Gustavo Rios reveals how he created the inventive cover image for issue 159 of 3D World
Gustavo Rios used Hair & Fur to create the boy’s hair, the bear and the grass
Artist Gustavo Rios
Title Aim for the Stars
Software 3ds Max, ZBrush, Photoshop, Vue
“I always wanted to make a ‘storytelling’ illustration, so when I had the idea for this image, I picked up a piece of paper and sketched right away, because ideas can go away as fast as they come!
“In 3D you have many ways of doing the same thing. Most of the techniques I explain in this tutorial are my personal way of working, so if you know an easier way or another method you prefer to use in any of the steps, feel free to use it!
“The most important thing when making a character-based scene such as this is to work on the personality and expression. I try to see characters like they’re two-dimensional, modelling and posing for the camera.
“Read on to discover how I created this issue’s cover image using 3ds Max, ZBrush, Photoshop and Vue.”
Stage 1: Concept, composition and workflow01 Plan the scene
When making a scene I tend to make the easier things first. It helps to keep myself motivated until the end of the project. So I made the blocking of objects and camera to study the composition and see the level of detail that each object would need. With the blocks I noticed that some of the rocket detail would have to be modelled after the boy was in the scene, because he would be on top of it, and interacting with it. That meant that it would be better if the boy was rigged too.
02 Sculpt the background models
I took the rocket block I made earlier and modelled the rocket with the usual box modelling techniques. I used planes with shell modifiers to give the rocket some thickness, and I used splines to model the cables and lines. I modelled the bear in ZBrush from ZSpheres.
03 Build the character
I made a base mesh in 3ds Max with all the loops needed for sculpting. I sculpted the form and the details of the face and hands in ZBrush. The body and feet are covered by clothes and shoes, so there was no need to worry about details on these parts. To model the glasses, helmet, clothes and so on, I sent the boy body to 3ds Max, modelled the base mesh of the objects, then brought them back into ZBrush. In the beginning stages, the brushes I use the most are ClayBuild and Dam standard, to sculpt the main volumes. When refining I use Pinch and Dam standard to make sharp contours, Clay and Inflate to refine the volumes, and Polish and Smooth to polish.
After the sculpting process, I painted the skin and eye maps in ZBrush using Polypaint. It works well when painting maps that don’t have too many details, so it’s good for cartoons. To make a good skin material, I painted the diffuse, subdermal and specular maps on a different layer. I used the SkinShade4 material to paint: it’s very bright so you can see the colours better, and the results are very similar to the render.
04 Generate the textures
Before I could generate the textures, I had to do the UV mapping using UV Master in ZBrush. After that I generated the textures, then exported the model in a low subdivision and all the textures. Before the rigging I like to make the materials to correct any problems, and make sure the character will look good in the render. I used Mesh Smooth on the character skin to subdivide, and on the top of it I used a displacement modifier with the displacement map generated before. This modifier enables you to see the volumes and details in the viewport. For the skin material I used Zap’s skinplus shader.
05 Sculpt the eyes
The boy’s eyes are composed of a totally transparent and very specular hemisphere.
Set the anti-aliasing too low and the hair will look awful
06 Create the hair
I made the hair using splines with the Hair & Fur modifier applied to them. I created a straight line with a spline. In sub-object mode, I duplicated it several times to form a band of parallel stripes. I then applied the Hair & Fur modifier and positioned the splines on the character’s head. I added points to the splines to model the shape as necessary. By default the hair is too thin at the tip, so in the Hair modifier properties, I changed it to a number greater than zero and smaller than the thickness of the root. I rendered the hair using the p_HairTK shader. For the final render I used 1/16 anti-aliasing to ensure it looked good. I also made tests to see if the hair looked good in high resolution, and adjusted the hair density and hair thickness.
07 Create the hair material
In the material editor, I picked the Mental Ray material. In the Surface slot I used the p_HairTK shader, and on the Shadow slot I used p_HairTK_shadow. In hair properties on the command panel I activated Apply mr shader in mr Parameters, and dragged the material to the slot. By default p_HairTK is configured blonde, so I changed the specular colours to get the results I wanted. Finally, in the Hair Rendering Options, I chose mr prim.
08 Rig the character
CAT tools are fast, powerful and easy to use
The rig for this character won’t be used for anything other than a one-off pose, because it isn’t meant for animation. I used the CAT tools because they’re fast, powerful and easy to use, with a simple preset humanoid as a base, making sure I move the appropriate joints into position with my mesh, before I add a skin modifier to bind the elements together. When you set the skin with the CAT rig, some parts of the character won’t deform correctly. That’s because you need to paint the skin weights. The trick is that you can paint the skin weights only to the pose you need. It’s also worth working symmetrically. I used the mirror mode to help with this, and once done I adjusted any bone weight maps accordingly. Green and blue vertices mean that the symmetry was recognised; red vertices mean no symmetry was recognised. When set correctly, the symmetry shows one side blue, the other green and the centre vertices in red. The weights can be painted for this specific pose. You don’t need to worry about the mesh deforming oddly as it moves, seeing as it will never be animated. You can paint the weights on one side, then activate mirror mode again to copy to the other side.
