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  Anatomy of a Wall - PART 1
   

 



STEP 1 - WHAT
The image above uses the built in Stone Wall from Bryce. In order to create a better texture, I must be able to identify what I don't like about the Bryce material. Let's see... what don't I like about that material?

The joints between the stones are raised not sunken... i.e. they are white and the stones are black.


1. The pattern of the stones are too repetitive.


2. Of course, not much color.


3. I applied the texture to a cube and the edges of the cube are too prominent.


Well! Let's fix the mortar between the stones!




STEP 2 - FIXING THE MORTAR 1
1. Open the material and enter the Deep Texture Editor.







Then:








STEP 3 - FIXING THE MORTAR 2
What do we do when we are in doubt about a texture? Right! Turn off Color. So, Click on the "C" in Component 1 and turn of the color in Combination like shown below.







Render. - Good gravy!! What's this? Could it be where there is white in bump that it appears to lower the surface? Yep! Sure is! Well, well. well.








STEP 4 - FIXING THE MORTAR 3
What we want is to view our material while creating it just as it is going to be on our object. We have just discovered the use for negative bump. Change the bump setting as shown below.







Render again. Gadzooks!! We are getting somewhere!








STEP 5 - WAR AGAINST REPETITION
Load the base texture (BaseWall.mat) from the download. I have done several things here and I am going to go through them. I provided the base texture to spare you from the work. But, you if you plan to work in the DTE to create your own materials, you should try to understand and duplicate my work.







Component1

I turned off Alpha because it will interfere with the next to channels we use.


Set the first two colors to black. I want the divisions between the rocks to be clearly visible. Set the third color (top of the rock) to light brown.


The mode under the dropdown (not shown) is set to Linear interpolation 3.


I reset the frequency of X,Y, and Z to give me a little better relative size of the stones.


Filter - Adjust "A" and "B" for clear divisions between the rocks. Change the mode to Clip aX+b ( from Smooth Clip Ax+b) for sharper transitions from stone to crack.


Phase - The secret ingredient! It is so in many of my materials. :)







What we want to do here is move the edges of the rocks in a random way so that they are not so repetitious. The edges will be affected by the Amount of phase and frequency. Grab the Frequency adjust and vary the frequency while watching the stone positions in the preview. Rotate XY and YZ and observe. Change the Amount of Phase, carefully in small amounts and observe.



STEP 6 - CHARACTER AND COLOR
From here on out, it becomes subjective. What I mean is that you may see stone walls differently that I. If you live in an arid climate, there may be no moss. But I'll show you the hows and whys of the stone wall I created.


Add the B channel with Procedural Blend. Use Spline Interpolation or Linear Interpolation 3. (Click on the little dart at the bottom left of Component 2). The purpose of this channel is to add detail on the surface of the rocks.

Choose a noise, that suits your fancy [I like Weird Value :)] and set the frequency high.








Add the Filter with Clip aX+b and adjust "A" and "B" so as to not blow out the detail of the individual stone cracks. You may have to test render of see REALLY how you are doing at this point. Let the render run through antialias to bring out the detail by smoothing some of the noise. Plop render works well here Then throw in some Phase of another noise.







Chose a cloud like noise for the 3rd channel. Set the filter to Gaussian(a(X+b)) and adjust "A" and "B" in the Filter for the amount of moss you want on your wall.





STEP 7 - ANTI KNIFE EDGES
Surface and Edge Character

1. I have tweaked the phase amount and frequency in component 1's texture of the wall mat to give a little sharper definition to the rock for this example. Also, I mapped the material to a cube. Download this material if you want to follow me.


2. Create a cube and apply the texture downloaded above. Create a second cube and size like the cube on the right.


3. Place a radial light behind the camera, move it way back. Set the light to not cast shadows, no fall off, and intensity to 1.


2. Move the sun until the second cube that looks like a post casts a shadow on to the rock wall.


What is wrong with the shadow on the rock wall? Yep! It is a knife edge shadow. You could use soft shadows but even that won't give us what we want. Normally the surface of the wall would vary because of the rocks. The shadow would be distorted by the differences in the surface.

Ok, let's attack this problem.

Select the cube and use the Edit menu to convert it to a Lattice. Click and hold the double arrow and select Lattice as shown below.







Oops!










STEP 8 - ANTI KNIFE EDGES 2
First, select Object Space from the Edit menu under any of the transformation tools icons like below.







Click on the "A" to expose the attributes menu. Set the rotations as shown.










