Convert matrix_float4x4 to x y z space

user_594898 0
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I'm using ARKit and trying to get the position of the camera as a rotation and (x,y,z) coordinates in real world space. All I can manage to get is a matrix_float4x4, which I don't really understand, and euler angles only show the rotation.

Here's what I currently have:

let transform =  sceneView.session.currentFrame?.camera.transform
let eulerAngles =  sceneView.session.currentFrame?.camera.eulerAngles

Here's the output I'm getting:

eulerAngles: float3(-0.694798, -0.0866041, -1.68845)

transform: __C.simd_float4x4(columns: (float4(-0.171935, -0.762872, 0.623269, 0.0), float4(0.982865, -0.0901692, 0.160767, 0.0), float4(-0.0664447, 0.640231, 0.765304, 0.0), float4(0.0, 0.0, 0.0, 1.0)))

Is there a way to convert the matrix_4x4, or is there an easier way to get this information?

Thanks!

swift3 arkit
3 Answers

Two ways you can get the position of the camera:

  1. By using the currentFrame property of session you can get the transform of the camera and then use that to get the position:

    matrix_float4x4 cameraTransform = self.sceneView.session.currentFrame.camera.transform;
SCNVector3 cameraPosition = SCNVector3Make(cameraTransform.columns[3].x, 
cameraTransform.columns[3].y, cameraTransform.columns[3].z);

  2. Or get the position of the camera using the pointOfView property of the sceneView:

    SCNVector3 cameraPosition = self.sceneView.pointOfView.worldPosition;
user_39752070
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