It Moss Be Done - Rendering Moss in RenderMan for Maya

[Music] hey y'all i'm back and today we're going to be talking all about moss i'll show you how to take an atlas sheet from quixote's mega scans of all these little moss strands how to set up the geometry and prepare for scatter and then we're going to reproduce this scene that i have up in front of me just to demonstrate the the techniques of using these atlases now all the all the assets that i've um used in this scene are from mega scan so i will leave links to all the various assets in the description below so you can actually use the exact um assets that i'm using here so to start uh before i even jump in here there's some preparation that we have to do with the atlas to to prepare these little moss strands before we get into it so i think that's where we'll start and then once we have those uh prep prepared and ready we'll jump into this scene we'll kind of figure out what's going on in here so i'm going to jump over into maya lost demo and there are a few ways that i've seen to create geometry for these kind of atlas sheets um all of them are frankly tedious and i've tried a few and i think the method that i do in maya is it certainly tedious but i feel like the meshes you have better control over the output mesh of the strands there's some alternatives in houdini and zbrush if you search around you can find those and if they suit you great but i will show you how i do it in maya so i'm going to start with and in this specific scene i've used three different types of moss for variety i'll show you how to do the setup on one specific type and then you can take it from there to do some others so i took this specific thing and again there's uh i'll leave a link in the description of which specific one this is so i'm in krixel bridge right here i found the moss that i want and i downloaded all the maps and for atlases there is no geometry associated you just get the texture maps so that's our job to create the geometry [Music] so i'm going to open up maya i'm going to create a plane scale it up a bit five rotate it um 90 degrees because we want our moss to be facing up let me go into the front view and then there's a few things that we're going to do to set this up so one thing i'm going to do is i'm going to load in a um a texture this is going to be the um the albedo of the moss that we're working with here so then i'm going to pipe it into a pxr surface as the color i'm going to apply it to this and we can see on the screen what we get here so we get all this all these little strands of moss now it's because the albedo map actually blends the colors throughout the rest of the map it's a little hard to see the borders so what i actually like to do at the start is load the opacity map and this gives you a much cleaner easier to read texture map so um what we're going to do is the end result is to have a very low subdiv you know subdiv model of each one of these strands and it's kind of it's kind of tedious so you know put on a good playlist and just kind of hammer through it but once you get it done for one atlas sheet save it off and you can reuse it again and again so it's a little time you invest in the beginning and you can uh you know pay dividends down the road so what i'm going to do here is i'm going to subdivide this a certain amount so i get kind of what i'm after here so what i like is basically three subdivisions width on the on the moss itself i want one edge going down the center that way i can do some bending of the moss and it will bend appropriately down the center and then a few subdivisions on the you know the height wise again for bending and and deforming there so if i do this 24 subdivisions on this poly plane seems like it will do what i'm after um so basically what i found to be one of the easier approaches is now i'm just going to mash the vertexes around these pieces and then cut the faces out so let's get started so if we take go into vertex mode and say i want this center line to be the center line of this moss i'm going to take this vert and stretch it over but you'll see we're actually stretching the uvs when we do that that is not what we want so to get around that you go into the tool setting so just double click on the move tool there's a preserved uvs checkbox if you click that and now we move this again you'll see that the uvs stay roughly the same yet i can still move the vertices around and the reason i do this is because we want the uvs to stay consistent i i've seen other approaches where you use a create polygon tool and kind of trace around it but then the uvs are messed up and you have to actually manually align the movies and that's no fun so anyway preserve uv's is on and i'm just going to kind of uh massage some verts around i just want a couple of subdivisions with and then a few along the height just tracing around doesn't have to be perfect but in the world of ray tracing it is more expensive to trace through a face and calculate opacity than it is obviously when you're hitting the opaque part of the texture so we want it tight like that something like this then we go to face mode and i'm going to do a mesh tools no let's edit mesh duplicate and right away i'm going to delete the history and when you do a duplicate face it creates a group underneath of the plane and then the faces i'm just going to hit shift p and that just removes it from the parent so here's our plane