Scaffold core/OBS-adapter split, prove CMake toolchain, add 3-platform CI

First pass on the streamer-tools OBS camera plugin: a minimal but real
CMake project matching the design doc's core-library/OBS-adapter split
(docs/superpowers/specs/2026-09-06-obs-camera-plugin-design.md in the
streamer-tools repo). No LiveKit FFI integration yet -- this proves the
toolchain works.

- core/: dependency-free C++17 library (no OBS dependency), unit tested
  via CTest with no external test framework.
- obs-adapter/: adapted from obsproject/obs-plugintemplate (commit
  3e7d7ac, 2025-12-09). Registers a real, stubbed OBS source type;
  builds as a genuine dynamically-linked OBS module against Ubuntu's
  system libobs-dev (confirmed via ldd/nm, not a fake stand-in).
- Simpler hand-written top-level CMakeLists.txt in place of the
  template's full buildspec-driven bootstrap (which downloads full OBS
  source + prebuilt deps) -- find_package(libobs) alone is enough on
  Linux; falls back to core-library-only when libobs isn't found
  (expected on macOS/Windows CI for now).
- .gitea/workflows/build.yml: 3-platform matrix (ubuntu-latest,
  macos-latest, windows-latest) matching the runners confirmed
  available to this repo under the CyberCoveLLC org.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RL8abRmgFXkVASHkkqiJbE

.gitea/workflows/build.yml

@@ -0,0 +1,72 @@
+name: Build
+
+# Scaffolding CI: proves the CMake toolchain configures and builds on all
+# three platforms the design doc names. It does not yet link livekit-ffi
+# or produce a real OBS-installable package -- see README.md.
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  linux:
+    name: Linux (ubuntu-latest)
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Install build dependencies
+        run: |
+          sudo apt-get update -qq
+          sudo apt-get install -y -qq cmake ninja-build libobs-dev
+
+      - name: Configure
+        run: cmake -S . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release
+
+      - name: Build
+        run: cmake --build build
+
+      - name: Test (core library)
+        run: ctest --test-dir build --output-on-failure
+
+  macos:
+    name: macOS (macos-latest)
+    runs-on: macos-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Install build dependencies
+        run: brew install cmake ninja
+
+      - name: Configure
+        # libobs is not expected to be found here yet (no Homebrew
+        # formula / SDK download wired up in this pass) -- the top-level
+        # CMakeLists.txt falls back to building only the core library in
+        # that case. See README.md.
+        run: cmake -S . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release
+
+      - name: Build
+        run: cmake --build build
+
+      - name: Test (core library)
+        run: ctest --test-dir build --output-on-failure
+
+  windows:
+    name: Windows (windows-latest)
+    runs-on: windows-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Configure
+        # Same story as macOS: no OBS SDK available yet on this runner,
+        # so this proves the core library + MSVC toolchain only.
+        run: cmake -S . -B build -DCMAKE_BUILD_TYPE=Release
+
+      - name: Build
+        run: cmake --build build --config Release
+
+      - name: Test (core library)
+        run: ctest --test-dir build -C Release --output-on-failure

.gitignore

@@ -0,0 +1,2 @@
+build/
+.cache/

CMakeLists.txt

@@ -0,0 +1,36 @@
+cmake_minimum_required(VERSION 3.16)
+
+project(obs-streamer-tools-plugin
+    VERSION 0.0.1
+    DESCRIPTION "OBS Studio source plugin for streamer-tools camera feeds (scaffold, no LiveKit integration yet)"
+    LANGUAGES C CXX
+)
+
+set(CMAKE_C_STANDARD 11)
+set(CMAKE_C_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+enable_testing()
+
+# --- Scaffolding note ------------------------------------------------------
+# This deliberately does NOT use the full obsproject/obs-plugintemplate
+# build system (its cmake/common/bootstrap.cmake + buildspec.json, which
+# download complete OBS source archives and prebuilt dependency bundles
+# for macOS/Windows). That machinery is real and may be worth adopting
+# wholesale in a later phase; for this scaffolding pass the goal is a much
+# simpler CMakeLists.txt that proves out find_package(libobs) plus the
+# core/adapter split on the platform we can actually verify locally
+# (Linux, via the system libobs-dev package). See README.md for the full
+# writeup of what was verified vs. what remains.
+# ----------------------------------------------------------------------------
+
+add_subdirectory(core)
+
+find_package(libobs QUIET)
+if(libobs_FOUND)
+    message(STATUS "libobs found (${libobs_DIR}) -- building OBS adapter module")
+    add_subdirectory(obs-adapter)
+else()
+    message(WARNING "libobs NOT found -- skipping OBS adapter module; core library still builds/tests")
+endif()

