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V2 :: BEHIND THE SCENES
Presented by Next Limit QA Dept.
in cooperation with Maxwell Render A-Team
September, 2009


____Preface_______________________________________________________________________________

Dear Friends,

During the development of Version2, we've made a lot of tests and achievements.
While coding/testing, we were also always watching the forum for your requests.
Now, as we're proud releasing Version2 with its ultimate power, we decided to
share further technical facts behind the scenes with you; our dedicated users.
We're sorry for the long post but, it's very hard to squeeze months of work
inside a single post. But, we're already sure you will enjoy reading it all.
Maybe it's not full of eyecandy images but the things you've waited for long.

Thank you for your priceless support!

In math we trust,

Next Limit Team





____Index_________________________________________________________________________________

1) CORE IMPROVEMENTS DONE
1. Color Accuracy Improved
2. Surface Fidelity Improved
3. Rough Transmissives Improved
4. Illumination Strategy Improved
5. IBL Illumination Improved
6. Caustics Improved
7. Bump / Normal Mapping Improved
8. Tonemapping Improved

2) CORE LIMITATIONS AVOIDED
1. Reflectance Limitations Avoided
2. Reflectance / Transmittance Normalization Avoided
3. High Poly Emitter Moiré Artifacts Avoided
4. Sun Limitations Avoided
5. AGS Limitations Avoided

3) CORE BUGS FIXED
1. Shading of Non-Proportionally Scaled Objects Fixed
2. Low Poly Smooth-Shading Artifact Fixed
3. Emitter Inside Rough Transmissives Fixed
4. Dozens of Minor Bugs in Other Areas Fixed

4) NEW FEATURES ADDED
1. Layer Stacking Added
2. Texture Alpha as Input Added
3. Color Multilight Added
4. Conductor Fresnel (Nd+K) Added
5. Global Bump / Normal Mapping Added
6. Thin SSS Added
7. IES and EULUMDAT Support Added
8. New Wizards Added
9. Output Color Spaces Added
10. Multiple Bit Depth Output Added
11. Separate Buffers for Render Channels Added
12. Material Override Added
13. Realflow Support Added
14. New Networking Added
15. Scripting System Added
16. Numerous Other Features Added

5) HIDDEN FEATURES
1. ...Find at the bottom of this post...




____CORE IMPROVEMENTS DONE______________________________________________________________

1.1 Color Accuracy Improved (Spectral <> RGB Conversion)
Due to conversion between RGB and Spectral space we were losing valuable amount of information in vivid/pure colors. This is over.
The overlaid chips are the reflectance colors given by the user. On the left, 1.7.1 is capable of getting close to the desired color.
Now, Version2 ensures higher accuracy between input and output colors, as seen on the right.



Here's the improvement in action:



another one...





1.2 Surface Fidelity Improved (BSDF, Roughness Model)
BSDF is completely renewed and optimized for faster and more accurate results. The overall response to light is vastly improved.
It's one of the main factors bringing us less noise in same render time. Processing of multiple BSDF is also highly optimized for saving more time.
Overall result boosted the performance of indirect illumination and more depth added to the scene.

The improvement coming with new BSDF + Color Accuracy is not something small. Compare the peak realism in indirectly lit areas.


Model courtesy of Jotero

Roughness continuity and darkening on the edges are not problems anymore. Now, with new roughness model the transition to lambertian is seamless.
You can imagine how much this was affecting the overall quality in glossy (Roughness 1-99) surfaces we're using everyday.
This scene has spheres on a circular path with increasing roughness under skydome. On the left, it's 1.x and on the right it's Version2.
The spheres are now free from shading issues and they look perfectly invisible as you may also predict. Notice the natural grey of skydome is a gift of spectral accuracy.



See the darkening edge on this metal sphere in 1.7.1 (on the left) and with Version2 improvement on the right.



Now, we're proud to present one of the key point which leads v2 to absolute success in surface fidelity and realism.
In the below scenes, you will see a white sphere and walls under white skydome.

First two movies on a row is the comparison of range between Roughness 0 and Lambertian.
Please click and drag the mouse on the movies to investigate the continuity in roughness in each version.
You will notice Version2 does not have a jump and has a seamless transition to Lambertian in opposite to 1.7.1

Continuity in Roughness


Below is a comparison of Roughness 99 under skydome. You can see 1.7.1's shading limitation is darkening in the frontal angles and
bright in the grazing angles like a velvet surface. So, it was clear Version2 must overcome this limitation and it was not easy but done.
On the right, see how new BSDF and Roughness responds to light uniformly in Version2.

Improved Uniform Shading


Now, let's see the improvement in action:





1.3 Rough Transmissives Improved (BTDF, TIR, Roughness)
As BSDF consists BRDF and BTDF together, the above improvements had a quite big impact on rough transmissive objects, namely frosted glass.
With the adaptation of this improvement, the beauty of rough caustics and TIR tested its limits. It's hard to express the difference in words, here are the images:




Courtesy of roch_fr



other examples of Version2 rough glass...







