Welcome to illusion of detail using bump maps in this video you will use a text to control how light
is interacting with a surface.
We'll see how to use texture as a bump map him blend render and use generated textures rather than hamade
just to speed the process up.
If you want more control of course you can make the texture by hand.
So before we hop in a blender Let's have a quick overview of bump maps in general.
Now normal and height or displacement maps are both types of bump map the term but maps often thrown
about.
But it does in Corpus.
Both of those because they both change how light interacts with a surface.
We're going to use a displacement map in this particular example.
We'll move onto normal maps later on.
Now what they do is they tell a shader how to interact with light so as a light ray goes across a completely
blank surface.
It usually just bounces off in a certain way.
However what we can do is use a texture and this can give the illusion of detail on a surface.
It fakes highs and lows so we get some detail on our surface.
They can increase render speeds versus using geometry alone and not only that they can speed up construction
speeds as you'll see in a few moments.
There's absolutely no way that without using a texture would ever be able to make a brick look a bit
more brick like.
So let's have a quick look at hite's Maps vs. a normal map and see the difference.
Here we have a very simple jagged surface.
And as you can see the low points of the surface is dark and the high point is white and you can see
there that they drift from one level to a mid grey then to a black again and then to wide as it reaches
the highest point down to mid grey and up again.
Now that is showing the height differences not necessarily the direction of the faces.
With a normal map they don't display any height information.
They simply show the direction that the faces when we fake them would be facing so we can see here that
despite the fact that the faces themselves are higher up there's no change in the normal direction of
that particular face.
And of course we'll cover normal maps in a bit.
So let's go play with displacement maps now or height maps over and blend up.
Okay so we're back over in blender and I'm going to apply these bump maps.
This displacement map to my wall piece.
First of all for testing and I just want to show you here.
The textures does look slightly different.
I went in and spent about another half hour 45 minutes or so just adding a bit more detail to my my
base colour there and I think that's turned out rather well.
It's obviously not super detailed but I like the way it's come out.
Am I am going to switch to blend render.
Must blend again blend a render.
Okay I'm just going to sort out my windows here so we can see what's going on.
On a turn on rendered mode in the viewport shading and we don't see anything and the reason we don't
see anything is because we are still using the node setups on so and toggle that of course you can use
nodes for Blender and I've just elected not to so I can switch between these two setups to move across
to the texture's tab and add in a new texture.
Now we have a list of textures at the top here in blender render which we can use within our model and
for the moment what I'm going to do is go down to the next text just slots.
And add a new texture.
I will change the type of texture to something I'm going to choose.
Clouds I think that's going to work out pretty well.
We can see over in the viewport.
It's gone a bit odd and I'll explain what's happening there in a moment and this texture here is not
very well named so I'm going to call that displacement.
All very badly displacement.
There you go.
And this one here I'm going to call block work not block block work but just block work.
Okay so we've got this texture underneath this one and it does work in is it the order here does matter
it does work its way down so if something is.
Here in the second position.
If we move it to the first position we can see it's overwritten with block work.
If we can't see this other texture and that's because both of these are trying to control the colour
they're trying to influence the colour.
If I scroll down here until we get to where it says influence we can see that they're both trying to
control the colour and in this case the texture itself the black and white texture is saying where it
is black.
I don't want it to control any of the colour and where it is white.
I would like it to control the colour based upon this colour down here so if I changed this to blue
it'll be the cream and blue if I change it's any other colour it will be there.
Green and cream.
Now I don't want those clouds to control the colour.
I would rather they controlled something else and I can have them control the secularity and if I turn
the intensity down a little.
Let's go for point eight let's say.
Now when I move around you can see that this particular wall piece is reflective in certain places and
not in others.
And that's to do you do with that texture it's saying where there is reflection and where there is not
reflection.
Now since we're working with displacement maps you may think that's the right one to pick here.
Under geometry is displace.
You've probably been reading down here.
Gone are about to click on displays.
Well let's do it and we can see there.
It doesn't do anything.
The reason for that is for in order for a displacement map to actually display something it has to have
something to splice.
Now that does sound like a tongue twister that basically there's not enough geometry in this model currently
for anything to be moved about.
I would actually discuss actually using textures to control geometry later on not in this particular
section.
This is all about the illusion of detail not creating detail so I will want to put a tick in the normal
box.
Now even though that black and white image isn't a normal image blender render can work with it.
And here we see that we end up with a bumpy surface based upon those clouds that it's generated over
going too far we see that it's it's not perfect.
