Patent ID: 7023438

Claim:
A method for generating a shadow map, the method comprising: receiving information associated with a first light source; generating at least a first ray and a second ray from the first light source; determining a first ray transmittance function associated with the first ray; determining a second ray transmittance function associated with the second ray; processing information associated with the first ray transmittance function and the second ray transmittance function; determining a first visibility function based on at least information associated with the first ray transmittance function and the second ray transmittance function; wherein the determining a first ray transmittance function includes: processing information associated with the first ray; determining at least a first surface transmittance function based on at least information associated with the first ray; determining at least a first volume transmittance function based on at least information associated with the first ray; processing information associated with the first surface transmittance function and the first volume transmittance function; determining the first ray transmittance function based on at least information associated with the first surface transmittance function and the first volume transmittance function.