STEP 9 - ANTI KNIFE EDGES 3
Rescale the lattice until it is approximately what the cube was. We could have rotated the cube from the beginning to keep from doing this. Well, sometimes I don't think that far ahead. :)


Click on the "E" for the Lattice to open the Terrain Editor.


Set the resolution of the terrain to 1024 or higher.


Select the noise type of Cauliflower Hills.


Click on Fractal until you get a fairly detailed terrain.


Adjust the height of the lattice to your preference. I use Raise/Lower and Equalize to take out the drastic elevations so that it looks something like below. Alternate between these two controls to make the elevation terrain pretty bright. If you don't your wall will be very thin. Also, Select the Dropdown, shown below, and choose Solid.







Select Done and exit the Terrain Editor.


Adjust the thickness of your wall until you are satisfied. You should have something like below.








STEP 10 - HERE
Before we start into the nuts and bolts of a more intricate wall, it is necessary that we understand a few of the Deep Texture Editor's basic functions. These are Frequency, Phase, and the Filter. Additionally we'll cover mapping mode. color and scaling. Previously I have been focusing on results rather than detail. It has been brought to my attention that people can duplicate my settings and achieve the same results but cannot deviate from them without losing themselves in the mire of the DTE.

So, in this part of the tutorial I am going to backtrack to some basics. It is obvious, however, that most will not want a bunch of technical babble in the explanation. If you want that kind of information, I am going to disappoint you. Agreed... it has helped me understand how to use the DTE but it is not necessary.








STEP 11 - PHASE 1
It is VERY important that in any beginning that you know where your are when you start. If you don't, you won't know where you are going. :) So, load my ultra-secret nothing Sine material (NothingSine.mat). As you can see from the image above, very nice wood wall boards can be made with just Sine! This material has all of the settings you will need to start creating ANY material.







Import the "Nothing Sine" material into your materials library. Create a cube and apply the "Nothing Sine" material to it.

Go into the Deep Texture Editor by clicking on the red square shown above.







Notice the settings outlined in yellow. No Filter, No Phase, and Component 1 with just Alpha and Bump. Mode=Standard, Octaves and Direction in the noise palette are set to 0. If there is a secret or key to learning the DTE, this is it. That is simply to start creating any material from a known point. That way you will be able to see the effect of any adjustment. Render it as it is and all you will see is disappointing dimples on your cube.


But! Are you getting excited now that you know where to start? Ha! I still do! I know that there are many surprises ahead! As I experiment, I look at a test render of each step and I go through the "Hey, that looks like a ....". If it is good enough, I save the material to come back to it if it doesn't fit what I am trying to achieve.





STEP 12 - PHASE - THE FILTER (AN ASIDE)
The filter is one of the key ingredients in any DTE material. AND its function is very easy to understand. The filter is simply a Contrast and Brightness control just like you have on your TV. Brightness brightens everything. Contrast makes grays blacker and whites whiter. In the case of Alpha and Bump, it simply raises, lowers and changes the contrast between the raised and lowered parts of the surface.

Take Clip aX+b for instance. the aX portion of the formula is Contrast. The b portion is brightness. So, when you adjust the "a" value in the filter, you are adjusting Contrast. When you adjust the "b' value, you are adjusting the overall brightness. For the techie, aX changes the slope of the line from black to white and b offsets the whole line from zero.

Because the RGB color palette in our computers is limited to a brightness value of 255 for each color, we have only two choices if we try getting brighter than 255. We can either clip ( stop at 255 ) or fold it. To fold a value above 255, we simply start subtracting the difference from the maXimum value of 255. I.E. If we clip 300 at 255, we get 255. If we fold it, we get 255-300 = -45. 255 - 45 = 210.

So, all of the different modes in the Filter either clip or fold to modify the brightness and contrast of the noise. We cannot get brighter than the brightest or blacker than black.

So, lets see what's what:
In the Filter, Select Clip aX+b.






Now, adjust "b" (brightness) up to about .5







There are several things worth noting here.

The black area got whiter - notice it is now gray.

The white area got whiter and larger! What happened? Well the very white part could not get whiter but some of the formerly gray area got moved to white and was clipped. So, the circle of white got larger.

Notice the graph in the Filter palette. The slope of the sine wave in the graph area did NOT change. But the entire sine wave was moved up and clipped at the top.



STEP 13 - PHASE - THE FILTER (AN ASIDE) 2
Click Reset.







Now adjust "a" to 30. Notice the graph in the Filter palette. Now the slope has changed and the black to white Rate of change has increased and was clipped at the top..

Adjust "a" to read exactly 30







Tip!

