Arvid Schneider is an awesome guy that creates extremely high quality tutorials. Check out his website and Youtube Channel. He made a great tutorial on how to create Captain America’s shield, teaching a thing or two about anisotropy.
He covers a lot of topics in a very short time. I had some difficulties to follow a couple of his steps. So here is a rewrite of the tutorial with my personal preferred way of doing things. However definatly go check out the video, he describes the steps in much greater detail.
Part 1: Modeling the shield
I am going to be using a Poly Sphere to create the shield.
Create a Poly Sphere. In faces mode select the lower part of the ball.
(If you selected a little more than the half re-position the Pivot Point)
Scale the half-sphere down.
RotateZ = 90
Create a UV-Layout. The important thing is, since in the tutorial a lot of ramps with the circular attribute are going to be used that the center of the UVs are placed exactly in the middle.
The easiest way to get a perfect placement is to use “UV > Planar”, and Project from the X-Axis.
Part 2: Initial Render Setup
Step 1: Camera
Create a Render_Cam (**Create > Camera > Camera**)
**Panels > Look through Selected**
**View > Camera Settings > Resolution Gate**
Position the Camera
Initially I set up the camera just like in the tutorial with the shield slightly slanted. This setup has the benefit that you can clearly see the reflections.
For the final image I chose to re-position the camera for a more frontal view of the shield.
Step 2: Lighting
Arvid Schneider does not go into his lighting Setup, in essence he has a “Studio Lighting” and a “Outdoor Lighting” HDR setup.
I only used a basic Studio Lighting with the help of two Area Lights, (Exposure 12, and Exposure 17)
Part 3: The Shader
Arvid Schneider recommends to connect the newly created ramp into the diffuse color attribute, so you can immediately see the color output
Step 1: alShader
Create a new alShader “al_shield” and assign it to the shield.
Step 2: Base Colors + Star
In the Hypershade editor press Tab and create a new “ramp (texture)” (base_color), connect it directly to the diffuse color of the alShader.
Change the Type to “Circular Ramp” and the Interpolation to “None”
In the Attribute Editor adjust the colors of the gradient:
Use a reference image of the shield, and the Arnold Renderview to determine how wide the various segments of the gradient need to be.
To add the star, first google for a star image. (The star should be white, if not you should edit it in Photoshop)
In the Hypershade create a “aiCombineColor” Node, Change the Combine Op to add 1+2.
Connect the ramp “base_color” to input1 and “out color” to “al_shield” Diffuse Color.
Create an aiImage Node, import the star and connect it to input 2.
Change Wrap U and Wrap V to file, to ensure that you only have a single star.
With Scale U and Scale V, you can make the star bigger or smaller (larger numbers make the star smaller, smaller numbers makes the star bigger)
Finally position the star using the Offset U and Offset V Attributes.
If everything is looking good, break the connection to the “diffuse color” and connect the aiCombineColor1 to the Specular 2 Edge Tint and to the Specular Color 2 Reflectivity.
Set the Strength of Reflectivity 2 to 1 and the Fresnel Mode to metallic.
Step 3: Ansiotropic Map
The Ansiotropic Map is going to be used as a bumpmap, and should simulate the small ridges in the surface.
In the Hypershade create a “ramp (Texture)”, name it ramp1. (Make it Type Circular)
Open the Script Editor (python) and use following code to create a ramp with many many small ridges.
Autodesk officially only supports Fedora/RedHat. This is probably due to legacy reasons, since larger Corporations were using RedHat. There is an official documentation how to install Maya on Fedora link
However Ubuntu (based on Debian) has become very popular. (As Alternative you also could use Elementary, Mint etc.) We will take a look on how to install Maya 2017 (Student Version) on Ubuntu via the Command Line.
This technique is a very quick and dirty approach to creating a pile of stuff. The downside using this technique is due to the fact that particles are generally round and usually stuff is not round, causing segments of your geometry to intersect with other objects.
Set up a nParticle emitter: In the FX Menu select nParticles > Create Emitter
Adjust the following Attributes of the emitter1:
TranslateY = 9
Rate (Particles / Sec) = 20
Configure the nParticle (“nParticleShape1”) Shape –
Self Collide = true
Stickiness = 1.0
Aactivate the ground plane in “nucleus1”. This will create an invisible plane to collide with the particles.
UsePlane = true
Alternatively you could create a poly plane as ground plane to be used as a particle collider.
Set the Playback Range to 1-500 and view how the Particles are piling up.
You can switch the Particle Render Type to Spheres to get a better idea of how the Pile will look like.
Adjust the particle & emitter settings to fit your needs.
I created a couple of basic objects, that I will use instead of the Particles.
