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将模型直接导入内存

将模型直接导入内存

警告

本文介绍的功能在 Community SDK 版本中不可用。
您应该升级到 Engineering / Sim SDK版本才能使用它。

章节:

UNIGINE的 Import System允许您以各种外部格式(FBX, DAE, OBJ等)导入模型和场景。默认情况下(即当使用DefaultProcessor时)，对于每个导入的场景或模型，都会在磁盘上创建一组UNIGINE文件格式的对应文件(.mesh, .dds, .node,等)。

然而，在某些情况下，可能需要直接将模型导入到当前场景中，而不需要在磁盘上创建任何不必要的文件(例如，为智能城市应用程序加载建筑物模型等)。此外，由于减少了缓慢的磁盘I/O操作，这种方法可以加快整个导入过程。

为此，我们应该创建一个自定义的导入处理器。

这个例子演示了如何:

为FbxImporter插件创建自己的自定义导入处理器。
使用您的自定义导入处理器将存储在FBX文件中的场景带到当前加载的UNIGINE场景。

注意

建议阅读 Import System文章，并熟悉基本导入功能类。

在我们开始之前，先讲一点理论(作为重点)：

UNIGINE API为我们提供了一组的类，用于实现自定义模型导入。
关于导入场景的所有元信息都应该存储在ImportScene类的一个实例中。基本上，场景可能包含网格(ImportMesh)、灯光(ImportLight)、摄像机(ImportCamera)和其他元素(参见完整列表 here).
自定义导入处理器应该从ImportProcessor类继承。

Creating a Custom Import Processor创建自定义导入处理器#

让我们从处理器开始。我们称它为MemoryProcessor，并实现在当前UNIGINE世界中从fbx文件的内容创建对象，跳过不必要的数据保存到磁盘。因此，我们将简单地运行导入的FBX场景的组件(摄像机、灯光和网格)，构建相应的节点层次结构，添加到世界中，并创建所有必要的材质和纹理。下面的代码补充了解释该过程基本方面的注释。

Direct Memory Import Processor

源代码 (C++)

// including necessary libraries
#include <UnigineImport.h>
#include <UnigineMaterials.h>
#include <UnigineMeshStatic.h>

using namespace Unigine;
// our custom ImportProcessor to be used for direct memory import of scenes
class MemoryProcessor : public ImportProcessor
{
public:

	void convertNode(const NodePtr &node_parent, const ImportNodePtr &import_node_parent,
		NodePtr &node, const ImportNodePtr &import_node)
	{
		using namespace Unigine::Math;
		if (ImportCameraPtr import_camera = import_node->getCamera())
		{
			node = getImporter()->importCamera(getImportProcessor(), import_camera);
			if (node)
				node->setWorldTransform(Mat4(import_node->getTransform()));
		} else if (ImportLightPtr import_light = import_node->getLight())
		{
			node = getImporter()->importLight(getImportProcessor(), import_light);
			if (node)
				node->setWorldTransform(Mat4(import_node->getTransform()));
		} else if (ImportMeshPtr import_mesh = import_node->getMesh())
		{
			ObjectPtr object;
			if (import_mesh->isHasAnimations())
			{
				float fps = getImporter()->getParameterFloat("fps");
				auto mesh_skinned = ObjectMeshSkinned::create(meshes[import_mesh->getFilepath()]);
				if (MeshPtr animation = meshes_animations.value(import_mesh->getFilepath()))
				{
					int animation_id = mesh_skinned->addAnimation(animation);
					mesh_skinned->setNumLayers(1);
					mesh_skinned->setAnimation(0, animation_id);
				}
				mesh_skinned->setSpeed(fps);
				object = mesh_skinned;
			} else
			{
				auto mesh_static = ObjectMeshStatic::create();
				mesh_static->setMeshProceduralMode(true);
				mesh_static->applyMeshProcedural(meshes[import_mesh->getFilepath()]);

				object = mesh_static;
				object->setWorldTransform(Mat4(import_node->getTransform()));
			}