LICENSE

@@ -0,0 +1,339 @@
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README.md

@@ -0,0 +1,159 @@
+# obs-streamer-tools-plugin
+
+Native OBS Studio source plugin that will pull streamer-tools camera feeds
+directly from LiveKit over WebRTC (via LiveKit's `livekit-ffi`), replacing
+the current SRT/RTSP-via-VLC-or-Media-Source path for directors. Full
+design: `docs/superpowers/specs/2026-09-06-obs-camera-plugin-design.md` in
+the `streamer-tools` repo (as of this writing, that doc lives on the
+`worktree-obs-plugin-server-api` branch there, not yet merged to `main`).
+
+## Status: scaffolding only
+
+**This repository does not talk to LiveKit or streamer-tools yet.** This
+first pass exists to prove the CMake toolchain, the core-library/OBS-adapter
+split, and the three-platform Gitea Actions CI pipeline all actually work,
+so the next phase (real `livekit-ffi` integration) can be planned against
+verified facts instead of assumptions. See the design doc's "Components"
+and "CI / build pipeline" sections for the target architecture this scaffold
+is standing up.
+
+## Layout
+
+```
+core/           - core library (C++17, no OBS dependency, headless-testable)
+  include/stplugin/
+    core.h        C++ API (ConnectionConfig, core_version())
+    core_c.h       C ABI wrapper the OBS adapter calls into
+  src/core.cpp
+  tests/           dependency-free CTest unit tests
+
+obs-adapter/    - thin OBS glue (C, adapted from obsproject/obs-plugintemplate)
+  src/plugin-main.c       obs_module_load/unload + a stub source registration
+  src/plugin-support.{h,c.in}
+  data/locale/en-US.ini
+
+.gitea/workflows/build.yml   - 3-platform CI matrix (see below)
+```
+
+Everything in `core/` is real, working, unit-tested code -- it just doesn't
+do anything useful yet (a version string, a config struct with non-empty
+validation). Everything in `obs-adapter/` is real OBS module code -- it
+registers an actual `obs_source_info` and builds as a real, dynamically
+loadable OBS module (see "Verified" below) -- but the source is a stub:
+`create`/`destroy` allocate/free a dummy blob, there is no properties UI,
+and no frames are ever pushed. That's the boundary this task was scoped to.
+
+## What's real vs. deliberately deferred
+
+Deferred, per the task that produced this scaffold (out of scope for this
+pass, in scope for the next one):
+
+- No `livekit-ffi` linkage of any kind.
+- No streamer-tools API client (auth, slot-listing, token minting).
+- No properties UI (server URL / room slug / read key / camera dropdown).
+- No frame output (`obs_source_output_video`/`_audio`).
+- No packaging/release step (the design doc's "on a version tag" job).
+
+## Toolchain notes (verified on this machine: Ubuntu 24.04 / Linux)
+
+- **CMake 3.28.3**, **Ninja 1.11.1**, GCC 13.3.0 -- all installed via
+  `apt-get install cmake ninja-build`. Top-level `CMakeLists.txt` requires
+  CMake >= 3.16 (deliberately lower than the official
+  obsproject/obs-plugintemplate's `3.28...3.30` floor -- see below).
+- **OBS plugin template used as reference**: obsproject/obs-plugintemplate,
+  commit `3e7d7ac3b5342cd7d9b88890b9c70b472d1520fc` (2025-12-09, "Fix typo
+  of Visual Studio in README"), fetched fresh from GitHub. `src/plugin-main.c`,
+  `src/plugin-support.{h,c.in}`, and the empty `data/locale/en-US.ini` in
+  `obs-adapter/` are adapted directly from it.
+- **Deliberate deviation from the template's own build system**: the
+  official template's `CMakeLists.txt` chains into
+  `cmake/common/bootstrap.cmake`, which in turn reads `buildspec.json` and
+  *downloads full OBS source archives (pinned to OBS 31.1.1) plus prebuilt
+  dependency bundles* for macOS and Windows. That machinery is real,
+  actively maintained, and probably the right long-term answer for
+  cross-platform reproducible builds -- but it's heavy (multi-hundred-MB
+  downloads, a whole `cmake/{macos,windows,common}` support tree, Qt6,
+  code-signing hooks) and out of scope to stand up and debug in one pass.
+  This scaffold instead uses a much simpler hand-written top-level
+  `CMakeLists.txt` that calls `find_package(libobs)` directly.
+- **On Linux, this actually works far better than expected**: Ubuntu ships
+  a real `libobs-dev` package (`30.0.2+dfsg-3build1` on 24.04, i.e. **not**
