Technical

Licences and notices

Block Viewer is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License, version 3 or (at your option) any later version (see LICENSE and LICENSE.md).

Block Viewer is a hobby fork built on the open-source Block Viewer codebase. It is not an official Aurora release, is not affiliated with the Block Viewer project, and is not positioned as a competitor to it.

Block Viewer is not provided, endorsed or supported by Linden Research, Inc. (“Linden Lab”) or The Phoenix Firestorm Project, Inc. Second Life® is a trademark of Linden Research, Inc.

Code derived from the Second Life viewer and Firestorm

Many parts of this program are Rust ports of the Second Life viewer (Copyright © Linden Research, Inc.) and of the Firestorm viewer (Copyright © The Phoenix Firestorm Project, Inc.), both distributed under the GNU Lesser General Public License, version 2.1. Each ported file says which original sources it follows (“originally LGPL 2.1”).

As permitted by section 3 of the LGPL 2.1, the copy of that code included in this program is distributed under the GNU General Public License, version 3 or any later version. The original code remains available under the LGPL 2.1 from its authors:

Second Life viewer — https://github.com/secondlife/viewer
Firestorm — https://github.com/FirestormViewer/phoenix-firestorm

The Second Life message template (crates/block-msg/message_template.msg) and the avatar definition files (crates/block-viewer/assets/character/) come from the Second Life viewer sources (originally LGPL 2.1). The character/bake/ subdirectory contains the same sources’ TGA skin, clothing and visibility masks, used by the local wearable preview. The Blender extension bundles the same avatar_skeleton.xml and retains its provenance in blender/block_live/SKELETON-NOTICE.txt.

The terrain alpha ramp (crates/block-render/src/terrain_alpha_ramp.r8) is the decoded 256-square linear grayscale image from the Legacy Viewer’s indra/newview/skins/default/textures/alpha_gradient_2d.j2c (source revision 003e22b6), Copyright Linden Research, Inc., originally LGPL 2.1 and distributed here under GPL-3.0-or-later as described above. Rows are retained top-down.

The RLVa command parser, restriction rules, inventory conventions and camera behaviors in crates/block-viewer/src/world/rlva/ and world/rlva.rs follow the Legacy Viewer’s indra/newview/rlv*.cpp and rlv*.h: Copyright © 2009-2020 Kitty Barnett, originally LGPL 2.1, distributed here under GPL-3.0-or-later as described above.

