Archive for March, 2010
The “mental ray Seminar” 2010
On May 20th 2010 I will be hosting the second annual “mental ray Seminar” to be held at Moraine Valley Community College in Palos Hills, IL.
This is a free event sponsored by Autodesk, Moraine Valley Community College, 4D Artists, and Hagerman. Additional details and sponsors will be announced as the event gets closer. If you are interested in providing door prizes, please let me know via email: jenni at mastering-mentalray.com.
Registration details will follow, and registration is required for the live event. Hagerman has generously offered to provide GoToMeeting access to attendees worldwide.
The mr Seminar will be based on my book “Mastering mental ray” and we are planning on covering many highlights from the book. The meeting is tentatively scheduled to start at 8am for breakfast and networking, free lunch from 11:30 to 1, and then more seminar from 1pm to 4pm. Additional networking and socializing time ends at 5pm sharp.
Watch for more details!
New mental ray features in 3ds Max 2011
There are a few items that are new for 3ds Max 2011 and 3ds Max Design 2011 related to mental ray:
1: You can now access mental ray via string options in MAXScript. I’ll have an article talking about that in the near future, probably on the site as Bonus material.
2: Rays in Glass/Glazing will now pass through to the environment or a solid object rather than returning black. Typically, if your Refraction settings in mental ray or for that material were too low, glass objects would turn black. This is no longer the case. You do need to have enough refractions so your objects still look correct – too low and the color or refractions will not be correct – but at least your rendering will be relatively okay rather than completely ruined.
3: iray is disabled at the moment. I have no inside information, but I trust that this is a feature that will appear either as a subscription benefit or certainly if/when there is a 2012 version of Max.
4: Irradiance Particles and Importons now take advantage of Final Gather for improved results. See latest ctrl.ghost plugin page: http://www.mastering-mentalray.com/index.php?option=com_content&view=article&id=52:ctrlghost-plugins&catid=42:ctimpip&Itemid=65
5: Autodesk has added a few ‘wrapper’ shaders for mi shaders, eliminating the need to edit files to access the shaders:
- mib_blackbody is accessible as “Kelvin Temperature Color” shader,
- mia_lens_bokeh is accessible as the “Depth of Field/Bokeh” lens shader,
- mip_rayswitch_advanced is now accessible as “Utility Color Override / Ray Type Switcher”
- mia_envblur is the ”Environment Blur” shader.
6: MetaSL shaders are accessible in the new Slate material editor, and you can also export your materials to the MetaSL XML format. The MetaSL shadersthat are exposed are:
- Component Falloff
- Component Reflection
- Conversion Color to Float
- Conversion Float to Color
- Illumination Phong
- Math Color Add
- Math Color Mix
- Math Color Multiply
- Normals Bumpmap
- Normals Make Normal, and
- Texture Lookup 2d.
Autodesk also cites performance and stability improvements in what they call “mental ray 2011″, which is mental ray 3.8.
Jenni
Using mib_blackbody/Kelvin Temp Color shader and the mr Sky Portal
The mr Sky Portal can be used as a true area light when combined with a Custom color shader and by using the mental ray mib_blackbody shader. In Max 2011 there is a new shader called Kelvin Temperature Color that wraps the mib_blackbody shader and can be used directly, however in previous versions of Max you must first unhide the mib_blackbody shader in order to use it.
The advantages of the mib_blackbody/Kelvin Temperature Color shaders are that the color temperature is in Kelvin, the intensity increases as the area (portal size) increases, and it acts as a true area light. A photometric light works differently, shown on left, and is not like a true area light:
Photometric Area Light (left) vs Blackbody shader (right)
On the right is a mr Sky Portal using the Custom shader slot and the mib_blackbody shader, and at left is an area light. As you can see the photometric area light acts more like a point light with bright illumination at the center. The blackbody version has even illumination along its length and a more natural brightening in the middle. The teapot is also glowing with the mib_blackbody shader.
Before you can use mib_blackbody in Max 2010 and earlier you must first unhide the shader. However in Max 2011 there is a new shader ‘wrapper’ for blackbody called “Kelvin Temperature Color” that you can use directly. Below is the new shader shown in the Custom shader slot of the mrSP:
In 3ds Max 2010 and older, advanced users can enable additional shaders to use with the mr Sky Portal by editing both the [B]base.mi[/B] and [B]base_max.mi[/B] files in Notepad.
The files are located in the:
c:\Program Files\Autodesk\3ds Max 2010\mentalray\shaders_standard\include
…folder on a typical 3ds Max installation.
