Format of Environment Data Files

The default extension for the name of an environment file is .dat.

[environment file] =

[header] { [rest environment] } <end>

The type in [header] of the file must be scene.

[rest environment] =

[outdoor] | [indoor]

[indoor] =

<indoor> <NUMBER> $int$:16 [indoor entity list]

[outdoor] =

<NUMBER> $int$:16 [outdoor entity list]

The value for <NUMBER> specifying the number of entities in the file is only informative. The entities are read until the end-of-file is reached.

[indoor entity list] =

[indoor entity list item] | [indoor entity list]

[indoor entity list item] =

[exterior] | [interior] | [info]

[outdoor entity list] =

[outdoor entity list item] | [outdoor entity list]

[outdoor entity list item] =

[flattop] | [tree] | [trunk] | [trunktree] | [ground] | [info]

There is at most one [ground] object allowed.

The following entities are allowed within an outdoor scenario

[interior] =

<interior> { "name" } <{> <NUMBER> $int$:16 [corner list] [height] [material index] <}>

[exterior] =

<exterior> { "name" } <{> <NUMBER> $int$:16 [corner list] [height] [material index] <}>

Note that the height of the indoor environment is automatically taken as the largest height of the objects in the file.

[flattop] =

<flattop> { "name" } <{> <NUMBER> $int$:16 [corner list] [height] { [ground height] } [material index] <}>

[corner list] =

[corner list item] | [corner list]

[corner list item] =

[point] { ( <nodiff> | <diff> $float$:32 ) } { <stealth> }

The [corner list] must have as many items as the value of <NUMBER> indicates. Marking a corner with <nodiff> means that the corner is not considered for diffraction, marking it with <diff> and a height value means that a diffraction points must lie at least at that height. Marking a corner with <stealth> means that the wall from this corner to the next corner in the list is not considered for reflections.

[ground] =

<ground> <{> ( [height field] | [mesh] ) [material index] <}>

[mesh] =

<mesh> <POINT> <NUMBER> $int$:16 [point list] <TRIANGLE> <NUMBER> $int$:16 [index list]

The number of items in the [index list] must be equal to three times the value of the <TRIANGLE> <NUMBER>. An index must not exceed the number of points. Counting starts at zero.

[point list] =

[point list item] | [point list]

[point list item] =

[point] [height]

[index list] =

[index list item] | [index list]

[index list item] =

$int$:16

[tree] =

<tree> <{> [point] [radius] [height] { [ground height] } [material index] <}>

[trunk] =

<trunk> <{> [point] [radius] [height] { [ground height] } [material index] <}>

[trunktree] =

<trunktree> <{> [point] [radius] [height] [radius] { [ground height] } [material index] <}>

[info] =

<info> <{> <NUMBER> $int$:16 [points] <}>

The [points] list must have as many items as the value of <NUMBER> indicates.