Randomly Placing Objects with PARTICLES in Blender

what's up guys justin here with the cg essentials dot com back with another blender tutorial for you so in today's video we're going to talk about how to use particle systems to start randomly placing objects on surfaces inside a blender so let's go ahead and just jump into it all right so there's a lot of applications when you're 3d modeling about how you might want to randomly place objects on surfaces so there's a lot of reasons for this you might want to create like a city or you might want to take a number of trees or something like that and place them on a surface randomly and so we're going to talk about one way to do that which is to use the particle settings and so the particle settings can be found you're going to click on an object because these particle settings get associated with an object kind of like a parent but basically what we've done is we've selected this plane and you want to go down you want to select the option for particle properties and so what you're going to be able to do here is you're going to be able to manage your particle systems inside a blender and so in this situation what we want to do is we want to add a particle system to this plane so to start off we're just going to click the little plus button right here that's going to add a particle system slot and so notice how what that did is that placed an object on this face and we have all these options that show up down here and right now this is set to be an emitter and so what he what an emitter does is it's going to emit objects so if you were to create like an animation and wanted to create like sparks or other things like that you could do that using the emitter settings in this video we're going to focus more on the hair settings because those are used in order to actually place objects on objects so we can talk about emitter settings in a future video if you're interested but to start off what we want to do is we want to switch over to hair so when we switch over to hair notice how you get exactly what it sounds like you get hair inside of your model so what it's doing is it's placing a thousand hairs on this surface randomly and so we're gonna go ahead and bring this length down just so we can look at this but if you look in your mission settings that's where you're going to set the number of objects that are being placed in here as well as things like the seed which is going to adjust the placement on the face the length or size of these objects other things like that and so right now though this is creating hair which isn't what we want well the particle systems inside a blender not only can be set to place hair randomly they can also be set to place objects randomly and so to do that and i'll go ahead and minimize these just so you can see everything down here in order to place objects on your surface instead of generating hair you want to go down to your render options and inside of your render options there's an option in here to adjust what you're rendering as so at the moment these are being rendered as a path that's generating hair well we want to set this so that these are rendered as objects so you want to click the little drop down you want to select the option for object and so in this situation what we need to do now is we need to set the object that's going to be placed on this surface so in this situation the object we want to place is going to be this cube and so in order to do that all you need to do is click the little eyedropper right here and go find your cube and click on it and so what that's going to do and these came in kind of small so i'm going to size them up a little bit that's going to randomly place a number of these objects on your surface so it's basically creating a particle system made up of these cubes and so you can make changes under your emission settings for like the number of cubes so let's say you wanted less cubes in here you could bring this down to a value of like 150 or something like that so place as many or as few objects as you give it a value to do inside of your inside of your model and so now what we need to do and so let's take a look at some of the options for what we can do to this cube once it's been placed so for example you can adjust the size of your cube by either adjusting the scale inside of your render settings down below or by adjusting your hair length up above so these are both going to adjust the size of your cubes right here so you can use that to adjust the size another thing you might notice is you might notice that these cubes are all getting placed halfway through my plane right so they're partially above partially below so this is because so these are getting brought in based on the object origins and the origin is basically the location where the axes intersect for your object and so if we were to select this object right here go up into our options and click on the button for origins you can see how the object origin is right in the center of your cube what that means is that means that everyone these are being placed based on that origin location so for every one of these that's being placed on this surface it's being placed based on that central point well all we need to do is i'm going to go ahead and i'm going to turn on vertex snapping just to make sure that we're being precise and then under options i've selected origins so now if we make a transform it's only going to move my origin i'm going to move my object origin to the corner so when i move my object origin to the corner you can see how these are now being placed on based on that corner point rather than the central point so now they're all sitting on top of the surface so your object origins are going to affect the placement point of your particle system and so let's say that we wanted to randomize these a little bit and so these are all exactly the same size and they look really uniform and so what i want to do is i want to add some randomness to their size so i'm going to do that by going under my render settings and adjusting the object randomness like this so you can see