+  the 31.1.1 the template's buildspec.json pins -- worth reconciling before
+  the next phase if API surface matters) with genuine CMake package config
+  files (`/usr/lib/x86_64-linux-gnu/cmake/libobs/libobsConfig.cmake`,
+  `libobsTargets.cmake`) that export an `OBS::libobs` imported target --
+  the exact target name the official template expects. `find_package(libobs
+  QUIET)` finds it with zero extra plumbing. This means the OBS adapter in
+  this repo links against **real OBS headers and a real `libobs.so`**, not
+  a stub -- confirmed by `ldd` showing `libobs.so.0` and `nm -D` showing
+  real `obs_module_*` exports (see "Verified" below). Install via
+  `apt-get install libobs-dev` (pulls in Qt6 as a dependency chain, ~seconds
+  on a fast mirror).
+- **macOS/Windows have no equivalent system package** (there's no Homebrew
+  formula or winget package that ships `libobsConfig.cmake` the way Ubuntu's
+  `libobs-dev` does). For those platforms the choices are: (a) adopt the
+  template's full buildspec-driven source/prebuilt-deps download, or (b)
+  find/produce a lighter prebuilt SDK bundle. **This is now a concrete,
+  scoped decision for the next phase**, not a guess -- the CI workflow in
+  this repo currently takes option (c) for this pass only: skip building
+  the OBS adapter on macOS/Windows and build+test just the core library,
+  via the same `find_package(libobs QUIET)` fallback the top-level
+  `CMakeLists.txt` already has for exactly this situation.
+- **`ENABLE_QT`/`ENABLE_FRONTEND_API` template options were not carried
+  over** -- this scaffold's properties-UI-free stub doesn't need Qt yet;
+  the real adapter will need to revisit this once the properties UI
+  (server URL / room slug / read key / camera dropdown) is built.
+
+## What actually builds, and how it was verified
+
+```
+$ cmake -S . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release
+-- libobs found (/usr/lib/x86_64-linux-gnu/cmake/libobs) -- building OBS adapter module
+-- Configuring done
+-- Generating done
+
+$ cmake --build build
+[1/7] Building C object obs-adapter/CMakeFiles/streamer-tools-camera.dir/plugin-support.c.o
+[2/7] Building C object obs-adapter/CMakeFiles/streamer-tools-camera.dir/src/plugin-main.c.o
+[3/7] Building CXX object core/CMakeFiles/stplugin_core.dir/src/core.cpp.o
+[4/7] Linking CXX static library core/libstplugin_core.a
+[5/7] Building CXX object core/tests/CMakeFiles/stplugin_core_tests.dir/test_core.cpp.o
+[6/7] Linking CXX shared module obs-adapter/streamer-tools-camera.so
+[7/7] Linking CXX executable core/tests/stplugin_core_tests
+
+$ ctest --test-dir build --output-on-failure
+1/1 Test #1: stplugin_core_tests ..............   Passed    0.00 sec
+100% tests passed, 0 tests failed out of 1
+
+$ ldd build/obs-adapter/streamer-tools-camera.so | grep obs
+	libobs.so.0 => /lib/x86_64-linux-gnu/libobs.so.0 (...)
+
+$ nm -D build/obs-adapter/streamer-tools-camera.so | grep obs_module
+0000000000001430 T obs_module_free_locale
+0000000000001450 T obs_module_load
+...
+0000000000001490 T obs_module_unload
+```
+
+This is a genuine, dynamically-linked OBS module -- not the "standalone
+shared library without linking OBS" fallback the scaffolding task's scope
+explicitly allowed as an acceptable compromise. That fallback path is still
+exercised (and needed) on macOS/Windows CI for now; see above.
+
+## CI
+
+`.gitea/workflows/build.yml` runs on every push/PR, matrixed across the
+three runners confirmed available to this repo by living under the
+`CyberCoveLLC` org (see the design doc's "CI / build pipeline" section):
+
+| Job | `runs-on` | Runner |
+|---|---|---|
+| `linux` | `ubuntu-latest` | `gitea-runner.internal.cloud-hosting.io` (Global) or `localhost.localdomain` (org-scoped; **note:** now online with `ubuntu-latest`/`ubuntu-24.04`/`ubuntu-22.04` labels -- the design doc recorded it as offline, that's since changed) |
+| `macos` | `macos-latest` | `home-mac` (Global) |
+| `windows` | `windows-latest` | `winvm-builder` (org-scoped to `CyberCoveLLC`) |
+
+The Linux job installs `libobs-dev` and builds the real OBS adapter module
+plus the core library, then runs `ctest`. The macOS/Windows jobs build and
+test only the core library for now (see toolchain notes above for why).
+
+No packaging/release step yet -- out of scope for this pass.