and then here's our little piece of algae or moss so at this point it's just rinse and repeat i mean that only took a matter of seconds to do i mean there's a lot of pieces of moss on this sheet you can choose to do all of them or some of them but it's just a kind of just hammered out it doesn't take very long and um the end result you'll get some nice realistic moss pieces that you can scatter and get really nice results so i'm just going to keep doing this i'll do a few i've gone through and done this whole sheet already so i'll just demonstrate here the approach i have so that looks good and one thing about the center line we want it to be centered with the stem of the moss again for deformation purposes we don't want it to be deforming say over here that wouldn't make any sense okay that looks good same thing duplicate delete the history shift p to unparent and then i'm actually going to start a group here with my moss so i can keep the little pieces separate and here's my plane so i'll go ahead and do a few more just for the sake of demonstration the other approaches i've seen have been more procedural but the mesh itself the resulting mesh say if you're doing the zbrush and mask on the alpha and whatnot you have kind of a messy mesh that's got to be decimated and the it may not matter but i feel like the deformations on a mesh like that aren't going to be as clean so i do prefer doing it this way again center line grab this duplicate face delete the history shift p i'm going to grab this group it and i'll do one more and we'll kind of uh leave it up to you to do what you need from there but this is rinse and repeat it's kind of rewarding at the end if you've gone through a lot of work to create an asset that's just works really well looks good scatters well i feel like it's there's a sense of almost pride in setting these things up yourself i did hear that kwixel is working on a way to provide base geometry with their atlases which is which would be great even if they're just flat and we can just kind of deform them from there that would be a huge time saver so maybe maybe this will be obsolete before we know it duplicate face delete history shift p to d you know on parents okay so here's our plane and then we have four moss pieces that we've left so you just repeat for the rest of the moss but for now i'll just show you how these will be set up here so i'm gonna go to object mode i'm going to center the pivots the pivot is very important when you're using maya's mash it uses the pivot of the geometry as the scatter point so we want the pivot to be at the base of the moss and now on some of these the base might be up here not all the way at the bottom so in order to really demonstrate what i'm talking about i am going to load the albedo back up we can see this so in this case the base is something like right in here even though the geometry goes down to this same for this it's a little higher so you think of if you're scattering it on a surface where do you want the you know the the moss to be above the surface and it's going to be here you don't want it to be like this little strand there's the surface and then the strand comes up so to change the pivot you're going to hold down the d key and then you can drag it from there as i'm holding down the d key and that's where i want there hold down the d key i want the base to be there again d key down here and i feel like this now that i have the albedo visible i can see that really this center line should probably be more aligned with the center of the moss so go back to object i i still like that pivot though and then this holding down d the base there excellent so we have four pieces of moss now if you were to go and take and scatter this scatter these pieces of moss right now it would look good but it wouldn't look great and reason being they are perfectly flat they're planar so depending on the camera angle you might not see the moss and we want to change that we want to apply some deformations so at any angle that you see it you get actual you know visibility it's not like just flat cards so to do that i'm going to take these these are very low res i'm going to actually subdivide them once just to help with the deformations subdivided so then let's take this for example and i want to actually do a band maybe a few different bands to make this non-planar so if you go up to the animation toolkit here you go deform non-linear bend that applies a deformer to that piece of geometry now by default it's not oriented correctly i want it to be lengthwise with the piece of geometry so i'm going to rotate it 90 degrees and i don't know which way in the x-axis it is so i am going to um just apply a bit of curvature and just see what's going on so we don't want it to bend this way i was i was hoping to bend it you know front or back so that means i need to rotate this handler 90 degrees one more time 90 degrees and i'm going to back off on that curvature a little bit and then for me i i want the base to be straight and then the curvature to taper toward the top and we can do that by changing the bounds so i'm going to change the high bound to something even zero i can move this down a little bit and again we can bend and curve the moss how we see fit more or less randomly we don't in no specific way it should be just something that's non-planar and that's where those extra subdivisions come into play if i hadn't have subdivided