Describe 3D AOI =============== Now that the [scene pose is estimated](aruco_marker_description.md) considering the ArUco markers description, [areas of interest (AOI)](../../argaze.md/#argaze.AreaOfInterest.AOIFeatures.AreaOfInterest) need to be described into the same 3D referential. In the example scene, the two screens—the control panel and the window—are considered to be areas of interest. ![3D AOI description](../../img/aoi_3d_description.png) All AOI need to be described from the same origin as markers on a [right-handed 3D axis](https://robotacademy.net.au/lesson/right-handed-3d-coordinate-frame/), where: * +X is pointing to the right, * +Y is pointing to the top, * +Z is pointing backward. !!! warning All AOI spatial values must be given in **centimeters**. ### Edit OBJ file description OBJ file format could be exported from most 3D editors. ``` obj o Left_Screen v 0.000000 -0.000000 -0.000000 v 15.000000 -0.000000 -0.000000 v 0.000000 18.963333 -6.355470 v 15.000000 18.963333 -6.355470 f 1 2 4 3 o Right_Screen v 20.000000 0.000000 -0.000000 v 35.000000 0.000000 -0.000000 v 20.000000 18.963337 -6.355472 v 35.000000 18.963337 -6.355472 f 5 6 8 7 o Control_Panel v 49.500000 30.000000 18.333333 v 55.500000 30.000000 18.333333 v 49.500000 38.000000 18.333333 v 55.500000 38.000000 18.333333 f 9 10 12 11 o Window v -57.800000 5.500000 -33.500000 v 46.000000 15.500000 -35.000000 v 1.500000 53.000000 -1.000000 v 50.200000 61.000000 6.000000 v -35.850000 35.000000 -15.000000 f 13 14 16 15 17 ``` Here are some common OBJ file features needed to describe AOI: * Object line (starting with the *o* key) indicates AOI name. * Vertice line (starting with the *v* key) indicates AOI vertices. * Face line (starting with the *f* key) links vertices together. ### Edit JSON file description The JSON file format allows for the description of AOI vertices. ``` json { "Left_Screen": [[0, 0, 0], [15, 0, 0], [0, 18.963333, -6.355470], [15, 18.963333, -6.355470]], "Right_Screen": [[20, 0, 0], [35, 0, 0], [20, 18.963337, -6.355472], [35, 18.963337, -6.355472]], "Control_Panel": [[49.5, 30, 18.333333], [55.5, 30, 18.333333], [49.5, 38, 18.333333], [55.5, 38, 18.333333]], "Window": [[-57.8, 5.5, -33.5], [46, 15.5, -35], [1.5, 53, -1], [50.2, 61, 6], [-35.85, 35, -15]] } ```