BUILDING A CHARACTER WITH POLYSPHERES

1. POLYSPHERES

This image was created in the latest version of ZBrush and uses the all new Polymesh feature. As with most of the newer features in ZBrush Pixologic provide you with an extensive set of ZScripts to help you understand the basics. Polyspheres is no exception. The ZScript is the best way to learn! Run them.
So, what are they then!. Polyspheres help you to model a large or complex mesh by allowing you to add inter-conected spheres to a group, one by one, until you have the desired shape. Remember when you were taught to draw as a kid? They told you to think of every object in terms of primitive shapes. Well this is the same only in 3D. Some people will liken it to metaballs but believe me, this is different.

The spheres that you have placed can be moved, scaled, rotated by themselves or as a group. To make an arm, you makes a ball, add a ball doe each joint and pull the fingers into the shape of a hand, easy.
Take a look at the new-look transform panel. See figure 1. Notice that SYMMETRY is now in with the transform panel?
When you are happy that the Polysphere model is complete you can then use a process called skinning. This creates a single mesh object based on the shape of the combined Polyspheres. There are settings for resolution and smoothness to help get the desired result.

TOOL POLYSPHERE

figure 1.

2. THE KROOT

I wanted to do this tutorial to show people how to take a character from an image and turn it into a 3D ZBrush image. For reference I used an image of a KROOT. This creature is taken from the War Hammer 40,000 game by Games workshop.©

3. MODELING

The Head

Although I wanted to make this image to show the Polysphere feature I decided to model a head separately. I used a basic 3D Sphere to create the head and added features in EDIT mode.
(How to model a head in ZBrush)

The Polysphere Body

The body of our KROOT is in a very defiant stance gripping his SPLINTER RIFLE. With Polyspheres you can set the symmetry feature so the body is completely symmetrical. For this image I needed to add spheres in a non-symmetrical way.

I started with a ball for the hips, a ball for the belly and one for the chest. I changed to with a draw setting of 1.
This then allowed me to move any of the spheres without effecting the others. Any setting higher than one and the areas of affect is increased. As you move a sphere, the interconnecting gray areas lengthens or shortens accordingly.

To continue adding Spheres I switched back to .

I continued adding spheres for the shoulder and legs. I moved them into place and moved onto the left arm. Down the arm and onto the hands and then fingers. You need to be sure you are placing the joints in the correct place early on in the process. For example. If you wanted to move the entire arm later in the process you would have to reposition every sphere in the lower arm and hand. Get into the habit of positioning the parts right first time.
This is where a good reference image helps. One way to be sure is to load the image you are trying to re-create into a back layer of the document. That way, you can match the spheres to the image as you go.

After a short while I had a full body (minus feet and a head) and I was ready to turn the Polysphere object into a mesh object by skinning it.

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4. SKINNING

To turn the object into a ’skin’ or a mesh object you now need to press ‘MAKE 3D SKIN’

This will create a new mesh in the TOOL panel. You can change skinning settings to get different type of objects.
For this one I used a resolution of 256 (maximum) and a SMOOTH setting of 20.
My result can be seen below. This mesh or ZTOOL can now be altered as per a normal ZTOOL, i.e.. with the and features in the TRANSFORM panel

5. TEXTURING

I tend towards TEXTUREMASTER for this type of image but on this occasion I decided to place all the body ZTools (Objects) into the image and then paint and texture them in the canvas.
If you ever decide to use this method remember that you will have no texture saved with your ZTool and therefore will have to redo a texture every time you use that ZTool.
I used three BASIC materials for the skin and decided to aim for a yellow/green skin tone. The materials had differing levels or NOISE, NOISE RADIUS, COLOR BUMP and specularity. I like to use a NEGATIVE number in the COLOUR BUMP as this helps to ‘raise’ light colored veins and arteries.

6. THE BACKGROUND

The background for this image was created by adding a 3DPlane to a background layer and painting onto it with the SIMPLE BRUSH. For this image I used a BASIC ALPHA BRUSH and the DRAG RECTANGLE stoke type. This process lets me build up layers of colour that quickly start to look like clouds or smoke.

7. MULTIMARKER GUN

Although Polymesh allows you to make complex organic meshes I still like to use the tried and tested Multi-Marker. This little gem lets me take a set of primitive shapes and add them all together into a Polymesh object.
One tip: Make sure that when you modify objects they you do it using the deformations panel. If you just change the sizes on screen the mesh doesn’t work correctly.