it you get a real faceted result so i do that maybe there and then i will actually do that again by hitting the g key it'll apply another bend deformer and i want one that's width width wise so i'm going to rotate it 90 degrees i feel like that's not 90. i missed it if you hold down the j key it constrains it to i think 15 degrees rotations so here's my second bend i'm going to apply a little curve there and i want it to be this way so you can kind of see what's going on it's wider than i want just kind of want it to be part of the geometry and then something like that so right away just looking at this with two ben deformers that is 100 more realistic than this for example if you were to scatter this and that now just taking a step back i'm only doing this for four pieces of moss if you pull up that sheet there's i don't know 30 40 pieces of moss on this and if you really want variety you're going to want to do this on multiple atlas sheets to get some variety of the moss applying bend deformers one by one is a very time consuming thing so i'm going to share a script with y'all i'll post it down below in the description how we can do this automatically i wrote a little python script that does just this just what i had been doing on this one so you select the geometry you want we're going to do a sideways band a length bend and a length twist and it uses some randomness to so they're not all the exact same and just kind of deforms them in ways that makes it look more realistic so i just selected those three ran the script and we see our result you know maybe maybe this one's a little bit too much curvature there i can back it off manually if i need to but in general this one's got a nice little twist to it it might even be able to do a little more twist go to the twist we can kind of finagle it from there but the whole point of this is just to make it so they're non-planar it'll scatter so much better it'll in your results will be so much more robust by doing this so again i'll share that script it's a simple python script and just grab your geometry run it and just get a little bit more realism to your pieces of geometry here so all right so we're not done quite yet in preparation so we've done some cool things we've created the geometry subdivided deformed now to prepare them for scatter i'm gonna go back to the front view i'm gonna grab my pieces of geo delete the history we don't want any of the deformers linked to it and we actually want these at the origin the zero zero origin so what i can do is with all of them selected hold down the x key and that's going to constrain my movement to the grid and drag them all to the center right 0 0. so they're all stacked and um ready to go that way now if if i were to apply a mash network to this they would scatter appropriately of course you have to freeze transforms don't want to forget that so they're zeroed out at the origin ready for scatter now one thing that you may want to do beforehand you can do this in the scene that you're using them or you can do them beforehand is set up your shader as well so then you can just have this moss ready to import into anything you want the shader is ready good to go so i just spaced them out one more time so we can actually see what the shader is going to look like so let's just view the shader so in a previous tutorial i had done mega scans to render man i showed you how to set up shaders i'm using mega scans assets so all i've done is taken the maps provided for the atlas and hooked it up into a material that we can use and if i apply that we can see it's gotten a little darker because i'm using asus in this particular example but the shady network's basic we have our albedo ambient occlusion multiplied over the albedo our opacity we have our transmit um color that is the subsurface color our specular and our roughness and our normal so i'm basically plugging it all into a pxr surface and um ready to go here so if i just do a uh viewport render for render man you can kind of see how things are looking now we see some splotchiness here and this is good that to demonstrate here that's likely a displacement bound issue but overall these are looking good so what i can do is i can grab this geometry f4 oh that's a hotkey of mine actually so this is just the attribute spreadsheet i have out keyed f4 go over to render man um i actually do want to subdivide these even more because i'm displacing but if i scroll over to there's a displacement bound i'm just going to bump this up to maybe 0.5 and you can see those holes go away we can maybe try reducing it 0.3 no still have the holes at 0.5 you want it to be as low as you as it can be but i definitely don't want any cracks or issues there so you can see with all the deformations if i scroll like to the right pan to the side here you can see they actually still hold up from the side whereas if they're a planer i wouldn't see anything at this point so this is a good way to set up your mouse in a separate scene again it's kind of tedious but once you set it up it's good to go you can use it in any scenes and having the shader all set up and ready in this is beneficial as well so i'm going to kill that viewport render i'm going to take these all back to the origin then what i would recommend doing at this point is taking the group and doing export selection just do moss export i'm going to save it to this particular asset and then i would save it as