Common light parameters FCOLLADA extension

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Extension information
  • Purpose: unstated
  • Company(s): [[Feeling Software]]
  • Product(s): [[FCollada]]
  • Last updated: unstated
  • Contact for technical issues:
This article is part of the COLLADA extensions directory
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Common Light Parameters

This <extra> at the <light> level includes common light parameters supported directly by the FCollada library and used within ColladaMax, ColladaMaya and/or the Feeling Viewer. Each standard type of light has its own additional common light parameters.

Light type Elements Supported
<ambient> <intensity>
<point> <intensity>
<directional> <aspect_ratio>, <constant_attenuation>, <falloff_angle>, <falloff_exponent>, <intensity>, <linear_attenuation>, <quadratic_attenuation>, <target_default_dist>, <outer_cone>, <overshoot>
<spot> <aspect_ratio>, <dropoff>, <intensity>, <outer_cone>, <penumbra_angle>, <target_default_dist>


Element Attributes supported Description
<aspect_ratio> sid Contains one floating point value: the aspect-ratio of the ellipsoidal or rectangular form of a spot light or a restricted directional light. This element's contents can be animated using the 'sid' attribute.

Moved to the MAX3D profile in 3.04.

<constant_attenuation> sid See the element of the same name in the COLLADA specification. This can be used with restricted directional lights.
<falloff_angle> sid See the element of the same name in the COLLADA specification. Contains one floating point value: the absolute inner angle of the spot light or restricted directional light. This can be used with restricted directional lights.
<falloff_exponent> sid See the element of the same name in the COLLADA specification. This can be used with restricted directional lights.
<intensity> sid Contains one floating point value: a multiplicative factor for the light's color. This element's contents can be animated using the 'sid' attribute.
<linear_attenuation> sid See the element of the same name in the COLLADA specification. This can be used with restricted directional lights.
<quadratic_attenuation> sid See the element of the same name in the COLLADA specification. This can be used with restricted directional lights.
<target_default_dist> sid Contains one floating point value: the default distance of the expected light target for non-targeted lights. For targeted lights, this element should not be present. This element's contents can be animated using the 'sid' attribute.

Moved to the MAX3D profile in 3.04.

<outer_cone> sid Contains one floating point value: the absolute outer angle of the spot light or restricted directional light. This element's contents can be animated using the 'sid' attribute.
<overshoot> Contains one boolean value: whether the directional light is restricted. Overshooting directional lights are the OpenGL standard. Restricted directional lights give a positional, ellipsoidal beam of light.

Moved to the MAX3D profile in 3.04.

<penumbra_angle> sid Contains one floating point value: the angle of the penumbra relative to the fall-off angle. This element's contents can be animated using the 'sid' attribute.

Deprecated in 3.05. This value has been replaced by a smarter calculation involving the <outer_cone> angle to improve interoperability between ColladaMax and ColladaMaya.

Examples

 <light id="ambient_light">
   <technique_common>
     <ambient>
       <color>1 1 1</color>
     </ambient>
   </technique_common>
   <extra>
     <technique profile="FCOLLADA">
        <intensity sid="intensity">1.0</intensity>
     </technique>
   </extra>
 </light>
 <light id="point_light">
   <technique_common>
     <spot>
       <color>1 1 1</color>
       <constant_attenuation>1</constant_attenuation>
       <linear_attenuation>0</linear_attenuation>
       <quadratic_attenuation>0</quadratic_attenuation>
     </spot>
   </technique_common>
   <extra>
     <technique profile="FCOLLADA">
       <intensity>1</intensity>
     </technique>
   </extra>
 </light>
 <light id="directional_light">
   <technique_common>
     <directional>
       <color>1 1 1</color>
     </directional>
   </technique_common>
   <extra>
     <technique profile="FCOLLADA">
       <constant_attenuation>1</constant_attenuation>
       <linear_attenuation>0</linear_attenuation>
       <quadratic_attenuation>0</quadratic_attenuation>
       <falloff_angle>30</falloff_angle>
       <falloff_exponent>0</falloff_exponent>
       <intensity>1</intensity>
       <outer_cone>35/outer_cone>
       <aspect_ratio>1</aspect_ratio>
       <overshoot>0</overshoot>
       <target_default_dist>240</target_default_dist>
     </technique>
   </extra>
 </light>
 <light id="spot_light">
   <technique_common>
     <spot>
       <color>1 1 1</color>
       <constant_attenuation>1</constant_attenuation>
       <linear_attenuation>0</linear_attenuation>
       <quadratic_attenuation>0</quadratic_attenuation>
       <falloff_angle>40</falloff_angle>
       <falloff_exponent>1</falloff_exponent>
     </spot>
   </technique_common>
   <extra>
     <technique profile="FCOLLADA">
       <intensity>1</intensity>
       <outer_cone>45</outer_cone>
       <aspect_ratio>1</aspect_ratio>
       <dropoff>0</dropoff>
       <penumbra_angle>5</penumbra_angle>
       <target_default_dist>240</target_default_dist>
     </technique>
   </extra>
 </light>