Adjust "a" by dragging the mouse left or right to get as close to 30 as you can.

Without moving the mouse let off the left button and then click and hold again. Adjust as close to 30 as you can.

Without moving again, let off the left button and then click and hold again. Adjust to 30.




STEP 14 - PHASE - NOISE (AN ASIDE)
Now adjust the "Y" frequency to 0. Uh Oh!!! I guess you can see where we are going now! But before we go much farther, I had better take some time to go over a few things in the Noise pallete.

Change Octaves to 1 as shown below. Adding Octaves is equivalent to striking two or more keys on a piano to play a chord. It looks like Bryce adds an even multiple of the original frequency to the mix. This creates a more complex wave form with harmonic content. The higher the Octaves, the more notes are played and the richer the content.

In this case, the multiple canceled out the number of lines and blurred the ones that were left.







Increase the frequency of X and Z by 2 times and adjust "b" in the Filter down until you get what is below.










STEP 15 - PHASE - NOISE (AN ASIDE) 2
Increase the frequency of X and Z by 2 times and adjust "b" in the Filter down until you get what is below.







It looks like we are right back where we started. In fact, we are not. We just can't see the harmonic content because of the Y value. Change "Y" frequency to 200.0.







Mushrooms! You now have seen a chord! The more octaves, the more complex the interaction.

Now flip the Octaves to 0. Back to dimples.

Put the "Y" frequency back to 0 and "X" and "Z" frequency back to 100. Reset "b" in the Filter to 0.

You may wonder why we are setting "Z" when it appears to have no effect. Well it does. If you check the sides of your cube with any of bumps we have created, it will have the same pattern. So, for this exercise, keep "Z" the same as you have "X" if you want a uniform pattern for your object.

Well, the use of Octaves is just great for mixing even multiples of frequencies of our original noise with itself. But how would we mix uneven multiples or even different noises with our Sine to create complex or even chaotic noise?




STEP 16 - PHASE - DEMYSTIFIED 1
Your phase adjustment is nothing more than a way to mix noise. Phase, in the technical term, is the relationship between two different waves in time. In our example, we are going to mix two sine waves. In some places on our object, they will add to each other, in others they will subtract. Because, we have the "Y" frequency at 0, their places of adding and subtracting will be only in X and Z on our object. In some places they will add to make a high bump, in some places they will subtract to make a low bump. In some places, they will cancel each other or be somewhere in between.







Before we start, your Noise should be just like the Noise palette shown above.

Click on the green button in Phase.







Set your phase settings as shown above.



STEP 17 - PHASE - DEMYSTIFIED 2
Setup the Filter as shown.

Now adjust the Amount of Phase as shown in the image above. I stopped at 228. Watch the lines in Component 1's preview window. Change "Y" in the frequency of Phase and play with the Amount of phase. Look for a repeat or a pattern of lines that suits you. Select done and test render to see if the bump suits your fancy. Also, tweak the filter for the depth of your gaps between the boards.

The Next Component







Chose Blend Max and Set the filter to Clip aX+b. Choose Fract Stone for the Noise type and set it up as shown above. The low number in the "Y" frequency stretches the pattern for the grain in the boards. Octaves at 2 smoothes the edges and adds richness to the texture. Use Linear Interpolation 3 or Spline Interpolation for Component 2. ( Click the dart at the lower left of Component 2 ).

Now click the Green button to the left of Phase.







Play with the amount of phase, currently 185, frequency, and Direction to create your own grain. Adjust the frequency of the Noise too. Change the noise source, i.e. try square or Rnd Linear or whatever you fancy. You should be able to play now. :)






STEP 18 - COLOR AND COLOR FILTERS 1
I carefully avoided color in the previous sections of this tutorial. Color adds a whole new dimension to the materials we create in the DTE. What we have done up until this point is exactly what I did when I was ( still am ) learning the DTE. I took one area and learned what I could. By confining my attention to Alpha, Bump, the noise editor, and the Filter I was able to understand a little. Trying to do it all at once was overwhelming!

You may also wonder why I have confined my attention to repetitive pattern materials. In order to see the effects of parameter adjustment, repetitive patterns show the result more easily than complex materials. The same is true for color.

Color - Setup

Load my handy dandy neutral sky in the Sky Editor.

Create the proverbial cube.

Load the Nothing Sine Material.







Change the Noise Type to Square.

Change the Noise to 3D.

Make sure that Filter is None and Phase is 0.







Click the little dart at the lower left of Component1 and set the color mode to "Spline Interpolation"



STEP 19 - COLOR AND COLOR FILTERS 2
Set the color to easily recognizable colors like shown in the image above.







