How to Stylize and Model 'Toon Humans - Chapter 3: Materials and Lighting

Introduction

Welcome to the third and final chapter of this series. In this chapter we will deal with lighting, materials, render and a bit of post-production. In this tutorial we will use V-Ray as the render engine instead of mental ray, which was used in the Toon Animal series. You will notice that V-Ray uses a completely different relation between values and glossiness compared to mental ray, so when we create the glossiness textures we will be using different color values.

Light Considerations

In the Animal Toon series I referred to the benefits of working with lights that behave in a physically correct manner. In order to achieve this we have to introduce a gamma correction and work with lights that decay correctly (at the inverse square of the distance).

When the light decays at the inverse square of the distance, the light is very intense near the origin, but it will lose intensity quite fast, even though it will keep traveling a long way with a very low intensity. This means that a little difference in the distance from the light to the object can greatly affect the results. In the tutorial I will provide images to help with the light positioning, but you will need to fine-tune that distance by rendering and deciding on what looks good.

Gamma Correction

Let's correct the gamma for V-Ray (Fig.01).

Fig.01

Fig.01

- In 3ds Max, inside the Customize menu choose Preferences.
- In the Preference Settings window choose the Gamma and LUT tab.
- Turn on the Enable Gamma/LUT Correction.
- Make sure the Gamma value is 2.2.
- Turn on Affect Color Selectors and Affect Material Editor.
- Set the Input Gamma value to 2.2 and the Output Gamma to 1.0.
- Press OK.

Set V-Ray

- In 3ds Max press F10 to enter Render Setup.
- Under the Common tab, disable Rendered Frame Window as we will be using V-Ray's Frame Buffer instead.
- In the Assign Renderer section click on the "..." button in front of the Production renderer.
- Choose V-Ray Adv 1.50.SP5 (my version of V-Ray is1.50 SP5, you might have a different one).
- Choose the V-Ray tab at the top.
- Under V-Ray Frame buffer, enable Enable built-in Frame Buffer.
- Under V-Ray: Image sampler (Antialiasing), change the image sampler to Adaptive DMC and the Antialiasing filter to Mitchell-Netravalli. These are just a matter of personal preference in order to increase visual sharpness.
- In the V-Ray Color mapping section set the Type to Gamma correction and set the Gamma value to 2.2 (Fig.02).

Fig.02

Fig.02

Image proportion and Camera

Let's set the image proportions.

- Press F10 to open the Render Setup window.
- In the Common > Output Size, set the Width value to 583 and the Height value to 1000 pixels.
- Close the Render Setup window by pressing F10 again.
- Choose one of the viewports to be the camera viewport and press Shift + F to show the safe frame. This way the viewport will be cropped with the same proportion of your image render.

To create the camera:

- From the Create tab on the right side panel, choose the Camera icon.
- Choose the Target button (to create a target camera).
- On the Top viewport click and drag to place the camera.
- On the viewport that you have chosen to display the camera, press C in order to see the camera view restricted by the safe frame.
- Use the Top, Left and Front viewports to select and move the camera. If you wish to follow my point of view try to place it as in the image. I have tried to position the camera in order to preserve the character's silhouette (notice how the hand is not overlapping the body) and to ensure some eye contact between the character and the viewer.
- I have set the lens value to 76 mm under the camera parameters (Fig.03).

Fig.03

Fig.03

Base Material

Before starting the lighting, create a simple box as a ground plane (Fig.04).

Fig.04

Fig.04

Let's also create a simple gray material to apply to the whole scene to study the light:

- Press M to open the Material Editor.
- Choose one material slot.
- Click on the Standard button to choose a different type of material.
- From the Materials list, under V-Ray Adv 1.50.SP5, pick the VRayMtl shader.
- Name the material as "base".
- Set the Diffuse color to R:128,G:128 B:128 by clicking the color swatch.
- Change the Reflect color to R:23, G:23 B:23 by clicking the color swatch.
- Change the Refl. glossiness value to 0.6 to add a bit of specular.
- Under the Options menu, disable the Trace Reflections option, so that no reflections will be calculated.
- Apply the material to all the objects in the scene (Ctrl + A to select all and press the Assign Material to Selection button).

