Maya Paint Effects with MASH - Field of grass

okay so now we want to use paint effects to maybe cover something with grass so let's just quickly make a ground plane and give it some more a resolution maybe even a little more I'm just gonna sculpt this to have a slightly different shape okay and then I'm gonna make a little pool in the middle I'm just using the foamy brush to hold down control it will instead of adding it will subtract or push in so I can use this to make a little pool later maybe hold down shift I can just smooth seeing that turning a little bit or a my maybe I'm imagining it anyway so we have simple piece of geometry and we will delete its history for these transformations and now let's just hide this for a sec we are going to go into the content browser and here we'll grab some grass ask lump maybe and I just want to paint one little grass club okay a couple of things I'm going to change in the settings so in the brush under tubes under growth nope under behavior Oh what am I looking for oh yeah so under with scale then the tube direction is along the normal but you can see these things are have been adjusted I just want this to stand up straight everything else that's fine and again we're just going to convert this to modify convert paint effects to polygons okay that's good if I hit W now you can see that the pivot points not right in the middle so it's hit so if I press D on the keyboard I can put the in the middle at the base hit D again hold down X and snap this to the middle of the world then I'll just freeze its transformations and if I don't want the history of this attached to the original brush which I may want because of the animation I can leave history on but I don't want to so I'm just gonna delete the history edit delete by type history right so I'm gonna convert this oh no I did convert it into polygons right so now I could just use this as my mash object I could select this and go to effects mash OOP got selected mash cream ash Network instance or so on right but I'm gonna do one other step now this is in a group note I can just drag this out it doesn't really need to be in a group note before I do that I'm just going to fix the shader again let's open the hypershade so it comes with this grass clump shader I think it's just a ramp so we can just use the same ramp again we'll just use an AI standard surface and this time there's no transparency or anything I'm gonna take the a color of this ramp into the base color and I can't even just delete this one actually I just wanted to see yeah they've got some specularity and they also have translucent this is the old-fashioned Maya stuff so we could go in and change these I'm gonna turn specular down just to avoid problem you could make it subsurface let's not worry about that right now and we're gonna make thousands and thousands of these things and they all have to render separately of course so I'm gonna be careful so let's call this grass so like I said you could is that assigned no there we go let's just double check and make sure it works to have a light all right it's a pretty good set that ramp is going from the bottom of the top because the UVs are laid out it's just going from kind of greenish brownish yellowish to brighter green at the tips now like I said we can just make a mash network using that or we can use and I learned this from the Autodesk website so it's not something I invented but you can select an object like this and go to Arnold stand in and we can export this object as a stand-in getting an error for some reason just leave with a default export selection and you can see I've done this already it's a dot a SS file somebody's funny and Arnold okay now we're gonna hide this and we'll go to Arnold stand in crate stand in except I forgot to open the option box Arnold standing create stand in select the one we just made and it brings it in as a little bounding box but if we render it it's our little grass so the good thing about this is that you can populate your scene with thousands of these things and it won't slow down your machine too too much so let's get this poly plane out again and now if we select this stand in your they iced and then we can rename it and we can go to mash create mash Network make sure it's an instance err just give it linear for now we're gonna switch the distribution type to mesh and then our ground plane we can bring into our input mesh right and we can increase this value by a lot there are different ways we can put this on the surface there's a world node that would allow you to make more of a landscape distribution of these but I'm not going to look at that right now alright kind of sparse little desert so let's change it to 10,000 that's better you can see it wrenches it pretty quickly really all things considered and just like any other Arnold whoops that off-screen any other mash object we can still put in procedural notes like a random node and now this I've noticed this is a little wonky I want to rotate it about the y-axis it's not working it's kind of hard to tell no it's not you think the y-axis should be the up and down axis but I have noticed that there's some reason it doesn't give me always and up and down access that all of them are turning about a weird access it might be to freeze its transformations maybe okay that's not working for some reason but we can vary the scale a little bit into y-axis make some of them taller than others now I thought my pivot point was in the middle it is okay so even though there are 10,000 of these things it's still pretty pretty responsive and if I render it's pretty good so the scale is being varied now if you wanted to vary their color you could do that but it'd have to be a mesh node a mesh Maya up a mesh mesh which would probably increase the render time considerably