Relief Shading in Blender - Tips and Tricks with Peter Atwood

[Music] hello everyone uh thank you so much for uh joining me this afternoon my name is peter atwood and i'm coming to you from uh halifax nova scotia where it's lovely and sunny today after a very late snowfall yesterday um so first of all a big thanks to daniel huffman for organizing all of this this has just been a fantastic resource and a great learning opportunity um and what i'm going to be doing uh is just taking a quick look at sort of how i go about shading relief maps in blender i've found it's been a really useful tool for me i've used it a bit in the past for doing animation and since sort of starting to explore map making a little bit more i've also found it a really uh really fun a really interesting tool to use and a great way to get um to create sort of tactile uh sort of text uh textural maps um so how i think i'm going to uh go about this is i've got a um i've got a relief map that i've set up sort of following along with uh daniel's tutorial uh from his blog and that's that's a great starting off point i've put a link to it in the description in the description of the stream um i've also put a link to a write-up that owen powell did uh also a good good good starting off point in something and something that i've learned a lot from um and then i'm just going to take a look at a couple of different uh tricks and approaches that i use to color and bring some and uh liven up them liven up these maps a bit uh the other thing i'm going to do i put a link to the uh a google drive folder with this blend file in the description um sometimes i find it can be helpful to just like pick something apart and see how it works so that's available to download um for anyone who for anyone who would like to use that um all right so uh what i'm looking so what we're looking at here is uh kyushu island in the south of japan and a couple of things just with the setup i have here um so this is the uh rendered view which you can see up with a little shaded sphere in the top right corner um and this sort of this gives a preview of how it will appear when we render it out the other view the other view mode that i like to have set up is up here where we have viewport shading and if we click on this um we see it's a we got a very sort of detailed preview of how it will appear this is using blender's real-time ev renderer which is much faster but it doesn't get it doesn't create doesn't give us as accurate uh lighting that we would get through from the render preview which is which uses cycles which is a ray tracing render engine the other issue with this preview is that as you can see if we pan the camera down it's not actually deforming the train we don't actually have 3d terrain it's simulating the effect with a bump map whereas if we go to the actual rendered preview and look down on it now we can see the sort of the texture and the elevation elevation of the map but to just get a really quick preview and sort of see our changes live as they happen uh this um viewport shading is viewport shading is great and recently been significantly improved in the past few updates um the only uh thing to note of is if we go down into the viewport shading settings we want to make sure that scene lights and scene world are ticked uh so that means that our lighting's set up uh in our scene so right here i've got a sun lamp just above our plane that that will be accurately reflected in our preview otherwise it just uses a default sort of uh studio lighting setup uh so what i've got i'm gonna split my workspace in half and over here i'm going i'm going to leave my relief map up and on the other side i'm going to switch it to our shader editor which is where we can see all the how the how the materials are set up and i've got a handful of different materials just using uh sort of showing different ways that i can color the terrain i've got the materials set up and i think i'll just go through them and kind of uh pick them apart see how they see how they work and see how we can combine them to create different effects um so with just this uh this very basic one over here we've got our terrain displacement so we're working with a dem a height map that's plugged into a displacement node which in turn is plugged into this displacement input in our material and then over here to give it the color and and all the different uh properties of the material i'm using a principled shader instead of a diffuse shader because the principled one gives us all these other options uh which looks kind of scary but but we don't really use most of them but it gives us some fun options that i'll get into in a little bit um the only thing to sort of note is that we want to make sure that roughness is turned all the way up so that way we'll have a completely diffuse surface um and i'm gonna i'll uh try and keep an eye on the um live chat but uh sorry if i'm sorry if i miss anyone on as i go through um so the first thing that we might want to do is tint our relief based on the elevation so for that go to this first one um so here's the uh here's the whole thing um over here we've got our displacement which is giving us the texture um which will stay which will stay pretty consistent throughout uh we have our principled shader and then we've got a couple of other sections over here the first one is i want to mask out the ocean so i want it to