配置 ARCore 会话，为您的应用打造 AR 体验。
什么是会话？
所有 AR 进程（例如动作跟踪、环境理解和光照估测）都发生在 ARCore 会话内。ArSession 是 ARCore API 的主入口点。它管理 AR 系统状态并处理会话生命周期，允许应用创建、配置、启动或停止会话。最重要的是，它使应用能够接收允许访问相机图片和设备姿势的帧。
会话可用于配置以下功能：
验证 ARCore 是否已安装且是最新版本
在创建 ArSession 之前，请验证 ARCore 是否已安装且是最新版本。如果未安装 ARCore，会话创建将失败，并且后续安装或升级 ARCore 都需要重启应用。
/*
* Check if ARCore is currently usable, i.e. whether ARCore is supported and
* up to date.
*/
int32_t is_arcore_supported_and_up_to_date(void* env, void* context) {
ArAvailability availability;
ArCoreApk_checkAvailability(env, context, &availability);
switch (availability) {
case AR_AVAILABILITY_SUPPORTED_INSTALLED:
return true;
case AR_AVAILABILITY_SUPPORTED_APK_TOO_OLD:
case AR_AVAILABILITY_SUPPORTED_NOT_INSTALLED: {
ArInstallStatus install_status;
// ArCoreApk_requestInstall is processed asynchronously.
CHECK(ArCoreApk_requestInstall(env, context, true, &install_status) ==
AR_SUCCESS);
return false;
}
case AR_AVAILABILITY_UNSUPPORTED_DEVICE_NOT_CAPABLE:
// This device is not supported for AR.
return false;
case AR_AVAILABILITY_UNKNOWN_CHECKING:
// ARCore is checking the availability with a remote query.
// This function should be called again after waiting 200 ms
// to determine the query result.
handle_check_later();
return false;
case AR_AVAILABILITY_UNKNOWN_ERROR:
case AR_AVAILABILITY_UNKNOWN_TIMED_OUT:
// There was an error checking for AR availability.
// This may be due to the device being offline.
// Handle the error appropriately.
handle_unknown_error();
return false;
default: // All enum cases have been handled.
return false;
}
}
创建会话
在 ARCore 中创建和配置会话。
// Create a new ARCore session. ArSession* ar_session = NULL; CHECK(ArSession_create(env, context, &ar_session) == AR_SUCCESS); // Create a session config. ArConfig* ar_config = NULL; ArConfig_create(ar_session, &ar_config); // Do feature-specific operations here, such as enabling depth or turning on // support for Augmented Faces. // Configure the session. CHECK(ArSession_configure(ar_session, ar_config) == AR_SUCCESS);
关闭会话
ArSession 拥有大量原生堆内存。未明确关闭会话可能会导致应用耗尽原生内存并崩溃。当不再需要 AR 会话时，调用 ArSession_destroy() 以释放资源。
// Release memory used by the AR session. ArSession_destroy(session);