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COLLADA Import and Export

Page status (reviewing guidelines) Partial page Proposed fixes: none

WIP REASON: WIP documentation, feature still in development, check here

Mesh

Import

Supported geometry types are

• tris
• polylist
• polygons
  • ngons are triangulated automatically
• trifans

Export

Mesh data is exported as <polylist>.

Light

Import

Blender does a best effort on importing lights from a .dae. If a Blender profile is detected for lights, all values from these will be used instead. This ensures 100% reimport from a Blender exported .dae. <extra> support has been added in Blender 2.57.

Export

A Blender profile for lights has been added through the <extra> tag. The entire Lamp struct from Blender will be exported through this profile, with the exception of Light curve falloff .

Material & Effect

Since Blender 2.57 some changes to export of effects have been made. Most notably <lambert> is exported if and only if specularity is 0.

Animation

• Support for Object(Mesh, Camera, Light) transform Animations. Only euler rotations, which is the default option for Objects, can be exported for now. For armature bone animations euler and quaternion rotation types are supported.
• Import and export of animations for the following parameters are supported:-
  • Light
  • Camera
  • Material Effects
• Non Skin controlling armature bone animation.
• Animations of Armatures with skin deforming bones.
• Animations of Armatures in Object mode.
• Fully rigified Armature animations. For export of rigified Armature animations
  • Select Bake Action. ( press space in 3d view and Type Bake Action )
  • If you have only the deform bones selected check "only selected". This will give smaller dae. Otherwise uncheck "Only Selected".
  • Check "Clear Constraints".
  • Bake Action.
  • Select the mesh and the deform bones. Then export to COLLADA while checking only selected option. ( Selecting only the Mesh and bones is not strictly necessary. Selecting and export only selected will give smaller dae.)
  • Demonstration

Nodes

On import parent transformations for <instance_node>s is properly propagated to child node instances. Blender materials are exported with the following mapping:

• phong
• blinn
• lambert

For bone nodes which are leaf nodes in the armature tree, or if a bone has more than one children a blender profile for tip with an <extra> tag, is added for those joint nodes. To correctly derive the bone->tail location on re-import.

Important things to remember

• object and datablock names are constrained to 21 characters (bytes).
• uv layer names are constrained to 32 characters (bytes).
• only armature animation on mesh, single skin controller
• no support for modifiers yet

When importing a .dae that has <instance_node>s on exporting this information is essentially lost and these nodes will be <node>s.