be a different color from a different color from the land so for that i'm going to divide this up once more just briefly and go to the image editor so here i can see all the images that are part of this project um the one i want to look for here if i can find it uh so this one so i just have a few like really simple masks with transparent backgrounds and i can use that to drive um where different where different effects and where different colors appear on the map so this one is just to separate the land from the ocean so to do that we have it as an image as an image texture and over here we have a mix node which lets us mix two images or if there isn't an image plugged in it just lets us use a color um so we plug the alpha channel into the factor input which determines how it gets mixed and color to color and now we have we've separated separated out the land from the ocean and then uh over here which is where we're deciding how what how we want to uh how we want to visualize the elevation we've got our dem and then the color of the dem is plugged into a color ramp and now we're just go and i've got a few different color ramps set up to try to sort of try different try different effects out and it's going to map the pixel value of our pixel value of our dem into these color ramps so we just need to plug this into the other color slot in our mix node and so with this this one it's just uh quite subtle but it really sort of helps to highlight the highlight the elevation difference in uh in the map um we can also do try a more sort of natural looking color scheme where we've got green and the low-lying areas turning into red and white as we get higher up or something more involved this one i used a color ramp from there's a blender gis plug-in i haven't done too much with it it seems really interesting uh but it's got a few um a few a few color ramps built in that's uh we can get some nice effects with that and actually i'll just get rid of the grid lines overhead here um and one of the things i like about blender is just sort of the immediate feedback you get uh so i can add more color add other colors in and just immediately see how it uh how the how the material responds um so with this so we've got we've got our uh we have our elevation visualized what if we want to visualize slope um so that's a little bit trickier but not uh not especially so for this one again we have our displacement set up and then over here to get the slope i've plugged my height map into a bump node and what that's doing is it's creating sort of an extra layer of data for every for every point in our map um it's basically it's sort of the same thing as what's going on uh with our displacement it's visualizing how light would reflect off the surface without actually deforming the terrain and it does that by assigning uh by assigning a uh a vector value a three dimensional vector value to each point which has an x y and z value and the z value of that vector we can use to visualize slope so uh i've plugged my height map into a bump node a bump node into this separate xyz node and then the z value goes into the goes into the color ramp so now we're now we can now we can sort of now we can visualize just that z just that z value which corresponds to slope so when we plug that into the color now we can see that oops uh areas with a higher slope are have a lower value on the color ramp um you could also uh yeah so and um so the next step after that might be to combine the two to combine both sort of elevation and slope to sort of highlight to highlight specific areas um oh and also something sometimes it's nice to sort of switch back to the render preview to get a better idea of what the um what it'll look like in the final render with the sort of more accurate lighting conditions um so if we wanted to combine both elevation envelope i think there's a better way to do this than what i'm do than the way i've been doing it i haven't quite figured it out if anyone has any ideas i would definitely love to hear them um once again we've got displacement same as before uh we've got our uh ocean mask uh over here and then we've got our height map going into the bump to create like a gradient for the slope and then for the elevation color i've got two color ramps and what these represent one is going to appear on areas with a very high slope and one is going to appear on areas of the map with a lower slope so sort of like um this would be the underlying terrain and this would be anything covering the surface so like vegetation or snow in the higher areas and using the uh using the slope value as a factor to uh uh uh use it using the using the um slope value as a factor to as a factor to mix them that will uh will be will be able to uh see one color ramp in areas with with high slope and one color ramp in areas with low slope so uh once i plug all those in uh now you can see we've got zooming in this this really sort of highlights where we have these little ravines uh coming off of the crater of the volcano in the center of the island uh you can see the edges uh get a lot are a lot more highlighted because we're seeing the high slope color scheme as opposed to the low slope one and again we can uh if i don't like how it's um how the how they're mixed i can adjust it through this uh through this color ramp so if i think that if i want more of the like uh more of the low gradient um effect effect