::GFXZoOM |source:highend3d.com::

Link: www.luxology.com/training/video.aspx?id=6

Sculpting Details
Now I am prepared to send it into ZB.  The exported model will be sent as an OBJ with US, this will insure a similar result when I bring it back for render.  I will then start detailing all the layers, like body, clothes, etc. and this is the fun part project to work on!  The look that I was going for was big and muscular with lots of fat.  Using ZB’s new tools made it easier for me to get it closer to my original ideas and this possess will take about 5 to 8 hours.  Once I am finished, I go back to it’s base level and generate a normal map, about 4096*4096 tiff.   I would also create a cavity image for diffusion using the Zmapper on ZB.  Now I am set up for using this developed info in the Texturing stage.


Texturing
I now get into coloring the subject, and to get it to look the way I would imagine, I have created a color image with bumps, Tattoo images, defused maps, specular, etc.   It is a long process and depends upon layering and compiling these details onto each other.  I usually just start with the skin color and take it from there.

Rigging
Once I am finished with the look and the colors, I send it to LW 9.3 and  I start developing the bones for the posing and all the necessary weightmaps to pull the geometry with the selected bones.  Again, this is a slow process with a lot of testing to make sure I get the right functionalities.  Once the naming is finished and the bones function properly, I start rigging it in a simplistic manner, I need the legs to bend properly and the arms to fold in with the shoulders.  Once that is done, Posing would be the next step.

Posing
I usually have a pose or a position that I have in mind before I even start.   It is just a matter of tweaking until I get it just right and when it is set, I would then freeze the pose and send it back to Modo.  I would then sculpt any small problems to make it look even better in the pose.

Stage Set
This is when I get involved with the positioning of the camera and the angles.  From there I decide on what I want to see from the lens and start creating the ground with all the texture and reflection maps and I also start putting in the boy and the rocks.  Here I rely not only on my painting skills but soak into my photography background to create the set which is very important to establish the mood of the story.

Lighting

In this scene I rely on two lights & GI: one of the lights behind the character and the other is at an angle to the front.  GI is using a global color that I carefully choose to get the best result and effect.


Rendering
I would now put together all the final details onto the camera like DOF and anti-aliasing. Also, I would render one go with all the objects, then I would render every element on its own, so that I can get better control while compositing on PSD

Compositing
Then get into the PSD and align the layers on each other.  I would start illustrating the smoke by creating many layers of transparent smoke effects using my Cintiq monitor to paint in these details.  Also the birds and the sky would be put in position with a view to adjusting the look of these elements.  By this time, the image will be getting near to its final look, and I might again adjust the overall colors. 

With the tools we have today, the work flow is much better and I would always encourage the artist not to be restricted with one application, but go into all the tools that will help him create a better art piece.  I would say that we are lucky to have all these tools and life has never been easier for the CG artist . Finally, I would like to say thanks to CGArena for giving this chance and others to show around the world how different artists think when they create their art work.

By Khalid Abdulla Al-Muharraqi

.:GFXZoOM|source: cgarena.com::.

Modeling in Maya
Create a simple straight line and a circle so it will look something like this

Pick the circle then the line, hit surface – Extrude
You will have a basic cylinder.
The point that I would like to illustrate is the fact you can manipulate the cylinder after it has been created because of the action history.
You’ve got to love that
Now change the rotation to 360, so we have this nice spiral isoparm — this is what we are looking for.

Right click on the surface — choose Isoparm, and pick any of these spiraled Isoparms.
Choose Edit curve – duplicate surface curves.

Now you can get rid of the cylinder, it served it purpose.
You should have a nice spiraled curve.
Move and scale the circle that we used to create the cylinder and place it so it’s centre is on the first CV of the spiral curve.
TIP: to place it precisely, pick the circle, right click on the curve, and choose control vertices.
Now move the circle while hitting the “V” button or snap to curve

Rotate and adjust so it will look somewhat like this
Pick the circle and the curve and hit delete history to get rid of all the past nodes

Choose Surface, Extrude
In the input channel of the new surface, change the scale to 0.05
Note: You can change the scale to be 0 to have a closed surface but I prefer to do this step towards the end. However, it is up to you.