core/CMakeLists.txt

@@ -0,0 +1,20 @@
+# streamer-tools OBS Camera Plugin - core library
+#
+# No OBS dependency by design (see docs/superpowers/specs/
+# 2026-09-06-obs-camera-plugin-design.md in the streamer-tools repo) --
+# this must build and test headlessly on every platform.
+
+add_library(stplugin_core STATIC
+    src/core.cpp
+)
+
+target_include_directories(stplugin_core
+    PUBLIC
+        ${CMAKE_CURRENT_SOURCE_DIR}/include
+)
+
+set_target_properties(stplugin_core PROPERTIES
+    POSITION_INDEPENDENT_CODE ON
+)
+
+add_subdirectory(tests)

core/include/stplugin/core.h

@@ -0,0 +1,57 @@
+/*
+streamer-tools OBS Camera Plugin - core library
+Copyright (C) 2026 CyberCoveLLC <jknapp85@gmail.com>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along
+with this program. If not, see <https://www.gnu.org/licenses/>
+*/
+
+#pragma once
+
+#include <string>
+
+// C++ API for the core library. Per the design doc
+// (docs/superpowers/specs/2026-09-06-obs-camera-plugin-design.md in the
+// streamer-tools repo), this library will eventually own: streamer-tools
+// API auth, LiveKit FFI session management (connect, subscribe, decode,
+// reconnect), and frame callbacks -- all with zero OBS dependency, so it
+// can be built and tested headlessly.
+//
+// THIS IS SCAFFOLDING. Nothing below talks to a real server or to
+// livekit-ffi yet. It exists to prove the core-library/OBS-adapter split
+// builds, links, and is unit-testable, ahead of a later phase that
+// implements the real logic.
+
+namespace stplugin {
+
+// Returns the core library's version string. Placeholder for a real
+// version scheme once the library does something.
+const char *core_version();
+
+// Minimal connection configuration the future core library will use to
+// authenticate against the streamer-tools API
+// (see apps/server/src/rooms/join.routes.ts and
+// apps/server/src/livekit/tokens.ts in the streamer-tools repo for the
+// existing read-key-authed token pattern this will follow) and mint a
+// scoped LiveKit subscriber token. Validation here is intentionally
+// trivial -- it exists to prove the core library is unit-testable
+// headlessly, not to implement the real API client.
+struct ConnectionConfig {
+    std::string server_url;
+    std::string room_slug;
+    std::string read_key;
+
+    bool is_valid() const;
+};
+
+} // namespace stplugin

core/include/stplugin/core_c.h

@@ -0,0 +1,38 @@
+/*
+streamer-tools OBS Camera Plugin - core library
+Copyright (C) 2026 CyberCoveLLC <jknapp85@gmail.com>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along
+with this program. If not, see <https://www.gnu.org/licenses/>
+*/
+
+#pragma once
+
+// Minimal C ABI surface of the core library, for the OBS adapter (plain
+// C, per the obs-plugintemplate convention) to call into the core
+// library (C++) without needing a C++ compiler in that translation unit.
+//
+// This mirrors the boundary the real integration will cross in the
+// other direction: livekit-ffi is a Rust library exposing a C ABI that
+// the C++ core library will link against. Proving a small, deliberate
+// C ABI seam works cleanly here is part of what this scaffold is for.
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+const char *stplugin_core_version(void);
+
+#ifdef __cplusplus
+}
+#endif

core/src/core.cpp

@@ -0,0 +1,36 @@
+/*
+streamer-tools OBS Camera Plugin - core library
+Copyright (C) 2026 CyberCoveLLC <jknapp85@gmail.com>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along
+with this program. If not, see <https://www.gnu.org/licenses/>
+*/
+
+#include "stplugin/core.h"
+#include "stplugin/core_c.h"
+
+namespace stplugin {
+
+const char *core_version() {
+    return "0.0.1-scaffold";
+}
+
+bool ConnectionConfig::is_valid() const {
+    return !server_url.empty() && !room_slug.empty() && !read_key.empty();
+}
+
+} // namespace stplugin
+
+extern "C" const char *stplugin_core_version(void) {
+    return stplugin::core_version();
+}