We see the squares going on here of the pixel changes so we might require something a bit more high
rez at some point but for this stage it's absolutely fine.
Now we control the normal amounts.
Obviously if we bump up the maximum five it looks really really bumpy.
Now that is no good for a wall but that might be good for some muddy floor or something along those
lines that has a lot of bumps ridges in it.
If we set it to something like point five then we get a much more subtle effect.
If we decide to go negative it simply inverts the colours so the highs become lows and the lows become
highs.
Now that is going to produce a different pattern to this.
If I whack it all the way back up again.
But essentially it is the same pattern just where it's fakin going in and out.
Now one thing to bear in mind with the illusion of detail is where it breaks down is the edges.
If I rotate this round and see that there aren't any bumps there are no bumps in this model at all.
And that's where this illusion can break down especially around the edges.
So that's something to bear in mind.
Now I've been playing with this.
And I think a normal value of point five is actually about right and that comes out pretty good.
And there we go the displacement maps in a nut shell using Benda render.
And I have got a challenge for you guys.
I would like you to create a cycles based bump map so render yourself a nice example of the blender
and a set up and use it as reference material.
See you've got some guidance to how you want the new cycle's render to look like.
Use a bump node to control your diffuse shaders normal impact.
Experiment with the nodes to get a similar appearance.
Now do bear in mind there is no correct method.
So remember there is no right way of doing this.
There will be multiple solutions however you can use a minimum of two nodes a generated textured node
and a bump node.
In order to do this.
Being creative can end up with awesome results.
Sometimes the unexpected can end up being better than what you planned.
So remember to play around with these settings and remember to think through your nodes logically at
the end.
I'll go through some alternatives and the pros and cons of using those as well.
Couple of hints for you.
There is no cloud texture in cycle so you're going to have to use something else and there is lots of
choice.
And I'd like you to plug the texture into the diffuse colour inputs to see what it looks like.
You don't have to do that but it's a great idea to get an understanding of how that texture that you're
using to control actually looks so you can just plug it into the colour input of the few shader and
see what it looks like and then you can replug everything Backhouse in as well.
Pause video now and give that a go.
Okay so let's go ahead and set up this in cycles so I'm going to go to my materials and enable nodes
and switch over to cycles render.
Now I'm not going to have my reference image on the screen because I've got it quite busy as it is at
the moment.
I'm just going to try and create myself a little more space on here.
And well this is one of these examples where a floor would be quite useful on our model so we can see
it a bit more in situ.
So I am literally I hope that's on the ground.
I'm going to go into object mode create a circle.
Just for it to exist on and scale that up or it's way over there that's not gonna work quite as I expected
it to.
Let's just add another circle and delete the other circle in a moment.
Too many circles.
Now can I add a circle.
Scale that up.
Well that's an invisible circle at the moment.
It's kind of cool Why is that invisible.
That's very good question because it's not filled.
There we go.
So that's roughly on the base of this.
Just to give it a bit of presence and I'm going to make I am going to make that in fact slightly glossy.
I'm going to go for glossy So it looks like it's reflecting and increase the roughness.
So a rough glossy material that's looking good.
This sun isn't looking particularly bright is a sunlamp the strength to turn up a little.
Okay so now we need to set this up in cycles which of course will be slightly different.
So first of all let's switch across to cycles and make sure we're now using nodes for our material use
nodes.
There we go.
So we've got our base to fuse texture back again.
Now I've got a reference image off to one side that can't for everything on my screen Unfortunately
if I bring everything on here I'll just get confusing.
So I need to modify this.
Let's zoom in a little and see how this is laid out so the output is what we're seeing.
And we've got a diffuse shader based on here and the colour is being controlled from that image.
Great.
So that's.
But that bit's set up so we need a nother texture to use for control.
So we need to go ahead and add in texture.
Now if I had an image texture that was appropriate I could use that.
That's no problem at all.
I can pick one of his other textures unfortunately clouds isn't there.
So we're going to have to play with a couple of these and see what we get so I'm going oh I've just
slipped off the menu there.
I'm going to.
First of all start with all brick texture.
Does that work.
So I'm going to plug in the colour to the few shader and just see what happens when I try this.
Well it doesn't seem to be producing any sort of textures at the moment.
Anyway I don't think that one's going to help us.
It might do actually if we have the vector plugged in so none of these at the moment are being told
none of these textures are being told how they are to be mapped so let's go and add in an input texture
coordinate and say you are being matched with unique award let's say let's map in the spirit texture
and see what happens.
Oh okay that's that's interesting.