			int num_geometries = import_mesh->getNumGeometries();
			for (int i = 0; i < num_geometries; ++i)
			{
				ImportGeometryPtr geometry = import_mesh->getGeometry(i);
				int num_surfaces = geometry->getNumSurfaces();
				for (int s = 0; s < num_surfaces; ++s)
				{
					ImportSurfacePtr surface = geometry->getSurface(s);
					const int surface_index = surface->getTargetSurface();
					if (surface_index == -1 || surface_index >= object->getNumSurfaces())
					{
						Log::error("MemoryProcessor: can't find surface \"%s\".\n", surface->getName());
						continue;
					}

					if (!compare(surface->getMinVisibleDistance(), -Consts::INF))
					{
						object->setMinVisibleDistance(surface->getMinVisibleDistance(),
							surface_index);
					}
					if (!compare(surface->getMaxVisibleDistance(), Consts::INF))
					{
						object->setMaxVisibleDistance(surface->getMaxVisibleDistance(),
							surface_index);
					}

					object->setMinFadeDistance(surface->getMinFadeDistance(), surface_index);
					object->setMaxFadeDistance(surface->getMaxFadeDistance(), surface_index);

					if (ImportMaterialPtr import_material = surface->getMaterial())
					{
						object->setMaterial(materials[import_material->getFilepath()],
							surface_index);
					}
				}
			}

			node = object;
		} else
		{
			node = NodeDummy::create();
			node->setWorldTransform(Mat4(import_node->getTransform()));
		}

		node->setName(import_node->getName());

		getImporter()->importNodeChild(getImportProcessor(), node_parent, import_node_parent,
			node, import_node);

		int num_children = import_node->getNumChildren();
		for (int i = 0; i < num_children; ++i)
		{
			NodePtr child;
			convertNode(node, import_node, child, import_node->getChild(i));
			node->addWorldChild(child);
		}
	}

protected:
	// method to be called on mesh processing
	bool onProcessMesh(const MeshPtr &mesh, const ImportMeshPtr &import_mesh) override
	{
		UGUID guid = generate_unique_guid();
		import_mesh->setFilepath(guid.getString());
		meshes.append(import_mesh->getFilepath(), mesh);
		return true;
	}

	// method to be called on mesh animation processing
	bool onProcessAnimation(const MeshPtr &animation, const ImportMeshPtr &import_mesh,
		const ImportAnimationPtr &import_animation) override
	{
		meshes_animations.append(import_mesh->getFilepath(), animation);
		return true;
	}

	// method to be called on texture processing
	bool onProcessTexture(const ImportTexturePtr &import_texture) override
	{
		import_texture->setFilepath(import_texture->getOriginalFilepath());
		return true;
	}

	// method to be called on material processing
	bool onProcessMaterial(const MaterialPtr &material,
		const ImportMaterialPtr &import_material) override
	{
		UGUID guid = generate_unique_guid();
		import_material->setFilepath(guid.getString());
		materials.append(guid.getString(), material);
		return true;
	}

private:
	UGUID generate_unique_guid()
	{
		UGUID guid;
		guid.generate();

		int attempt = 100;
		while(guids.contains(guid) && attempt-- > 0)
			guid.generate();

		guids.append(guid);

		return guid;
	}

private:
	HashSet<UGUID> guids;
	// HashMaps to be used for imported meshes and materials
	HashMap<String, MeshPtr> meshes;
	HashMap<String, MeshPtr> meshes_animations;
	HashMap<String, MaterialPtr> materials;

};

Using Our Import Processor使用导入处理器#

我们有定制导入处理器,让我们写一个函数使用导入的内容指定的FBX当前加载UNIGINE世界。

导入函数

源代码 (C++)

/// function importing the contents of the specified FBX to the currently loaded scene
NodePtr import(const char *filepath)
{
	// creating an importer for our fbx file
	ImporterPtr importer = Import::createImporterByFileName(filepath);
	if (!importer)
		return nullptr;

	if (!importer->init(filepath))
		return nullptr;

	// creating our custom MemoryProcessor and using it to import meshes, textures, materials, and nodes without saving data to files on disk
	MemoryProcessor memory_processor;
	ImportScenePtr scene = importer->getScene();
	int num_meshes = scene->getNumMeshes();
	for (int i = 0; i < num_meshes; ++i)
	{
		MeshPtr m = Mesh::create();
		importer->importMesh(memory_processor.getImportProcessor(), m, scene->getMesh(i));
		if (m->getNumBones())
		{
			int num_animations = scene->getNumAnimations();
			for (int i = 0; i < num_animations; ++i)
			{
				MeshPtr animation_mesh = Mesh::create();
				importer->importAnimation(memory_processor.getImportProcessor(), animation_mesh,
					scene->getMesh(i), scene->getAnimation(i));
			}
		}
	}

	int num_textures = scene->getNumTextures();
	for (int i = 0; i < num_textures; ++i)
	{
		importer->importTexture(memory_processor.getImportProcessor(), scene->getTexture(i));
	}
	