Main Light

If you have a good graphics card, 3ds Max has the option of seeing the shadows in real-time in the viewport. It is a good option to set the light direction fast without the need to render (Fig.05).

Fig.05

Fig.05

- In the camera viewport, on the top left, click on the word that describes the shading mode of your view port.
- Under Lighting and Shadows, enable Enable Hardware Shading and Enable Shadows.

We will start the lighting by creating our main light source. I had imagined my character standing under a street lamp, so I have decided to create a V-Ray Light with soft shadows coming from the top right of the image, leaving the left side of the character in the shadow.

- From the Create menu on the right, click on the Light icon.
- Change the light from Photometric to V-Ray.
- Click on VRayLight and drag the viewport to create an area light.
- Try to position it as in Fig.05.
- In the VRayLight options, change the Multiplier value to 15.
- Leave the color as pure white.
- I have set the Half-length size to 0.55m and the Half-width to 0.60m.
- I have increased the Sampling Subdivisions to 12 to reduce the noise a bit.
- Render (F9) and adjust the position and intensity.

Rim Light 1

As the left side of the character is in the shadow, we will create a rim light so that the full silhouette of his body is readable. I have chosen a cool turquoise color to bring some color in and I have tried to position the light in order to leave a bit of darkness between the main light and the rim light to add some "darkness" to the character (Fig.06).

Fig.06

Fig.06

- From the Create menu on the right, click on the Light icon.
- Change the light to Standard.
- Create a Target Spot light.
- Place it on the left side of the image coming from the back of the character.
- Enable Shadows and change the shadow type from Shadow Map to VRayShadow.
- In the Intensity/Color/Attenuation menu, change the Multiplier to 50.
- Set the light color to light turquoise (R:94, G:167, B:156).
- Change the Decay Type to Inverse Square.
- Change the Start distance to 0.3m.
- In the Spotlight Parameters, set the Hotspot to 43 and the Falloff to 66.9.
- In the VRay Shadows parameters, enable Area shadow and set the U, V and W size to 0.1m.
- Press F9 to render and adjust.

Rim Light 2

To add a bit more drama to the image let's place a warmer rim light on the right (Fig.07).

Fig.07

Fig.07

- Create another Target Spot light.
- Place it on the left side of the image, coming from the back of the character (as in the image).
- Enable Shadows and change the shadow type to VRayShadow.
- In the Intensity/Color/Attenuation menu change the Multiplier to 110.
- Set the light color to light yellow (R:255, G:231, B:168).
- Change the Decay Type to Inverse Square.
- Change the Start distance to 0.3m.
- In the Spotlight Parameters, set the Hotspot to 43 and the Falloff to 66.9.
- In the VRayShadows parameters, enable Area shadow and set the U, V and W size to 0.1m.
- Press F9 to render and adjust.

Ambient Light

In order to fill the black areas, we will create a global dark blue light. It is not a good idea to have completely black areas, because you will never be able to manipulate those image areas in post-production (Fig.08).

Fig.08

Fig.08

- Open the Environment and Effects window (press 8).
- Set the background color to a dark blue (R:1, G:3, B:6).
- Open the Render Setup window (press F10).
- Under the V-Ray tab > V-Ray Environment, enable the GI Environment (skylight) override.
- Set the color to a dark blue (R:1, G:3, B:6).

Later, if needed, you can use the Multiplier value to manipulate this light.

- Change to the Indirect Illumination tab.
- Under V-Ray: Indirect Illumination (GI) tick On to turn on the GI.
- Leave the Primary bounces as Irradiance map and change the Secondary bounces to Light cache.
- Under Irradiance Map, change the Current preset to Custom.
- Set the Min rate to -3 and the Max rate to -1.
- Don't change the Light cache parameters.
- Press F9 to render.

Eyes Material 1

Let's start by creating the cornea material. In this tutorial I have used a fairly simple eye model; if you have followed the animal cartoon tutorial you can re-use the more complex eye model we created there (Fig.09).