We need to get this surface ready for Zbrush, so hit Convert – nurbs to poly and open the options window.
Choose Quads (Zbrush only takes quads) and Tessellation methods – control points
Note: You could have done the extrude directly as polygon.

Delete the original surface and rename your new poly to “horn”

Export it as an OBJ file
Note: Zbrush only takes Quads, so keep that in mind every time you export to Zbrush

Open Zbrush and under tools – import, bring your OBJ file horn_ZB.zip

Now you should see the horn in your tools as an icon. Pick and place it in the drawing canvas.

Now before you do anything else, immediately after you placed that OBJ in the canvas,
right click on it and choose edit. Other wise you will be “drawing” more horns.
For more accuracy, hold down the SHIFT button while placing the object on the canvas, so it will rotate on a 90 degree angle.

Now for some housecleaning. I placed my tools and transform menus on the left side of my canvas by clicking on the small circle on the top left of the pull down menu.

Under tools – Geometry, hit divide 5 times
Every time you divide, the poly count will quadruple. In order to see your poly count, move the curser over the OBJ thumbnail in the tool palette.

Now for some sculpting.
First we are going to target the areas that we would like to sculpt. To do so, we are going to mask some areas of the object. You can do this by holding the CTRL button while painting.
You can adjust the brush size by right clicking on the canvas, and it will show you the options for the brush. You can also get the brush options from the top menu.

After a couple of strokes, you should get something like this.
Note: holding the CTRL key while painting will mask; while holding CTRL & ALT will unmask

Then under tools – deformation
Choose inflation and make it 100.
Now we have the base shape.

Unmask all, and let’s get to the fun stuff: “SCULPTING!”
Hold the shift button while you brush on the horn. This will SMOOTH it out for you. Again, adjust the brush size and intensity to your liking, until you get something similar to this.

Use the brush for painting over the horn. To add more deformation to it, experiment with the Zadd, Zsubb, Move, and Smooth brushes
Mine looked something like this.

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Time for some detaling.
Choose the projection master, and make sure it is for deformation only on one side.
Drop your object.
Now let’s add some scratches to our horn. Once you are done with this side, click on the Projection Master again and pick up your horn.

After a few minutes of painting and sculpting, and using the above tools, you will get something like this. It is now time to export your work.
Again, if you want to know how many polys your object has, just move your cursor on top of the tool menu, and it will give you that information.

The next step is to prepare the model for Maya. When that model goes to Maya, it will be converted to Sub-D or poly smoothed.
So what we need now is the cage model. To do so, we go to Tools – geometry, lower the division to 2, and hit the cage button.
You can delete that first level now by hitting Del lower

Let’s make our UV map. Under tools – textures – AUV tiles, it will make a UV map that has a perfect square for each poly face.
Note: you could have done that step in Maya. Prepare the UV map the way you like it and then when you export your OBJ file it will have the UV done already.

Export the cage OBJ by using Tools – Export. It will save it as OBJ file which has a UV map on it. We will need this in Maya.

Time for displacement and bump maps.
Displacement:
At this level, which is now level 1, of the OBJ cage, go to Tools – Displacement and choose subpix between 2-4. The higher it is, the more accurate your map would be, and the longer it will take to generate. I usually choose 4.
The map size by default, is 1024. I made it 2048 for a more accurate result.
Notice the bar at the top of your screen. It will tell you how long it takes to generate that map.

It will be placed in the alpha tool palate. Highlight it and go to the alpha pull down menu.

Look at the alpha depth factor, mine was 0.9825. We will need that number later in Maya. While we are at it, hit the flip Vertical button.
(That step could be done either in Zbrush, Photoshop or Maya…it’s up to you.)
Hit export, choose tiff format and store it on your HD.

Time for the Bump map.
This is the same thing that we did before, only this time we are doing it at level 3, (it was level 4 before we deleted the lower one.)

Working with Photoshop
Before we start with make sure your Photoshop setting is on ‘No color management’ under
edit > Color setting
set it to Color Management off
Open photoshop and choose Image mode – RGB
The reason we did this, is because maya cannot read Grayscale.
Save your new file and lets call it ‘texture 1′

Image adjustment – Auto contrast
Note: The image we got from Zbrush is gray color. Maya needs a range of black and white to make a proper displacement. I’m not going to get into the details of that , but in a nut shell Maya need a value of Black and White to make a proper Displacement and Zbrush gives a value of gray scale.
Some 3D packages can do it internally. However I could not do it in Maya, so I did it in Photoshop.

