日期: 2019 年 2 月 14 日

macOS Mojave (10.14.3) Android Studio 3.3.1 NDK 19.1.5304403 导入并构建Vuh项目

以前在 Android Studio 3.2.1上vuh库使用的例子 中实现了一个使用 vuh 库的例子。 那个例子中的 vuh 库是我们编译好 libvuh.so 之后直接引用的，我们下面实现通过直接编译代码实现整合。

尝试过使用 ExternalProject_add 跟 include 的方式包含 vuh 库，但是都不是很成功。

其中 ExternalProject_add 导入的项目只能编译一次，即使指定 BUILD_ALWAYS 1 也没用，这个应该是 Ninja 导致的问题，导致当出现多个 ABI 或者 vuh 库代码变动之后，不能重新编译，出现各种编译错误。

使用 include 包含的项目会导致路径信息不正确，无法找到源代码文件。

最后使用 add_subdirectory实现。

修改之后的几个关键文件如下：

注意： VUH_ROOT_DIR 这个变量中指定 vuh 库代码的位置

# For more information about using CMake with Android Studio, read the
# documentation: https://d.android.com/studio/projects/add-native-code.html

# Sets the minimum version of CMake required to build the native library.

cmake_minimum_required(VERSION 3.8)

# for Vulkan
SET(Vulkan_INCLUDE_DIR ${ANDROID_NDK}/sources/third_party/vulkan/src/include/)
SET(Vulkan_LIBRARIES ${ANDROID_NDK}/platforms/${ANDROID_PLATFORM}/arch-${ANDROID_ARCH_NAME}/usr/lib)
if(X86_64)
    SET(Vulkan_LIBRARIES ${Vulkan_LIBRARIES}64)
endif()
SET(Vulkan_LIBRARIES ${Vulkan_LIBRARIES}/libvulkan.so)
add_library(vulkan SHARED IMPORTED)
set_target_properties(vulkan PROPERTIES IMPORTED_LOCATION ${Vulkan_LIBRARIES})

# for vuh
add_definitions(-DVK_USE_PLATFORM_ANDROID_KHR=1 -DVULKAN_HPP_TYPESAFE_CONVERSION=1)
SET(VUH_ROOT_DIR ${CMAKE_CURRENT_SOURCE_DIR}/../../vuh/)
SET(VUH_BUILD_TESTS OFF)
SET(VUH_BUILD_DOCS OFF)
SET(VUH_BUILD_EXAMPLES OFF)

add_subdirectory(${VUH_ROOT_DIR}src/ ${CMAKE_CURRENT_SOURCE_DIR}/build/)

# for example
SET(Vuh_INCLUDE_PATH ${VUH_ROOT_DIR}src/include)
include_directories(${Vulkan_INCLUDE_DIR})
include_directories(${Vuh_INCLUDE_PATH})

# Creates and names a library, sets it as either STATIC
# or SHARED, and provides the relative paths to its source code.
# You can define multiple libraries, and CMake builds them for you.
# Gradle automatically packages shared libraries with your APK.

add_library( # Sets the name of the library.
        native-lib

        # Sets the library as a shared library.
        SHARED

        # Provides a relative path to your source file(s).
        src/main/cpp/native-lib.cpp)


add_dependencies(native-lib vuh)

# Searches for a specified prebuilt library and stores the path as a
# variable. Because CMake includes system libraries in the search path by
# default, you only need to specify the name of the public NDK library
# you want to add. CMake verifies that the library exists before
# completing its build.

find_library( # Sets the name of the path variable.
        log-lib

        # Specifies the name of the NDK library that
        # you want CMake to locate.
        log

        android)

# Specifies libraries CMake should link to your target library. You
# can link multiple libraries, such as libraries you define in this
# build script, prebuilt third-party libraries, or system libraries.

target_link_libraries( # Specifies the target library.
        native-lib

        vulkan

        vuh

        ${log-lib})

注意：由于 vuh 库需要 CMake 3.8 。因此，我们需要手工指定CMake版本为3.10.2 。

如下：

apply plugin: 'com.android.application'

android {
    compileSdkVersion 28
    defaultConfig {
        applicationId "com.mobibrw.vuhandroid"
        minSdkVersion 24
        targetSdkVersion 28
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
        externalNativeBuild {
            cmake {
                version "3.10.2"
                cppFlags "-std=c++14 -v -g"
            }
        }
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
    externalNativeBuild {
        cmake {
            version "3.10.2"
            path "CMakeLists.txt"
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}

如果出现如下错误：

CMake Error: CMake was unable to find a build program corresponding to "Ninja".  CMAKE_MAKE_PROGRAM is not set.  You probably need to select a different build tool.
-- Configuring incomplete, errors occurred!

则执行如下操作：

$ brew install ninja

如果出现如下错误：

* What went wrong:
Execution failed for task ':app:transformNativeLibsWithMergeJniLibsForDebug'.
> More than one file was found with OS independent path 'lib/armeabi-v7a/libvuh.so'

则删除代码中的 jniLibs/armeabi-v7a/libvuh.so 即可解决问题。

完整的例子点击此处下载 vuhAndroid

参考链接