Implementation:Tencent Ncnn CMake Vulkan Enable

Knowledge Sources	ncnn
Domains	GPU_Computing, Build_System
Last Updated	2026-02-09 00:00 GMT

Overview

External tool documentation for enabling Vulkan GPU compute in the ncnn CMake build system.

Description

This is an External Tool Doc documenting the CMake configuration required to build ncnn with Vulkan support. The primary option is NCNN_VULKAN=ON in the root CMakeLists.txt. This triggers:

• Detection of Vulkan SDK or fallback to the built-in simplevk loader
• Compilation of GLSL compute shaders to SPIR-V via bundled glslang
• Inclusion of Vulkan-specific source files (gpu.cpp, command.cpp, pipeline.cpp, etc.)
• Linking against the Vulkan driver library

The NCNN_SIMPLEVK option (enabled by default when Vulkan SDK is not found) uses ncnn's built-in Vulkan function loader, eliminating the Vulkan SDK dependency for deployment.

Usage

Pass -DNCNN_VULKAN=ON when configuring ncnn with CMake. The build system handles Vulkan SDK detection, shader compilation, and linking automatically.

Code Reference

Source Location

• Repository: ncnn
• File: CMakeLists.txt (root), src/CMakeLists.txt (library build)
• Lines: CMakeLists.txt:L1-892 (root with NCNN_VULKAN option), src/CMakeLists.txt:L1-806 (Vulkan shader compilation)

Signature

# Basic Vulkan build
mkdir build && cd build
cmake -DNCNN_VULKAN=ON ..
make -j$(nproc)

# With explicit Vulkan SDK path
cmake -DNCNN_VULKAN=ON \
      -DVulkan_INCLUDE_DIR=/path/to/vulkan/include \
      -DVulkan_LIBRARY=/path/to/libvulkan.so \
      ..

# Using built-in simplevk loader (no SDK needed)
cmake -DNCNN_VULKAN=ON -DNCNN_SIMPLEVK=ON ..

Import

# CMake — no code import needed
# The NCNN_VULKAN preprocessor macro is defined automatically

I/O Contract

Inputs

Name	Type	Required	Description
NCNN_VULKAN	CMake BOOL	Yes	ON to enable Vulkan GPU compute
Vulkan_INCLUDE_DIR	CMake PATH	No	Vulkan SDK headers (auto-detected)
Vulkan_LIBRARY	CMake PATH	No	Vulkan driver library (auto-detected)
NCNN_SIMPLEVK	CMake BOOL	No	Use built-in Vulkan loader (auto-enabled)

Outputs

Name	Type	Description
libncnn.a / libncnn.so	Library	ncnn library with Vulkan compute support
SPIR-V shaders	Embedded	Compiled GPU shaders embedded in the library

Usage Examples

Linux Desktop Build

git clone https://github.com/Tencent/ncnn.git
cd ncnn
mkdir build && cd build

cmake -DNCNN_VULKAN=ON \
      -DCMAKE_BUILD_TYPE=Release \
      ..
make -j$(nproc)

Android Cross-Compilation

cmake -DCMAKE_TOOLCHAIN_FILE=$NDK/build/cmake/android.toolchain.cmake \
      -DANDROID_ABI=arm64-v8a \
      -DANDROID_PLATFORM=android-24 \
      -DNCNN_VULKAN=ON \
      ..
make -j$(nproc)

Related Pages

Implements Principle

• Principle:Tencent_Ncnn_Vulkan_Build_Configuration

Requires Environment

• Environment:Tencent_Ncnn_Vulkan_Environment