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pointAt Usage member(whichCastmember).model(whichModel).pointAt\ (vectorPosition{, vectorUp}) member(whichCastmember).camera(whichCamera).pointAt\ (vectorPosition{, vectorUp}) member(whichCastmember).light(whichLight).pointAt\ (vectorPosition{, vectorUp}) member(whichCastmember).group(whichGroup).pointAt\ (vectorPosition{, vectorUp}) Description 3D command; rotates the referenced object so that its forward direction vector points at a specified world relative position, then it rotates the referenced object to point it’s up direction vector in the direction hinted at by a specified relative vector. The object’s front and up direction vectors are defined by the object’s pointAtOrientation property. 458 Chapter 12: Methods Parameters vectorPosition Required. Specifies the world relative position. This value can also be a node reference. vectorUp Optional. Specfies a world relative vector that hints at where the object’s up vector should point. If this parameter isn’t specified, then pointAt defaults to using the world’s y axis as the up hinting vector. If you attempt to point the object at a position such that the object’s forward vector is parallel to the world’s y axis, then the world’s x axis is used as the up hinting vector. The direction at which you wish to point the object’s forward direction and the direction specified by vectorUp do not need to be perpendicular to each other being as this command only uses the vectorUp parameter as a hinting vector. Example This example points three objects at the model named Mars: the camera named MarsCam, the light named BrightSpot, and the model named BigGun: thisWorldPosn = member(“Scene”).model(“Mars”).worldPosition member("Scene").camera("MarsCam").pointAt(thisWorldPosn) member("Scene").light("BrightSpot").pointAt(thisWorldPosn) member("Scene").model("BigGun").pointAt(thisWorldPosn, \ vector(0,0,45)) If you use non-uniform scaling and a custom pointAtOrientation on the same node, e.g., a model, using pointAt will likely cause unexpected non-uniform scaling. This is due to the order in which the non-uniform scaling and the rotation to properly orient the node are applied. To workaround this issue, do one of the following: • Avoid using non-uniform scaling and non-default pointAtOrientation together on the same node. • Remove your scale prior to using pointAt, and then reapply it afterwards. For example: scale = node.transform.scale node.scale = vector( 1, 1, 1 ) node.pointAt(vector(0, 0, 0)) -- non-default pointAtOrientation node.transform.scale = scale |