Save your new file, and lets call it ‘texture2′
For the bump, convert it to RGB. You do not need to do the auto contrast.
Here is how the Displacment maps I’m going to use look like.

::GFXZoOM |source:highend3d.com::

A while back I created a new model using ZBrush as part of an advertisement for Pixologic at Cinefex Magazine. My idea was to create a digital Picasso, having some fun while he was painting with ZBrush. As Picasso’s likeness for a commercial piece is not allowed (because of the copyrights) I changed the final model but kept the main idea. Picasso’s Portrait is now part of a personal project. I’ll try to explain my creation process for this model in this tutorial. I don’t think my techniques are something new, but can be useful and insightful for you.
I hope you enjoy.
Click over the link to download all the shaders and light setup :skin_light.zip

Modeling:

You will find that I started this model as a caricature but then decided to change and make it realistic. In some parts of the video you will see some drastic changes in the head shape that I did after finding some better references of Picasso
For the modeling process I used some of the most common ways to sculpt using ZBrush. I started this model with few ZSpheres, converted it to mesh and started to move points to get the initial form. After this I created some more loops to help with the definition and flow of the form, then I started to subdivide the mesh to add more and more details. If I needed to correct something I just went back to the lower levels and used the smooth brush to “erase” any problems then I went to the next level up and kept working in the same way until I achieved the desired result. Doing things this way will allow you fix problems in your mesh much faster and with greater precision than trying to correct it at the highest levels. To avoid issues like that is always best to add details slowly, trying to get the most you can from each level of subdivision.
For the wrinkles I used the most common technique: Projection Master with DecoBrush. In this quick example you can see some random lines I created using DecoBrush:

Back to the 3D Edit mode I use Transform > Inflate to fill the areas between these lines with some volume, using a small-medium brush size. To make the edges softer I use Transform > Smooth. I keep using both Inflat and Smooth until I get a result I am satisfied with. Remember that the quality of the details depends of the number of polygons of your mesh since we are working with sculpture, not bump maps:

Textures:

For the texture painting I used SimpleBrush combined with different alphas and Colorized Spray as stroke type. I started with a neutral and very light skin tone and I added different tones with a very light pressure (about 3-4 on RBG Intensity). I slowly added different spots and colors like I was painting in transparent layers of color.

Here you can check the texture without the correct shader and light yet:

Skin Shaders:

For the skin shader I used Sokar’s solution and changed some parameters to try to improve even more on this already amazing shader. This shader is based on ColorizerTrishader and works pretty well in the skin simulation tones, faking some sort of subsurface scattering appearance. If is your intention to mimic this material for your own study using the screen shot below, please pay attention into the diffuse curves . To make this shader to work properly you need to set up very high values to the diffuse curves on channels S2, S3 and S4. This will cause your model to appear very “self illuminated” in the view port but don’t worry because after you hit the render button everything will be fine

After you conclude the creation of the main skin shader using the parameters above (or importing the skin shaders you just downloaded from this page) you need to copy this shader to another channels. To do so, just click over the material you just created and click on “CopyMat” button. Now click on the next material slot and click on “PasteMat”. Repeat this step for the next 4 slots.

Now that you have 5 identical materials you can start to adjust one by one, adding a little bit more of specular in the second one, even more in the third one, fourth one, fifth one. Now you have a library with 5 similar materials different just in the amount of specularity.

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Multiple Shaders (for specular variation):