Fig.09

Fig.09

- Open the Material Editor (press M).
- Choose a Material Editor slot and press the Standard button. Choose VRayMtl under V-Ray Adv 1.50.SP5.
- Under Reflection, change the Reflect color to white (R:255, G:255, B:255).
- Press the "L" button in front of the Highlight glossiness to unlock and be able to use specular highlights which have independent glossiness values from the Reflection glossiness.
- Set the Highlight glossiness value to 0.9. This will create a little specular highlight.
- Turn on Fresnel reflections.
- Under Refraction, change the Refract color to white (R:255, G:255, B:255).
- Change the IOR value to 2.0. This value not only affects the refraction distortion but also the effect of Fresnel reflections.
- Enable Affect shadows in order for the refraction to affect the shadows and make them transparent, otherwise the shadows will be opaque.
- Select the cornea objects and apply the material by pressing the Assign Material to Selection button.
- Render.
In the image I have isolated the eyes in order to be clear what we are doing.

Eyes Material 2

To create the eye material we will use the VRayFastSSS2 material. Subsurface scattering is important to recreate the white of the eye (Fig.10).

Fig.10

Fig.10

- Open the Material Editor (press M).
- Choose a Material Editor slot and press the Standard button. Choose VRayFastSSS2.
- Under General Parameters change the preset to Milk (whole). We will use this preset because the color and settings are very near to what we need.
- Increase the pre-pass rate to 0.
- Under Diffuse and sub-surface scattering layers, change the diffuse amount to 1.0 and decrease the scatter radius to 1.
- Under Specular layer change the specular glossiness to 0.5 and turn on trace reflections.
- Under Maps place the "eye_diffuse.PSD" in the diffuse color slot.
- Select the eye objects and apply the material.
- Render.

Eye's Highlights 1

We will create some highlights on the eyes and make the lower part of the iris brighter by using a spotlight without shadows and only including the eyes (Fig.11).
- From the Create menu on the right, click on the Light icon.
- Change the light to Standard.
- Create a Target Spot light.
- Place it coming a bit from above and from the right of the image, hitting the lower part of the iris. The objective is to create a highlight at the upper right part of the cornea and another at the lower left part of the iris.
- Make sure the Shadows are off.
- Press the Include button and from the left list choose the eye and cornea objects. Press the ">>" button to move these objects to the inclusion list. This way only these objects will receive light. Press OK.
- In the Intensity/Color/Attenuation section change the Multiplier to 0.18.
- Set the light color to white (R:255, G:255, B:255).
- In Spotlight Parameters, set the Hotspot to 0.8 and the Falloff to 2.8.
- Copy the light and position it to hit the other eye in the same way.
- Press F9 to render and adjust.

Fig.11

Fig.11

Eye's Highlights 2

In order to further enhance the reflections, create a light box that will show up in the eye's reflections (as in a photography studio). Let's start by creating a self illuminated material for the light box (Fig.12).

Fig.12

Fig.12

- Open the Material Editor (press M).
- Choose a Material Editor slot and press the Standard button. Choose VRayLightMtl.
- Leave the color as white.
- Change the intensity value to 0.6.
- Create a Box primitive with a length of 0.25m, width of 2.0m and height of 4.0m.
- Apply the material to the box.
- Right click on the box object and choose VRay properties.
- In the VRay object properties, disable Generate GI and Receive GI. We don't want the box to illuminate the scene, but just to enhance the reflection highlights. So we are disabling the GI.
- Position the box as in Fig.12 (my box is about 6 meters away from the character).
- Render and adjust the box position in order to create highlights on the eyes.

Skin Material 1

Before creating the skin material we need to create some more textures. To create the texture that will control the glossiness amount on the skin we will use the cavity texture as a base (Fig.13).

Fig.13

Fig.13

- Open Photoshop.
- Open the "body_cavity.PSD" image generated in ZBrush during Chapter 2.
- To tone down the values, create a new layer
on top and fill it with a mid gray color (R:128, G:128, B:128). Change this layer's opacity to 55%.

As explained in the Toon Animal tutorial, you can check the values of the image by keeping the Info window open (press F8) and setting the displayed color to HSB. As you move the cursor over the image, the B value (brightness) indicates the glossiness percentage of that pixel.

