UE Python笔记

插件

官方

商城

Python Editorhttps://www.fab.com/listings/f4c99ba0-1a86-4f6a-b19d-2fd13f15961b

GitHUB

好像只更新到了2020年4.2x的版本。可能有大佬改了5.x的版本。也希望分享给我一份。谢谢

https://github.com/20tab/UnrealEnginePython

学习笔记

网上教程一大堆。边学边写。学会到哪写到哪。哪天不更新了。就是这个笔记又太监了。写的不对的地方喷的时候也麻烦轻点。

Sequencer中的Python脚本https://dev.epicgames.com/documentation/zh-cn/unreal-engine/python-scripting-in-sequencer-in-unreal-engine?application_version=5.0

UE 使用Python控制Sequencehttps://zhuanlan.zhihu.com/p/13347612063

这下面这个文档解释的比较细：

UE5 中用 Python 接口创建 Level Sequence 与设置 TriggerEvent-腾讯云开发者社区-腾讯云遇到了一个美术需求，需要批量读取一段动画，制作成 UE 中的 Level Sequence，然后给动画添加几个 Event Track。随后，需要在 Event Track 中添加 Trigger Event，设置插件 uDraper 布料的缓存数据路径。总之，最终效果如下：https://cloud.tencent.com/developer/article/2146577

跟着学的案例

目前还没“复刻”成功=复制粘贴都不行.gif：

复刻成功=没学会：

1.这个Json文件少了个]。其他按照他这个做基本能复刻。

UE5 Python脚本自动化Sequence Key帧_ue sequnece python-CSDN博客

2.Json（latitude，longitude，elevation）= Python(uex，uey，uez)。因为我没有PythonEditor所以改成了固定的main方式。

【UE4】Python读取Json数据创建对应关卡序列_json设计关卡-CSDN博客

Json相关

读取（祖传代码）

(filename = 外部输入的名字）特别要注意的是Json格式问题。

 #def JsonGetData(filename):
    # 读取/项目目录/JsonFile中的JSON文件数据存入json_data
    root_path = unreal.SystemLibrary.get_project_directory() + 'Content/Json/'
    final_path = root_path + filename + '.json'
    fp = open(final_path, 'r', encoding='utf-8')
    json_str = fp.read()
    json_data = json.loads(json_str)
    unreal.log("=== INFO: Json Get OK ===")
    return json_data

报这个错误就是Json格式出现问题了。

JSON在线 | JSON解析格式化—SO JSON在线工具

解析

示例 
"commands": [
   {
     "commandtype": "Create",
     "objectcreateinfo": {
       "object": {
         "id": "1",
         "objecttype": "myship"
       },
       "propertys": [
         {
           "key": "DisplayName",
           "value": "我的船",
           "propertytype": "String",
           "displaystring": "我的船"
         }
       ],

 #读取各项数据创建关键帧
 commands = json_data["commands"]

#循环获取commands里面的数据
 for index in range(0,len(commands)):
 #for command in commands:

     #json中commandtype为Create时执行
     if commands[index]["commandtype"] == "Create":
          
         # 获取到"commands->objectcreateinfo->object->objecttype"这一层是否等于myship
         if commands[index]["objectcreateinfo"]["object"]["objecttype"] == "myship":

Main方法

没有这个函数的话。直接右键运行是不会执行任何东西的。

//有这个右键脚本运行才能有效
if __name__ == '__main__':
    create()

python获取场景中的actor

  # 获取Actor子系统以抓取选定的Actor
  actor_system = unreal.get_editor_subsystem(unreal.EditorActorSubsystem)
  # 获取选定的Actor
  actor = actor_system.get_selected_level_actors()[0]
 
  # 将Actor作为可拥有物添加到关卡中
  actor_binding = level_sequence.add_possessable(actor)
 
  
  # 刷新以直观地查看添加的新绑定
  unreal.LevelSequenceEditorBlueprintLibrary.refresh_current_level_sequence()

# 使用绑定将轨迹添加到Sequencer（由轨迹类型指定）
  transform_track = actor_binding.add_track(unreal.MovieScene3DTransformTrack)

属性/状态

    #transform
    # 将分段添加到轨迹以便能够设置范围、参数或属性
    transform_section = transform_track.add_section()
  
    #位移:
    获取位置的xyz通道
    channel_location_x = transform_section.get_channels()[0]
    channel_location_y = transform_section.get_channels()[1]
    channel_location_z = transform_section.get_channels()[2]

    #获取旋转yz的关键帧
    channel_rotation_x = transform_section.get_channels()[3]
    channel_rotation_y = transform_section.get_channels()[4]
    channel_rotation_z = transform_section.get_channels()[5]