how when this happens i can adjust this anywhere from 0 to 1 and this is really going to adjust the size of the objects that are placed in here so let's say i wanted some of these to be smaller i could set this to like .5 or something like that notice how now we have a lot more randomness in our size in here the cool thing about this is these are all still being placed based on that object origin meaning they're all still directly on the surface and so let's say that we also didn't want these all facing the same direction all we can do is we can add some randomization using the rotation function but you can't see a rotation function in here right now right so there is no rotation drop down in here well to access that you need to click on the button for advanced so notice how when you click on advanced this adds a couple options including velocity and rotation well we want to check the box for rotation we'll talk more about this in a little bit for making sure everything's oriented properly but for now let's check the box and what we want to do is right now this is set to have an orientation axis of velocity slash hair and so what that means is that means if we try to randomize this nothing is going to happen but let's go through and let's set the orientation axis so that it's aligned with a global z and so global z is just going to orient all of these so that they're straight up and down based on the blue axis but the other thing that allows us to do is that allows us to randomize the rotation of our objects so you can see how i can adjust my random phase right here like this and those will rotate randomly along the z axis so you you can also adjust if they're facing up and down like this so you can adjust randomizing this so you're basically randomizing your orientation axis right here you can do that if you want these to look like they all kind of fell down or you can just leave them on zero and use this to randomize rotation without changing anything else and so let's say that we wanted to add a second particle object to this surface and so first off let's click in here and let's rename our first particle system to cubes so you can just double click on this and type in order to rename this and now let's add another particle system slot so we're just going to click the plus button notice how this does the same thing well now let's add some cones to this face so we're going to go to hair we're going to go down to render render as object instance object cone so what that's going to do is that's going to place a cone in here and so notice how for our cones the orientation is wrong and so what we need to do is we just need to turn on our advanced settings adjust our rotation and then to set our orientation axis to the global z or these may need to be the global x in this situation so if you set these to the global x then they're going to face up and down and notice how you're having the same issue that we had before where um these are halfway through our plane right here well all we need to do is just click into our base object and adjust our origin so we're just going to move our origin down and we'll align this with the center of the bottom of our object we'll go back and turn this off go back and look at our particle system and so we can also go back and adjust our size as well as the number of cones that we have in here and so not only does this work for flat objects like this one it also works for objects like this one which is more of like a billowy plane that i created using the uh the ant landscapes add-on which i will link to in the notes down below but we can do the same thing with a particle system with this cone or this cylinder so we're just going to click in here click the plus button we'll go to hair render as object and we'll just select our cylinder and so that is going to place our cylinder along this surface aligned with the surface normals and so our cylinder is also being placed based on the object origin so we're just going to go up and adjust our origin so this aligns with the bottom of our object like this but notice how these are currently being placed so that they follow along with this surface and that's fine we can definitely do that however what we want is we want this to face straight up and down so again we're just going to go into our advanced settings and just set our rotation so that these follow along the global z or it might be the global x for this one there we go and so notice how now these are facing straight up and down but they're being placed along this surface right here and so you can adjust the seed to adjust the randomization of where these are located as well as the number of objects things like that and so one thing i want to point out is you can come in here and turn them off inside of your display or your rendering just by clicking on these little buttons right here so this one will turn it off so they don't show up in the render this one will turn it off so it doesn't show up in your viewport which can really kind of speed up your computer if you're using more complex objects so that's from in this video leave a comment below and let me know what you thought was this helpful to you have you been using particles in order to place objects randomly inside your models just love having that conversation with you guys if you like this video please remember to click that like button down below if you're new around here remember to click that subscribe button for new blender content every week as always thank you so much for taking the time to watch this i really appreciate it and i will catch you in the next video thanks guys

Channel: The CG Essentials

Views: 67,420

Keywords: blender, blender 2.82, blender 2.8, blender modifier tutorials, blender tool tutorial, the blender essentials, the cg essentials, thecgessentials.com, justin geis, justin geis blender, blender particles, blender trees, blender particles random, blender place random, blender randomly place objects, blender scatter objects, blender scattering, blender scatter trees

Id: TWZgMg56YMQ

Length: 12min 3sec (723 seconds)

Published: Wed Aug 12 2020