Turn off or reduce shadow texture size in flight during heavy clouds



A few years ago, I made a video about how to improve performance in P3D during sunrise/sunset and heavy cloud coverage by reducing the cloud shadow texture size in the P3D configuration file.

Recently, I had a flight in P3D v4 where I encountered heavy overcast conditions, and looking into the sun during dusk made my FPS drop to 20's, while under normal circumstances, it was in the 40's. I made no changes to the texture size (which in P3Dv4 is called "TRANSLUCENT_SHADOW_TEXTURE_SIZE", and the default value is 512). Turning off cloud shadows completely or lowering the texture size to 128 boosted my FPS to 60, so cloud shadows (and their texture size) still have a massive impact on the FPS during sunset conditions.

In this regard, I was wondering if it would be possible to have a future version of Active Sky (or another software) change the shadow texture size in flight, or to temporarily turn off cloud shadows altogether. If you fly an airliner during sunset above overcast conditions, you don't see the ground shadows casted by clouds anyway, so reducing the texture size from, let's say 512 to 128, would have no visible effect. However, on my tests, it greatly improves FPS even during most extreme cloud conditions.

Some may say, why not setting the shadow texture size to 128 in the cfg file from the beginning? While it reduces the load during the above described conditions, it looks jaggy during daytime when the cloud coverage is not overcast. Therefore, I wish the program would be able to temporarily reduce the cloud texture size only during heavy overcast conditions (in which jagginess wouldn't be noticeable anyway), but change the value to 512 during daytime and/or less-than-overcast cloud cover, so that the cloud shadows wouldn't be jaggy. It is of course possible to turn off cloud shadows in the graphics settings, but you can't alter the texture size (and for switching off shadows, it would be more convenient to have AS automatically do it).

Is this possible from a technical standpoint? Could Active Sky access P3D's shadow settings during flight? An implementation of this feature would help improve performance and keep up the immersion.
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Hello again,

I know that the AS team is busy working on the upcoming new product for P3Dv4 and v5, but can I ask you if the suggestion is or will be considered for the new product or its future update? I think it would tackle quite an important problem...


Staff member
We're reviewing this but have no answers/commitment/schedule for this at this time. Not sure it is possible but we can see the potential value. Thanks for the feedback.