- Create a new layer on top. Select the brush tool (B) and set the brush opacity to 5%.
- To increase the glossiness percentage paint with white, to decrease it paint it black. While you paint keep checking the B value on the Info window. The idea is to set the correct percentages in each body area.
- I have used this technique to make the lips, interior of the ears, forehead, tip of the nose and nails glossier. In Fig.13 I have marked a few values that you can use as reference.
- On top of everything, create a new layer. Fill it with a gray color (R:128, G:128, B:128).
- From the Filter menu choose Add Noise from the Noise sub menu.
- Set the Amount to 40%, Uniform distribution and turn on Monochromatic.
- Set the layer mode to Overlay and the Fill value to 34%.
- Save it as "body_glossiness.PSD".

Skin Material 2

We will create a noise map to work as a specular map and break the highlight reflections. You could also create a procedural map for this effect as an alternative in 3ds Max (Fig.14).

Fig.14

Fig.14

- Create a new document with 4096x4096
pixels.
- Fill the document with a light gray (R:202, G:202,B:202).
- From the Filter menu choose Add Noise from the Noise sub menu.
- Set the Amount to 25%, Uniform distribution and turn on Monochromatic.
- Save it as "body_specular.PSD".

Skin Material 3

With the "body_specular" and "body_glossiness" textures created in the previous step, along with the "body_epidermal" and "body_subdermal" textures created in the second chapter, we will set up the skin material (Fig.15).
- Open the Material Editor (press M).
- Choose a Material Editor slot and press the Standard button. Choose VRayFastSSS2.
- Under General Parameters change the preset to Skin (pink).
- Increase the pre-pass rate to 0.
- Under Diffuse and sub-surface scattering layers, change the diffuse amount to 0.65, change the scatter color to R:89 G:23 B:10. Also change the scatter radius to 1.6cm.
- Under Specular layer, change the specular color to a very light blue (R:214 G:255 B:255). Increase specular subdivisions to 10. Turn on trace reflections and lower the reflection depth to 3.
- Under Options, increase the single scatter subdivisions to 12.
- Under Maps place the "body_diffuse.PSD" in the diffuse color slot.
- Place the "body_specular.PSD" in the specular amount slot.
- Place the "body_glossiness.PSD" in the specular glossiness slot.
- Place the "body_subdermal.PSD" in the sss color slot.
- Select the body object and apply the material.
- Render.

Fig.15

Fig.15

Trousers Material 1

Let's create the material for the trousers (Fig.16).

Fig.16

Fig.16

- Open the Material Editor.
- Choose a Material Editor slot and press the Standard button. Choose VRayMtl under V-Ray Adv 1.50.SP5.
- Under Reflection, change the Reflect color to gray (R:108, G:108, B:108).
- Set the Refl. glossiness value to 0.45.
- Turn on Fresnel reflections.
- Lower the Max depth to 1 to speed up the render time as inter reflections are not very noticeable with this glossiness values.
- Under Maps click on the Diffuse slot and from Maps/Standard pick Falloff.
- Click Falloff to set its parameters.
- In Falloff Parameters, in the Front: Side section, place the "trousers_diffuse.PSD" created in Chapter 2 in the upper slot.
- In the lower slot, click the color swatch and set it to a light blue (R:137, G:165, B:199).
- There is a Mix Curve at the bottom. Manipulate it in order for the light blue to only appear at grazing angles (you can check the curve in Fig.16).
- Select the trousers object and apply the material.
- Render.

Trousers Material 2

If you remember, in Chapter 2 we placed some trouser straps in the trousers texture. It is time to apply this texture and set the UVs to the straps (Fig.17).

Fig.17

Fig.17

- Select all the trouser straps and apply them the same trousers material we have created in the previous step.
- Select one of the straps.
- Apply an Unwrap UVW modifier.
- Press Edit.
- Click the Pick texture slot on the upper right and choose the Falloff map. This way you'll be able to see the trousers texture on the background to align the UV coordinates.
- To display the texture with a higher resolution, click on the Option button and under Bitmap Options set the Width and Height to 2048, for example.
- As we had turned on the Generate UVs option in the Sweep modifier, the texture coordinates of the strap have a nice rectangular form, exposing the back and front of the strap.
- Select the strap element and rotate and scale it to align with the image strap.
- Repeat the procedure for all the straps.

