P3D - WORKAROUND PROVIDED Bug with cloud-altitudes, size, and performance issues

[Yoland]

As published in P3D forum by Beau Hollis Rendering System Lead - Prepar3D® Team:
 
We found the issue that is likely causing the majority of cloud related issues in 2.3. Some of the cloud math got tweaked during 2.3 development and the size of clouds got doubled. We do plan on releasing a hot fix but will first prioritize known issues to see what fixes we can get in reasonably soon. In the meantime, you can resolve the cloud issue by doing the following:
Browse to the ShadersHLSL folder. This is in the main application folder where the Prepar3D.exe is. You may need elevated permissions to do this if you installed into program files with standard windows security settings.

• Open Cloud.fx in notepad or another text editor
  Look for this this line (should be around line 300 if you have line numbers enabled in your editor):
  GetScreenQuadPositions( quad, width, height );
  
  Scale the width and height down by half with this change:
  GetScreenQuadPositions( quad, width*0.5, height*0.5 );
  
  Save your changes and close the file

The P3D system should detect the newer file and rebuild the shader, but if it does not, you can clear the shader cache:
Go to DRIVE:\Users\USERNAME\AppData\Local\Lockheed Martin\Prepar3D v2\
Delete the Shaders folder and/or all of its contents. This will clear the cache.

I tested this tweak and it really corrected the very important impact on fps when flying with real weather setting in misty cloudy places... like we find in most cases when flying the Misty Moorings area.

Link to the P3D forum about this subject:
http://www.prepar3d.com/forum-5/?mingleforumaction=viewtopic&t=7984.0

Yoland SPA 348

[Doug]

Yoland is right on with this!  This was the most significant "fix" I've ever seen with P3D.  It completely straightened out my system ... I was having stutters, lower frame rates, and too many clouds!  Now I've been able to kick up the sliders and it is running the best I've ever seen.  I made this change about a week ago and have not had ONE fatal error (and I was having several after flying for a while).  I HIGHLY recommend making this fix ... it will really help you.

Doug

[FSRobert]

I want to chime in and say try the fix. It worked well for me concerning cloud size and overall performance. To be honest I had no idea that something was wrong with the clouds being too large.

In my last video I did not have the fix applied. I am happy with the video and it provided with some surreal dusk flying with the clouds but now with the fix applied the difference is there is a positive way.

Here is a link to the video with the fix NOT applied...maybe you can spot the cloud size being too large.

Video found here ------ >    https://vimeo.com/104812892

[NeptuneP2V7]

Hi Yoland
for this tweak :
Scale the width and height down by half with this change:
GetScreenQuadPositions( quad, width*0.5, height*0.5 );

i change by  GetScreenQuadPositions( quad, width*1, height*0.5 );

and also i try the HDR in this vidéo :

56Csw


X:\Program Files (x86)\Lockheed Martin\Prepar3D v2\ShadersHLSL\PostProcess

line 166 :
     avgLuminance *= 0.85f; by an other float value BLOOM 68 ...

but i back at 0.85f after tests  too bright and falsheeeee light and cloud . May be for futur LM make sliders for adapting to  monitors ...

Happy landing

Patrick