Repair ribbon hole
The intention of those mini tutorials is to have simply searchable reference for the implementation of fundamental concepts in Niagara.
Right now I need to have a fast take a look at how we would remedy a standard problem when utilizing Ribbons.
Except you spawn a particle each single body, there’ll at all times be a niche between the supply of the ribbon and the ribbon itself.
Spawning a particle each body, is usually a resolution in some instances, but it surely’s typically higher to discover a resolution in which you’ll be able to bridge that hole
There are a couple of methods to cope with this, however I’d wish to current a reasonably fundamental one that can work in a lot of conditions.
Primary Setup
The technique right here will probably be to reliably discover the final spawned particle and snap it to our supply location (the emitter place on this instance).
We do that by, for each particle, evaluating the index of that particle with the full variety of particles which were spawned within the emitter. Within the case that we do have the final spawned particle, we set the Place of the particle to the simulation place.
Now to know the full variety of particles we nonetheless have to maintain observe of that in some way.
To do that, we’ll alter the SpawnPerUnit and SpawnRate modules. (You’ll in all probability need to create a replica for this.)
On the finish of the modules we are able to add a bit part that reads the spawn rely and provides it to Emitter.TotalParticlesSpawned.
And increase now the final particle of your ribbon will stay connected to the supply.
Besides that’s not fully the case.
Resulting from tick order it’s potential that this script will probably be executed earlier than the motion script of the supply.
This may create a one body hole between the final particle and the supply.
We will remedy this on a case by case foundation, by forcing the Niagara Tick to later within the body.
That is usually in poor health suggested as a result of it takes away the engines potential to utilize threading in an environment friendly method, but when used sparingly it may be useful.
And there you go, a fairly strong approach to make your ribbons gap-less.
Take pleasure in.
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After GPU Ribbon is obtainable to Niagara I’m not too bothered with this problem, however I nonetheless need to share a much less correct however barely simpler resolution to the hole problem when utilizing Spawn Price.
This method assumes the consumer to stay with a relentless spawn fee worth, as a result of there’s little or no level of randomizing the spawn fee worth each body in a ribbon emitter. Anyway as a result of the spawn fee worth is fixed, we are able to merely calculate the spawn interval in second by 1/SpawnRateValue, then in Particle Replace stage, do a Lerp Place and select between SimulationPosition and Particles.Preliminary.Place by checking if the Particles.Age is smaller than the spawn interval.
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@ifurkend Humorous sufficient, somebody asking tips on how to do your described technique for spawn per unit, is what triggered me to search for the offered technique.
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If we’re speaking about the identical man, he truly needed the most recent particle to transcend the actor place, which is feasible with our strategies, but it surely saddens me that it not issues now (not due to the GPU ribbon).