Belt Material 1

To create the belt material we need to create another texture which will be used as bump and glossiness map (Fig.18).

- In Photoshop, open the "belt_diffuse.PSD" image created in Chapter 2.
- When we created the belt texture, the holes were placed in different layer. Select the layer of the belt without the holes.
- Desaturate the image (press Shift + Ctrl + U).
- Choose Image/Adjustments/Brightness Contrast.
- Set the Brightness to 50 and the Contrast to 50.
- Desaturate the holes too.

Fig.18

Fig.18

If you have previously merged the belt holes with the belt, don't worry. Apply all the adjustments and paint the holes black.
- Save as "belt_glossiness.PSD".

Belt Material 2

To create the belt material in 3ds Max (Fig.19):

- Open the Material Editor.
- Choose a Material Editor slot and press the Standard button. Choose VRayMtl under V-Ray Adv 1.50.SP5.
- Under Reflection, change the Reflect color to gray (R:181, G:181, B:181).
- Set the Reflection glossiness value to 0.6.
- Turn on Fresnel reflections.
- Lower the Max depth to 2.
- Under Maps, place "belt_diffuse.PSD" in the Diffuse slot.
- Place the "belt_glossiness.PSD" in the Reflect, RGlossiness and Bump slots.
- Select the belt object and apply the material.
- Apply the same material to the leather straps. As for the trousers straps, use the Unwrap UVW modifier to scale and move the UV coordinates to align them with a part of the belt texture that doesn't have holes.
- Render.

Fig.19

Fig.19

Belt Material 3

For the metallic parts of the belt we will create a simple metal material (Fig.20).
- Open the Material Editor.
- Choose a Material Editor slot and press the Standard button. Choose VRayMtl under V-Ray Adv 1.50.SP5.
- Change the Diffuse color to dark gray (R:11, G:11, B:11)
- Under Reflection, change the Reflect color to a light gray (R:137, G:137, B:137).
- Set the Reflection glossiness value to 0.7.
- Turn on Fresnel reflections.
- Lower the Max depth to 3.
- Under Refraction, set the IOR value to 30.
- Apply the material to the buckle, pins and tip of the belt.
- Render.

Fig.20

Fig.20

Boots Material 1

We will create a glossiness texture for the boots, based on the diffuse texture created in Chapter 2 (Fig.21).
- Open "boots_diffuse.PSD" in Photoshop.
- When we created this texture we started with a cavity map in Overlay mode, added some textured color layers below created layers on top of that with scratches and dirt.
- Don't touch the cavity layer and the scratch and dirt layers.
- Select each texture color layer below the cavity map layer and desaturate them (Shift + Ctrl + U). In each layer shift the Brightness and Contrast values up in order to have an average pixel value of about 60-65% (Check the B value of the HSB in the Info panel). I have marked some values on the image for your reference.
- Save as "boots_glossiness.PSD".

Fig.21

Fig.21

Boots Material 2

To create the boot material in 3ds Max (Fig.22):

- Open the Material Editor.
- Choose a Material Editor slot and press the Standard button. Choose VRayMtl under V-Ray Adv 1.50.SP5.
- Under Reflection, change the Reflect color to gray (R:155, G:155, B:155).
- Set the Reflection glossiness value to 0.65.
- Turn on Fresnel reflections.
- Lower the Max depth to 1.
- Under Maps, place "boots_diffuse.PSD" in the Diffuse slot.
- Place the "boots_glossiness.PSD" in the RGlossiness slot.
- Select the boots objects and apply the material.
- Render.

Fig.22

Fig.22

Completing the environment

To complete the environment I have added a pole with a sign and an old cigarette prop. These were made with simple primitives. The pavement was also given a broken asphalt texture. As these are just environment props, their creation is not going to be detailed, however, in Fig.23 you can see all the maps that were created to make the materials. All the materials use the VRayMtl shader and follow the same logic as the materials we created during the rest of the tutorial (Fig.23).