core/tests/CMakeLists.txt

@@ -0,0 +1,7 @@
+add_executable(stplugin_core_tests
+    test_core.cpp
+)
+
+target_link_libraries(stplugin_core_tests PRIVATE stplugin_core)
+
+add_test(NAME stplugin_core_tests COMMAND stplugin_core_tests)

core/tests/test_core.cpp

@@ -0,0 +1,59 @@
+/*
+streamer-tools OBS Camera Plugin - core library tests
+Copyright (C) 2026 CyberCoveLLC <jknapp85@gmail.com>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along
+with this program. If not, see <https://www.gnu.org/licenses/>
+*/
+
+// Deliberately dependency-free (no gtest/catch2 etc.) so this test target
+// has no network fetch or package-manager step in CI -- proving the
+// "core library builds and tests headlessly, no OBS required" claim
+// without adding another moving part to this scaffolding pass.
+
+#include <cassert>
+#include <cstdio>
+#include <cstring>
+
+#include "stplugin/core.h"
+#include "stplugin/core_c.h"
+
+int main() {
+    // core_version() should return a non-empty string, via both the
+    // C++ API and the C ABI wrapper the OBS adapter will actually call.
+    const char *cpp_version = stplugin::core_version();
+    assert(cpp_version != nullptr);
+    assert(std::strlen(cpp_version) > 0);
+
+    const char *c_version = stplugin_core_version();
+    assert(c_version != nullptr);
+    assert(std::strcmp(cpp_version, c_version) == 0);
+
+    // ConnectionConfig::is_valid() -- trivial non-empty checks, but
+    // exercised through all four combinations to prove the core library
+    // is genuinely testable in isolation.
+    stplugin::ConnectionConfig valid{"https://streamers.example.com", "main-room", "readkey123"};
+    assert(valid.is_valid());
+
+    stplugin::ConnectionConfig missing_url{"", "main-room", "readkey123"};
+    assert(!missing_url.is_valid());
+
+    stplugin::ConnectionConfig missing_slug{"https://streamers.example.com", "", "readkey123"};
+    assert(!missing_slug.is_valid());
+
+    stplugin::ConnectionConfig missing_key{"https://streamers.example.com", "main-room", ""};
+    assert(!missing_key.is_valid());
+
+    std::printf("core: all tests passed\n");
+    return 0;
+}

obs-adapter/CMakeLists.txt

@@ -0,0 +1,37 @@
+# streamer-tools OBS Camera Plugin - OBS adapter
+#
+# Thin glue only, per the design doc: source registration, (eventually)
+# properties UI, and pushing frames into OBS. All real logic lives in
+# ../core. Only added to the build when find_package(libobs) succeeds
+# (see top-level CMakeLists.txt) -- see README.md for why.
+
+set(STPLUGIN_PROJECT_NAME "streamer-tools-camera")
+set(STPLUGIN_PROJECT_VERSION "${PROJECT_VERSION}")
+
+configure_file(
+    src/plugin-support.c.in
+    ${CMAKE_CURRENT_BINARY_DIR}/plugin-support.c
+    @ONLY
+)
+
+add_library(${STPLUGIN_PROJECT_NAME} MODULE
+    src/plugin-main.c
+    ${CMAKE_CURRENT_BINARY_DIR}/plugin-support.c
+)
+
+target_include_directories(${STPLUGIN_PROJECT_NAME}
+    PRIVATE
+        ${CMAKE_CURRENT_SOURCE_DIR}/src
+        ${CMAKE_CURRENT_BINARY_DIR}
+)
+
+target_link_libraries(${STPLUGIN_PROJECT_NAME}
+    PRIVATE
+        OBS::libobs
+        stplugin_core
+)
+
+set_target_properties(${STPLUGIN_PROJECT_NAME} PROPERTIES
+    PREFIX ""
+    OUTPUT_NAME ${STPLUGIN_PROJECT_NAME}
+)

obs-adapter/data/locale/en-US.ini

@@ -0,0 +1,2 @@
+# streamer-tools OBS Camera Plugin - en-US locale
+# No user-facing strings yet -- this is scaffolding (see plugin-main.c).