a maya binary that'll bring in your render member it'll save your render map materials along with your geometry so when you import it you're good to go you're you're hit the ground running so anyway that's how i would set those up now in this particular example i'll post again these the asset ids in the description i used three different moss sheets this was the main one that i had done i did most of the mos sheets there and actually have them in this scene so you can see here's all the ones that i had picked to do so you can see exact same process and if i go like to the side there's a there's some good variety there and if i were to again launch a render you can see they hold up very well from any angle even that so that's kind of the goal here okay so i will again i'll post the asset links here there's three sheets that i did you can pick and choose what moss fits for you there's a lot more atlases out there on mega scans that you can leverage but we'll go from there so with that uh after this cut we'll go over to maya and see what the other scene is looking like [Music] all right we're over in maya in the scene that we're going to be doing our scatter for the moss and i'll just give you a little breakdown of what's going on before we start scattering so you're a little more familiar so here's the camera angle i've chosen a very long lens to have a very tight focus on the statue here focal length of 200 and a stop of 2.8 so we're very narrow depth of field so if we come out of this we can see it's just a handful of assets very simple i again will leave a link to everything that i'm using in the description it's all quicksole assets so for example the the main assets that i'm going to be using for the scatter is the statute so if i just search for it here it's this one right here this roman statue so what i like to do in my scenes i'll pop this over real quick these are actually alembic caches not actual geometry loaded into the scene and i like to do that because i like to use the high resolution mesh from qixel one thing that you can't do is scatter mash or use mash to scatter on olympic caches so the reason i say that is when you're in bridge and you're downloading the asset and say you want to scatter some moss on this you can use the olympic cache as the rendering geometry but you're going to have to have at least the lod0 mesh as an fbx to use for the scatter i can demonstrate that what i mean here in a minute um so anyway download this high poly lod0 again for scattering purposes and these are the maps that i use for rendering the high polys the roughness normal bump specular cavity and albedo i don't need anything else so download that and along with i did some moss scatter on this back wall so if i pull up the end result there there is some moss here behind the head itself i'll leave that up to you i won't actually need to do that in this demonstration but again you'd want to download the fbx of the lod zero to scatter and then if you want the high poly source um sorry my nuke is is wigging out a little bit but i was just trying to zoom in to show you the moss on the on actual rock back here anyway so back into here so these are all just caches these are some ferns a few other plants and some of the staircase and the ground so these are literally all just straight from qixel took the textures didn't have to do anything so one thing before i get started is if we do a render i'll just run to the shot cam real quick let me make sure i'm not rendering 4k which i am which i don't need to let's go back to that 1080. so if i render shotcam we can see our starting point and everything is just straight out of mega scans except for the statue and we can see that here in a moment we'll notice that the material on the statue does not match what is in quixote this is like a more of a clean marble look i have retextured the head to have more of a like a lichen covered granite as if you'd find it in the forest so i took it into substance painter and again used a mega scan surface and just re-surfaced the asset here to make it look like it's out in the jungle and it would have moss growing on it so it just made sense so here's our starting point everything else is just stock out of quixote which is nice and my goal is to scatter more on the top and in the crevices of the of the head itself so if i pull up my main reference for this let's go over to pinterest which is always my source of inspiration it was this specific one that drew my attention statue the moss was mainly on the top of the head some on the back wall and then kind of creeping down underneath a little bit so that was just kind of my main inspiration for that so that's kind of what i'm going for here so to do that i'm gonna kill this render we're gonna do a collection of masks for our mash networks we're going to do a few different varieties of the moss that we demonstrated earlier in this video just by changing the shading so we're going to do some that's a little darker green some that's kind of the base green and some that's a little more yellow and that'll add a nice variety and look a little more realistic and then we're also going to throw in two more different kinds of moss that i mentioned earlier that i took from a different atlas sheet and just kind of sprinkle it in to again add a little bit more realism there so to start the first thing i'm going to do here is this is my olympic cache and then i have my