feat(imaging): add pure-Rust JPEG 2000 backend (#109)

crates/libremetaverse/Cargo.toml

@@ -11,6 +11,7 @@ description = "Rust rewrite shell for the LibreMetaverse client library"
 default = ["dds-bc67"]
 dds-bc67 = ["dep:bcdec_rs"]
 jpeg2000 = ["libremetaverse-imaging/jpeg2000"]
+rust-j2k = ["libremetaverse-imaging/rust-j2k"]
 vorbis = ["dep:vorbis_rs"]
 
 [dependencies]

crates/libremetaverse/README.md

@@ -15,10 +15,10 @@ they use those APIs directly.
 
 | Crate | Choose it for | Features or system boundary |
 | --- | --- | --- |
-| `libremetaverse` | Grid client, login, network, agents, inventory, assets, appearance, world, and social APIs | Default pure-Rust BC6H/BC7; optional `jpeg2000` and `vorbis` |
+| `libremetaverse` | Grid client, login, network, agents, inventory, assets, appearance, world, and social APIs | Default pure-Rust BC6H/BC7; optional `jpeg2000`, `rust-j2k`, and `vorbis` |
 | `libremetaverse-types` | UUIDs, vectors, matrices, colors, cancellation, compatibility collections, and boundary types | Pure Rust |
 | `libremetaverse-structured-data` | LLSD/OSD XML, JSON, binary, and notation | Pure Rust |
-| `libremetaverse-imaging` | Managed images, TGA/DDS, codec traits | Optional `jpeg2000` |
+| `libremetaverse-imaging` | Managed images, TGA/DDS, codec traits | Optional `jpeg2000` or pure-Rust `rust-j2k` |
 | `libremetaverse-imaging-skia` | Common raster formats through Skia | Optional `skia`; native Skia build/cache |
 | `libremetaverse-prim-mesher` | Legacy prim and sculpt geometry | Pure Rust |
 | `libremetaverse-rendering-simple` | Deterministic reference geometry | Pure Rust |
@@ -190,6 +190,7 @@ The default client build needs no image-codec system library. Optional native
 features require:
 
 - `OpenJPEG` 2.5.4 or newer for `jpeg2000`;
+- no native prerequisite for the pure-Rust `rust-j2k` feature;
 - the rust-skia prerequisites/cache for `skia`;
 - system libopus for WebRTC voice and the `libremetaverse-opus` adapter;
 - ALSA development headers on Linux, `CoreAudio` on macOS, or WASAPI on Windows

crates/libremetaverse/src/appearance_baker.rs

@@ -150,7 +150,7 @@ impl Baker {
         let texture = crate::assets::AssetTexture::new_with_managed_image(output)?;
         // JPEG2000 is the protocol representation. Keep the decoded image even
         // when a build intentionally excludes that optional codec.
-        #[cfg(feature = "jpeg2000")]
+        #[cfg(any(feature = "jpeg2000", feature = "rust-j2k"))]
         texture.encode()?;
         self.baked_texture = Some(texture);
         Ok(())

crates/libremetaverse/src/asset_models.rs

@@ -9,7 +9,11 @@
 )]
 
