Hi,

I would like to report another viewport interaction issue on macOS in Houdini 22.

When a light is selected, Houdini normally allows the light to be positioned directly from the viewport using the **Diffuse** and **Specular** placement modes.

On my Macs, these functions do not work.

### Steps to reproduce

1. Create and select a light.
2. Activate the viewport light placement tool.
3. Choose **Diffuse**.
4. Click anywhere on an object or surface in the viewport.
5. Repeat the same test using **Specular**.

### Actual result

Nothing happens.

I can click anywhere in the viewport with the light selected, but the light position does not change.

The same happens with both:

* **Diffuse**
* **Specular**

However, the other mouse shortcuts of the same light placement tool work correctly:

* **Ctrl + Left Mouse Button** correctly changes the light distance.
* **Ctrl + Shift + Left Mouse Button** correctly changes the light intensity.

So the light placement state itself appears to be active, but clicking in the viewport to position the light using the Diffuse or Specular modes has no effect.

I have tested this on two different Apple Silicon Macs and the problem is identical on both systems:

**Mac mini**

* Apple Silicon
* macOS Tahoe 26.6.2 (25G83)

**Mac Studio**

* Apple Silicon
* macOS Tahoe 26.6.2 (25G83)

Tested with:

* Houdini 22.0.368
* Houdini 22.0.407

The issue is present in both Houdini versions and on both machines.

I have also encountered a similar viewport interaction problem with the camera focal point controls on macOS, which I previously reported. In this case, the problem specifically affects the **Diffuse and Specular viewport light placement controls**.

Thank you.

Are you able to change intensity in the viewport? Placement and intensity is broken for me on Windows 11.

RESOLVED

In Houdini 22.0.426, both the camera focus point issue and the light positioning issue have been fixed.
Thank you, SideFX, for your continued support.

Massimo Baita