Bundled assets

Asset	Location	License
Tabler Icons — Copyright © 2020-2026 Paweł Kuna	`assets/tabler-icons/`, `crates/block-viewer/assets/icons/tabler/`	MIT (LICENSE)
Inter typeface, Regular and SemiBold, version 4.001	`crates/block-viewer/assets/fonts/`	SIL Open Font License 1.1 (LICENSE-Inter.txt)
Noto Sans, Regular and SemiBold, version 2.015 (notofonts/latin-greek-cyrillic, hinted)	`crates/block-viewer/assets/fonts/`	SIL Open Font License 1.1 (LICENSE-NotoSans.txt)
Roboto, Regular and Medium, version 3.011 (googlefonts/roboto-3-classic, hinted)	`crates/block-viewer/assets/fonts/`	SIL Open Font License 1.1 (LICENSE-Roboto.txt)
OpenDyslexic, Regular and Bold, version 0.910.12 — Copyright 2012-2019 Abbie Gonzalez, Reserved Font Name OpenDyslexic (antijingoist/opendyslexic, release `v0.91.12`, unmodified)	`crates/block-viewer/assets/fonts/`	SIL Open Font License 1.1 (LICENSE-OpenDyslexic.txt)
Noto Color Emoji font, version 2.057 — Copyright 2022 Google Inc. (googlefonts/noto-emoji, tag `v2026-09-24-unicode18_0`, built into the executable)	`assets/emoji/`	SIL Open Font License 1.1 (LICENSE-OFL.txt)
MIT KEMAR HRTF measurements, diffuse-field equalized set — Copyright 1994 MIT Media Laboratory, by Bill Gardner and Keith Martin (https://sound.media.mit.edu/resources/KEMAR.html: “provided free with no restrictions on use, provided the authors are cited”); turned into minimum-phase filters by `scripts/generate-hrtf.py` (built into the executable; origin, citation and changes in README.md)	`assets/hrtf/kemar.bin`	Free use with credit to the authors (their terms, quoted in the README)
HYG star database v4.4 — David Nash (astronexus, https://codeberg.org/astronexus/hyg); the stars of magnitude 6.5 and brighter, rounded to fixed point by `scripts/generate-star-catalog.py` (built into the executable; origin and changes in README.md)	`assets/stars/stars.bin`	CC BY-SA 4.0 (LICENSE-HYG.md); the derived table is shared under the same licence
Block mark / app icon	`assets/branding/`	Block brand assets (see sibling Block injector repo)
Upstream viewer codebase	whole tree	Derived from Block Viewer (GPL-3.0-or-later); product branding here is independent
Photo filters of the Second Life viewer `indra/newview/app_settings/filters` (the 30 XML files unchanged, from the Legacy Viewer’s sources at commit `8ffe7065`), made by Linden Lab	`crates/block-render/src/looks/legacy/` (built into the executable)	Originally LGPL 2.1, distributed here under GPL-3.0-or-later as described above
LSL keyword names, signatures and help from Firestorm `indra/newview/app_settings/keywords_lsl_default.xml`	`crates/block-viewer/assets/lsl/keywords.json`, `reference.json`	Originally LGPL 2.1, distributed here under GPL-3.0-or-later as described above
Windlight presets of Firestorm `indra/newview/app_settings/windlight` (`days`, `skies`, `water`; XML files unchanged, commit `c33bfee2`), made by Linden Lab and by Second Life residents for the Phoenix / Firestorm viewers (their names and tags are in the preset names); the files carry no notice of their own and are distributed in the Firestorm sources under its LGPL 2.1 (`LICENSE`, `doc/LICENSE-source.txt`)	`crates/block-viewer/assets/windlight/windlight.zip` (built into the executable)	Originally LGPL 2.1, distributed here under GPL-3.0-or-later as described above
Hunspell spelling dictionaries of ten languages (wooorm/dictionaries, commit `8cfea406`, unchanged; built into the executable, the list and the origin of each in README.md)	`crates/block-viewer/assets/dictionaries/`	Their own licences, each next to its dictionary (`LICENSE.txt`) and shipped in `assets/dictionaries/`: MIT AND BSD (English), MPL-2.0 (French), GPL-2.0 OR GPL-3.0 (German), GPL-3.0 OR LGPL-3.0 OR MPL-1.1 (Spanish), GPL-3.0 OR LGPL-3.0 OR MPL-2.0 (Polish), LGPL-3.0 OR MPL-2.0 (Portuguese), BSD-3-Clause (Russian), GPL-2.0 OR LGPL-2.1 OR MPL-1.1 (Danish)
Second Life glossary of the Legacy Viewer’s dictionaries (`sl.dic`) and its auto-replace lists (`indra/newview/app_settings/autoreplace.xml`, unchanged)	`crates/block-viewer/assets/dictionaries/sl/`, `crates/block-viewer/assets/autoreplace.xml`	Originally LGPL 2.1, distributed here under GPL-3.0-or-later as described above
LSL preprocessor rules from Modular Systems / Firestorm `indra/newview/fslslpreproc.cpp`	`crates/block-viewer/src/ui/scripts/preprocessor/`	BSD-3-Clause (notice), retained alongside this GPL-3.0-or-later adaptation
Colour and dithering code of egui-wgpu’s `egui.wgsl` — Copyright © Emil Ernerfeldt and the egui contributors	`crates/block-render/src/shaders/labels.wgsl`	MIT OR Apache-2.0, retained alongside this GPL-3.0-or-later adaptation
Screen space shadows of Bend Studio (`bend_sss_gpu.h`, `bend_sss_cpu.h`, as shipped in Days Gone) — Copyright © 2023 Sony Interactive Entertainment, ported to WGSL and Rust	`crates/block-render/src/shaders/contact_shadows.wgsl`, `crates/block-render/src/contact_shadows.rs`	Apache-2.0, notice retained at the top of `contact_shadows.wgsl`
Ground-truth ambient occlusion of Intel’s XeGTAO (`XeGTAO.hlsli`, `vaGTAO.hlsl`, GameTechDev/XeGTAO), with its bent normals — Copyright © 2016-2021 Intel Corporation, ported to WGSL	`crates/block-render/src/shaders/gtao.wgsl`, `crates/block-render/src/gtao.rs`	MIT, notice retained at the top of `gtao.wgsl`
Spherical caps’ intersection and cone specular occlusion of Google’s Filament (`sphericalCapsIntersection`, `specularAO_Cones`, google/filament) — Copyright © 2018 The Android Open Source Project, rewritten in WGSL	`crates/block-render/src/shaders/common.wgsl` (`spherical_caps_intersection`, `cone_specular_occlusion`)	Apache-2.0, retained alongside this GPL-3.0-or-later adaptation