level of detail 0 parented to it or constrained to the olympic cache so i can actually do the mos scatter on this mesh because like i said you can't scatter on an olympic cache so this is just here and hidden and i use that to drive my mash scatter and i'm rendering the high resolution high poly mesh from quixote so to do that we're going to scatter so i've i've imported so earlier we exported a maya file a maya binary of the moss already with its shader i've imported that into the scene and it's ready to go so here's all of the cards that i generated for that same atlas that we were working on earlier i'm going to select all of them individually i'm going to go over to the mash tab here i'm going to open up the mash editor and go create now actually if this is the first time you're creating a mash network you actually want to do this a different way there's two different types of mash networks one is a i guess a method of duplication or it's actually creating a duplicate mesh for every instance and there's one that's a instancer network which is what we want we want all of the moss geo cards to be instanced over the surface of the geometry it'll keep it more lightweight that way so by default it's actually a duplicative method so we need to go over to the animation toolkit mash create mash network options and by default it'll be a mesh we want to change it over to instancer so if i have all of my cards selected hit apply [Music] it will create i open up my editor again a mash network i want to rename this mash this is just going to be my base green and then i like to give a tag of what it is so this is just going to be the mega scans id that i'm getting from the geometry here [Music] and it by default creates a distribute node i want to distribute it on a mesh and then it's going to take an input mesh as the target for the scatter so for that i'm going to find my level of detail that i was demonstrating earlier middle click and drag over to that so you'll kind of see a little bit of moss sticking through and again this isn't being driven by any sort of mask or map or anything it's going to go over the entire surface if i drive this number up to say i don't know 10 000 you can see we have moss let me just focus my view here we have moss scattered on the head there's a few things here that we notice right out of the gate one they're all oriented the same and two they are all the same piece of geometry even though i have 38 cards it's only scattering one so we need to add a few more nodes here one of which is an id and i'm going to set this to random if you set it to linear it's going to cycle through one at a time the entire quantity of the scattered geo if i go random it'll randomly select from the pool of instance geo and we can see already we're getting better results orientation is all the same which you still want to fix but we're actually scattering all of the 38 cards that i have here so now we're going to add some randomness so you add a random node and by default it adds a translation randomness which i don't necessarily need but what i want to do is add a random rotation 360 degrees around the axis and then some random tilt in the other two axes just to add some realism there so for rotation y 360 degrees so it'll go be able to be positioned and scattered in any rotation around the tall axis of the of the geo and then i'm going to do something like 30 degrees in the other axis just for some tilt and this is random of course and then the scale i do like to randomize the scale sum as well just like in real life and all these pieces of mass aren't going to be the same size so i'm going to uncheck absolute scale because i want it to actually be able to scale smaller and larger if it's absolute it's only going to get larger so i'm going to turn that off and then this is the i guess the random quantity that you want to be to be able to scale the geometry i'm gonna go point four so that means it'll get point four i guess this is forty percent smaller up to forty percent bigger and uh uniform i want it to be x y and z i just want it to be as a whole i don't want it to be stretched in any one direction or another so right now we're actually looking better all these are looking fairly random we have different selections of the moss and they're all oriented differently now if we really want to demonstrate this randomness if i just do something like 10 here maybe that's a little too crazy if i do five you can see some are really small some are really big so you can get some really nice variety just by using this random note i'm gonna keep it more subtle than that i'm gonna go back down to like point four they're looking good so this is going to be the main base of my scatter now you'll notice when you're rendering you're going to need a lot more than say what i have 10 000. so we're going to do some testing with a lower quantity then when it's time to render you can you can crank it up and do some tests but the main thing here is we actually want to mask this out and constrain it to certain areas and not have it be across the entire mesh so we can do that using a visibility node so with the visibility node we have the ability to plug in a mask just a black and white map that will tell the mash network where to leave the scatter and where to i guess hide the scatter um so what we're going to do is at this point we need to actually create a mask we don't have anything like that to