In base_max.mi, find the text gui_mib_cie_d, and place a hash mark (#) in front of the hidden declarations for that item and the next, the giu_mib_blackbody. The section should look like this (extra spaces and tabs are missing it seems):
gui “gui_mib_cie_d” {
control “Global” “Global” (
# “hidden”
)
}
gui “gui_mib_blackbody” {
control “Global” “Global” (
# “hidden”
)
}
In the base.mi file, find the text Light utils, and add a comma, a space, and the word texture after the words apply light in two locations. It should now look like this:
.
#——————————————– Light utils
declare shader
color “mib_cie_d” (
scalar ”temperature”,
scalar ”intensity”
)
version 1
apply light, texture
end declare
declare shader
color “mib_blackbody” (
scalar ”temperature”,
scalar ”intensity”
)
version 1
apply light, texture
end declare
Restart 3ds Max to accept the changes. For the Custom Color Source in the mrSP, you can now choose the mib_blackbody (or mib_cie_d shaders if also unhidden) to provide you with controls for color in Kelvin and intensity in lux (candela per meter squared). You must first drag the map from the command panel to the Material Editor in order to edit the settings. The smallest color value for the blackbody shader is 1000K.
You can find more information on using the mib_blackbody and Kelvin Temperature Color shaders in Chapter 3 of “Mastering mental ray”.
Jenni
“Mastering mental ray” Table of Contents now online
To give you a better idea of the contents of the book I have now placed the final PDF file of the book’s Table of Contents online. The link to the file is:
http://www.mastering-mentalray.com/mental_ray/TOC.pdf
Jenni
Faster Renders in mental ray
A user on the mental images forums posed a question about tips for speeding up renderings, and reduce the yellow tint when using incandescent light presets. The first tip is to buy my book, of course. ;)
However I can summarize a few things:
You can adjust the yellow of the render with the Whitepoint setting in the mr Photographic Exposure control. For incandescent lighting use something between 2800 and 3300 Kelvin to make the yellowish light appear white. The default Whitepoint of 6500K is an outdoor daylight setting. Alternately you can set the color temperature of the lights to the D65 reference color and leave the mr Photographic exposure control at the default. For the Blackbody shader just set the color temp to 6500. See Chapter 2 “Light, Shadow, and Exposure” for more information.
Combining FG and GI is usually the best and fastest indirect illumination solution. You can use a lower FG setting with GI than when using FG alone, in my experience, and since FG Diffuse Bounces are not calculated when using GI the FG pass is very fast. GI can cause its own problems with light leakage, though, but every scene is different. See Chapters 5 and 6, “Indirect Illumination and Final Gather” and “Global Illumination and Caustics”.
For render setting, the Image Precision sliders in the Rendered Frame Window do not also adjust the Spatial Contrast setting. You may get better images and faster render times by using Samples Per Pixel of Min/Max 1 and 16 and reducing the RGB value of Spatial Contrast to .02, perhaps. This will force additional sample subdivision and the use of the Max setting more often. Some scenes may need 1 and 64, some 1/4 and 4, but experimentation on your particular scene is important. See Chapters 1 and 4, “Essentials” and “Rendering” for more information on these settings.
For lights, setting the Far Attenuation value to the maximum effective distance for that light can greatly increase rendering speed. For instance if the light’s intensity at 15 meters is minimal, then set the Far Attenuation to Start of 15m and End of 20m. For many scenes this is the the most significant improvement is speed you can make. Rendering your scene with just that one light (w/o Attenuation) can give you an idea if its area of influence with your current exposure settings. See Chapter 2 “Light, Shadow, and Exposure” for more information.
Materials can also be a great source of rendertime woes. Ambient Occlusion forces multiple rays to be shot for every visible sample of a surface to determine the occlusion, and this can take a long time. Use AO where it makes an impact, and only when you have the time.
Another material issue is reflection levels; simply changing a ProMaterials Wall Paint (or Autodesk Wall Paint) from Flat to Satin turns it into a reflective surface and can greatly increase render time. In ProMaterials and Arch & Design change the reflections level to 1 if you need simple reflectivity; most of the time you don’t need or want more than 1. For Autodesk materials you do not have a setting per-material, however you can try reducing the overall reflection level in the Render Frame Window.
