Blueprint Essentials: Using Loops Level Design | 10 | v4.2 Tutorial Series | Unreal Engine

alright so in the last video I showed you how for loops work and that was really cool but really all we were doing is printing stuff out to the screen what I want to do now is take just a second kind of as an added bonus and show you something pretty cool and pretty practical that you can do with 4 loops so I'm doing this completely off the top of my head with no notes I'm gonna right-click make a new blueprint make an actor and we're gonna call this procedural wall we're gonna make a procedural wall system and it's gonna be amazing and you're gonna be really happy about it so let's see here we are in our components list the first thing I'm gonna do is add a scene component this is honestly this is it for the most part just habit for me and we'll call that route now over in the content browser I have the starter content so I'm gonna go under architecture and I'm gonna grab this pillar here so it's a little fifty by five hundred pillar and I'll drag that into my component list and we'll call this base wall and what we'll do is we'll just copy this over and over again in order to make our wall actually happen so there we go that should be all we need let's go ahead and jump over to the graph and I'm gonna show you more things than just loops so we're gonna do something that's kind of sort of fancy we're gonna create a new variable and we're gonna set its type over to a vector and we'll call this end point and we're gonna set it to be editable and we're going to show its 3d widgets and let's give it a tooltip let's say this is the end of the wall with an exclamation point because that makes tooltip superior okay so if I drag this out of the way and let's go over to our blueprints list blueprints folder excuse me we can bring in procedural wall and it has that little endpoint variable which we can click on and we can move so that's the literally the value for that endpoint right there okay cool now we need to make that do something what I want to do is drive everything inside the construction script that way we can move that endpoint around and make our wall get bigger and smaller right there live in the editor now the first thing I want to do is bring in my endpoint I'll get a getter because I want to pull some information from it and we're gonna make sure that it is not equal to zero so I'm just gonna hit the exclamation point and grab a not equal node and if it's not equal to zero let's fire off a branch I can plug that into the construction script really all we're doing here is we're saying if we are not equal to zero then we're gonna do stuff if the end point is equal to zero then it hasn't moved and we don't really need to do anything so it's kind of a check and balance to make sure we're not doing anything we don't necessarily have to also I'm gonna take the end point and we're gonna drag a wire out from it here and we will multiply it by another vector and I'm going to multiply it by one for X 1 for Y and 0 for Z because I don't really want the vertical side of it to even be calculated I don't I don't care about the vertical elevation for that little endpoint so again we're just we're gonna leave that plugged into the first entry for not equal two and there we go ok so now next thing if our branch is true then our little endpoint has been moved somehow because it is no longer sitting in relative zero zero zero so now we want to run a loop and this must be a regular for loop we're not gonna worry about what the loop does yet we're gonna worry about how we figure out the loop now as a reminder my little pillar that I used my little pillar it is it has dimensions of 50 by 500 so we know that it's 50 in width and 50 in depth and then it's 500 tall so let's use that to our advantage what we're gonna do is grab the endpoints so let's get another copy of that I'm certain that ctrl-c ctrl-v it'll just keep wires from going everywhere and I'm going to get the vector length there's a node that will do that and that is just going to return a float value that represents the length of this vector which is perfect that is exactly what we need we are then going to divide this by 50 which is we what we know is our dimension for the pillars now if that needed to be a variable like if that had to be influx you could make that a variable and you could set that to be like the bounds of another mesh or something we're gonna keep this simple we know our pillars 50s or just gonna divide by 50 then we need to round this down and the easiest way to do that well we're kind of just gonna truncate it so let's just run a floor on it and that will output an integer so if we had a value that was like three point seven to nine we're just gonna get three and that can become our last index we'll take our first index and just set that to one all right so that's looking pretty good so far now I need to figure out what we're gonna do to create our wall well we need to start making static meshes so let's see do we have our little pillar over here selected it looks like we do so let's right-click and we will add static mesh and you'll see there's add pillar 50 by 500 as static mesh component boom perfect now we do a couple of fancy things we're gonna connect that to the loop body because each time the loop runs we want it to create another one of these and we're going to set it to be manually attached that means we need to okay well I guess I should step back this is being added as a static mesh component literally a part of this blueprint another component we're gonna set it to manual attachment which means we must manually parent it to something else in our blueprint components so let's go ahead and do that next so here is the component that just got created so we'll say attach and there's an attached to node so that's what we want the in parent is going to be the base wall that is that first little wall that we created that's already there the attach type it almost doesn't matter but I'm gonna set it to keep world position anyway now the last thing we need to do is move this into place so we've created it we've parented it to the baseball now we need to move it into its