drive off of so my preferred method is i've taken the geometry and i have imported it over into substance painter to export a few different masks to use for this purpose so i'm going to open up substance so here's my base color like i was demonstrating and i have some masks that i've created up up here for the different scatters so really all i want is a black and white mask to drive the mesh so i'm going to start from the bottom here so here's my main mask that i'd like to drive the the overall i guess the the highest amount of the scatter it mainly from the top a little bit on the bottom definitely in the crevices and you can do this all in maya with different noise and and textures and um various ways i find doing it in substance is easier and quicker so after i do this i've created just using an mg mass builder a mask that i like then you can right click export mask to file so you can export this now i've done this a few different times because we're going to do a few different scatters and it's as easy as just creating different splotches and patterns and variety to emulate the randomness of nature and do some different areas for the scatter to be so i'm just kind of clicking through some of the mass that i've created in substance again this is the main one that we're going to drive off of and so on and so forth so play around create a mask right click export mask to file and we can use that in maya so over in maya if i open up the let's see i need to open up the hypershade let it load up for a moment i have a helper map tab here here are the five masks that i just showed you in substance that i've loaded in so just load them in as normal maya file textures mash does not like pxr textures so we need to keep it the file texture so the main one head moss mask this is the first one that i showed you um it's just the basically the top of the head so what we can do we actually want this to be wrong so go open up the visibility node of your mash network sometimes you have to toggle back and forth because mash is a little bit buggy so we're back in the visibility so we need two things we need a map helper this tells the mash network how to apply this texture that we're going to be plugging in so in this case i'm going to drag the lod0 mesh it's going to automatically go uv to text that has uvs and now i'm going to middle click and drag the strength map of the mask that i exported from substance so now it takes a second we should see that we don't have very much moss on there right now to really demonstrate but we can see if i turn this off it's down here underneath where we don't want it if i turn it on it's constrained to the top now if i crank up the amount of points like a lot 100 000 you'll see a better effect of what i'm talking about so you'll see it is constrained to the mask that i exported from substance painter so you'll see even in my viewport at 100 100k nodes it's getting a little sluggish so i do some tests i see it doesn't look good and then i back down the amount of points just you know for performance reasons so actually let's do a quick test render at 100k and see where we're at at this point okay let's open this up looking pretty good got some moss it's looking good now i can tell we need a lot more of it but in general it looks good so far one thing you'll notice as well is the lack of variety i know we've just done one scatter at this point but you can really tell that it's all the same moss all the same texture so that's why we do multiple scatters to blend in some different shading varieties and some different moss types so anyway we're looking good i would recommend at least five times what we have here so i'm going to cancel this i don't like to ma muck with mash settings um live on an ipr doesn't handle well typically so i'm gonna up the amount and then kick off another render and see what we get all right so i i upped the amount on the distribute note to 600k and we're getting a much nicer result than at 100 you can see the difference i didn't change anything else with the mask i just upped the amount so it is a little surprising how much you need but when you're doing such fine detail like little individual strands of moss it's you need that extra detail to fill it out so 100k 600k sweet this looks really good already just one single atlas sheet with one material and this is our result so i'm going to go through and do a few more scatters based off the different masks that i had in substance painter to get some variety so i'm going to cancel this render i'm going to take this back down to something reasonable actually i'm just going to hide this so what i like to do when i'm doing multiple scatter is once i'm happy with something hide it and get it out of the way so it doesn't impact my performance so i've got some layers i already created that i'm just going to add this instancer to this layer rea dl2 again that's just the id from from qixel and it's gonna chug for a little bit okay and it's hidden so it's there and when i want to render i just hit re-enable this layer hide these ones as well and that's out of the way perfect so we're going to do that this whole process again so to add variety here so what i've done is i have you'll notice these three moss rea dl2 that's the id i have three uh copies or two copies of the original and i also have copies of the original shader so you have i have three of the exact same shader that i've copied and