this that just took 8 seconds at half HD and we can add a little bit of rotation randomness so if we go into our distribution no.2 we can tell it to use face area which will try and distribute it more evenly in this case all the faces are the same size it is filling in some of the gaps though so that's pretty good kind of some emergent patterns here which would be solved a little bit if we could rotate it a bit more we can continue we can do other things so if we wanted to affect the visibility so if we wanted a bald patch we could use it with the visibility node I should turn this off and in the visibility node we could use you know fall-off object like create that so it's only visible in there or we can invert it make a hold space like that so that's pretty handy I'm going to turn this visibility node for now I'm gonna delete this oops what do they do okay you can also affect the visibility by painting a strength map so if you painted white and black you could use that in fact you can actually you can do it either as a texture let me hide this mash or you can actually paint the vertices of this object and it's kind of a strange way to approach it but if you right click and let me just put a new material on here just put a basic lamp right on here before I click and we go to paint we can paint the mesh vertex color and so if I open up this tool we can flood it with white which means let me reset my tool here flood it with flood it with white and then we could go in and paint it with black in these areas where we don't want it to let's you appear now I have to admit I don't know why this just works and watch it probably it won't work now that I'm saying it but so I'm not painting a texture here I'm painting the vertex colors of the actual geometry and once I paint some of them black it's sort of an honor off prospect here even though we can use a smoothing brush if we wanted to kind of gray out these areas on the edge here but it seems to me that when you do this now this is not part of the shader this is will not render but if we turn that mesh back on okay it worked perfectly this time I'd noticed that when I painted this out it would not grow anything in these areas hmm well under the visibility node okay so we can paint a visibility map on here there's probably other ways to do it I think you can do it by painting vertex colors too but I haven't found it to work consistently for me so I just put a Lambert on here and if I right-click on the object go to paint 3d paint it's going to so you have to have your project set up for this to work and so I should save my file actually so so in Maya this works better if you have a Maya shader on here to show up on screen so I'm just using a Lambert and if I do 3d paint you can say attribute to paint color has to paint into a file node so you have to assign texture first give it a better resolution than that my iff let's just change that to a more common file type like a tiff okay so now it allows us to paint in here so I can paint I can flood this with white so the flood color with white and then I can paint black in this area here I know the way I turn on my great so I can see sort of where I think the ground level is I'm just holding down B to make my brush bigger okay I can flood smooth this oh no I can't do that here can I I can I can blur it I could flood that maybe I'm just gonna blur the edge though I get kind of a transition between the black and the white here let's see how this works with our distribution okay so let's save this texture and I don't need to keep this material on here in fact I'm not going to I'm going to put a new AI standard surface we're just painting that in order to get a map that matches this thing so back to the mesh if we turn this on and then we go to our visibility node strength map so now we can add a file node and load an image well it doesn't put it where you'd expect makes a new folder named based on the file name and then so there's the poly plane shape color TIFF there it is and load it up there you go so sometimes it doesn't figure this out properly so if we go back into our mash so that's the strength map in the visibility node sometimes it needs a map helper and that's where you would middle Mouse drag the polygon plane in and so that allows it to recognize the UVs on that object and know how to lay that texture out onto the surface I suppose we could all you also use the same map to make the ones around the edge a little bit smaller since I've got that gray thing painted in there so I think this could work if I just in the strength map in the random node that I have affecting this scale if I go to file and map it's in the same thing yeah so it changes so we're getting a value of one here here where it's great that I sort of death that this is going to be very noticeable but if we now go into Arnold and render anyway that looks pretty good we got our shiny ground here because our Arnold shader has high gloss where's my shader call this ground shader I don't want to be shiny and of course we can just change its color we goo but no easy texture in here so that's the Arnold noise oh no I want to make if you make the scale numbers smaller the texture itself some more spread out and I can just change these colors to a brown ish color maybe and a different brownish color just to break it up a little bit anyway that's how you can use paint effect convert to polygons switch their shader turn them into a Arnold stand in import that stand in so we get low res versions distributed through your scene and then when you render it renders at the actual object hope this helps

Channel: 3D Splanchnic

Views: 40,826

Keywords: maya, mash, paint, effects, rendering, animation, standin, grass, arnold

Id: -EpUI_H82e8

Length: 20min 10sec (1210 seconds)

Published: Fri Nov 09 2018