SDK changes for submodule

README.md

@@ -35,32 +35,69 @@ Native app internals are grouped by boundary:
 - CMake 3.24 or newer.
 - Node.js and npm for the control UI.
 - Blackmagic Desktop Video drivers and a DeckLink device for the current production video I/O backend.
-- NDI 6 SDK for NDI input/output builds.
-- Slang binary release with `slangc.exe`, `slang-compiler.dll`, `slang-glslang.dll`, and `LICENSE`.
-- `msdf-atlas-gen` Windows binary release with `msdf-atlas-gen.exe`, `LICENSE.txt`, and any adjacent runtime DLLs for font atlas generation.
+- Blackmagic DeckLink SDK 16.0 for DeckLink SDK reference files and redistribution notices.
+- NDI 6 SDK for NDI input/output builds. CMake expects `Include/`, `Lib/x64/Processing.NDI.Lib.x64.lib`, `Bin/x64/Processing.NDI.Lib.x64.dll`, and the NDI license/notice files.
+- Slang 2026.8 Windows x86_64 binary release with `bin/slangc.exe`, `bin/slang-compiler.dll`, `bin/slang-glslang.dll`, and `LICENSE`.
+- `msdf-atlas-gen` Windows binary release with `msdf-atlas-gen.exe`, `LICENSE.txt`, `README.md`, and any adjacent runtime DLLs for font atlas generation.
 
-Default expected Slang path:
+### Third-party SDK bundle
+
+Org members can initialize the private SDK bundle submodule:
+
+```powershell
+git submodule update --init --recursive
+```
+
+When present, CMake defaults to this private bundle:
+
+```text
+video-io-3rdParty/
+  Blackmagic DeckLink SDK 16.0/
+  NDI 6 SDK/
+  slang-2026.8-windows-x86_64/
+  msdf-atlas-gen/
+```
+
+The parent repository is public, but this bundle is private. External builders need to obtain the SDKs from their vendors and place them in an ignored local `3rdParty/` folder with the same layout, or pass explicit CMake paths.
+
+Fallback local Slang path:
 
 ```text
 3rdParty/slang-2026.8-windows-x86_64
 ```
 
-Default expected `msdf-atlas-gen` path:
+Fallback local `msdf-atlas-gen` path:
 
 ```text
 3rdParty/msdf-atlas-gen
 ```
 
-Default expected NDI SDK path:
+Fallback local NDI SDK path:
 
 ```text
 3rdParty/NDI 6 SDK
 ```
 
-Override example:
+Fallback local Blackmagic DeckLink SDK path:
+
+```text
+3rdParty/Blackmagic DeckLink SDK 16.0
+```
+
+Single-root override example:
 
 ```powershell
-cmake --preset vs2022-x64-debug -DSLANG_ROOT="D:/SDKs/slang-2026.8-windows-x86_64"
+cmake --preset vs2022-x64-debug -DTHIRD_PARTY_ROOT="D:/SDKs/video-io-3rdParty"
+```
+
+Individual override example:
+
+```powershell
+cmake --preset vs2022-x64-debug `
+  -DSLANG_ROOT="D:/SDKs/slang-2026.8-windows-x86_64" `
+  -DMSDF_ATLAS_GEN_ROOT="D:/SDKs/msdf-atlas-gen" `
+  -DNDI_SDK_ROOT="D:/SDKs/NDI 6 SDK" `
+  -DDECKLINK_SDK_ROOT="D:/SDKs/Blackmagic DeckLink SDK 16.0"
 ```
 
 ## Build
@@ -289,8 +326,11 @@ The Gitea workflow expects two act runners:
 
 The Windows jobs validate native third-party dependencies before configuring CMake. Because `3rdParty/` is ignored, configure this path on the runner or in a Gitea repository variable:
 
+- `THIRD_PARTY_ROOT`: path to a bundle containing the expected SDK folder layout.
 - `SLANG_ROOT`: path to the Slang binary release folder containing `bin/slangc.exe`.
 - `MSDF_ATLAS_GEN_ROOT`: path to the `msdf-atlas-gen` binary release folder containing `msdf-atlas-gen.exe`.
+- `NDI_SDK_ROOT`: path to the NDI SDK folder containing `Include/`, `Lib/x64/`, and `Bin/x64/`.
+- `DECKLINK_SDK_ROOT`: path to the Blackmagic DeckLink SDK folder containing `Win/include/DeckLinkAPI.idl`.
 
 The Windows runner also needs the Visual Studio ATL component installed. In Visual Studio Build Tools 2022, add `C++ ATL for latest v143 build tools (x86 & x64)`, component ID `Microsoft.VisualStudio.Component.VC.ATL`.
 
@@ -299,9 +339,11 @@ Example runner paths:
 ```text
 D:\SDKs\slang-2026.8-windows-x86_64
 D:\SDKs\msdf-atlas-gen
+D:\SDKs\NDI 6 SDK
+D:\SDKs\Blackmagic DeckLink SDK 16.0
 ```
 
-If `SLANG_ROOT` or `MSDF_ATLAS_GEN_ROOT` is not set, the workflow falls back to the repo-local defaults under `3rdParty/`.
+If these variables are not set, CMake first looks under the private `video-io-3rdParty/` submodule and then falls back to repo-local defaults under ignored `3rdParty/`.
 
 ## Still Todo
 
@@ -380,4 +422,4 @@ Add a section to shaders/SHADER_CONTRACT.md with:
 manifest example
 custom element lifecycle
 available properties/functions
-rule: all controls must map to declared parameters
+rule: all controls must map to declared parameters