Fig.23

Fig.23

Rendering

I have rendered the final image with 5000 pixels of height. I will share with you the render settings I have used (Fig.24).
- Press F10 to open the Render Setup window.
- In the Common, tab under Output Size, click the lock icon in front of Image Aspect. That will keep the image proportion when you change the width or height of the image. Change the output to 5000 pixels of height.
- In Render Output, enable Save File and set a file name and destination for the image. Choose a lossless format like TIF.
- In the V-Ray tab, in the V-Ray: Adaptive DMC image sampler section, increase the Min subdivisions to 2 and the Max subdivisions to 6.
- In the Indirect Illumination tab, in the V-Ray:Irradiance map section, set the Min rate to -4 and the Max rate to -1. In the V-Ray:Light Cache section increase the Subdivisions to 2000 and set the sample size to 0.01.
- We will also need to render a ZDepth image to use in the final composition. Choose the Render Elements tab and click the Add button. From the list pick VRayZDepth.
- Set the file name and location to save the VRayZDepth file. Use a 16 bit TIF format to have a richer grayscale gradient.
- In the VRayZDepth parameters I have set the ZDepth min to 2.0m and the ZDepth max to 10.0m.
- Render.

Fig.24

Fig.24

ZDepth

We will now start the post-production phase (Fig.25). The reason for rendering the ZDepth channel is to create a soft transition between the floor and the background color:

- Open the ZDepth image in Photoshop.
- Press Ctrl + L to open the Levels Adjustment window. Set the Min input level to 57 and the Max level to 165. Your values might be slightly different, but the objective is to have a completely white character and a gradient that starts near the character's feet and ends at the floor limit. Check Fig.25 to see what we are after.
- Select All (Ctrl + A) and Copy (Ctrl + C) to copy the image to the buffer.

Fig.25

Fig.25

Composition 1

- Open the render image.
- Open the Channels window (Go to the Window menu and choose Channels).
- In the Channels window, click on the icon on the top right and choose New Channel.
- Press Ctrl + V to paste the Zbuffer image into this channel.
- Ctrl + Click on the name of the Channel you have just created to make a selection.
- To see the original image, press the RGB channel.
- Go to the Layers window.
- Create a new layer on top of the background.
- Go to the Layer menu at the top bar and under Layer Mask choose Hide Selection. You have just created a mask for the layer.
- In the selected layer, in the Layers window, you have two little thumbnails: one for the image and another one for the mask. Click on the image thumbnail (which is empty) to paint on the image instead of on the mask.
- Using the color picker, pick the blue color of the background.
- With the bucket tool (press G), fill the layer with the blue color. We now have a smooth gradient blending the floor and the background color (Fig.26).

Fig.26

Fig.26

Composition 2

Apply a Levels Adjustment layer and adjust the levels by raising the Min input level and lowering the Max input level to get more contrast in the image and make it more appealing. The values depend on your image. My image was a bit dark so I have raised the Min input to 13, set the Mid input to 0.95 and lowered the Max input to 128.
As there is some light coming from above, I have created a gradient to fake the light scattering in the atmosphere. To do this create a new layer (use the same mask as before if you don't want to include the character in the light) and create a light yellow gradient. Set the layer mode to Color Dodge and a fill rate of 50% (Fig.27).

Fig.27

Fig.27

Composition 3

To create the smoke coming out of the cigarette I have used some smoke images against a black background. I have placed the smoke images in new layers and used the Screen blending mode to integrate the smoke with the background. Use the Fill value to adjust the smoke transparency. Also use the eraser with a soft brush to shape the smoke (Fig.28).

Fig.28

Fig.28

Conclusion

This ends the image composition and also this tutorial (Fig.29).

Fig.29

Fig.29

I hope you have enjoyed the tutorial and that you have created a great character and learned some new tricks. Feel free to drop me an e-mail if you need any clarification! See ya!

To see more by Jose Alves da Silva, check out Digital Art Masters: Volume 9 and ZBrush Character Sculpting