That may that may help us.
I'm not sure I think I'd have to match up the two blocks really well in order to hear that.
But I don't think in this case that's going to help.
If we had an already blank wall that might actually be helpful if we wanted those Square style bricks.
I don't I want my other one.
So let's find a different texture.
So let's go ahead and add in texture.
I'm going to try.
Noise.
So the vector that's been mapped out via u v and the colour.
That's plug colour into colour.
Okay so this one's got colour noise and it lets let's plug in the factor into colour.
Theirs are black and white channel brilliant.
So now we can go ahead and using the colour the original diffuse texture as the diffuse colour.
And let's see what happens if we plug factor into normal.
No that's not done what we want to so let's pull that out again.
By the way when you're doing this there is a preview over in the materials side as well so we can open
up the preview that's here and see how that's looking on different types of objects so this is what
it looks like on a sphere.
This is what it looks like on a plane.
This is what it looks like on a cube Suzanne etc quite powerful options there.
Well see what it's going to look like on other shapes.
So let's try to factor into their Again narrow.
It doesn't help at all.
All it does is make our image rather dark.
So we need something to convert to that.
So it's compatible with this normal inputs and we use a bump no to do that so let's go ahead and find
bumped node.
Well it's under vector of course you could search for bump.
So I'm going to add the bump node in there and using the fact I'm not going to control the normal angle
much control the height.
And then the output here I'm going to plug into that normal.
That is starting to look much better.
Starting get that bumpy feeling again.
Of course it's not going to change the edges or the actual geometry at this point in time.
Is only controlling how flight looks so we can change this distance here and set it up one.
And in terms of strength how well no one's a bit too much.
I think I would rather have it with a distance and maybe point to but slightly stronger.
That's up that's okay.
I would like it to be a bit more subtle than that so that's try point three and point five.
Yeah they're starting to look much better.
Of course we can tweak these to our hearts content.
And you know be happy with one one moment and the next.
We can also change the texture itself so I can make it a bit more bumpy.
Ah.
That is start.
That's starting to look a bit more interesting.
I'm liking how Suzanne is looking at this point in time.
So that's more of a kind of a rendered finish if I bump this scale up.
What does the detail though.
Well let's let's lower that down.
I think I am going to boost it up to maybe 20 or so.
This detail if I lower it all down it's always good to go to extremes with these will with no detail.
It's kind of a smooth bumpy and it tends to get well noisier I suppose with more detail in a distortion.
All that starts adding swirls.
That's kind of cool.
Okay.
So this is what I mean by the experimentation.
In fact Blender's gone a bit laggy whilst it's rendering things out there we go with experimentation
you can.
Okay this is no good for our particular wall that we're working on but that's something to remember
for later I'm pretty sure.
So I'm happy with a slightly larger scale there.
And so I'm going to go for too much more detail the eight.
They'll let somebody find out.
Now we've got that as we can see here.
It's I can't see the texture underneath anymore so I'm going to have to bring the strength down so I
can see the underlying texture as well that is looking pretty good.
I feel I'm going to have to increase the distance here.
And again these are tweaks you can go backwards and forwards to your heart's content and do now at a
certain distance it seems to make no difference because based upon this strength here I'm going to lower
that back down to say poitou so now our wall has a texture on it that will change based upon the light
hitting it which is very important that means we haven't baked the lighting information into any texture.
It's being generated based upon where the lights really are in our scene.
Now a couple of other things I would like to do here of course is I am at a stage for it.
Why am I going to do that in this particular solution.
And I'm going to play with these a little more until I get to roughly the right point where I want to
be.
I mean you can play with this all day long.
I'm quite happy with that.
Now one of the questions that you might have is well why didn't we just plug this factor straight into
that displacement.
And I'm just going to remove the normals that we've created.
Now there's a couple of reasons why we haven't done that.
The first one is we want to control the diffuse shader how to diffuse shader is being handled not how
everything at the very end is being handled so there's a slight distinction and difference between the
two.
But this is also a valid solution for the right effect.
Again like most things in blender as long as you get the end desired result a lot of using blender is
kind of a mixture of knowledge and just trying things out and making sure you're logical with how you
plug things in.
So in this case we do want to specifically control the diffuse shader and how that interacts with light.
If we plug it in all the way into displacement it changes how the whole object or anything else that
this material is applied to interacts with light.
So I'd love to see what textures you came up with and apply to your wall.
How did they look when you move them across to the building that youre creating.
Remember to share in the discussions and I will see you guys in the next lecture.