1.4 Illumination Strategy Improved (Emitter Optimization)
Previous optimizations used to put the priority on relatively powerful emitters so, the parts illuminated by the weaker ones had to converge slower.
Today, further optimizations gave Version2 the chance to handle these situations nicely without leaving them in dark.

.



1.5 IBL Illumination Improved (Superior HDRI Environments)
This is surely one of the best improvement in Version2. In 1.7.1, it was truly impossible having sharp shadows especially from small bright
parts of HDR Images (especially from the sun). Now, Version2 can handle an illumination off from a single pixel precisely and efficiently.

Version2 is far beyond in same time...



Shadows from sun were impossible until now...



Lit with a small white point oh a blank HDR...


Courtesy of Mike Verta

in 30 secs...



after 3 minutes in both...



HDR Image for above examples:



The following comparison is lit with a single white pixel on a blank HDR. 1.7.1 (on the left) couldn't even start to converge the result...





1.6 Caustics Improved
We're happy to say, Version2 has a revolutionary improvement in this area. Caustics off from directional lights, far emitters, small emitters and sun
are now thousands of times faster than any previous version up to date. It's so good that you can promptly spot it just in SL2.

After 30 seconds...


In 2 minutes...


...enjoy without noise





1.7 Bump / Normal Mapping Improved
As you know, Bump / Normal Mapping is a shading method making the surfaces look like they have more geometric detail than they really have.
With all the technical conflicts in its nature, it was not very possible to make unbiased bumps properly using high values.
Version2 has a remarkable leap in quality also in this area.









1.8 Tonemapping Improved
Dark areas were under risk of banding. Improved low dynamic range conversions now allows silk smooth transitions in Version2.


Courtesy of tresdk




____CORE LIMITATIONS AVOIDED______________________________________________________________

2.1 Reflectance Limitations Avoided
In Version2, maximum upper reflectance is not limited anymore. Previously the upper limit was Grey 242.
This means now you can make surfaces reflecting 100% of the light back by setting RGB 255, 255, 255
With this improvement, the infinite mirror test lasts forever and further optimizations in this area now avoids
late converging of non-early bounces.

1.7.1


Version2




2.2 Reflectance / Transmittance Normalization Avoided
High reflectance and transmittance values were not doing good together. For this reason, the core was normalizing
user values prior to rendering when their sum is exceeding the limits. Version2 now allows all peak values without restrictions.
This also means, the chromatic range of reflectance and transmittance is now wider than before.





2.3 High Poly Emitter Moiré Artifacts Avoided
Emitters with high poly count were causing a kind of Moiré pattern which is even faintly persisting in higher SL and
it was essential using emitters made of few polygons. It's still true we suggest low poly emitters for speed but
with the help of this improvement, they are not adding these kinds of patterns anymore.

1.7.1


Version2




2.4 Sun Limitations Avoided
Very large scene boundaries were an issue in 1.7 with sunlight, for example a plane several km in size.
Version2 handles these situations perfectly...





2.5 AGS Limitations Avoided
AGS solution was single sided and it had a limitation of not being able to show the backfaces of itself. This was a problem with overlapping panels.
In Version2, new AGS model using layer opacity is a double-sided solution and it's free from this limitation.

Compare below images to find how Version2 handles new AGS...



Here's a complicated AGS example in action:







____CORE BUGS FIXED__________________________________________________________________

3.1 Shading of Non-Proportionally Scaled Objects Fixed
Shading of non-proportionally scaled objects were under risk of being shaded incorrectly depending on behavior of host application.
Version2 has no more shading problems with these objects.







3.2 Low Poly Smooth Shading Artifact Fixed
Smoothing of low polygon geometry has always been a problem in unbiased renderers. Version2 improved the situation by minimizing the
incorrect shading of triangles. It's always highly suggested to create meshes at the required density but now, even the low poly ones will look better.





3.3 Emitter Inside Rough Transmissives Fixed
Emitters in rough glass had geometry dependant darkening issues. With the help of massive improvements in BTDF and
the roughness model, this problem does not exist in Version2 anymore.


Courtesy of m-Que



3.4 Dozens of Minor Bugs in Other Areas Fixed
Other than a few fixes mentioned above, Version2 had countless bug-fixes mainly in the core and the rest. As you may agree,
it was just impossible to list them all here. But, if there's something working so smooth which was failing before, that's the only reason.





____NEW FEATURES ADDED______________________________________________________________

4.1 Layer Stacking Added
Long time waited multilayer stacking is here! We don't accept any limits in creation of complicated materials anymore.
Fully flexible and easy to use material stacking system is added in Version2. No more pain with making decals, dust, dirt and more.
Control layers holding multiple BSDFs with layer opacity/masks and create the final look in one go.







4.2 Texture Alpha as Input Added
You can now use the alpha channel of a texture directly in the Material Editor.





4.3 Color Multilight Added
We can't find words to describe it. You already know what it means very well...
Render once and chance colors/intensities of emitters in real-time! Only possible with Version2.