obs-adapter/src/plugin-main.c

@@ -0,0 +1,74 @@
+/*
+streamer-tools OBS Camera Plugin
+Copyright (C) 2026 CyberCoveLLC <jknapp85@gmail.com>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along
+with this program. If not, see <https://www.gnu.org/licenses/>
+*/
+
+/* SCAFFOLDING. This registers a source type so the OBS-adapter/core-
+ * library split and OBS's module-loading toolchain can be proven end to
+ * end, but it does not do anything real yet: no LiveKit FFI session, no
+ * frames pushed via obs_source_output_video/audio, no properties UI.
+ * See docs/superpowers/specs/2026-09-06-obs-camera-plugin-design.md in
+ * the streamer-tools repo for what this becomes. */
+
+#include <obs-module.h>
+#include <util/bmem.h>
+#include <plugin-support.h>
+#include <stplugin/core_c.h>
+
+OBS_DECLARE_MODULE()
+OBS_MODULE_USE_DEFAULT_LOCALE(PLUGIN_NAME, "en-US")
+
+static const char *stcam_source_get_name(void *unused)
+{
+	UNUSED_PARAMETER(unused);
+	return "streamer-tools Camera (scaffold - not yet functional)";
+}
+
+static void *stcam_source_create(obs_data_t *settings, obs_source_t *source)
+{
+	UNUSED_PARAMETER(settings);
+	UNUSED_PARAMETER(source);
+	/* No LiveKit session, no state to speak of yet -- just proving the
+	 * source registers and OBS can instantiate/destroy it cleanly. */
+	return bzalloc(1);
+}
+
+static void stcam_source_destroy(void *data)
+{
+	bfree(data);
+}
+
+static struct obs_source_info streamer_tools_camera_source = {
+	.id = "streamer_tools_camera_source",
+	.type = OBS_SOURCE_TYPE_INPUT,
+	.output_flags = OBS_SOURCE_ASYNC_VIDEO,
+	.get_name = stcam_source_get_name,
+	.create = stcam_source_create,
+	.destroy = stcam_source_destroy,
+};
+
+bool obs_module_load(void)
+{
+	obs_log(LOG_INFO, "streamer-tools camera plugin scaffold loaded (core library version %s)",
+		stplugin_core_version());
+	obs_register_source(&streamer_tools_camera_source);
+	return true;
+}
+
+void obs_module_unload(void)
+{
+	obs_log(LOG_INFO, "streamer-tools camera plugin scaffold unloaded");
+}

obs-adapter/src/plugin-support.c.in

@@ -0,0 +1,43 @@
+/*
+streamer-tools OBS Camera Plugin
+Copyright (C) 2026 CyberCoveLLC <jknapp85@gmail.com>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along
+with this program. If not, see <https://www.gnu.org/licenses/>
+*/
+
+/* Adapted from obsproject/obs-plugintemplate (commit 3e7d7ac,
+ * 2025-12-09), the standard starting point for third-party OBS
+ * plugins. */
+
+#include "plugin-support.h"
+
+const char *PLUGIN_NAME = "@STPLUGIN_PROJECT_NAME@";
+const char *PLUGIN_VERSION = "@STPLUGIN_PROJECT_VERSION@";
+
+void obs_log(int log_level, const char *format, ...)
+{
+	size_t length = 4 + strlen(PLUGIN_NAME) + strlen(format);
+
+	char *template = malloc(length + 1);
+
+	snprintf(template, length, "[%s] %s", PLUGIN_NAME, format);
+
+	va_list(args);
+
+	va_start(args, format);
+	blogva(log_level, template, args);
+	va_end(args);
+
+	free(template);
+}

obs-adapter/src/plugin-support.h

@@ -0,0 +1,42 @@
+/*
+streamer-tools OBS Camera Plugin
+Copyright (C) 2026 CyberCoveLLC <jknapp85@gmail.com>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along
+with this program. If not, see <https://www.gnu.org/licenses/>
+*/
+
+/* Adapted from obsproject/obs-plugintemplate (commit 3e7d7ac,
+ * 2025-12-09), the standard starting point for third-party OBS
+ * plugins. */
+
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+
+extern const char *PLUGIN_NAME;
+extern const char *PLUGIN_VERSION;
+
+void obs_log(int log_level, const char *format, ...);
+extern void blogva(int log_level, const char *format, va_list args);
+
+#ifdef __cplusplus
+}
+#endif