	MaterialPtr mesh_base = Materials::findManualMaterial("Unigine::mesh_base");
	int num_materials = scene->getNumMaterials();
	for (int i = 0; i < num_materials; ++i)
	{
		MaterialPtr m = mesh_base->inherit();
		importer->importMaterial(memory_processor.getImportProcessor(), m, scene->getMaterial(i));
	}

	int num_nodes = scene->getNumNodes();
	ImportNodePtr root_node;
	for (int i = 0; i < num_nodes; ++i)
	{
		const ImportNodePtr &node = scene->getNode(i);
		if (node->getParent() == nullptr)
		{
			root_node = node;
			break;
		}
	}

	if (root_node)
	{
		NodePtr node;
		memory_processor.convertNode(nullptr, nullptr, node, root_node);
		return node;
	}

	return nullptr;
}

现在我们只需加载FbxImporter插件，并使用import()函数添加所需的模型。

源代码 (C++)

// including necessary libraries
#include <UnigineConsole.h>

// ...

// loading the FbxImporter plugin
Console::run("plugin_load FbxImporter");
Console::flush();
	
// importing an FBX-model directly to the scene
NodePtr imported_node = import("material_ball.fbx");

Example Code示例代码#

为了测试我们的自定义导入处理器，我们可以在SDK Browser中创建一个新的c++项目，并将下面列出的所有代码放到AppWorldLogic.h和AppWorldLogic.cpp文件中。

AppWorldLogic.h

源代码 (C++)

#ifndef __APP_WORLD_LOGIC_H__
#define __APP_WORLD_LOGIC_H__

#include <UnigineLogic.h>
#include <UnigineStreams.h>

class AppWorldLogic : public Unigine::WorldLogic
{

public:
	AppWorldLogic();
	virtual ~AppWorldLogic();

	int init() override;

	int update() override;
	int postUpdate() override;
	int updatePhysics() override;

	int shutdown() override;

	int save(const Unigine::StreamPtr &stream) override;
	int restore(const Unigine::StreamPtr &stream) override;

private:
	void run_animation(const Unigine::NodePtr &node);
	void setup_gui();
	void setup_player(const Unigine::NodePtr &node);
	void import_file(const Unigine::String &filepath);
	void dialog_file_ok_clicked(Unigine::WidgetPtr, Unigine::WidgetPtr, int, Unigine::WidgetDialogFilePtr dialog);
	void dialog_file_cancel_clicked(Unigine::WidgetPtr, Unigine::WidgetPtr, int, Unigine::WidgetDialogFilePtr dialog);
	void request_import(Unigine::WidgetPtr sender);

	Unigine::NodePtr node_;
	Unigine::String default_dialog_path{"./"};
};

#endif // __APP_WORLD_LOGIC_H__

AppWorldLogic.cpp

源代码 (C++)

#include "AppWorldLogic.h"
#include <UnigineMathLib.h>
// including necessary libraries
#include <UnigineImport.h>
#include <UnigineMaterials.h>
#include <UnigineMeshStatic.h>
#include <UnigineGame.h>
#include <UnigineWindowManager.h>
using namespace Unigine;
// our custom ImportProcessor to be used for direct memory import of scenes
class MemoryProcessor : public ImportProcessor
{
public:

