Twinmotion Interior Rendering Guide: Path Tracer and Quality Settings

This guide explains how to approach Path Tracer, reflections, viewport quality, and environment settings when creating interior renders in Twinmotion, based on official documentation. Epic Games’ documentation lists Path Tracer’s hardware requirements and the relevant options in the Preferences and Ambience panels. As the source documentation does not specify a current Twinmotion version number, the steps are limited to the settings shown there.

1. Check your hardware before using Path Tracer

Path Tracer is a progressive rendering mode designed to produce accurate lighting and Global Illumination. According to Epic Games’ requirements, the feature is supported on Windows computers. The graphics card must be from the NVIDIA RTX family or be an AMD RX 6000 series model or newer. NVIDIA T1000 is not supported. The requirements also include at least 8 GB of dedicated VRAM, DirectX 12 support, and up-to-date graphics drivers.

As a first step, run dxdiag in Windows Search to check your DirectX version. To see Twinmotion’s graphics hardware option, go to Edit › Preferences. The Graphic hardware support field on the Settings tab selects DirectX 12 by default on supported GPUs. DirectX 12 is required for Path Tracer and Lumen. If the hardware does not meet these requirements, Twinmotion uses DirectX 11. Epic Games does not recommend changing this setting manually, as doing so may cause instability in the software.

2. Choose sampling presets for your scene

The sampling options in Path Tracer’s Preferences panel define the samples per pixel and light bounces for the quality presets. Open the panel with Ctrl + P, then check the Path Tracer settings on the Settings tab. The figures below are the default preset values stated in the documentation, not recommendations guaranteed to be ideal for every scene.

Rather than using the same preset for every interior scene, consider your presentation needs and working conditions. On systems with multiple NVIDIA graphics cards, the Multi-GPU option can be enabled in the Path Tracer section of Preferences. This feature requires Windows 10 version 2004 or later and an NVIDIA SLI configuration; depending on the generation of the graphics cards, an NVLink or SLI bridge may also be required. According to Epic Games, performance gains can range from 50 percent to 200 percent, depending on the computer configuration and GPUs used. This increase is not guaranteed. Multi-GPU also does not accelerate the Standard or Lumen real-time rendering modes.

3. Evaluate reflections and viewport quality separately

Reflection probes are used in real-time rendering modes to improve interior and exterior reflections, create reflections on glass surfaces, and make mirrors. In the Preferences panel, the default probe resolution for the viewport and exports is 256. The documentation recommends a value of 1024 for creating mirrors. So, treat the higher resolution as an option for scenes that need mirrors, not as a general quality setting for the entire scene.

Viewport image quality is set on the Quality tab in the Preferences panel. The Low, Medium, High, and Ultra levels use 25 percent, 50 percent, 75 percent, and 100 percent of the screen resolution, respectively. These options affect only the viewport quality on your computer screen; they do not change the quality of exported images, videos, panoramas, or sequences. Epic Games states that exported media is prepared at Ultra quality regardless of the preference selected on the Quality tab. Therefore, do not confuse the quality level shown while working with the settings for the final media.

4. Adjust ambient lighting and clouds as needed

To open the Ambience panel, select Properties at the bottom, then choose an image, video, sequence, or panorama in the Media dock, or click Ambience in the Scene panel. The panel contains Env, Camera, Render, and FX tabs. When using Dynamic sky, scene lighting is shaped by the Sun, Sky, Clouds, and Night sky settings. In Realistic mode, celestial body positions depend on the date, time, location, and north offset, making it possible to create sun studies for specific locations and dates.

When choosing a cloud type, consider both the visual requirements and the performance cost. 2D clouds use less memory, but are not as realistic as volumetric clouds. Volumetric clouds are represented in 3D; they offer animation, shadows, and more extensive customization, but increase the performance cost. The documentation notes that blocky artifacts can appear in volumetric clouds when using Path Tracer, and that reducing their density may help mitigate the issue. When Path Tracer is used with AMD graphics cards, volumetric cloud quality may be reduced due to hardware limitations.

Common mistakes

• Assuming the viewport quality level is the same as exported media quality. Quality settings affect only the viewport.

• Failing to check the Windows, DirectX 12, VRAM, and graphics card requirements before using Path Tracer.

• Assuming Multi-GPU will speed up the Standard or Lumen modes. The documentation states that these modes are not accelerated.

• Expecting the same result from volumetric clouds when blocky artifacts appear in Path Tracer, without changing the settings. The documented solution is to reduce cloud density.

These checks help you plan workflows, especially for architectural presentation scenes featuring glass, mirrors, and daylight. For archviz artists, an important distinction is that viewport images are evaluated using different settings from exported media. If you are considering a hardware purchase or a multi-GPU setup, check the official compatibility requirements in advance; use reflection and cloud options only to the extent required by the scene.