     #添加关键帧
     links = json_path["links"]
     for index in range(0, len(links)):
     new_time0 = unreal.FrameNumber(value=index*int(json_path["fov"]))
     #channel_fov.add_key(new_time0, float(json_path["fov"]), 0.0)
     channel_location_x.add_key(new_time0, float(links[index]["x"]), 0.0)
     channel_location_y.add_key(new_time0, float(links[index]["y"]), 0.0)
     channel_location_z.add_key(new_time0, float(links[index]["z"]), 0.0)
     channel_rotation_x.add_key(new_time1, float(links[index]["roll"]), 0.0)
     channel_rotation_y.add_key(new_time1, float(links[index]["pitch"]), 0.0)
     channel_rotation_z.add_key(new_time1, float(links[index]["yaw"]), 0.0)
        
    
      #设置显示隐藏:
      #为actor添加可视性(隐藏)关键帧
      channel_visibility_bool = visibility_section.get_channels()[0]

      #添加关键帧
      channel_visibility_bool.add_key(new_time,False)

获取蓝图自定义的变量（感谢DeepSeeK）

import unreal

# 方法1：获取当前关卡中所有蓝图实例
def get_blueprint_variable(actor_class_name, variable_name):
    # 获取当前关卡所有Actor
    actors = unreal.EditorLevelLibrary.get_all_level_actors()
    
    # 遍历查找目标蓝图类实例
    for actor in actors:
        if actor.get_class().get_name() == actor_class_name:
            # 检查变量是否存在
            if actor.property_exists(variable_name):
                value = actor.get_editor_property(variable_name)
                print(f"Found variable '{variable_name}': {value}")
                return value
            else:
                print(f"Variable '{variable_name}' not found in actor.")
                return None
    print(f"Actor of class '{actor_class_name}' not found.")
    return None

# 使用示例：获取类名为"MyBlueprintClass"的Actor的"MyVariable"变量
get_blueprint_variable("MyBlueprintClass", "MyVariable")

# 方法2：通过选中Actor获取（需提前在编辑器中选中）
selected_actors = unreal.EditorLevelLibrary.get_selected_level_actors()
if selected_actors:
    actor = selected_actors[0]
    value = actor.get_editor_property("MyVariable")
    print(f"Selected actor's variable value: {value}")

#我自己是用的这个写法（上面都是DeepSeek发的）
 # 获取Actor子系统以抓取选定的Actor
 actor_system = unreal.get_editor_subsystem(unreal.EditorActorSubsystem)
 # 获取选定的Actor
 actor = actor_system.get_selected_level_actors()[0]
 print(actor)
 value = actor.get_editor_property("TestInt")

Sequence添加Int/float轨道

 #  创建整型轨道（int）
 int_track = actor_binding.add_track(unreal.MovieSceneIntegerTrack)
 property_name_int = "VAR_Index"
 int_track.set_property_name_and_path(property_name_int, property_name_int)

  #将分段添加到轨迹以便能够设置范围、参数或属性
 int_section = int_track.add_section()
   #设置开始和结束帧数
 int_section.set_start_frame_seconds(0)
 int_section.set_end_frame_seconds(600)
 channel_int = int_section.get_channels()[0]  # 假设第一个通道是整型通道     

  #  创建浮点轨道（假设变量类型为float）
 float_track = actor_binding.add_track(unreal.MovieSceneFloatTrack)
 property_name = "Alpha"
 float_track.set_property_name_and_path(property_name, property_name)

 #将分段添加到轨迹以便能够设置范围、参数或属性
 float_section = float_track.add_section()
   #设置开始和结束帧数
 float_section.set_start_frame_seconds(0)
 float_section.set_end_frame_seconds(600)
 channel_float = float_section.get_channels()[0]  # 假设第一个通道是float通道

 links = json_path["links"]
 for index in range(0, len(links)):
     new_time0 = unreal.FrameNumber(value=index*int(json_path["fov"]))
     #channel_fov.add_key(new_time0, float(json_path["fov"]), 0.0)
     channel_int.add_key(new_time0, float(links[index]["va"]), 0.0)
     #print("index",float(links[index]["va"]))
     #float_track.add_key(new_time0, float(links[index]["al"]), 0.0)
     channel_float.add_key(new_time0, float(links[index]["al"]), 0.0)

