Help on how to get Widget slider scaling static mesh actors within blueprints

[willeb2020]

I’m relatively new to Unreal programming and have been trying on and off for weeks to get my Slider Widget to communicate and scale many blueprints with static mesh actors within.

This is to allow me to scale either all my Heirarchical instanced static mesh actors, or PCG actors from the slider when in game.

Would really appreciate some help.

[Everynone]

@willeb2020

my Slider Widget to communicate and scale many blueprints with static mesh actors within.

How do you want to decide which static mesh actors you want the slider to talk to?

[willeb2020]

Hi thanks for replying. I was imagining adding a parameter within each Blueprint Actor, which can be linked to the widget slider

[willeb2020]

What I’m trying to do is show a number of Blueprint Actor trees grow over time, so you can set the slider to year, and this will update each blueprint actor, and as some trees grow faster than others, each blueprint actor would need a slightly different scale maths based on the year/age

[Everynone]

• create a base Static Mesh Actor Tree:

Create a bunch of children (saplings?!). Add them to the level.

• the base tree class has a Growth Rate variable and a Custom Event waiting for the Time update:

Give the tree a tag, optionally add extra tags to the specific trees if you need to identify them or fetch only some trees (maybe we’re ready to harvest all cherries)

• have the widget with a slider send the time update to all trees (or some trees based on their tags):

• child classes can override growth math (if at all necessary since their variable already describes the growth rate)

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Hope that works for you.

[willeb2020]

Thank you so much for your reply Everynone.

I have followed your steps and got it working, however I guess I’ve made a mistake as only one of my 3 child static mesh actor scales at a time. and has something to do with the one I currently have selected.as is the last I created.

Here is the static mesh actor

here are the static mesh actor blueprints, the only difference i can see is I have a ‘Max Once Per Frame’ option in ‘Set TImer by Event’

And the slider blueprints:

I also tried it for a PCG but it didnt update the spawned actors, I will ask that in a seperate question.

Thanks again for your help, its really appreciated! What a great forum!!!

[Everynone]

Re: the blue ↓? node - not sure how you grow trees, I used a Timer to demo it - not necessarily the best way to grow trees. Focusing on the comms/architecture. The node, however, is a Timer Handle - it holds its data, can be used to pause, query remaining time, reset it and so on.

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@willeb2020

only one of my 3 child static mesh actor scales at a time

• ensure the instances have growth rate other than 0
• ensure they all have a tag
• ensure they are present in the world when the widget initialises and binds the dispatcher

This will not work for dynamically spawned trees (not as is), you’d need to bind dynamically.