to come through uh the one oh one other thing i should mention um with most of these color ramps by default it's gets set to uh ease for how it um and for how it uh interpolates between stops um i find b-spline gets uh b-spline gets a nicer sort of smoother uh gradient um moving along the next so the next thing i might want to do is to give get a little bit more visual variety to blend in some uh some other imagery um oh someone asked is there any way to render just the land area for example uh yes um if sort of if you want it transparent for the rest of it except just for the land i've got that in just a minute um but if i wanted to add some imagery to it just to get a little bit more variety as opposed to as opposed to just what we get with the procedural material for this one again it's more or less the same for uh for the displacement and the mask um and then all i'm doing is i have two uh two images one is a landsat uh tree canopy um raster and then the other is an ortho image of an ortho image of the island and then i'm just using these mix nodes to blend those into the uh to blend those into the relief that i already have now um and then also when we have the mix nodes you can choose all the usual suspects are here for blending modes that you'd find in like photoshop so i haven't experimented with them too much but definitely lots of uh potential there so we can blend in our uh foliage and then blend in just a little bit of the ortho imagery take it up to like 0.4 so that now we get a little bit of the detail and the built-up low-lying areas um but we still get the we can still really see the see the train and then because i find sometimes uh ortho imagery just it's a little bit too noisy um so this way we still get that clarity but then like a little bit of visual variety in built up areas um and so i just have a couple more um tricks that i've found uh one might be if i want to sort of highlight an area of interest within a map um what i've done with this so we're starting like kind sort of uh oh we're start sort of start with a blank map just with our water mask again but our displacements uh gotten a little bit more complicated over here i've got my elevation map and it splits uh and it splits and then goes into a mix shader one half goes straight into the mix and then the other half goes into this math node which is set to multiply so this node will take the input it'll take the pixel value of our height map perform this operation on it and then output the result uh so i'm i've multiplied it by 0.2 and then i'm using another mask to choose where the sort of dampened height map appears and where the full scale one appears so again we'll pull that into the uh height node of our displacement shader and now we can see that this section sort of pops up and it has a much more exaggerated uh has a has a much more uh exaggerated relief uh and then over here we're doing exactly the same thing we did before we have our uh our tree canopy imagery and our ortho imagery and then we're using the same area of interest to mask out mask out the rest of the map so it only appears within our area of interest so and actually one other thing i put together here just a quick example doing a little bit of labeling uh within blender i've got the uh names of the the names of the prefectures set up here and doing it with doing it within blender get some we can get some nice uh some nice shadows it doesn't really show up with the the lighting setup that i have here and how this works uh someone asked about sort of having everything except the land be transparent that's one of the reasons i like using a principled shader because uh what i can do is i have this as another mask where it's just white text on a transparent background and we take the alpha channel there plug it into the alpha input of the principal shader and now everything else is transparent except for our labels um and finally one last uh example of this uh so once again i've got my um my area of interest and this time that's interesting uh okay that's i'm not quite sure oh oh i know what i know what happened i changed that to the uh to the label not the yep okay okay there we go um so yeah so now i've got the uh the border mask uh plugged into the alpha channel of the principled shader so now we've got a uh we've got a transparent backdrop we can just see the land we have our area of interest with the exaggerated relief and then what i wanted to do with this one is just sort of see how we can use the uh some of these other settings within the principle shader and just like blender's strength is being able to like uh visualize prop like different material properties um so what i have here is again our area of interest mask uh this time plugged into three different mix shaders uh they're each going to change a property of the material so the first one is color so for this everything within the area of interest will be gold everything outside will be black and uh if we plug that in we can see oh and for this one uh i've added labels to the area to the area of interest mask and the borders between the prefectures as well um for this second one called metalness so we've got the metallic uh the metallic setting and every material as far as rendering is concerned is either zero or one it's either not a metal or it's a metal and so for that we've got one set to black one set to white so everything within the