week11

Lighting and Rendering p.2

LightCaps

You have a lot more control with this lighting system. But keep in mind that Lighting works with Material.

Low Falloff -> sharp Light/ almost tune light.

Bounce light wont cast shadows.

Diffuse channel- color



Specular channel - reflections

You can add a light, that would have lets say only Specular channel- only the  specularity will show off. Its nice to use as a Rimm light.

In the Shadows BPR settings you can control the softness/ harshness of the shadow by tweaking the Rays and Angle amounts.

You can assign a texture to the light.

Or use HDRIs for your  environment and lighting.
If the shadows get clipped-> that means the grid of the floor is not big enough. You can make it bigger by going to Draw-> Floor Size

When you have HDRI on and press the big LightCaps botton, it will generate the lights from the HDRI.

Standard Materials

(to assign a material->have M on, go Color-> Fill Object)

1- Sculpt

2-Texture

3- Create Lights-  

                                                                        these two work together

4- Assign materials-

5- Render Settings

                                 *Shadows

                                                  *Ambient Occlusion

The three main sliders:

Ambient

Diffuse

Spec

Phong and Blinn Materials- the two main cg materials. When the slider set to 0- it is Phong, set to 1-> it is a Blinn
Phong- good for shiny stuff- plastic/ metal/..

Blinn- nonshiny - skin/matte plastic.

Anisotropic Specularity -

Spec Graph- how tight the spec is. The more 90 degree the graph is, the more tight the spec is.  the closer it is to 45 degrees, the smoother the spec.

In the bottom the colors of the swatches:

Diffuse - color

Specular- color of the spec

Ambient - sometimes washes out material color

Cavity - controls cavity's colors

Every one of these has a slider up at the top, that controls intencity of each channel. (Diffuse, Specular, Colorize Ambient, Cavity Colorize,..)

Filtering System

In Render Manu->BPR Filters

Clicl on a dot by the filter-> Filter is on

Filter->Noise / Multiply/....etc

Noise - strength of the Filter

Opacity - how much will go through

Mask  1- put only on character -1 -put on the BG, 0 -on both

Shadow to 1- tu put only in shadow areas -1- no noise in shadows

Fresnel- when smth faces the camera- won't get noise, when the surface turning- get noise

Filter->Colorise

Mask to 1- will put it only on character, turn Fresnel on ...+Red Color-> shows a bit as a skin transparency

Filter-> Blur

Depth on-> looks at what Is closer to camera, what's farther. You can put in an are of depth of field ( Depth A- where the Focus starts, Depth B - where blur starts).

- instant depth of field

Colorize-> Black

Edge detect - Toon shading

Radius- how big is the Radius of an edge (smaller dots- bigger dots)

Sensativity- how much plane changes it detects. Smaller-> only to major edges, Bigger->detects all skin pores

You have the same for Cavity.

Cavity Radius- how much of the falloff you get. Sensitivity- how much of cavity it detects

http://docs.pixologic.com/reference-guide/render/bpr-filters/filters-list/

As an example:

http://www.zbrushcentral.com/zbc-user-gallery.php?uid=81545

ToonShading

Choose Basic Material, effect the Diffuse:  Material-> Diffuse
Sterngth-> put to 1 (makes 2 values- light and dark)

Steps next to Strength slider set to 3-> will have more values for shading, 3 value tones.

The forth  highlight is a specularity, where you also can have steps->set to 2*

For the toon shadows-> BPRShadows, set Angle to 1 and Ray ->to 1

Materials-> Mixer-> Outline and Depth sliders for the Outline

https://pablander.selz.com/item/56150f14cca91800209bb084

MatCaps

https://pixologic.com/zbrush/downloadcenter/library/

Download, unzip-> Materials-> Load Material

or

You can make any material you want from an image of the material

Choose a big Image, that would have a roundness to it and therefore a lot of value change.

1.Select the Plane 3D ( a tool)

2. Select the Material Flat Color

3. Tool (in the right bar)-> Texture Map-> Import
4. Move plane to the top left corner and snapshot plane to Doc ( Shift+S)

5. Load the Demo Head ( it will swap out the plane)

6.Select any MatCap Material (*Pearl Cavity)

7. Subdiv Levels to model IF NEEDED( you want to have smooth surface)



8. Select the MatCap Tool ( in Tools->MatCap Tool) Switch when asked

9. First Click- is an overall color ( click on the Image)

10. Then click on Img to add values and tones

11. Alt+ Click on the dots to delete the Markers (5-6 is about enough normally)

12. For speck- click on the spot, hold CTRL and drag out - to effect how tight the Spec you want

13. Then you can tweak the Settings in the material tab

14. MatCap Mixer in the very bottom of the Materials setting -only available at this stage of material creation

15. -the last step- Select some different Tool, Draw out the Head or some other tool and go to edit mode.

16. Save the Material. Material->Save as...

You can still adjust the material with all the sliders with letter A in the Material Settings

or you can make it in Photoshop

Create 512x512 doc

Draw out a sphere, that clips to every edge of the frame. A slightly oversized sphere. (If you wont do that, ZBrush will grab the BG color)

Paint the Material.... Outside- the back of the model, Inside- what's inside...

Swap the img of the Sphere in ZBrush ( Pick whatever MatCap-> go to Material settings and click on the sphere img in the bottom, load the img you saved from Photoshop or Internet)

If you want to combine matcaps-
Put two spheres on one img. Place it side by side, crop it so it is clipped on all sides. Import into ZBrush, one sphere will effect the cavity, another- the surface. You can switch which sphere does what within ZBrush.





week10

BPR Render Intro

BPR- best preview render
(not PVR- physically based  render ), ZBrush does not have it.