Jenni
3ds Max 2011 Announced
If you have not seen the news yet, 3ds Max 2011 has been announced by Autodesk. See Ken P’s blog at: http://area.autodesk.com/blogs/ken/3ds_max_2011_announced The software was also demonstrated at the Game Developer’s Conference (GDC) on March 11th through 13th. There are a lot of new features in Max, but also a lot of new stuff for Maya and Softimage 2011. Those videos will be available soon on www.area.autodesk.com
I can’t discuss anything beyond what has been released so far, and as I understand it 3ds Max Design 2011 will be announced at a later date. Being involved with the alpha, beta and release candidate (RC) versions of the software is an interesting process. It is fun, of course, to hear about the new details being introduced into the software, and it is also interesting to hear some of the reasons things are the way they are. Suffice it to say that I think the developers are fighting the good fight to get you the reliable tools you need to get the job done, and to get the resources to get the development accomplished. It isn’t always what a particular user might like, but the world is full of compromises. There is never infinite resources for the things we want to see accomplished. I think with this release people will see things start to come together, and the Excalibur information Autodesk released helped to explain the path they are taking.
I like to see them bring in tools from other developers, and the new Slate Material Editor (SME) is a welcome addition. Based on the Node Joe editor, it is one tool that saw a lot of internal development from Autodesk; it wasn’t a simple drop-in. Since it was continually changing during the writing of the book, Chapter 2, “Materials and Maps”, was a bit of a moving target and saw a lot of revisions in the many months I worked on the book. The final release of Max has a couple subtle differences, and I’ll see if anyone notices. :)
My opinion of the SME is that it will greatly help people at all levels create and manage materials. It will particularly help new users that are typically confused by the way that you navigate materials and maps in legacy Max; the user adds a bitmap to a material and the UI switches to the bitmap settings, and they don’t know how to get back to the parent level or where they are and why their settings disappeared. Hopefully they will eventually find the Material/Map Navigator button, or the Up To Parent button, but I have dealt with a lot of new users that have a very hard time getting their head around the editor. With the SME everything is visible and you see the connections between maps and materials. Much better, IMHO, and a targeted response by Autodesk in improving workflow. The Excalibur information promises more node-based workflow in Max, so the next few years will be exciting times in the Max world.
Another feature that has been announced is the Quicksilver rendering engine. This is a GPU-based renderer and a pretty cool tool. Do not expect it to run well on old and/or low-end graphics cards. A newer card with 1gb of memory (or more) is likely to give you the features and speed that you are expecting from the renderer. It isn’t mental ray, but for many scenes and on the right hardware it can burn through images pretty quickly.
The new functionality of Containers is another welcome addition. I have been slow to warm up to containers, I’ve had a few issues, however the new ability to make local ‘reference-like’ edits to the objects may sway me into using these more often. The XRef Scene functionality is what I typically use when importing and sharing external geometry.
Ken mentions “Viewport Display of 3ds Max Materials”. Each new release of Max has brought additional functionality to the viewport Hardware Shading functionality, and this is an area of serious development at Autodesk, as is the Quicksilver renderer. The better your video card the better it works, and a nice game-rated card gives an excellent preview of your rendering in the viewwport.
3ds Max Composite, based on the Toxik application, is another welcome addition. In Chapter 10 “mr for Design” I cover a few basics for compositing an image, however Composite is a big application and spending some quality time with the introduction tutorials, and going over the training DVDs from Ken LaRue’s company www.thestreetproductions.com will give you a firm foundation for effectively using this program. I still use Combustion but as I move from PNG and RPF files to OpenEXR using Composite will be essential. The only drawback to Composite is that it shares a license with Max and only runs on the same workstation as Max; you can’t run it on a separate workstation from Max.
Ken P’s 3ds Max 2011 announcement makes mention of “mental ray 2011″, which is mental ray 3.8. I understand that Ken mentioned on CGTalk that iray is not going to be included with Max 2011 or any mr3.8 Autodesk applications, and I believe that it really comes down to keeping only production-ready tools in the program. The iray application was still in development when the 2011 features were set in stone an completing the current toolset was the focus. I hope that it will come out as a subscription benefit down the line, but Autodesk does not tell the beta testers about their future plans and I have no inside information.
One very cool addition to Max 2011 is the ability to control mental ray via string options. For instance, in MAXScript, you can perform a few options to access mental ray and then send a character string such as:
“importons” on
…to enable that feature. I will most assuredly have more on using mental ray strings here on the web site, and I’m working on a few things now to help optimize your mental ray settings.
As far as Importons and Irradiance Particles, Max Tarpini will be coming out with a new plugin that is compatible with Max 2011. Although Max 2011 is plugin compatible with plugins for Max 2010, mental ray has changed and so must Max T’s plugin. The Max 2011 ctrl.ghost plugin shipping with the book worked in earlier betas but broke at some point. You can access my information on the ctrl.ghost plugins at:
I’ll be adding an article on the updated ctrl.ghost and mental ray functionality once 3ds Max/Design is released.
Jenni
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