	void convertNode(const NodePtr &node_parent, const ImportNodePtr &import_node_parent,
		NodePtr &node, const ImportNodePtr &import_node)
	{
		using namespace Unigine::Math;
		if (ImportCameraPtr import_camera = import_node->getCamera())
		{
			node = getImporter()->importCamera(getImportProcessor(), import_camera);
			if (node)
				node->setWorldTransform(Mat4(import_node->getTransform()));
		} else if (ImportLightPtr import_light = import_node->getLight())
		{
			node = getImporter()->importLight(getImportProcessor(), import_light);
			if (node)
				node->setWorldTransform(Mat4(import_node->getTransform()));
		} else if (ImportMeshPtr import_mesh = import_node->getMesh())
		{
			ObjectPtr object;
			if (import_mesh->isHasAnimations())
			{
				float fps = getImporter()->getParameterFloat("fps");
				auto mesh_skinned = ObjectMeshSkinned::create(meshes[import_mesh->getFilepath()]);
				if (MeshPtr animation = meshes_animations.value(import_mesh->getFilepath()))
				{
					int animation_id = mesh_skinned->addAnimation(animation);
					mesh_skinned->setNumLayers(1);
					mesh_skinned->setAnimation(0, animation_id);
				}
				mesh_skinned->setSpeed(fps);
				object = mesh_skinned;
			} else
			{
				auto mesh_static = ObjectMeshStatic::create();
				mesh_static->setMeshProceduralMode(true);
				mesh_static->applyMeshProcedural(meshes[import_mesh->getFilepath()]);

				object = mesh_static;
				object->setWorldTransform(Mat4(import_node->getTransform()));
			}

			int num_geometries = import_mesh->getNumGeometries();
			for (int i = 0; i < num_geometries; ++i)
			{
				ImportGeometryPtr geometry = import_mesh->getGeometry(i);
				int num_surfaces = geometry->getNumSurfaces();
				for (int s = 0; s < num_surfaces; ++s)
				{
					ImportSurfacePtr surface = geometry->getSurface(s);
					const int surface_index = surface->getTargetSurface();
					if (surface_index == -1 || surface_index >= object->getNumSurfaces())
					{
						Log::error("MemoryProcessor: can't find surface \"%s\".\n", surface->getName());
						continue;
					}

					if (!compare(surface->getMinVisibleDistance(), -Consts::INF))
					{
						object->setMinVisibleDistance(surface->getMinVisibleDistance(),
							surface_index);
					}
					if (!compare(surface->getMaxVisibleDistance(), Consts::INF))
					{
						object->setMaxVisibleDistance(surface->getMaxVisibleDistance(),
							surface_index);
					}

					object->setMinFadeDistance(surface->getMinFadeDistance(), surface_index);
					object->setMaxFadeDistance(surface->getMaxFadeDistance(), surface_index);

					if (ImportMaterialPtr import_material = surface->getMaterial())
					{
						object->setMaterial(materials[import_material->getFilepath()],
							surface_index);
					}
				}
			}

			node = object;
		} else
		{
			node = NodeDummy::create();
			node->setWorldTransform(Mat4(import_node->getTransform()));
		}

		node->setName(import_node->getName());

		getImporter()->importNodeChild(getImportProcessor(), node_parent, import_node_parent,
			node, import_node);

		int num_children = import_node->getNumChildren();
		for (int i = 0; i < num_children; ++i)
		{
			NodePtr child;
			convertNode(node, import_node, child, import_node->getChild(i));
			node->addWorldChild(child);
		}
	}

protected:
	// method to be called on mesh processing
	bool onProcessMesh(const MeshPtr &mesh, const ImportMeshPtr &import_mesh) override
	{
		UGUID guid = generate_unique_guid();
		import_mesh->setFilepath(guid.getString());
		meshes.append(import_mesh->getFilepath(), mesh);
		return true;
	}

	// method to be called on mesh animation processing
	bool onProcessAnimation(const MeshPtr &animation, const ImportMeshPtr &import_mesh,
		const ImportAnimationPtr &import_animation) override
	{
		meshes_animations.append(import_mesh->getFilepath(), animation);
		return true;
	}

	// method to be called on texture processing
	bool onProcessTexture(const ImportTexturePtr &import_texture) override
	{
		import_texture->setFilepath(import_texture->getOriginalFilepath());
		return true;
	}

	// method to be called on material processing
	bool onProcessMaterial(const MaterialPtr &material,
		const ImportMaterialPtr &import_material) override
	{
		UGUID guid = generate_unique_guid();
		import_material->setFilepath(guid.getString());
		materials.append(guid.getString(), material);
		return true;
	}

private:
	UGUID generate_unique_guid()
	{
		UGUID guid;
		guid.generate();

		int attempt = 100;
		while(guids.contains(guid) && attempt-- > 0)
			guid.generate();

		guids.append(guid);

		return guid;
	}

private:
	HashSet<UGUID> guids;
	// HashMaps to be used for imported meshes and materials
	HashMap<String, MeshPtr> meshes;
	HashMap<String, MeshPtr> meshes_animations;
	HashMap<String, MaterialPtr> materials;

