Does anybody know how to make some good looking volumetric
clouds like in crysis,... ? I tried something with billboards, but it
looks not really good.
Volumetric Clouds
Search the forums for CCloudSceneNode, you'll find my old cloud code which partly gets around the shape problem by using recursive levels of detail. The shape of the cloud is still a problem though, it could use some better cloud generators. However, if I was to write it again I'd use a different approach...
I'd like to rewrite it using the same kind of algorithm as the clouds in Just Cause, which I was particularly impressed with. Download the demo from Steam and check it out.. The clouds exist on 2 levels of detail - one for the shape of the clouds in the sky, and the other as fog particles which replace the large ones as they fade out (like, as you enter them)
They have two different types at the weather level, a simple murky strata - a flat billboard with a horizontal axis, which can be bunched together to make a sea of low flying ill weather or fog.
The second type is a generic cotton ball of light fluffy cumulus, another billboard but this time with a vertical axis. These are clumped together to form the small fluffy clouds you see on a fine summer's day, but are also stuck on the top of layers of strata to create more complex cloud formations, like storm clouds. The end result is really nice, there are essentially only 3 simple algorithms to create every type of cloud in the game, and the skies are filled with miles and miles of lovely clouds. The only criticism I have is the amount of bloom, which cheapens the overall effect.
Anyway... I could talk about clouds all night, but I'll leave out my ideas about cheap bounding box self shadowing, density and types of weather for now
I'd like to rewrite it using the same kind of algorithm as the clouds in Just Cause, which I was particularly impressed with. Download the demo from Steam and check it out.. The clouds exist on 2 levels of detail - one for the shape of the clouds in the sky, and the other as fog particles which replace the large ones as they fade out (like, as you enter them)
They have two different types at the weather level, a simple murky strata - a flat billboard with a horizontal axis, which can be bunched together to make a sea of low flying ill weather or fog.
The second type is a generic cotton ball of light fluffy cumulus, another billboard but this time with a vertical axis. These are clumped together to form the small fluffy clouds you see on a fine summer's day, but are also stuck on the top of layers of strata to create more complex cloud formations, like storm clouds. The end result is really nice, there are essentially only 3 simple algorithms to create every type of cloud in the game, and the skies are filled with miles and miles of lovely clouds. The only criticism I have is the amount of bloom, which cheapens the overall effect.
Anyway... I could talk about clouds all night, but I'll leave out my ideas about cheap bounding box self shadowing, density and types of weather for now