I know Right? that would be a major blow.

Edited August 10, 20205 yr by UAL4life

18 hours ago, Ianrivaldosmith said:

I personally hope I never have to tweak again. 

🤣😂  That made me smile

15 hours ago, LHookins said:

I have.  Been a couple of years.  Wish I'd taken more photos.

Hook

hahaha.  

12 hours ago, GSalden said:

You are correct : the clouds certainly look low resolution.

Just like the TrueSky clouds in P3Dv5, even at a high resolution.

Yes, They are low resolution.  I believe Clouds are a huge hit on frame rate. Maybe (maybe), this is why they made them low-res. I believe they will increase the resolution a bit by August 18th-  but not much.  Third-party devs like REX will then come in and make them as Hi-res as we wish; but, we need to be ready to "pay the fps tax."

9 minutes ago, joemiller said:

Yes, They are low resolution.  I believe Clouds are a huge hit on frame rate. Maybe (maybe), this is why they made them low-res. I believe they will increase the resolution a bit by August 18th-  but not much.  Third-party devs like REX will then come in and make them as Hi-res as we wish; but, we need to be ready to "pay the fps tax."

The resolution in MSFS I do not know, but in P3Dv5 TrueSky they look low resolution even at the highest setting ( 2048 ).

As I use 2x 4K 43” as one wide frontview I see every less sharp object very clear...

 

The clouds are not rendered using any conventional texture based rendering technique.

They use a pretty cutting edge (as far as games go) technique called raymarching. The clouds are an actual 3 dimensional volume, and then rays are shot away from the camera at predefined intervals (i.e. the rays march away from the camera). At each interval, a test is performed to detect if the ray has intersected a volume. If it has, then each successive intersection along the ray reports its depth in the volume. This information colors the pixels via a lighting equation: i.e. if the ray is very deep, then the color will tend to be darker as more light is absorbed in the direction of the viewer. A 3d noise equation modulates the "surface" of the volume so that clouds aren't just haze boxes.

For the lighting side, rays are also cast from the sun, and then marched towards the ground (again at predefined intervals). If the rays hit a volume, then a light scattering equation comes up with the correct amount of light to add to the previous color pixel. This also naturally allows for cloud ground shadowing and self shadowing, as the light rays also calculate how much light is lost along the way to color the resultant pixels all over the scene. This is also what leads to god-rays: holes in the cloud cover where the rays passed through unabaded are still full strength and may then intersect with haze or cloud volumes below, and scatter light to the camera.

This can produce sharp edged volumes, but tends not to, because necessarily a limited number of marching steps can be performed before the performance impact is too large. The number of steps can be thought of as analogous to a 3d resolution, or for more 3d savvy folks, a voxel, in a sense. As you crank up the number of steps, or 3d resolution, you can produce greater detail, but the perf tends to decrease as an exponential function (square law). So, there's a balance.

A couple of games have used this technique so far (Horizon Zero Dawn is the one that comes to mind immediately), but it isn't super common. It's a hell of a shader to write and optimize and knowing what goes into it I'd say the results are something you'd normally see in a rendering whitepaper a couple of years before you see a game with it. Very, very cool stuff.

Guerilla did a presentation at SIGGRAPH 2015 about how they landed on using raymarching for clouds, and some of the performance challenges they ran into: http://advances.realtimerendering.com/s2015/The Real-time Volumetric Cloudscapes of Horizon - Zero Dawn - ARTR.pdf. Even for folks with casual interest or technical knowledge it is a great read.

-Matt