};
/// function importing the contents of the specified FBX to the currently loaded scene
NodePtr import(const char *filepath)
{
	// creating an importer for our fbx file
	ImporterPtr importer = Import::createImporterByFileName(filepath);
	if (!importer)
		return nullptr;

	if (!importer->init(filepath))
		return nullptr;

	// creating our custom MemoryProcessor and using it to import meshes, textures, materials, and nodes without saving data to files on disk
	MemoryProcessor memory_processor;
	ImportScenePtr scene = importer->getScene();
	int num_meshes = scene->getNumMeshes();
	for (int i = 0; i < num_meshes; ++i)
	{
		MeshPtr m = Mesh::create();
		importer->importMesh(memory_processor.getImportProcessor(), m, scene->getMesh(i));
		if (m->getNumBones())
		{
			int num_animations = scene->getNumAnimations();
			for (int i = 0; i < num_animations; ++i)
			{
				MeshPtr animation_mesh = Mesh::create();
				importer->importAnimation(memory_processor.getImportProcessor(), animation_mesh,
					scene->getMesh(i), scene->getAnimation(i));
			}
		}
	}

	int num_textures = scene->getNumTextures();
	for (int i = 0; i < num_textures; ++i)
	{
		importer->importTexture(memory_processor.getImportProcessor(), scene->getTexture(i));
	}
	
	MaterialPtr mesh_base = Materials::findManualMaterial("Unigine::mesh_base");
	int num_materials = scene->getNumMaterials();
	for (int i = 0; i < num_materials; ++i)
	{
		MaterialPtr m = mesh_base->inherit();
		importer->importMaterial(memory_processor.getImportProcessor(), m, scene->getMaterial(i));
	}

	int num_nodes = scene->getNumNodes();
	ImportNodePtr root_node;
	for (int i = 0; i < num_nodes; ++i)
	{
		const ImportNodePtr &node = scene->getNode(i);
		if (node->getParent() == nullptr)
		{
			root_node = node;
			break;
		}
	}

	if (root_node)
	{
		NodePtr node;
		memory_processor.convertNode(nullptr, nullptr, node, root_node);
		return node;
	}

	return nullptr;
}

AppWorldLogic::AppWorldLogic(){}

AppWorldLogic::~AppWorldLogic(){}

int AppWorldLogic::init()
{
	setup_gui();
	return 1;
}

void AppWorldLogic::run_animation(const NodePtr &node)
{
	if (ObjectMeshSkinnedPtr skinned = checked_ptr_cast<ObjectMeshSkinned>(node))
	{
		skinned->setLoop(1);
		skinned->play();
	}
	
	int num_children = node->getNumChildren();
	for (int i = 0; i < num_children; ++i)
		run_animation(node->getChild(i));
}

void AppWorldLogic::setup_gui()
{
	auto gui = Gui::getCurrent();

	auto window = WidgetWindow::create(gui, "Import File", 4, 4);

	auto import_button = WidgetButton::create(gui, "Import");
	import_button->addCallback(Gui::CLICKED,
	MakeCallback(this, &AppWorldLogic::request_import));

	window->addChild(import_button, Gui::ALIGN_EXPAND);
	window->arrange();

	gui->addChild(window, Gui::ALIGN_OVERLAP | Gui::ALIGN_LEFT | Gui::ALIGN_TOP);
}

void AppWorldLogic::setup_player(const NodePtr &node)
{
	static const float CAMERA_PHI = 75.0f;
	static const float CAMERA_THETA = 140.0f;
	static const float CAMERA_DISTANCE = 2.0f;
	static const float FOV = 60.0f;

	using namespace Unigine::Math;

	ivec2 window_size = WindowManager::getMainWindow()->getClientSize();

	WorldBoundSphere bound_sphere = node->getHierarchyBoundSphere();

