Search in
Sort by:

Question Status:

Search help

  • Simple searches use one or more words. Separate the words with spaces (cat dog) to search cat,dog or both. Separate the words with plus signs (cat +dog) to search for items that may contain cat but must contain dog.
  • You can further refine your search on the search results page, where you can search by keywords, author, topic. These can be combined with each other. Examples
    • cat dog --matches anything with cat,dog or both
    • cat +dog --searches for cat +dog where dog is a mandatory term
    • cat -dog -- searches for cat excluding any result containing dog
    • [cats] —will restrict your search to results with topic named "cats"
    • [cats] [dogs] —will restrict your search to results with both topics, "cats", and "dogs"

Office Holiday

Epic Games' offices will be on holiday from June 22nd to July 7th. During this period support will be limited. Our offices will reopen on Monday, July 8th. 


When interacting with blueprints though C++, you can modify the C++ members through UPROPERTYs to your heart's content, but when it comes to UFUNCTIONs, the inputs need to remain const. Why is that?

I have a situation where I want UMG to launch a rocket to another planet when I hit a button, and have the rocket class internally track the destination until it arrives:

 UFUNCTION(BlueprintCallable, Category = "Mechanics")
             virtual void launch(AActor* &destination);

AActor* &destination would need to be non-const, because the member I'm assigning that destination to will repeatedly change as the rocket goes from planet to planet. Unfortunately, even though the return is void, it still sets up &destination as an output in the blueprint.

I also have a function that should allow UMG to set the rocket's location based on actor and offset from the actor:

 UFUNCTION(BlueprintCallable, Category = "Mechanics")
     virtual void setLandedLocation(AActor* &body, const FVector offset = FVector(0, 0, 0));

The parameter AActor* &body also needs to be non-const, because the body will eventually change when the rocket goes from planet to planet.

Abstracting away members and variables is nice way to keep classes bug-free, so I'm slightly confused as to why OOP getters and setters are not allowed in UFUNCTIONS.

Am I missing something here?

Thank you, BeariksonStudios

Product Version: Not Selected
more ▼

asked Dec 13 '14 at 07:50 PM in C++ Programming

avatar image

108 2 5 10

(comments are locked)
10|2000 characters needed characters left
Viewable by all users

0 answers: sort voted first
Be the first one to answer this question
toggle preview:

Up to 5 attachments (including images) can be used with a maximum of 5.2 MB each and 5.2 MB total.

Follow this question

Once you sign in you will be able to subscribe for any updates here

Answers to this question