then what i've ended up doing like for example on the yellow version in the albedo color correct i've changed the saturation on the green one uh i've changed the hue a little bit and then i have a darker one even i go in in the albedo i change the hue even more as well as the transmit color i just add some variety and on this one the dark as well i've added a pxr very to the albedo with a very small amount of hue variety just to again add a little bit more realism there so i have three copies of the geo three copies of the shader i'm gonna do three different mash scatters for each of those with different masks to add some variety so let's do it so i'm going to do the yellow i'm going to grab all of this create mash network and after you've done and created an instance or mash network from the settings it will stick so now i can just go create it'll be an instancer by default yellow cool mesh again i'm going to drag the statuette there i'm going to start at 10 000 just to see what's going on uh id node and realistically you could probably copy paste the previous network and just change the distribute geometry or the instancer but this doesn't take very long to go through and do anyway do a random pretty much the exact same so 30 degree tilt 360 degree rotation 30 degree tilt and then a 0.4 uniform scale variety there cool and then a visibility node well the cool thing about the visibility node that i'm not using in this case because almost the entire statue is in the camera frustum as you can call scattered points based off the frustum of the camera so for example if i have a field and lots of grass the visibility node has the ability with frustum filtering to delete everything outside the camera frustum so a little tip there i'm not using it in this case but something to keep in mind all right i'm driving dragging the statue there and now the other mask the yellow is this guy so a little more splotchy i think what i ended up doing here is using the exact same mask as the green but then i've multiplied over a black and white clouds layer so it's just kind of intertwined in the other mask so with the yellow let's go there again this should be raw okay all right and again i just think we'll likely need a lot more let me crank this so this is 10k let's go 400k all right so we can see kind of that splotchiness there so if i i'll go ahead and do the other scatter before running a test render but we can see that this is gonna add some nice variety so same with this i'm going to add this new scatter instancer yellow to my layer just to hide it as i work on the other ones now one thing i do want to point out is on the distribute mode down in the advanced there's a batch render multiplier so this will like it sounds multiply the the number of points when you're doing a batch render so you can interactively test with much fewer points for performance and then set this to something like 10 or 100 depending on how much you've reduced it interactively and it will apply the those number of points to a batch render so keep that in mind that that option is there interactively i like to see what's going on and then once i'm iterating say i'm iterating on the stairs or the back and i don't want the you know the the weight of all of this mesh when i'm not iterating on it i can set this batch multiplier so that's there all right we're going to continue on here a few more scatters we're going to do a dark scatter has more of a dark green hue to it and this is going to be literally the same thing so mesh scatter on that let's start with 10 000 just to see what's going on id random random all right and one thing to know about this i intended for the dark ones to be darker green a little more i guess healthy living so i took the base geo of the scatter and i have scaled it up by two so it's actually going to be twice as big as the other scatter so it'll actually stick out a little bit as well just the all the more variety you can add to add the realism all right so we need one more thing we need the visibility mask helper all right and then the map we're using for this it's going to be this one which is again just built on the base mask then i've multiplied some clouds with some more clouds and then i've boosted it with the levels just to kind of get some more contrast so this is the mask for that and that is the most dark that one okay hit that save button right one so one thing we can also do here is in the color balance you can add exposure to it here so say out of substance or whatever it just isn't contrasty enough or it's not bright enough you can boost this exposure up to reveal more of that mask so i just have it set at one here okay so that's looking good again just need more of it so i think for this 300 000 and these are numbers that i had to finesse and play with and find a balance for my previous tests start small and increase as needed of course okay so that looks good so right from there i'm going to enable the others i'm going to run a test so i'm going to add this to my layer again so it's going to disappear and i'm going to enable the layer and run a test okay this is going to take a moment because we have you know one and a half million points here so i'm just going to pause for a sec okay we're back so all of the mass is loaded on here i'm going to start a render and despite being instances it still really bogs down my having this much so you just have to work smart so i'm gonna kick