Making Blurry Texture Crisp in 3ds Max

It is common to get blurry bitmap texture in renders, especially if the geometry is almost perpendicular to the camera line of sight (i.e. at glancing angle). Here is a render for illustration. Observe how the lines between tiles are blurred.

While reading the book "Architectural Rendering with 3ds Max and V-Ray", I learned about the filtering option "Summed Area" for Bitmap map under "Bitmap Parameters" rollout. Here is where the option is in Material Editor:

By default, the filtering method is "Pyramidal."
If you are wondering what image filtering is about, you can read the Wikipedia article on Mipmap. Basically a texture image needs to be filtered so that the rendered texture is anti-aliased.
Here is a comparison between the 2 methods.

Observe that the white lines between tiles are now crisp and nice.

... Too nice, in my opinion, that I wondered if there was a further story to this option.
According to Autodesk, both methods take approximately the same render time, but "Summed Area" method needs much more memory:

• "Pyramidal" needs around 133% of the size of the bitmap;
• "Summed Area" needs around 400% of the size of the bitmap.

This means that "Summed Area" method should be used sparingly. My own take at the moment is to use this for Diffuse maps of geometries, especially those at glancing angles to the camera such as ground, floor, et cetera. Perhaps Bump maps need "Summed Area" filtering depending on geometry and lighting. Specular maps should not need it.

Mental Ray used to not support "Summed Area" method, as was discussed in this CGTalk forum thread. However, I tested this and found that Mental Ray in 3ds Max 2011 supports "Summed Area" method.

Finally, there is an alternative method described by Neil Blevins.

I admit that the title of this post is rather bombastic. Apologies.

Mazda RX-8 Compositing

Mazda RX-8 compositing

The VFX class I am teaching is currently in the topic of Lighting, Rendering, & Compositing. One student, Suresh Kalai, suggested using a new car model for the class exercise. It is a Mazda RX-8 2004. Here is the starting render.

Initial render using materials that come with the model

I spent half a day fiddling with the new model (a messy business because all geometries are separate), working on the shaders, lighting, and rendering. Here is a work-in-progress render.

WIP render after half a day

As always, the 80/20 Rule happens. I spent the next 2 class days fiddling with the materials (while the students are working on their files) until I am happy with the final product above.

Mazda RX-8 model courtesy of archibase.net.
Back plate and HDRI sky courtesy of HDRI-Hub.com.

Bruce Willis Roundtable

I have to admit this post is a bit of embarrassment. This roundtable video is a continuation of my past work I posted here in my personal blog.


Bruce Willis Bust from Denny Iskandar on Vimeo.

I needed "only" 2 years to finish rendering this roundtable. However, while working on this roundtable, I found that I did learn a few things since then:

• I put the camera too close to the subject, causing big perspective distortion on the face.
• The (relatively) bright background interfered with the lighting.
• The Sub-Surface Scattering shader setting that I used was rather harsh.

I thought I made the roundtable better with respect to these factors. What do you think?

Reflection on Batman Tumbler - Part 3: Checking Angles

This is the final part of a material walkthrough for Batman Tumbler model. I explained the problem in Part 1 as well as offered a partial solution. Part 2 followed up with map manipulations to improve the render.

At the end of Part 2, I got this render.

Figure 1. Render at the end of Part 2.

It looks pretty good: the metal parts have reflection and dirt details at the front part can be seen. Now it is time to check renders of other frames.

The roundtable animation has 120 frames. At this stage, I do not want to render every frame yet. Instead, I rendered every 30 frame to get four different angles of the Tumbler.

Figure 2. The rendered four angles

Looking at the 2 back angles, I found the back wheels looked too "painted" due to the Diffuse map. To reduce the painted feel, I composited Noise maps on top of the Diffuse bitmap. As figure 3 shows, I used 2 Noise maps to break the regular look of the Noise maps.

Figure 3. Composite map to reduce the painted feel of wheel diffuse

For consistency, I made the same modification to the front wheel Diffuse map. Here are the final renders. (On hindsight, the front wheels look too new in these renders.)

Figure 4. Four angles of the final render

I turned on Final Gather to make the shadow areas brighter when rendering the final video. I made further minor parameter tweaks that made the final video look slightly different from the renders above.
Here are two points about Arch & Design that I learned from this test:

• Setting Reflection Glossiness very low will result in dark or even black reflections.
• Reflection Color should be close to white.

I hope you find this walkthrough useful.

Credit: The Tumbler model and textures were created by Henry Chan.