尝试

Json

{
  "starttimestamp": 0,
  "endtimestamp": 600,
  "frametime": 60,
  "seqname": "VideoPlayerSeqSpline",
  "fov": 60,
  "links": [
    {
      "x": 0,
      "y": 0,
      "z": 0
    },
    {
      "x": 1088.2844551244866,
      "y": -6.1749946553391055e-05,
      "z": 9.0949470177292824e-13
    },
    {
      "x": 962.03462911456836,
      "y": 1326.0205919409059,
      "z": -2.1247876702545909e-07
    },
    {
      "x": 1655.6119959682651,
      "y": 1939.9672775097956,
      "z": 6.2318827929175313e-06
    },
    {
      "x": 2921.7209372361831,
      "y": 1163.8111134544288,
      "z": -1.546140993013978e-11
    },
    {
      "x": 3168.7212710348158,
      "y": -502.86935341987612,
      "z": 36.471531137039221
    },
    {
      "x": 3168.7212776581878,
      "y": -1900.5658369533642,
      "z": 36.471531137031945
    },
    {
      "x": 3168.7212858682856,
      "y": -2762.9053314381854,
      "z": 15.992892525690252
    },
    {
      "x": 1705.8193762352209,
      "y": -2821.7894823782708,
      "z": 15.992892525679338
    },
    {
      "x": 1705.8193759169985,
      "y": -1617.7851900597982,
      "z": 15.992892525679792
    },
    {
      "x": 273.03898678036694,
      "y": -1617.7851516590028,
      "z": 15.992892525679792
    }
  ]
}

Python

#连接虚幻API库
import unreal,json,os
 
def JsonGetData(filename):
    # 读取/项目目录/JsonFile中的JSON文件数据存入json_data
    root_path = unreal.SystemLibrary.get_project_directory() + 'Content/Json/'
    final_path = root_path + filename + '.json'
    fp = open(final_path, 'r', encoding='utf-8')
    json_str = fp.read()
    json_data = json.loads(json_str)
    unreal.log("=== INFO: Json Get OK ===")
    return json_data
 
def Seqcreate():
    json_path = JsonGetData("test")
 
    # 获取资产工具
    asset_tools = unreal.AssetToolsHelpers.get_asset_tools()
 
    # 在根内容文件夹中创建一个名为LevelSequenceName的关卡序列
    level_sequence = unreal.AssetTools.create_asset(asset_tools, asset_name=json_path["seqname"],
                                                    package_path="/Game/Sequence/",
                                                    asset_class=unreal.LevelSequence,
                                                    factory=unreal.LevelSequenceFactoryNew())
    # 创建一个帧率对象并设置为所需的fps数值
    frame_rate = unreal.FrameRate(numerator=json_path["frametime"], denominator=1)
    # 设置显示速率
    level_sequence.set_display_rate(frame_rate)

    # 设置播放范围
    level_sequence.set_playback_start(json_path["starttimestamp"])
    level_sequence.set_playback_end(json_path["endtimestamp"])
 
    # 获取Actor子系统以抓取选定的Actor
    actor_system = unreal.get_editor_subsystem(unreal.EditorActorSubsystem)
    # 获取选定的Actor
    actor = actor_system.get_selected_level_actors()[0]
   
    # 将Actor作为可拥有物添加到关卡中
    actor_binding = level_sequence.add_possessable(actor)
   
    
    # 刷新以直观地查看添加的新绑定
    unreal.LevelSequenceEditorBlueprintLibrary.refresh_current_level_sequence()

  # 使用绑定将轨迹添加到Sequencer（由轨迹类型指定）
    transform_track = actor_binding.add_track(unreal.MovieScene3DTransformTrack) 

    # 将分段添加到轨迹以便能够设置范围、参数或属性
    transform_section = transform_track.add_section()
  
    transform_section.set_start_frame_seconds(json_path["starttimestamp"])
    transform_section.set_end_frame_seconds(json_path["endtimestamp"])

    channel_location_x = transform_section.get_channels()[0]
    channel_location_y = transform_section.get_channels()[1]
    channel_location_z = transform_section.get_channels()[2]
   

    links = json_path["links"]
    for index in range(0, len(links)):
        new_time0 = unreal.FrameNumber(value=index*int(json_path["fov"]))
        #channel_fov.add_key(new_time0, float(json_path["fov"]), 0.0)
        channel_location_x.add_key(new_time0, float(links[index]["x"]), 0.0)
        channel_location_y.add_key(new_time0, float(links[index]["y"]), 0.0)
        channel_location_z.add_key(new_time0, float(links[index]["z"]), 0.0)

         
    unreal.EditorAssetLibrary.save_loaded_asset(level_sequence, False)
    # 刷新以直观地查看新增的轨迹和分段
    unreal.LevelSequenceEditorBlueprintLibrary.refresh_current_level_sequence()
 
    unreal.log("=== INFO: Seq Create Completed Please check the file===")

if __name__ == '__main__':
    Seqcreate()