SHIFT+R

Render- is Lighting and Material.
Good render is the good lights with the right materials.

Light

 

-3 Key Light System-

Key Light

Fill light

Rimm Light ( Back)

The First light,that is on by default is pretty much your Key light.

*Don't cranck up your Light strength too high- it is not realistic.

*Distance- the lower it is, the more it clipps shadows. Better don't touch it.

*Ambient- if you put it up, it lightens the colors...Better don't touch it either.

For realistic renders, better don't put in crazy saturation colors. Keep it subtle.

To make the light into a Rimm Light, get a mouse and click on the Dot on the Sphere in the Lighting render.

*Mess with lights separately, turn off other lights while setting up one.

Some people just use 2 Lights when rendering in ZBrush

BPR Shadows

FStrength - For the Floor to get shadows- lighter - darker

GStrength - the shadows on the model, for it to get lighter/ darker

Establish Shadow Resolution. To find a good one Start with double the amount you Document width resolution(the widest size). ( in Document-> Width..)

Rays - how many light beams it sends
Angle- the angle that the rays are spreading in

When angle is set to 0 - it shoots all Rays as one. As soon as you spread up the angle, it creates a cone to cast out Rays. Start with 10 , Render to see the difference.

*If you don't see the Difference, tweak the Model a bit. If you don't do it, Zbrush will give you the old Shadow that it has stored.

Sharp shadow = High Rays^  + low Angle
Wide shadows=  Low /mid Rays + High Angle

Soft Shadow= pretty low/mid Rays + High Rays

L Depth- Light Depth- moves the light closer/ farther from the object

Don't really touch other settings. If you want the Blur, do not use the Blur, but play with Rays and Angles.

LightCaps

You get a lot more control with this system.

*Turn the usual light intensity really low.

Control the LightCap

-

Aperture- makes the beam diameter smaller/ wider

Falloff- how fast the light will start to fade and lose its intensity. Sharp/ soft of the diameter

You can have the light not casting shadows- in case of imitating bouncing light

GOBO- an alpha for the light.  You can add alpha for it, then tile it and mess with Width, Scale, Blur an Orientation of it.

For the setting of Diffuse and Spec - you can control the separately and control opacity and all that stuff...

Diffuse

Specular

HDRI Img Lighting

You can create Lighting from HDRI. Creates img, that looks scpherical  and wraps around as an environment.

Background-> turn On Img-Import -> Turn on the big LightCaps button, so it creates the light from the HDRI Img and has it effect the Sculpt.
Click the Rotate with object for the img not to rotate with the object. Use Longitude to rotate the img.

To have shadows on the floor, turn On the Floor.

If you want, you can turn off the Background and it will still have the light affecting the object.

http://www.hdrlabs.com/gallery/index.html
free HDRIs...



 

Material

-2 Types of Materials in ZBrush-


Standart Material
MatCap - the lighting is already BAKED in the material and the lighting you are trying to create will not effect it in any way.






Use  Standart materials when you start messing with lights.


*Skin Shade -> switch to it when you paint. As you sculpt, it is not the best one cause it wont reflect the lights and shadows that well and will appear really flat.
*Toy Plastic for Eyes


You can assign different Materials to Different Subtools as well as different materials to one subtool.




To assign Material to a separate Subtool, select the subtool-> switch to M at the top, turn off the RGB -> select the material that you want for the subtool-> Color- Fill Object


MRGB- color+material
RGB- color
M- material


Do Not have Eyes and Teeth and anything else the same material. When you change material, it changes material on all subtools that don't have the materials assign to it. After you fill a subtool with a material, it wont switch material every time you change it for other subtools.


If it is all one subtool, have only the thing you want to fill visible. Hide other things.
Mask stuff you don't want to have the material assigned to.


To paint some different material, turn on M or MRGB (will paint material and color at the same time) aaand paint it! Tada
But if you want lets say blur the edge, you can only do that as the Global change in Render settings- it will show the blur btw materials when you render. The higher the resolution, the less riggid the material edge will look.
Render Properties-> Materials Blend Radius- blur Materials on one Subtool together  ( pixels).




AO


( ambient occlusion) -looks for spots, where light cant get and makes it dark. Just shadows cant do that.

- shadows on ------ ambient occlusion on

 

BPR AO

- put resolution the same,as you have in shadows


Rays
Andle...all the same stuff


Gamma setting - controls transition from lights to darks. When its too low- more darks, higher -> more lights.


in the Render Passes it will show you all the maps, that were generated for the render. You can export it to Photoshop and mess with it in Photoshop if you want.




Transparency
Display Properties-> BPR Settings-> Visibility //Transparency//....
turn on the button BPR Transparent Shading, say yes when it asks you  that you don't have the Transparency on in the BPR Renders.


Transparency
- Mesh Normal
-Color


BPR Transparency


Strength- controls the Mesh Normal. Looks at camera= 100% transparent. If you change it, it will get slightly more foggy.
Color- looks at color info. Pure Black= 100% transparent, White= opaque. You can use paint!




Refract and RFactor don't work.

Some amazing ZBrush Renders.......

http://www.zbrushcentral.com/zbc-user-gallery.php?uid=84824

 

 

 

 

 

 

 

 

https://www.artstation.com/artwork/JbakR

Movement!

Rembrandt Bugatti