 use crate::{Error, Permissions};
+#[cfg(feature = "jpeg2000")]
+use libremetaverse_imaging::J2kCodec as TextureJ2kCodec;
 use libremetaverse_imaging::ManagedImage;
+#[cfg(all(not(feature = "jpeg2000"), feature = "rust-j2k"))]
+use libremetaverse_imaging::RustJ2kCodec as TextureJ2kCodec;
 use libremetaverse_structured_data::{OSD, OSDMap, OSDParser};
 use libremetaverse_types::{AssetType, SaleType, UUID, Vector3, WearableType};
 use std::collections::HashMap;
@@ -526,9 +530,9 @@ impl AssetTexture {
         if self.image.is_some() {
             return Ok(true);
         }
-        #[cfg(feature = "jpeg2000")]
+        #[cfg(any(feature = "jpeg2000", feature = "rust-j2k"))]
         {
-            self.image = Some(libremetaverse_imaging::J2kCodec::decode_bytes(
+            self.image = Some(TextureJ2kCodec::decode_bytes(
                 &self.raw.bytes(),
                 libremetaverse_imaging::J2kDecodeOptions::default(),
             )?);
@@ -543,7 +547,7 @@ impl AssetTexture {
             };
             Ok(true)
         }
-        #[cfg(not(feature = "jpeg2000"))]
+        #[cfg(not(any(feature = "jpeg2000", feature = "rust-j2k")))]
         {
             Err(Error::InvalidOperation)
         }
@@ -570,15 +574,15 @@ impl AssetTexture {
         })
     }
     pub fn decode(&self) -> Result<bool, Error> {
-        #[cfg(feature = "jpeg2000")]
+        #[cfg(any(feature = "jpeg2000", feature = "rust-j2k"))]
         {
-            Ok(libremetaverse_imaging::J2kCodec::decode_bytes(
+            Ok(TextureJ2kCodec::decode_bytes(
                 &self.raw.bytes(),
                 libremetaverse_imaging::J2kDecodeOptions::default(),
             )
             .is_ok())
         }
-        #[cfg(not(feature = "jpeg2000"))]
+        #[cfg(not(any(feature = "jpeg2000", feature = "rust-j2k")))]
         {
             validate_bytes(&self.raw.bytes())?;
             Err(Error::InvalidOperation)
@@ -586,15 +590,15 @@ impl AssetTexture {
     }
     pub fn encode(&self) -> Result<(), Error> {
         let image = self.image.as_ref().ok_or(Error::InvalidOperation)?;
-        #[cfg(feature = "jpeg2000")]
+        #[cfg(any(feature = "jpeg2000", feature = "rust-j2k"))]
         {
-            let encoded = libremetaverse_imaging::J2kCodec::encode(
+            let encoded = TextureJ2kCodec::encode(
                 image,
                 libremetaverse_imaging::J2kEncodeOptions::default(),
             )?;
             self.raw.replace(encoded)
         }
-        #[cfg(not(feature = "jpeg2000"))]
+        #[cfg(not(any(feature = "jpeg2000", feature = "rust-j2k")))]
         {
             let _ = image;
             Err(Error::InvalidOperation)

crates/libremetaverse/src/asset_pipeline_semantics.rs

@@ -1,10 +1,10 @@
-#[cfg(feature = "jpeg2000")]
+#[cfg(any(feature = "jpeg2000", feature = "rust-j2k"))]
 use crate::assets::AssetTexture;
 use crate::assets::{AssetMesh, AssetMutable, AssetSound};
 use crate::{
     AssetCache, AssetCacheComputeAssetCacheFilenameDelegate, Error, GridClient, ImageCodec,
 };
-#[cfg(feature = "jpeg2000")]
+#[cfg(any(feature = "jpeg2000", feature = "rust-j2k"))]
 use libremetaverse_imaging::{ManagedImage, ManagedImageImageChannels};
 use libremetaverse_types::{AssetType, UUID};
 use std::fs;
@@ -58,7 +58,7 @@ fn sound_codec_is_explicitly_feature_gated() {
 }
 
 #[test]
-#[cfg(feature = "jpeg2000")]
+#[cfg(any(feature = "jpeg2000", feature = "rust-j2k"))]
 fn texture_codec_produces_real_valid_payload() {
     let mut image = ManagedImage::new(2, 2, ManagedImageImageChannels::COLOR).unwrap();
     image.red.fill(255);

crates/libremetaverse/src/model_workflow.rs

@@ -11,6 +11,10 @@ use std::path::{Component, Path, PathBuf};
 
 use flate2::{Compression, write::ZlibEncoder};
 use libremetaverse_imaging::ITextureCodec;
+#[cfg(feature = "jpeg2000")]
+use libremetaverse_imaging::J2kCodec as TextureJ2kCodec;
+#[cfg(all(not(feature = "jpeg2000"), feature = "rust-j2k"))]
+use libremetaverse_imaging::RustJ2kCodec as TextureJ2kCodec;
 use libremetaverse_structured_data::{OSD, OSDFormat, OSDParser};
 use libremetaverse_types::compat::{CancellationToken, Uri};
 use libremetaverse_types::{AssetType, Color4, Error, Quaternion, UUID, Vector2, Vector3};
@@ -956,14 +960,14 @@ fn load_texture(
             return Err(Error::InvalidOperation);
         };
         let image = codec.decode(Box::new(std::io::Cursor::new(bytes)))?;
-        #[cfg(feature = "jpeg2000")]
+        #[cfg(any(feature = "jpeg2000", feature = "rust-j2k"))]
         {
-            return libremetaverse_imaging::J2kCodec::encode(
+            return TextureJ2kCodec::encode(
                 &image,
                 libremetaverse_imaging::J2kEncodeOptions::default(),
             );
         }
-        #[cfg(not(feature = "jpeg2000"))]
+        #[cfg(not(any(feature = "jpeg2000", feature = "rust-j2k")))]
         {
             let _ = image;
             return Err(Error::InvalidOperation);