Click on the "C" in Component1's palette. Where is our red? Let's see if we can force it.







Choose Clip aX+b in the Filter and Click Reset.




STEP 20 - COLOR AND COLOR FILTERS 3
Set our "Brightness" control "b" to about .5. Notice that our blue has been replaced with red. Our bright white-red has stayed the same.







Ok... Let's change our brightness to -.5. Notice that the squares are now using the top two colors . If you watched as you changed "b" slowly, the middle color mixed the the color you were replacing in varying amounts.

Change "b" to be almost 1.0 and -1.0 and observe the color in the preview window. Notice the relationship between the position of the wave in Filter's preview. At 1.0 you are entirely clipped at the top. At 0.0 you are entirely clipped at 0.0 at the bottom.

Ok, now the big question. Why can't we adjust the Filter to display all 3 colors at the same time? Ok... time is up. The problem lies in the nature of the noise we are using. Click on the "C" to turn off color. Note that the squares have no gray. Remember what I said about turning of color when in doubt? They go from black to white very quickly. Therefore we can only display two of the three colors at the same time in component 1 because we have only black and white in the noise. Move "b" with the color off and notice when you get gray. Turn the "C" back on. You will now show the Middle color but will lose either blue or the white with a touch of red. ( I didn't use pure white with that color )

Also notice what color corresponds to the Filter's output. It is counter intuitive but the order of the color buttons in Component1 is reversed. The bottom color represents the top (white) of the Filter's output. The position of the other two colors are shown below.








STEP 21 - COLOR AND COLOR FILTERS 4
So, how would we get gray into our squares and still preserve the square? See above. :) Remember what I said about Octaves is like striking two or more piano keys? Are we making harmony or what? :)

Notice the different shades of color. This is accomplished by the mixing of the square noise with a multiple of itself. At some points the two noises add to each other and at some points they subtract. The net result is a gradient from black to white in alpha and bump controlled by the Filter.







Now adjust the filter like the example above. Try negative numbers in "a" and positive numbers in "b". Reverse that logic and try positive in "a" and negative in "b".




STEP 22 - QUANTITIZE AND MORE - FILTER MAGIC
If you want a complete material for the material above - Bryce 5 - Download it from -

http://www.janthevillageweaver.com/special/anatomy_of_a_Wall/downloads/Color_Tutorial.zip

You
will have to rotate the cube to see this pattern. If you want to know why the sides of the cube have different patterns, read on. :)







Go to the Filter and choose Quantize. Click on Reset.

Although Quantize isn't really suited for this kind of noise it easily demonstrates its function. Additionally it demonstrates our brightness, contrast, and color mixing model of the Filter. Looking at the graph in the Filter preview, our model doesn't seem to work! Notice that we appear to be in the middle to the top with our wave form. Why are our blue squares being shown?







The fact is that there is a middle to bottom part of the wave but it is so small we can't see it. By making "b" a very very small negative number, we can see it. Adjust "b" until it is slightly positive. Our model holds true! Notice that the middle color and the top colors are displayed without the blue. See Next Step



STEP 23 - QUANTITIZE AND MORE - FILTER MAGIC 2
What is Quantize?

What Quantize does is Step the contrast, brightness and color mixing from black to white, from color to color. Let's check it out.







Adjust "a" and "b" as shown above. The middle step allows our red to be displayed. Notice c = 2. Change that to 4 and Adjust b to the value shown below. Vary "a", "b", and "c" and observe. Various patterns and different shades of color can be had using this filter. Try using another noise that has varying shades of color using this filter. Quantize will allow you to create stepped color changes with the number of steps determined by "c" in your materials.








STEP 24 - SIZE AND SCALING
Back out to the Bryce open screen. Size your cube and rotate to 45 degrees in "Y" as shown above.







Go into the Material Editor for the cube. Set the scale as shown above.







Set X,Y,Z to 40%. Make sure the mapping mode is Object Space as shown in the image above.


Render your cube. You should see something like this (below). Scaling is a balance between the frequencies of the noises and scale. Scaling affects all frequencies in the palette where the individual frequencies of the components in the DTE affect only the noise that it is associated with. Too low scaling will result in high frequencies that make it difficult to see what your work in the DTE.




STEP 25 - SIZE AND SCALING 2
Notice, in the image above, there is a balance of the texture with the cube. This is not always true particularly with asymmetrical patterns. A chaotic material, such as a rock surface, doesn't require precise positioning. But patterns can be a problem. Fortunately we have controls to fix that.