Fonts keep their own license (the OFL allows bundling them with software under any license). The license texts of the fonts are next to them.

Media plugins

Web pages and video on media faces go through a separate pack, built by the “Media plugins” workflow (.github/workflows/media-plugins.yml) and published as the GitHub releases media-plugins-<n>. The viewer downloads it when media need it and installs it in the user’s data folder. Each release attaches the license texts (LICENSES\ in the archive) and the corresponding source of the Linden Lab code. On Linux, video plays through the system’s GStreamer, which the pack does not include.

Component	License
`SLPlugin.exe`, `media_plugin_cef.dll`, `media_plugin_libvlc.dll` (Windows), `SLPlugin`, `libmedia_plugin_cef.so`, `libmedia_plugin_gstreamer.so` (Linux), built unmodified from a pinned commit of the Firestorm sources	LGPL 2.1 (the commit is named in the pack’s `block-media-plugins.json` and in the release notes)
Chromium Embedded Framework, Dullahan (Linden Lab’s prebuilt package)	BSD-3-Clause and the licenses of Chromium’s third-party code
LibVLC and its modules (Linden Lab’s prebuilt package of VLC 3.0)	LGPL 2.1 or later; some modules GPL 2 or later
Microsoft Visual C++ runtime (`msvcp140.dll`, `vcruntime140*.dll`)	Redistributable under the Visual Studio license terms

Rust dependencies

The crates used by Block Viewer (see Cargo.lock) are under licenses compatible with the GPL version 3 (mostly MIT and/or Apache-2.0).

HIDAPI

The MIT-licensed hidapi Rust crate bundles native HIDAPI for SpaceMouse input. That native code is distributed here under its BSD-style license option. Source: https://github.com/libusb/hidapi (vendored by the crate version recorded in Cargo.lock).

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright notice,
  this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
  notice, this list of conditions and the following disclaimer in the
  documentation and/or other materials provided with the distribution.
* Neither the name of Signal 11 Software nor the names of its
  contributors may be used to endorse or promote products derived from
  this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS “AS IS” AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

V-HACD

The unmodified V-HACD 4.1 header in crates/block-assets/native/vhacd/ is distributed under BSD-3-Clause. Its source revision and checksum are recorded alongside it. The following notice also applies to its compiled code included in Block Viewer:

BSD 3-Clause License

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

Sonora audio processing

Sonora 0.2 and its sonora-* components provide the pure Rust WebRTC audio processing pipeline (AEC3, noise suppression, AGC2 and high-pass filtering). Source: https://github.com/dignifiedquire/sonora (BSD-3-Clause).

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
Neither the name of Google nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.