09 Simulate and render the clothes
I used simulation to make the cloth more realistic. I used the character mesh as the Collision Object, so it had to be optimised. First, I cloned the posed character, and attached all the modifiers (including Skin and Meshsmooth). I applied a Pro-optimizer modifier to the character mesh and changed Vertex until the mesh was optimised for the simulation. I added an Edit Poly modifier to delete polygons not needed for the simulation (hands, feet, neck). I used GoZ to send a low subdivision of the cloth (shirt and pants) to 3ds Max. I generated displacement maps to use later.
Before I started simulating, I needed to deform the cloth to the character pose. I selected the CAT Rig. In Command Panel > Motion tab, I clicked Setup/Animation Mode Toggle to turn off the layers and see the default pose. I selected the cloth, and added a Skin wrap modifier. That modifier attaches one mesh to another. I clicked Add and chose the character mesh, then I clicked Setup/Animation Mode Toggle, and the cloth followed the deformed mesh. I attached the Skin Wrap modifier.
Next, I applied a Cloth modifier to the cloth mesh. In the cloth properties, in the Command Panel, I clicked Object Properties. I changed from Inactive to Cloth and chose the preset Cotton. I clicked Add Objects and selected the character mesh I optimised. Then I changed from Inactive to Collision Object. I needed some vertices of the cloth to stay static, and to do that I had to create a Group. I selected the Group sub-object of the Cloth modifier, selected the vertices I wanted to freeze and clicked Make Group. I used soft selection to have a smooth transition between the frozen group and the cloth. I clicked Preserve, then in Cloth properties I activated Self Collision and Check Intersections. Finally, I clicked in Simulate Local.
I used the same process to make the pants, then exported displacement maps of the clothes to use in 3ds Max, using displacement modifier. I wanted the shirt to have ink splashes, so I mixed two materials using Blend material. In one material I used a texture of ink splashes and used the same map to make the mask and bump.
10 Make the grass
Gustavo Rios made the grass using Hair & Fur with new properties
I used Hair & Fur to create the grass. In style mode, I did some variations with the Hair Brush and added some frizz and kink. The hair was rendered with the same techniques used for the boy’s hair, but set to have grass-like properties. Grass doesn’t have very thin tips and it isn’t curvy like hair, so in the Hair & Fur modifier properties, I adjusted the Tip Thickness and Hair Segments values. Then, in Photoshop, I used some grass pictures to do the composition with the 3D render.
11 Render the rocket
To make the metallic material of the rocket, using Arch & Design I set the material to dark grey, low diffuseness and very reflective. Some blur in the reflection helped to show the volumes and details. I used a map of scratches in the bump channel to make it more realistic. To simulate the fur on the bear, I used a Noise modifier combined with Meshsmooth to subdivide the mesh. A white falloff on the Diffuse channel helped to give the furry look.
Gustavo used the camera to match the Vue lighting in 3ds Max
12 Set up the lighting
The scene is half day, half night, so to integrate them better I placed the sun at the bottom left (like a sunset) and a big moon at the top right. I rendered a simple sky/sun/moon background in Vue, and in 3ds Max I recreated the same light conditions of the render made in Vue. (If you don’t have Vue you can use Terragen or even Photoshop.) The house in the background was curved on purpose to look like a cartoon.
I went to Create > Lights > Daylight System, and 3ds Max automatically created the sun and sky. It offered to activate exposure control automatically, and I chose No. I changed the sun properties to mr sun and mr sky. The sun was set to manual, and I positioned it looking through the camera to be in the same position as the sun in the Vue render.
I wasn’t using exposure control so I had to make a test render to see if the sky was too bright. If so, you can reduce the sky intensity value until you can see some colours in the sky. Some sky portals helped to give the blue tones in the dark areas, and spots to draw contours of objects.
13 Rendering and post-production
In Photoshop I merged the renders together, making colour and tone corrections, and adding glow and bloom effects, some mountains in the background and some birds in the sky.
The grass is a mix of 3D and photos, so for the objects in contact with the ground I had to fix the integration with the grass, masking the base and drawing additional grass with the Standard Photoshop brush. Make sure the grass you paint has the same colour and tones as the original grass.
Posted on Tuesday, August 14th, 2012 at 4:09 pm under Artwork, Features, Showcase. You can subscribe to comments. You can leave a comment, or trackback from your own site.
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