Go into the Deep Texture Editor for the material on the cube add some Phase as shown outlined by yellow in the image above.

Render.







I want to shift the pattern slightly to the left to balance it horizontally. Just how would I go about that? Well first I have to determine what axis of the pattern, X or Z, to shift. Remember we rotated the cube and we are using the Object Space mapping mode.










STEP 26 - SIZE AND SCALING 3
Position your mouse pointer over one of the handles on the left or right of the cube and pause. Gadzooks! We want to move our pattern in Z!

If you don't have a good render, render now.







Go into the Material Editor and enter -.4 into the Offset Z parameter. Remember... this control is scaled in Bryce Units... a little goes a long way.







We have shifted the pattern a little to the left. Use the same procedure to move the pattern up and down in Y. Use plop render to re-render half of the pattern to see how you are doing. See above.



STEP 27 - SIZE AND SCALING 4
Now go back to the wireframe view and click on "A" for the attributes of the cube. Change the rotations of XYZ to be 0,0,0. Render. See the results above.

What's this? We have different patterns on each side of the cube! Well, that is not an issue if you will only see just one side in the cube in your scene. However, if you wanted a column in your image to have a uniform pattern, what we have above would not be acceptable.

The reason for this apparent disconnect is somewhat difficult to understand. We have a 3 dimensional Noise mixed with 3 dimensional Phase. If you can visualize that, you will see that we are just seeing different sides of the mathematical results.

So, how can we get around this issue? Yes!! Change the mapping mode! Excellent!







Go into the material editor and choose Object Cubic for the mapping mode. Exit to the wireframe.

Render







Grrrrrrr!!! What?!!! If you go back to Object Space mapping and rotate the cube, you will find that this is one of the sides of the cube. In Object Cubic, you are only mapping One side of the 3D noise to all sides of the cube.




STEP 28 - SIZE AND SCALING 5
Setup as shown above.

Play with the Phase rotations to find your original pattern or a new one that you like!







More Fun







Go to the Edit menu and select the double arrow on the right. While hold your select button on your mouse down, move over to the cylinder icon and release. Converts the cube to a cylinder.



STEP 29 - SIZE AND SCALING 6
Rescale the cylinder until it looks like a column.







Go into the Material Editor and change the mapping mode to Cylindrical and adjust scaling as shown above.







Play with the phase rotation to get a pattern you like. Tweak the scaling.




STEP 30 - SIZE AND SCALING 7
This finishes the section on size and scaling. Can you imagine the different patterns that you can give your DTE textured obects? :)

Next - Into the Mix



STEP 31 - INTO THE MIX
Well folks, we are just about at the end of this tutorial. Hopefully you will be able to see why you have endured cubes, squares, patterns, phase and all of the other stuff. By understanding pattern creation, you will have the ability to create realistic or surrealistic materials for your images. Why? Because you know, in a general way, what effects what for any noise source or combination of noises.

For me, learning is a process not an event. It takes time for me to understand. I avoid getting frustrated because I can't grasp new ideas and concepts immediately. I learned this lesson a long time ago when I bought my first real graphics computer the Commodore Amiga. I bought the ROM Kernel, Windows, Hardware, and Operating System manuals. When staked up, they made a great foot rest. I couldn't get past the first page in any of them. But as I worked with the computer, each time I opened one of those books, I understood a little more. For me, the same is true for the DTE.

Designing a Wall

Create a cube and stretch it out like the one in the image above. Rotate it in "Y" to 45 degrees. Make it as you want.







Apply the Nothing Sine Mat to it and make sure that you have the World Space mapping mode selected.







Go into the DTE. Change the noise type and settings as shown above. The reason the Octaves are set at 6 is that I want rich detail in the surface of my wall. As I went up in Octaves, I went up in frequency to achieve this.



STEP 32 - INTO THE MIX 2
In the beginning, I don't want to use color. So, I adjust the color buttons, from bottom to top, in a gray scale. Basically this corresponds to the Bump and Alpha. After adjusting your color, click "C" on and off to see that you are in sync with the Alpha and Bump.







Select Done and go out to the Material Editor. Set your scaling to 20 as shown above







Render to see what you have. If the general pattern of white, gray, and black are not what you are looking for, go back to the DTE and change Frequencies or Rotation in X,Y, and/or Z to get the layout that you want. Don't worry about bump or color yet. All we are trying to do here is establish the relative sizes of white ( the good part of our wall ), gray ( the partially eroded part of the wall ) and dark gray ( holes ). We'll refine these later.