area of interest is a metal everything outside will be treated as non-metal and plug that into we plug that into the metallic and it doesn't look like much and that's because we have a roughness set all the way up so it's very diffuse but if we use the second mix one to change the roughness based on whether or not it's inside the area of interest so now everything outside the area of interest will be still be very diffuse but everything within the area of interest will be a little bit glossier uh let me plug that in and we get this really cool sort of embossed gold leaf kind of look i don't know how like there are not not a ton of cases where this would be entirely useful but it looks really neat and i think it's a really it's a great example of sort of using blender to its strengths as a way of like being able to like visualize different materials um and then we can go back to the uh to our render preview and get a look at uh at uh sort of how how the light how the light plays off the different materials and actually if we move the camera around a bit too we can see how it's how the light's reflecting off the glossier area of interest um and so i've just got a couple of minutes left um sort of wrapping up the last thing that i think i can i'll touch on very briefly i'm gonna go back to my base uh bass relief without any changes and that's how changing the lighting of the scene can also dramatically affect the effect the final the final result um because and that's that's sort of another strength strength of blender is being able to have a lot of control over over lighting and over environment um so for this scene i've got a sun lamp coming in at what is it uh 315 degrees at a 45 degree elevation and then if we go to our sun settings uh in the properties panel here we can change the strength and actually this will look better if we go back to the um rendered preview we can change the strength we can change how bright it is we can change the color which has uh which will have a dramatic effect and then angle which is sort of how large it how large the light source is in the sky um if we take the angle down really low to like one degree you can we can see that the shadows suddenly get a lot more stark and a lot more uh a lot more defined so depending on what you're going for it can be uh you might want softer shadows or you might want sharper shadows and then the last thing is if we go into the world properties panel our scenes being lit by the sun but it's also being lit by basically the dome of the sky over the scene uh it's uh invite it's being lit by its environment so right now we have uh sort of a gray light and if we adjust the strength of it if we turn the strength down to zero we can see already that the shadows are a lot there's a lot more contrast and that's because they aren't being illuminated by their environment they're only being illuminated by our sun lamp so one thing that i like to do change the background lighting to the blue and make it a little brighter and that might be a bit too much but now you get if you look at um like a photo from the international space station you can see that the shadows aren't the shadows have this bluish tint from the from this atmospheric scattering um let's see uh from from this from the atmospheric scattering so you get the sort of more realistic uh look to the relief and as a last example uh i could take i can take my sun lamp i can make it sort of more of an orange and maybe nope uh let's see bring it a bit lower to the horizon say 55 degrees and then change the color to a really dark purple and you get this nice sort of sunset sunset look where uh the scenes being scenes being lit by this very orange sun and they get a nice sort of purple purple shadows from the sky and there's just there's a ton of potential for uh for illuminating scenes you could try um i was watching uh john nelson's uh tutorial on doing uh multi-directional hill shades so i tried uh just for the heck of it to see what that might look like um i it's uh there's definitely i would definitely play with this a bit more to get something that isn't quite as loud but it's a neat sort of uh proof of concept um so that pretty much brings me to the end of uh what i wanted to talk about i'm thank you uh uh thank you all so much for uh for tuning in for listening um the i'll make sure that the stream is available uh on this channel at this url if you want to go back and watch anything again i've got a link to this file to this blender file in the description of the video um if someone downloads it it should work i haven't actually tested it yet but it should have all the masks and imagery uh bundled it bundled into it so if you want to play around with that as well and then uh i didn't really get a chance to look through the um uh to look through the live chat as much as i wanted to but i'll uh uh skip back through there and uh read through everything so again thank you so much uh thanks again to daniel for putting all this together i'm really looking forward to checking out the rest of the sessions and um if uh if there's interest i might do a little bit more of this either as like uh do some more blog posts or live streams but again thank you and have a good one you

Channel: Project Geospatial

Views: 4,232

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Id: AGczLhQg8yI

Length: 40min 12sec (2412 seconds)

Published: Mon May 04 2020