April 30, 2014

Texturing, Lighting & Rendering 'The Church Of Light' in 3ds Max

by 


In this tutorial, Pratik Gulati walks us through how he created his stunning image, 'The Church of Light', using 3Ds Max. He covering all of the modeling, material creation, lighting, render passes and the post-production techniques used.


A Brief History

The Church of the Light is a small structure on the corner of two streets in the town of Ibaraki, in Osaka, Japan. The architect, Tadao Ando, is famed for using Zen philosophies when conceptualizing his structures, and one theme he expresses in this work is the dual nature of existence. The space within the chapel is defined by the strong contrast between light and solid. In the chapel, light enters from behind the altar through a cross cut in the concrete wall, and it's at this intersection of light and solid, that the occupant is meant to become aware of the deep division between the spiritual and the secular within themselves.

Modeling

As you can see in the image below, the geometry itself is actually very simple - walls on all four sides and 1 major window at the back-right through which light enters. All of the furniture models in the scene were created using simple box-modeling techniques, and once modelled, I used instancing to create multiple copies throughout the church.

Step 1

To model the bench, first create a plane in the front view.

Step 2

After converting it to an editable poly, select the lower edge and shift drag it downwards to extrude it as shown.

Step 3

Select these two edges and connect them with 3 divisions. With that done, tweak the vertex positions as shown in the final image below.

Step 4

Repeat the above process to complete the two horizontal sections shown.

Step 5

Here we can use the bridge tool to easily connect up these two pairs of edges.

Step 6

With the main shape created, apply a shell modifier to add thickness to the object. We want the different sections to end up roughly square - the settings that I used are shown below.

Step 7

As we should do with all photorealistic models, we now need to chamfer all of the corner edges to give our model a beveled look. My chamfer settings are shown but the important thing is to ensure that it looks right to you!

Step 8

After duplicating this object twice, I also created the back support and the seat itself using exactly the same techniques described above. Our bench is now done!

Step 9

To model the podium, first create a box and convert it to an editable poly.

Step 10

Select 3 of the side faces and inset them as shown.

Step 11

With that done, delete the forth side polygon.

Step 12

Now select the inset faces and extrude them in slightly.

Step 13

Now, just as on the chair, we need to go in and chamfer all of our edges.

Step 14

To finish the object, add a cube on top of the model, a cross on the front and a cube on each side, making sure to chamfer the edges. The other objects in the scene were all constructed using a similar polygonal modeling method.

Rendering an Ambient Occlusion Pass

I added in an Ambient occlusion pass using Mental Ray to add more depth and weight to the final render. I personally prefer Mental Ray for this as it's fast and, in my opinion, gives a better result than the Vray dirt shader.

Step 1

First change the current renderer from scan line to Mental Ray.

Step 2

Then add in a new Mental Ray material.

Step 3

Under surface, assign Ambient/Reflective Occlusion.

Step 4

Increase the Samples to 500 - the more samples you add, the less grainy the final render will appear. Also increase the Spread and Max Distance as shown.

Step 5

Final Gather and GI should not be turned on while rendering an ambient occlusion pass, so just increase the sampling quality and enable raytracing as shown. You can now render out your AO pass.

Lighting & Render Settings

As you can see there are 5 Vray lights (1-5) for the interior illumination and 1 directional light (6) which acts as the sun in the final scene.

Step 1

First of all, add the 6 lights shown above in to your own scene. The image below shows the different settings I have used for the 6 lights. The more advanced parameters are as follows :
  • Invisible - this setting controls whether the VRayLight source itself is visible in the final render.
  • Subdivs - this setting defines the quality of the light. A value of 8-10 should be used for test renders, whilst 15-20 should be used for the final image. Increasing the number of samples increases your overall render time.

Step 2

Now assign a simple Vray material to all of the objects in the scene. We do this to ensure quick render times during the testing process. Then, in the Common tab of theRender Setup dialog, set the image resolution and the file destination output.

Step 3

Moving onto the Vray tab itself, first disable Default Lights, and then set the image sampler type to Adaptive DMC, turn on the Antialiasing filter and set the type toCatmull-Rom. Finally, change the color mapping type to Exponential. This mode will saturate the colors based on their brightness, which can be useful to prevent burn-outs around light sources in the scene, whilst maintaining the overall tone of the image.

Step 4

in the Indirect illumination tab, select Irradiance map and Light cache as the primary and secondary bounce engines. Using an Irradiance map computes indirect illumination at only a few within the scene, and Vray then interpolate the rest of the lighting information from that data. As it only looks at a subset of the total information, the Irrandiance map method is very fast compared to direct computation, especially for scenes with large flat areas.
Now select the High custom preset, and change the HSph. subdivs to 90, and theInterp. samples to 70. The Hemispheric subdivs (HSph. subdivs) value controls the quality of the individual GI samples taken by Vray. Smaller values makes things faster, but may produce an overly blotchy result. Higher values produce smoother images at the cost of increased render time.

Step 5

Under the Light Cache settings, set the Subdivs to 1500, the Sample size to 0.02 andNumber of Passes to 8. Ensure that Store direct light and Show calc. phase are both turned on.

Step 6

Our render settings are now complete so let's move on to the materials.

Materials

There are 3 main materials in the scene; glass, chrome and wood. Let's take a look at their parameters.

Step 1

The glass settings :

Step 2

The chrome settings :

Step 3

The wood settings :

Step 4

After creating and assigning the materials shown above, and hitting render, you should get an image that similar to that shown below. We now need to move into post processing, so save out the render and open Photoshop.

Post Processing

Step 1

Open both the beauty pass (the main render) and the ambient occlusion pass in Photoshop. With the ambient occlusion image active, select all (Ctrl-A) and then copy (Ctrl-C) the contents. Switch to the beauty pass and paste (Ctrl-P) the ambient occlusion pass into a new layer on top of the stack, as shown below. Then switch the ambient occlusion pass to Multiply mode.

Step 2

Now merge the two layers by selecting them both, right-clicking either layer and choosing Merge Layers.

Step 3

We're now going to alter the Brightness and Constrast of our newly merged layer, so with the layer selected go to Image > Adjustment > Brightness/Contrast. Play with the settings until you're happy with the result - my values are shown below - and then clickOK.

Step 4

To add a slight blue tint to the render, go to Image > Adjustment > Photo Filter... In the dialog box, select Cooling Filter (LBB) from the dropdown and set the density to about 10%. Click OK once you're happy with the result.
Advertisement

Step 5

The final step is to add a slight lens flare to our image, so go to Filter > Render >Lens Flare. The first thing we need to do is select the flare center, by clicking right in the centre of the cross in the preview window. With that done, set Brightness to around 70%, and set the Lens Type to 105mm Prime. With that done, click OK to finish.

Step 6

All that's left to do now is save our final image.
Voila! The image is complete. Happy rendering!

0 comments:

Post a Comment