	Vec3 center = bound_sphere.center;
	Scalar radius = bound_sphere.radius * CAMERA_DISTANCE *
		max(1.0f, float(window_size.y) / window_size.y);
	quat rotation= quat(1.0f, 0.0f, 0.0f, -CAMERA_PHI) * quat(0.0f, 0.0f, 1.0f, CAMERA_THETA);

	Mat4 modelview{translate(Scalar(0.0f), Scalar(0.0f), -radius) *
		Mat4(rotation) * translate(-center)};

	mat4 projection = perspective(FOV, 1.0f, radius * 0.01f, radius * 2.0f);
	if (PlayerPtr player = Game::getPlayer())
	{
		player->setWorldTransform(inverse(modelview));
		player->setProjection(projection);
	} else
		Log::error("Main player not found.\n");
}

void AppWorldLogic::import_file(const String &filepath)
{
	if (node_)
	{
		node_.deleteLater();
		node_ = nullptr;
	}

	node_ = import(filepath);
	if (node_)
	{
		Log::message("Node loaded \"%s\" from filepath \"%s\".\n",
			node_->getName(), filepath.get());
		setup_player(node_);
		run_animation(node_);
	}
	else
		Log::error("Can't import file from filepath %s\n", filepath.get());
}

void AppWorldLogic::dialog_file_ok_clicked(WidgetPtr, WidgetPtr, int, WidgetDialogFilePtr dialog)
{
	const String filepath = dialog->getFile();
	default_dialog_path = filepath.pathname();

	import_file(filepath);

	dialog.deleteLater();
}

void AppWorldLogic::dialog_file_cancel_clicked(WidgetPtr, WidgetPtr, int, WidgetDialogFilePtr dialog)
{
	dialog.deleteLater();
}

void AppWorldLogic::request_import(WidgetPtr sender)
{
	const Vector<String> &supported_extensions = Import::getSupportedExtensions();
	const String extensions_filter = "." + String::join(supported_extensions, ".");

	auto dialog_file = WidgetDialogFile::create(Gui::getCurrent(), "DialogFile");
	dialog_file->setPath(default_dialog_path);
	dialog_file->setFilter(extensions_filter);

	dialog_file->getOkButton()->addCallback(Gui::CLICKED,
		MakeCallback(this, &AppWorldLogic::dialog_file_ok_clicked, dialog_file));
	dialog_file->getCancelButton()->addCallback(Gui::CLICKED,
		MakeCallback(this, &AppWorldLogic::dialog_file_cancel_clicked, dialog_file));

	Gui::getCurrent()->addChild(dialog_file, Gui::ALIGN_OVERLAP | Gui::ALIGN_CENTER);

	dialog_file->setPermanentFocus();
}

////////////////////////////////////////////////////////////////////////////////
// start of the main loop
////////////////////////////////////////////////////////////////////////////////

int AppWorldLogic::update()
{
	// Write here code to be called before updating each render frame: specify all graphics-related functions you want to be called every frame while your application executes.
	return 1;
}

int AppWorldLogic::postUpdate()
{
	// The engine calls this function after updating each render frame: correct behavior after the state of the node has been updated.
	return 1;
}

int AppWorldLogic::updatePhysics()
{
	// Write here code to be called before updating each physics frame: control physics in your application and put non-rendering calculations.
	// The engine calls updatePhysics() with the fixed rate (60 times per second by default) regardless of the FPS value.
	// WARNING: do not create, delete or change transformations of nodes here, because rendering is already in progress.
	return 1;
}

////////////////////////////////////////////////////////////////////////////////
// end of the main loop
////////////////////////////////////////////////////////////////////////////////

int AppWorldLogic::shutdown()
{
	// Write here code to be called on world shutdown: delete resources that were created during world script execution to avoid memory leaks.
	return 1;
}

int AppWorldLogic::save(const Unigine::StreamPtr &stream)
{
	// Write here code to be called when the world is saving its state (i.e. state_save is called): save custom user data to a file.
	UNIGINE_UNUSED(stream);
	return 1;
}

int AppWorldLogic::restore(const Unigine::StreamPtr &stream)
{
	// Write here code to be called when the world is restoring its state (i.e. state_restore is called): restore custom user data to a file here.
	UNIGINE_UNUSED(stream);
	return 1;
}

最新更新: 2023-12-19

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