Over at Sundog Software, we have released version 1.086 of
SilverLining, our SDK for real-time cloud
and sky rendering for DirectX9 and OpenGL C++ Windows developers.
This latest version improves performance, memory footprint, and visual
quality, enabling large cumulus cloud decks that stretch from horizon to
horizon. Single-product royalty-free licenses are available for $250
USD. Full source code is provided with the purchase of a license. A free
evaluation version of the SDK, documentation, and an interactive demo
app are available at
Cumulus, stratus, and cirrus clouds are simulated. We model the
transmission of light from the sun and the moon through the atmosphere,
and then simulate multiple forward scattering of the light through the
clouds. The clouds themselves are procedurally generated; they are
“grown” at initialization time using a cellular automata. For faster
startup times, cloud decks may be saved and restored once created.
To ensure fast rendering, we employ vertex shaders and vertex buffer
objects to draw the many billboards that make up each cloud within the
GPU. This allows us to draw each cloud as a single triangle strip that’s
stored locally on the video card. Distant clouds may optionally be
rendered as dynamically generated imposters to reduce geometry and depth
An ephemeris model simulates the positions of the sun, moon, stars, and
planets for any given location at any given time, and this feeds into
the lighting simulation. We apply a tone-mapping operator to the
simulated light to provide realistic perceptual lighting in both daytime
and nighttime scenes, and we expose this lighting information to the
application for lighting your scene.
The SDK integrates seamlessly with any OpenGL or DirectX application
under Windows. It has been successfully integrated with several
third-party rendering engines; you just need to initialize the library,
call it at the beginning of your frame (where we draw the sky), call it
at the end of your frame (where we draw the clouds), and you’re done.
Since SilverLining saves and restores all transforms and rendering
states surrounding its rendering, it coexists with any other renderer.
Developers who desire tighter integration may develop their own renderer
plug-ins to call directly to their own engines, in addition to our
OpenGL and DirectX9 plugins.
Please log in or register to post a reply.
whow, nice volumetric clouds! do the clouds also have a shadow on the