off a render just to see where we're at i'm going to pause it all right we're back i've sent off a render come back with a few iterations and already i can see the variety here so if i go back this is what we had before which is the base scatter and this is what we have now so if i just toggle back and forth you can see huge huge difference so we have these yellow areas kind of where the moss may have dried up up through here down and around here and then we have these darker green areas where it's actually a little bit bigger um where maybe the moss is a little more healthy it contains more water so it's huge huge difference i mean this this alone looked pretty pretty decent adding this is another level now i have it a few more moss varieties that i could throw in and scatter for a little bit more and i'm going to do that it's the same exact process so i'm just going to pause it and come back with another render and see where we're at at that point all right we're back i added two more mesh scattering networks for two different mosh atlases very scarcely so just to revise the mask that i used were just a few kind of spots different spotty ones just i wanted it very scarce and you can see they're a little darker i have some red in them so if i go back and forth this was the render before this is after you can just kind of see some variety and i think if you study reference you'll notice that's the biggest thing is it's just there's so much variety in this kind of thing so you can keep going and going and going and adding more and more different types and i think you probably i mean the more the better but anyway that's i think where we'll stop with the head i'm very happy with that i think um a total of five mash networks three using the same exact geometry and then two just very sparse accessory ones now in kilt this render now in the final image that i had again i had some moss scattered on the rock behind it so it's the same exact process and my nuke is struggling right now basically what i did i can demonstrate that is i'm going to open up the um rock face i believe so this is what i did so i exported the level of the lod 0 for the rock face and the led 0 for the statue head into substance so i can do this ambient occlusion kind of area right here so again i noticed in my reference on the contact point of the statue there was some moss growing there so that's kind of what i was sort of going to emulate so if i hide that we can see this is our contact point and all i did basically was take a brush and do some painting in here with the ambient occlusion kind of to simulate that so exported that as a mask and imported that the same exact way same setup for the mash network and just use that to drive the scatter i guess one thing to note with that i'm gonna hide some of this these are this is the two accessory scatters that i just did um so you can see how scarce they are but they do i think make a nice difference so one thing to point out here is this is a kind of a large asset so to scatter the way the mash networks work if i open this back up you're distributing over the entire mesh and then only at the end are you hiding parts of that via a mask so if you consider something like this a whole piece of geometry where i only want some um i only want some moss right here the density of those points it would have to be absurd like a million or more to cover the entire rock face and then just mask out this little part honestly it's it's to me a flaw in mat in how the mash system works so what i ended up doing is i took the lod0 mesh and i deleted everything except this little part i probably could have trimmed it even more and that way the density of the mash network can be reduced greatly the the point density and then the moss appears right here so i'm not going to demonstrate that it's the same exact mash network just plug in the mask for that okay so that's that and then just i guess the quick final composite here i did a fog layer as usual and i think this is something that is invaluable in all aspects of cg is just have some sort of atmosphere some sort of fog again this isn't the basis of this tutorial here but set up a fog layer and looks like this apologies for the incredible slowness here but the so here's my fog just a little bit doesn't have to be much and i i colored it i um grated it kind of blue and mask it over so here's the raw here's the fog and then i do a little chromatic cataboration and vignette and there's our final piece so i think in a relatively short amount i guess the the most time consuming part of this whole thing is just gathering the geometry for the the moss atlases but once you've done it once you've done it so now if i want to do another scene with moss that's already done i can just do the mash networks and it's it's great that way so anyway um i think that's all i'm going to cover thank you for following along and of course if you enjoyed this if you learned from it hit the like button it helps us out and if you have any questions concerns suggestions or just want to say what's up hit me up in the comments section below again happy rendering talk to you next time [Music]

Channel: Jeremy Heintz

Views: 4,593

Keywords: Quixel, megascans, Renderman, Pixar, Maya, moss, Nuke, Rendering, Lighting, MASH, Atlas, Scatter, Cg, 3d, 3dart, Substance, Compositing, Python

Id: HMwKE-vuLVc

Length: 61min 0sec (3660 seconds)

Published: Sat Mar 06 2021