Open5

RenderMan Interface Bytestream 規格の確認をする

yokamakyokamak

AreaLightの設定。
Windows 32bit Renderer.
xrt renderer2.5.0の examples/arealight/illum2_1bounce.ribを参考にする。
サンプル1

area.rib
AttributeBegin
  Surface "constant"
  Attribute "light" "nsamples" [16]
  AreaLightSource "arealight" 1 "intensity" 4.000000 "string shadowname" "raytrace"
  Polygon "P" [ 0.950000 2.400000 -0.950000 0.950000 2.400000 -1.550000 1.550000 2.400000 -1.550000 1.550000 2.400000 -0.950000]
AttributeEnd
Illuminate 1 1
yokamakyokamak

AreaLightの設定。
サンプル2
intensityは、1200。

area2.rib
#area_patch
AttributeBegin
#Attribute "visibility" "int transmission" [1]
  Surface "constant"
  Attribute "light" "nsamples" [64]
AreaLightSource "arealight" 1 "intensity" 1200 "string shadowname" "raytrace"
PointsPolygons
	[ 4 ][ 0 1 3 2 ]
	"P" [-20 15 -20 20 15 -20 -20 15 20 20 15 20]
AttributeEnd
Illuminate 1 1
yokamakyokamak

AreaLightのポリゴン面の向きは、+YupでOK。
Metasequoiaメタセコイアモデラーを使って、「面の生成」で数値入力確認。