Select the particles and all the objects you want to use as geometry replacement. nParticles > Instancer
Now all the Particles should look like the first object in you selected. (in my case cubes)
Select the Particles again go to Add Dynamic Attributes and click the General Button.
In the Add Attribute dialog enter for the Long name = objIndex PP, enable Per particle(array) and click Ok
Back in the ParticlesShape Node open “Per Particle (Array) Attributes” RMB on “Obj Index PP” > Creation Expression
In the Dialog add following Expression:
In essence this means that for each particle a random number between 0 and 3 is going to be choosen.
Back in the Attribute Editor go to Instancer(Geometry Replacement) > General Options > Object Index select ObjIndex PP
Restart the playback to refresh all particles.
(optional) Step 10
Now all the objects are looking kind of stacked up and look identical. To make it visually more interesting you can activate “Rotation“.
Go to Instancer(Geometry Replacement) > Rotation Options > Rotation and select rotationPP
You can modify and place your initial geometry on its own layer and hide that. (Especially if your objects appear to big, you could scale them down etc.)
If you want to show off your awesome modelling skills, there is no better way then to show off the models wireframe. You could do a quick screenshot of your model in wireframe mode, but that looks cheap and not very impressive. It would be better to render the object using a render engine.
I will show you how you can make a clean, technical and awesome looking image using mental rays “contour” render option. To use this feature you have to activate it in the render settings and then apply a shader to the object. This way you can set up an environment that is rendered normally and your hero object is rendered as wireframe object.
You probably neither have seen or heard of this feature due to that this feature is only found in the “legacy mode” of Mental Ray and even then it is still hidden in the advanced settings.
Set “Render Using” to “mental ray”
Open the “Quality”-tab
Enable “Show Advanced Settings“
Expand “Legacy Options“> Set Sampling Mode to “Legacy Sampling Mode”
Expand the “Draw by Property Difference”-section > Enable “Around all Poly Faces”
First create a white Lambert material “mat_wireframe”
Navigate to the Shading Group “lambert2SG”, and rename it to“mat_wireframeSG”
Expand the mental ray section, and the subsection “Contours”
Enable “Contour rendering”, and set the color to black.
Apply the material to a test object (like a poly sphere) and do a render.
If necessary adjust the value of the width (0.5 usually has nice results)
Now apply the material to the objects that you would like to render as wireframe.
Note: if you render objects with “smooth mesh preview” enabled (By pressing the Key 3), mental ray renders a more complex wireframe. In such cases selecting the object and pressing the key 1 enables mental ray to render out the low poly version.
The IES (Illumination Engineering Society) standard format file stores information about the distribution of light from a real light source. Profiles are created by measuring light bulbs in the real world.
Now that sounds quite boring, wouldn’t the light profiles be exactly the same as a normal CG light? Well, it really depends on the physical attributes of the lightbulb. For example many halogen lightbulbs have small reflectors in them causing the light to have very characteristic hotsposts.
We are going to take a look at how to use these profiles with Mental Ray and Arnold.
Where to get IES Files?
Most of these profiles are available for free on the light manufacturers websites.
For an university assignment I had to “display” my modelling progress. My instructor wanted me to do a screenshot every 60 seconds. However he was not impressed by the result. He wanted to see real renders.
To avoid interrupting my work every 60 seconds I enabled the internal “autosave” feature. Then of course I ended up with a ton of files. But now I still needed to render out every single file, so I created a simple script to render all files in the folder.
This Python script will create a batchfile which when exectuted will render every single file.
We will be taking a look at how you can light your scene using the “infinite white background” look. This look is commonly used to present technical stuff or single objects.
In my example I am going to use a model of a dragon statue. First we will be taking a look at how to achieve the effect using only Final Gathering and after that we will take a look at using ambient occlusion as a light source.
Create a Poly Plane with a white lambert and import your object.
Create a Camera. Set the Environment> Background Color to White
For the Final Gather technique we will not use any lights. The default light would only cause unwanted side effects.
To disable the “default light”, open the Render Settings in the “Common” tab open the panel “Render Options” and remove the check at “Enable Default light”.
The Final Gather Effect will use the environment color of the camera to light the scene. You only need to activate Final Gather and you will see the result.
Ambient Occlusion Light Source
Create an Area Light. In the Attribute Editor under mental ray > Area light, activate Use Light Shape.
Connect to the Attribute “Custom Shaders > “Light Shader” a “mib_amb_occlusion” node.
Step 3 (optional)
To increase the render quality you can adjust the attributes “Samples” and “Max Distance“.
By default you select faces in Maya with the whole face. I recommend changing this setting to “Center”. It makes it easier to select faces in the orthographic views and makes faces without area visible.
To change the setting go to Window > Setting & Preferences > Preferences, on the left choose “Selection” and choose “Select Faces with: Center“.