::DynamicImage {
+        use image::imageops;
+
+        if self.contains(Self::FLIP_DIAGONALLY) {
+            imageops::flip_vertical_in_place(&mut image)
+        }
+
+        if self.contains(Self::ROTATE_180) {
+            imageops::rotate180_in_place(&mut image);
+        }
+
+        if self.contains(Self::FLIP_HORIZONTALLY) {
+            imageops::flip_horizontal_in_place(&mut image);
+        }
+
+        image
+    }
+}