Click and drag the mouse on the movie to see the brandnew Mutlilight in action.



4.4 Conductor Fresnel (Nd+K) Added
We added a second parameter (K) for allowing users to specify a more
accurate reflection falloff for conductors (metals). There is an important
difference in the fresnel curve between dielectrics (glass) and conductors,
which makes Nd not enough for creating more accurate metals.
This parameter, together with the improvements in BSDF roughness model
allows you to create more accurate metal surfaces and avoid black edges.

Nd+K values for different metals can be found on the internet (for ex. http://www.luxpop.com,
make sure you search for Nd+K values at a wavelength of 589nm)
The new metal wizard sets these too parameters for you for the type of metal you choose.





4.5 Global Bump/Normal mapping added
In the material properties, you will find a new Global Bump/Normal mapping parameter
that affects all the components in all the Layers in the stack.





4.6 Thin SSS added
This was one of the most anticipated feature and it was impossible not to include in Version2.
Tents, sheets, lampshades, leaves and more... Comes with Thickness Mapping!















4.7 IES and EULUMDAT support Added
Version2 can now use IES/EULUMDAT files based on measured emission data
from luminaire manufactures. The file is applied to a standard emitter material.
In Studio, a preview of the light profile can be seen in the viewport and the material editor
displays a graph of the profile. Several IES files are included with the install, courtesy of Erco.







4.8 New Wizards Added
Wizards are completely renewed and empowered. They all have new parameters for more possibilities.

Carpaint


Velvet


and more...



4.9 Output Color Spaces Added
Now, you're not limited to narrow sRGB gamut as Version2 offers a palette of color spaces to make a pick from.
New color spaces include; sRGB, Adobe 1998, Apple, PAL, SMPTE-C, Wide Gamut, ProPhoto, ECI, Color Match and more...





4.10 Multiple Bit Depth Output Added
You can now choose between 8,16,32 bit output depending on the output
format you choose. For example the .tif format supports all three.
The "Depth" dropdown in Studio also adapts depending on the chosen output
format to show you only the supported bit depth for that format.

If you have chosen the wrong bit depth when starting the render, you can also
specify it after the render is finished in Maxwell, from File>Save Image. Maxwell
will ask you in which bit depth you want to save the image.

Extra tip for Studio: You can drag & drop one of the input folders over the other
to copy/paste the path. For example drag the Image input folder icon over the
MXI input folder icon and the path will be paste there, adding the .mxi suffix.
This works for all folder icons in Studio.





4.11 Separate Buffers for Render Channels Added
The MXI format can now hold multiple buffers which allows, among other things,
to easily preview each selected render channel inside Maxwell by clicking on its corresponding button.
Another huge advantage is that channels are now resumable and also work with Network rendering.





4.12 Material Override Added
This functionality allows you to override all materials (except emitter materials)
in your scene with the default.mxm included in the install, or any other mxm
you choose. It's useful for example if you want to do quick 'clay' renders of your model
to check lighting and geometry.





4.13 RealFlow support added
Maxwell V2 is compatible "out of the box" with RealFlow.
This enables RealFlow users to use Maxwell V2 to generate procedural
geometry and meshes at render time, and also render individual fluid particles.





4.14 New Networking Added
The Maxwell Network is now it's own component instead of networking
being part of Maxwell.exe. The separation of the network node from Maxwell
provides much better error handling and stability.

A new Add Job wizard makes it very easy to add a network render job, and also solve
problems in a cooperative render related to wrong input/output paths. You can add
Coop, Single, Animation and also new in V2 add a batch render job - select several MXS files
and set them up for batch rendering through network.

In addition, many other functionalities have been added, and better logging system
to detect any errors during a network render.





4.15 Scripting System Added
Maxwell Render provides basic scripting capabilities that allow you to make simple scripts
and macros to automate common tasks such as launching render batches, converting
several MXIs at the same time, adjusting lights in several MultiLight MXIs at once etc.
All the parameters of the Maxwell Render UI are accessible through scripts.
The Maxwell Render scripting engine is based on ECMA standards (like other popular scripting
languages such as Javascript and Actionscript), and provides default compatibility with these standards.
The script editor in Maxwell Render also contains a debugger which provides basic
debugging tools common in development environments.

Several sample scripts are included with the install to get you started, page 119 in the manual explains
the scripting system and functions in more detail.





4.16 Numerous Other Features Added
Pixel Interpolation for IBL, Forced Fresnel, SSS w/Trans.Map, Built-in MXM Gallery Access,
Motion Vector Channel, Embedded Alpha and those you will quickly notice once you start enjoying Version2.




____HIDDEN FEATURES__________________________________________________________________

5.1 Vow to Stay a Hundred Percent Unbiased!
Sorry, do not ask for the opposite anymore.

5.2 Our Passion in Developing Maxwell Render
Back to work!