SketchUp - Quick Start

Following is a tutorial that will help you get started using the plugin. Before doing so, though, it is a good idea to make sure that you have read the plugin overview.

Getting Started

First, it is worth mentioning that it is entirely possible to render a scene simply by clicking the Render button (or opening the Maxwell Fire window and clicking the Fire button). The plugin will automatically convert SketchUp's materials into Maxwell materials, using various heuristics to decide how each material ought to be converted. This process, however, is somewhat limited by a lack of information in the source SketchUp material; for example, all non-transparent materials will be exported as simple diffuse Maxwell materials, simply because there is no parameter in the SketchUp material by which the plugin could infer whether or not it should be exported differently.

The determination of whether to export as transparent is made based both on the SketchUp material's Opacity value and on its color; in cases where it seems appropriate, the plugin will generate what is known in Maxwell as an AGS material -- this is a glass-like material which works with non-volumetric meshes and also renders faster than a real dielectric glass material, due to its lack of refraction.

That aside, it is quite simple to customize how SketchUp materials are translated by the plugin. By default, the plugin's representation of the material (as seen in its material editor) will infer color and texture from the SketchUp material it is associated with. Additionally, a Roughness parameter is given; as this is reduced, the material will become shinier and plasticine.

Scene & Material Setup

Let's try this out to see how it works. I have imported this nice model of a bike from the 3D Warehouse (Yamaha R1 lap mod from Nicolez); it is imported as a Component. Then I created a copy:

Open

Using Fire

The model already comes with some SketchUp materials assigned. Click the Fire button on the toolbar:

Open

The Fire window will open, the materials exported to Maxwell and the rendering will automatically begin:

The model has been rendered but there’s no ground. Let’s activate it in the next step.

The Scene Manager

In the plugin's toolbar, click the Scene Manager button:

The plugin's Scene Manager window will be shown. It is the single central point of access to all Maxwell-related scene parameters. As you will see, there are five tabs at the top of the window; select the third tab to show the Environment options.

Scroll down to the Ground Plane section and change the Mode option from Disabled to Application.

Using this mode, the plugin will read the ground plane options from SketchUp and generate a suitable approximation in the exported Maxwell scene. If we launch Fire again we’ll get this:

Now we can see the ground, but the materials look a bit dull as they have all been automatically translated as diffuse materials with the color or texture from the SketchUp materials. Let’s spice them up.

Scene Manager - Material tab

In the Scene Manager, change to the first tab to show the Materials options.

Using the Material Picker Tool from the toolbar you can point to part of the model to select its material and it will show in the Materials tab.

or using this button from the top row of the Materials tab

You can also select the material from SketchUp’s Materials tray or choosing the material from the dropdown menu at the top bar of the Materials tab.

I have picked the red material of the front part of the bodywork and clicked the Refresh Preview button (at the bottom-right of the preview image) to generate a material preview for this material:

As you can see, by default, materials use a Character type of Automatic and a Roughness value of 97.0; this produces a diffuse material. We can adjust the Roughness value down to 10% to see what that looks like. The preview will refresh automatically after adjusting the Roughness. If you inspect the Type drop-down, you will see that there are several types of materials available that you can try, each with its own properties. I will go with the Car Paint type, but here are some of them.

As you can see, the plugin translates the SketchUp materials and lets you tune its character to give them more advanced properties.

You can also assign the active material to any selected object by using the Assign to Selected Entities button:

If the SketchUp material is using a texture, it will be used in the Maxwell material as main texture and, optionally, as bump map. Also, if the texture includes transparency, it will be used to cut through the material in most of the characters.

Camera Setup

Before we render the scene, let's set up the camera; select the second tab in the Scene Manager to show the Maxwell camera parameters for the current SketchUp scene (in this case, there is no scene, so the camera will simply be named Current).

By default, cameras use what is referred to in the plugin as Viewport mode; when this is the case, the plugin will always infer the camera's resolution settings from the SketchUp viewport. We will continue to use this mode, but before we render, let's set the camera's focal distance; click the Set Focal Distance button in the plugin toolbar.

The plugin will prompt you to select a point in the scene; I will pick a point in the nearest part of the front wheel of the bike.

Rendering the Scene

Let's render the scene now and see how it looks like (I have quickly tuned some of the main materials applied to the bike by assigning some characters. You can choose to render in the fast interactive window (Fire) or in Maxwell Render, which gives more options but is not interactive in the sense of changing the point of view.

Using Maxwell Render

Click Render in the plugin's toolbar:

The scene will be exported to an MXS file, and Maxwell Render will be started, rendering the exported file:

Altering the Scene

In the Environment tab you can switch the Environment Type from Physical Sky to Constant Dome if you prefer a more neutral light and also turn off the sun if you wish. If you activated Multilight in the Scene Manager > Output tab > Engine section, you can turn off the sun after the render has finished or change the intensity of the illumination.

I’ll change the resolution of the camera to get quicker results for these tests by going to the camera tab and changing the Mode from Viewport to Custom and adjusting the X and Y parameters:

Since the size of the scene does not produce any noticeable DOF (depth of field) in the camera, I’ll move the camera closer to the near bike, open up the fStop to 1.2 in the Camera > Optics section, and set the focal distance again, using a point similar to the one which was chosen previously. This produces a more dramatic composition as in the first image below. Naturally, setting the focal distance to a point on the far bike would result in an image like in the second image:

Note that even though we have altered the camera's fStop, the overall exposure of the image has not changed appreciably; this is due to the Maxwell camera's Lock Exposure to EV (Exposure Value) feature.

Image Based Environment

To wrap up, let's render using an Image-based environment.

Go to the Environment tab and select Image Based from the Type drop-down. Now, browse to an HDR image in the Background channel; I will use the Dosch dh207.hdr file (this is included in a Maxwell Render Suite installation). Let's also disable the sun, so either turn off Shadows in SketchUp, or click the Sun toggle button at the Sky section of the Scene Manager's Environment page. While we're here, let's set up a custom color for our ground plane; set Ground Plane > Mode to Custom Color and set the color to RGB [50, 50, 50].

Since there will now be less light in the scene, we will also need to adjust the camera's exposure, so switch to the Scene Manager's Camera tab and adjust EV down to 8.0. Rendering now produces an image similar to this: