Unreal Engine
Currently using UE4 (4.10.4)
Links
Unreal Engine
Blender
- Export Options (so that the object is not lying on the side after Export/Import):
- Forward: Y Forward
- Up: Z up
- Changing the object's origin to its bottom:
- Switch to Edit Mode if needed (Tab). With vertex selection on, choose the center vertex in the bottom. Press Shift+S and choose Cursor to Selected. The 3D cursor will move to the selected vertex. Deselect all and switch to Object Mode (Tab).
- In Tools choose Set Origin and then Origin to 3D Cursor.
- Make sure the object's coordinates are set to 0,0,0. Now the object should be placed properly on the XY plane.
C++
Variable names
If you want to use real variable names but have nice names in the UE editor too, then use meta/DisplayName
UPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = Camera, Meta = (DisplayName = "First Person Camera Component") )
UCameraComponent* m_pFirstPersonCameraComponent;
owner / client /server
The instance that spawned the class is always ROLE_Authority. If an Actor is spawned on the client, the client is the authority. -- OmaManfred
OmaManfred::
And concerning the owner stuff: When you spawn an instance of a class on the server FOR Client A, you have to set him as the owner. FActorSpawnParameters params; params.Owner = PlayerAPlayerController; SpawnActor<Class>(Class:StaticClass(),params); Then on Client B you can say IsOwner(PlayerBPlayerController), which should return false.
Logging
The following is just a copy/paste/change from the UE4 wiki and was really done from different persons, I am just using the work of different people here. Put it in a Log.h and include it into your <your_project>.h file after the #include "Engine.h". Because <your_project>.h is in every of your files, you will now be able to use these macros in every .cpp file.
#pragma once #include "Log.h" #include "Engine.h"
// macros
// - LOG_LINE
// - LOG -> output log
// -- LOG("text");
// -- LOG("text %s %f %d", "text", 1.2, 5);
// - PRINT -> screen
// -- PRINT("text");
// -- PRINT("text %s %f %d", "text", 1.2, 5);
#if _MSC_VER
#define FUNC_NAME TEXT(__FUNCTION__)
#else // FIXME - GCC?
#define FUNC_NAME TEXT(__func__)
#endif
#define LOG_LINE UE_LOG(LogTemp, Warning, TEXT("%s, file: %s, line %d"), FUNC_NAME, *FString(__FILE__), __LINE__);
//#define LOG_NULL(s, p) UE_LOG(LogTemp, Warning, TEXT("pointer %s %s"),s, (p?TEXT("ok"):TEXT("null") ) );
#define PRINT(format, ...) \
{ \
const FString sFunc = FString::Printf(TEXT("%s"), FUNC_NAME); \
const FString sText = FString::Printf(TEXT(format), ##__VA_ARGS__); \
const FString sMsg = FString::Printf(TEXT("%s() : %s"), *sFunc, *sText); \
if (GEngine) GEngine->AddOnScreenDebugMessage(-1, 5, FColor::White, sMsg); \
}
#define LOG(format, ...) \
{ \
const FString sMsg = FString::Printf(TEXT(format), ##__VA_ARGS__); \
UE_LOG(LogTemp, Warning, TEXT("%s() : %s"), FUNC_NAME, *sMsg);\
}
Am I client or server ?
To answer questions 1 and 2: you can use AActor::GetNetMode()
which returns whether you are a listen server, dedicated server or network client.
if (GetNetMode() == ENetMode::NM_ListenServer)
{
}
The ENetMode values are:
NM_Standalone = 0
NM_DedicatedServer = 1
NM_ListenServer = 2
NM_Client = 3 // is only when you are actually connected to a server
The ordering of the ENetMode values allows you to check multiple things at once:
GetNetMode() <= 2 means you are the server or standalone, so you have 'global authority'.
UMG with C++ base class
- create a normal UMG widget
- create a C++ class with base class UserWidget (UUserWidget)
- build the project
- set the parent class of the UMG widget to your C++ class
- in <Project>.Build.cs add "UMG", "SLATE", "SLATECORE":
PublicDependencyModuleNames.AddRange(new string[] { "Core", "CoreUObject", "Engine", "InputCore", "UMG" });
PrivateDependencyModuleNames.AddRange(new string[] { });
// Uncomment if you are using Slate UI
PrivateDependencyModuleNames.AddRange(new string[] { "Slate", "SlateCore" });
- put into <Project>.h
#include "Runtime/UMG/Public/UMG.h" #include "Runtime/UMG/Public/UMGStyle.h" #include "Runtime/UMG/Public/Slate/SObjectWidget.h" #include "Runtime/UMG/Public/IUMGModule.h" #include "Runtime/UMG/Public/Blueprint/UserWidget.h"
SLATE
https://wiki.unrealengine.com/Slate_Introduction_%E2%80%92_Basic_Menu_Part_1
The "canvas" in UMG is "SConstraintCanvas" in Slate.
Multiplayer / Sessions
Do not search for "multiplayer", search for "sessions". Good tutorial: https://wiki.unrealengine.com/How_To_Use_Sessions_In_C%2B%2B
String conversions
from: https://docs.unrealengine.com/en-us/Programming/UnrealArchitecture/StringHandling/FString
FString TestHUDString = FString(TEXT("This is my test FString."));
FName TestHUDName = FName(*TestHUDString);
FText TestHUDText = FText::FromString(TestHUDString);
Misc
Source control
The minimum you have to put under source control:
/Config /Content /Source Project.uproject
Developer Folder
If you have the developer folder(s) enabled "Content / View Options / Show Developers Content" then make sure to reference it from outside when cooking a project.
Other Licenses (examples)
not allowed
- GNU General Public License (GPL),
- Lesser GPL (LGPL) (unless you are merely dynamically linking a shared library), or
- Creative Commons Attribution-ShareAlike License.
Code or content under the following licenses, for example, are allowed
- BSD License,
- MIT License,
- Microsoft Public License, or
- Apache License.
Other
Escape key stops simulation in editor
If you want to change this behavior, open "Edit/Editor Preferences" and search for "stop". Then change under "Play World/Stop" the shortcut "Escape" to whatever you want, for example shift-Escape.
Black Screens or flickering/invisible new action popup
Details/Text/Line-Break
If you are shown a text in the Details tab, chances are you can use shift-return to create a line break.