Now you can start to paint different levels of specularity to make your model more appealing. As you know our facial skin has different levels of specularity. Areas such as nose and forehead are naturally more specular. Areas such lips, eyelids and internal part of the nostrils are naturally humid in different proportions. Have this in mind in order to create your shaders with the right amount of specularity for each of these different areas.
Before starting, click on the first shader slot (or the one with the material with less specularity). Load your model in the viewport, click on Edit. Change the color to white in the picker and go to the texture menu. Change the values for Width and Height to 3000 to have some good resolution. Click on “New”.
Click on “Projection Master” (G on your keyboard) . Choose “Colors” and “Shaded” (is up to you to use “Double Sided” and “Fade” options). Click on “Drop Now” button. Click over the second material slot (some material with more specularity than the basic one). Choose “SimpleBrush” under the Tool menu. Choose the alpha you like more to simulate different levels of specularity for pores. Change the stroke type to “Colorized Spray” and change the flow value for something very low like 0.01. Change the placement value to the maximum (= 1). Change the brush size to something very small. Try 3 or 4. Now you can start to paint more specularity in some areas as described above. You will see the result in real time and using these settings we will surely avoid the “plastic look” because you are simulating different specular levels and also the pores on the skin. Finishing with the first specular level, click on “Projection Master” again and choose “Pickup Now”. Rotate and positioning your model and repeat the last step and before to start to paint, just choose another material.

Eyes:

For the eye material I used the same skin shader just tweaked to look similar to the ToyPlastic shader (very specular). For the texture painting I used Projection Master mode for the main texture painting. Back to the 3D mode I used the radial mirror on Y axis to paint more details and also add some effects with another brushes like BlurBrush and Smudge.

Here you can see the final texture and the final shader, based on the skin shader but much more specular to mimic the ToyPlastic specular level.

Lighting:

My settings for the light are very simple and based on Sokar’s light. I used just one light with the settings in the next image. This light gives a soft look to the image with some nice soft shadows.

::GFXZoOM |source:highend3d.com::

Render:

Here is the result using this simple solution for lighting without any kind of adjustments or fine tuning…

… and here you can see some different results after some adjustments using the built-in tools under the Render menu for color, brightness and contrast in ZBrush:

Don’t worry about the self illuminated look of your model in the viewport. This is caused by the parameters in the skin shader…

… because after you hit the render buttom everything looks nice again

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Final Touches:

Because ZBrush is an amazing hybrid solution where I can work with 2.5D and 3D all in the same environment, I find the best way to paint hair is using the DecoBrush. With this brush you can achieve some nice effects because of the fluid way that you can paint with it. To get the best results, the use of a good tablet with pen pressure becomes essential. Before to start the hair painting I baked the layers (ctrl+b) and started the long hair painting for the head, beard, eyelashes and eyebrows. To do so I used DecoBrush, Brush 35, DragRect Stroke, draw size = 0, focal shift = 0. You may find it a little difficult to paint precisely using this brush at the beginning but you will quickly understand how it works and will get your best results after some training.

For the final image I used the same model but I had to change Picasso’s likeness to avoid problems with the Copyright since this work was created as an advertisement for Pixologic (Cinefex Magazine #100). Every new model was created using the same skin shader as base, even for clothes, background etc. Using this shader and light as base you can get a pretty decent soft look to any of your creations. Just give it a try and I’m sure that you will enjoy the results.

I hope this tutorial proves to be useful for you guys and thanks to Pixologic for this amazing piece of software!

Krishnamurti “Antropus” Costa
CG Artist
http://www.antropus.com.

::GFXZoOM |source:highend3d.com::

Start Tutorials

1.

Get yourself a model that needs some hair.

Render him out using BEST RENDER in the RENDER panel with whatever light/material/shadow settings you need for your scene. Once the scene is rendered go to the LAYERS panel and hit the BAKE button.

Now go over to the TOOL panel and locate the FIBER BRUSH from the popup menu

Now to see how NOT TO DO IT just draw a stroke across the head without adjusting any settings. The result is a solid mass of dense hair that looks out of place.

To change the look of the FIBER brush hair there are a number things we can do. First is to change the Material to FLAT.

Then lower the RGB INTENSITY and the Z INTENSITY a little: experiment to achieve the desired effect. Vary the DRAW size to lengthen the strands as needed. Small DRAW size = short hair. All sorts of effects can be achieved with just these three before we even start to edit the FIBER BRUSH settings. If you are using a graphic tablet you will see that the FIBER brush is pressure sensitive, more pressure, more hair.

Next, go to the TOOL PANEL and take a look at the settings in the FIBRE BRUSH panel. Most of these are self explanatory and if you hold down CTRL whilst hovering over the item ZBrush will tell you what it does anyway:

Armed with the above info you can set about spraying hair onto just about anyone or anything in ZBrush.

::GFXZoOM |source:highend3d.com::