appropriate position that should be fairly easy because we know that it is 50 it's wide now we can take that 50 units and we can multiply it by our current index of the loop because the first time the loop runs the index is gonna be 1 the next time it runs it's gonna be 2 and 3 and 4 and so on and so forth so let's just start by multiplying integer by float and we're gonna multiply this by 50 the reason I chose a float is that that's automatically going to convert my final value to a float that's super useful for me because I'm going to use this and make a vector and we'll use the x value there then we're gonna take the result of this vector and use it actually let's just take our return value here off of our add static mesh and we will say set relative location I'll plug that in that'll be the last thing in our chain and this can be the new location now this should already do something we should probably go ahead and test it you see it's fairly simple so far hasn't been too hard to put together let's compile I window out actually you know what let's put this up here on the tab I can just jump between the two that'll be nice and easy and it's already doing something let's take our end point and as I drag it out check that out we're getting more and more wall segments depending on how far away we move the end point which is cool but it would be nicer if the wall was actually rotated to snap to the end point so let's fix that next so jump to the back of the procedural wall and we could comment all of this we could say all this and then hit C and creates new wall segment based on distance of endpoints now once the loop is completed by the way if you see an error on your loop always hit compile because it may may or may not be a real error so we'll go ahead and when we're completed the last thing we want to do after we've finished creating and parenting and doing all that fun stuff is then we'll handle our rotation so what we're gonna do is rotate the base wall so let's get that and we will actually just drag a wire off of that and we'll say set world rotation like so and we'll just plug that in now what are we gonna set it to that's the real question well we need to figure out the rotation that is represented from the start point of the actor to the end point that way like what would we have to rotate to if the end point was moving around like so how would we make that happen well the good news is that's pretty easy to do we just need a little bit of vector math we're gonna start with the actor location so we'll say get actor location and then we need the end point and from the the actor location we can say find look at rotation so you can literally feed that a start point and end point it's kinda like saying stand at the start point and look toward the target and then feed back the rotation required to to look at that now for the target we're going to take the actor location and we're going to add that to the end point like so and that'll give us the rotation that we need then we're actually going to break that and all we're gonna use is y'all we don't want pitch and roll so I'm gonna take y'all and right now we're gonna make a rotator so in essence that's just nullifying pitch and roll and we'll plug that into our new rotation and let's compile and let's see we good oh it looks like it's already working so now if I take the end point I can just move it around and I get a little auto wall that just fits perfectly into any given location I can take the original point and I can use that to position the wall like so so we can slap that right over here we can take the end point and let's just kind of cordon off this section we don't want anybody coming over there cool and once that's ready we can hit play and check it out we have a wall and it looks just like a regular wall boom can't move through it it's pretty awesome you see there's a couple little shadowing things with this approach like as you get distant you can kind of see the gaps in the shadows but yeah it shows how you could go about doing this honestly if I was creating a setup like this I'd do it for like a picket fence or or something like a railway I wouldn't necessarily do it with a solid wall like this but it is pretty cool cuz for a solid wall you could just scale the object right and that would work just fine but this is a nice way to kind of go about proving the point so I guess one other thing we could do just cuz that yeah okay I want to show one more thing let me jump back into the blueprint you can't close the video now if you really want to if you feel like you've learned everything you need to learn let's go back into components and I'm gonna swap out the base wall with another mesh let's do the one that has the doors in it we go under there we go so wall door 400 by 300 let's see 400 by 400 I like the tall ones better so we'll do that and then let's go back over to our graph and that is also adding in that guy so static mesh oh well I mean go ahead make sure I select that one so let's jump over to Architecture and 400 by 400 make sure we have that selected and then over in our blueprint we can right click and say add static mesh boom and I'm just gonna replace this guy we're gonna say you go there you go there you go there and you go there then I can remove this one out altogether make sure we reset manual attachment now we do need to update our width so we know that's 400 so I'm just gonna hard code that's 400 I mean at this point probably you gotta just set that to a variable so you could adjust it later but you know the drill at this point all right cool and it's already working so now as I take my endpoint and I increase it out we get more and more copies of the wall that have doors in them which is actually a little cooler to show off in this case because you can use those gaps right so you can run in and out of each one so now you've seen a practical approach to using for loops to create procedural elements for your levels that is going to wrap things up for this video thanks a lot

Channel: Unreal Engine

Views: 128,909

Keywords: UE4, Blueprints, basics, essentials, loops, Unreal

Id: kmnC6IUPGjI

Length: 13min 38sec (818 seconds)

Published: Wed May 28 2014