使用手势在ARSCNView中移动SCNNode

Question

我一直在尝试使用UIPanGestureRecognizer移动附加到iOS ARKit中的UISceneView的SCNNode。它在x方向上可以很好地移动，但是我似乎无法弄清楚如何在y方向上移动它。我采用了两种不同的方法，每种方法都没有成功：

1. How do I find my mouse point in a scene using SceneKit?

2. https://github.com/rajubd49/ARKit-Sample-ObjC

对于为什么y维度似乎与x行为不同的任何见解，将不胜感激。这可能与仅在XZ平面上的运动有关吗？这是上面＃2中引用的GitHub示例代码之后的代码：

=============== >>

//移动SCNNode-（void）handlePanGesture：（UIPanGestureRecognizer *）pagr{

switch (pagr.state)
{
    case UIGestureRecognizerStateBegan:
    {
        CGPoint tapPoint    =   [pagr locationInView:sceneView];
        NSLog(@"%s tapPoint  %@",__FUNCTION__,NSStringFromCGPoint(tapPoint));

        NSArray *hitResults = [sceneView hitTest:tapPoint types:ARHitTestResultTypeFeaturePoint | ARHitTestResultTypeEstimatedHorizontalPlane];
        lastHitTestResult   =   [hitResults firstObject];
    }
        break;
    case UIGestureRecognizerStateChanged:
    {
        CGPoint tapPoint            =   [pagr locationInView:sceneView];
        if (windScreenView.buttonState == GypsyTargetAdded)
        {
            NSArray *hitResults         =   [sceneView hitTest:tapPoint types:ARHitTestResultTypeFeaturePoint | ARHitTestResultTypeEstimatedHorizontalPlane];
            ARHitTestResult *result     =   [hitResults lastObject];

            [SCNTransaction begin];

            SCNMatrix4 lastMatrix   =   SCNMatrix4FromMat4(lastHitTestResult.worldTransform);
            SCNVector3 lastVector   =   SCNVector3Make(lastMatrix.m41, lastMatrix.m42, lastMatrix.m43);

            SCNMatrix4 newMatrix    =   SCNMatrix4FromMat4(result.worldTransform);
            SCNVector3 newVector        =   SCNVector3Make(newMatrix.m41, newMatrix.m42, newMatrix.m43);
            CGFloat dx              =   newVector.x-lastVector.x;
            CGFloat dy              =   newVector.y-lastVector.y;
            SCNVector3 adjVector        =   SCNVector3Make(gypsyTargetNode.position.x + dx, gypsyTargetNode.position.y + dy, gypsyTargetNode.position.z);
            gypsyTargetNode.position    =   adjVector;

            [SCNTransaction commit];

            NSLog(@"%s lastVector: x = %f, y = %f, z = %f",__FUNCTION__,lastVector.x,lastVector.y,lastVector.z);
            NSLog(@"%s newVector: x = %f, y = %f, z = %f",__FUNCTION__,newVector.x,newVector.y,newVector.z);
            NSLog(@"%s dx = %f, dy = %f",__FUNCTION__,dx,dy);
            NSLog(@"%s gypsyTargetNode.position: x = %f, y = %f, z = %f",__FUNCTION__,gypsyTargetNode.position.x,gypsyTargetNode.position.y,gypsyTargetNode.position.z);
            NSLog(@"%s hitResults.count: %li",__FUNCTION__,hitResults.count);
            lastHitTestResult       =   result;
        }
    }
        break;
    case UIGestureRecognizerStateEnded:
    {
        lastHitTestResult   =   nil;
    }
        break;
    default:
        break;
}
}

这是输出控制台的片段。请注意，计算出的“ dx”始终为.000000。

[CalibrationController handlePanGesture:] tapPoint  {207.33332824707031, 507}

[CalibrationController handlePanGesture:] lastVector: x = -0.016018, y = -0.083625, z = 0.006696

[CalibrationController handlePanGesture:] newVector: x = -0.015562, y = -0.083862, z = 0.006658

[CalibrationController handlePanGesture:] dx = 0.000456, dy = **-0.000237**

[CalibrationController handlePanGesture:] gypsyTargetNode.position: x = -0.018142, y = -0.087894, z = 0.008041

[CalibrationController handlePanGesture:] hitResults.count: 2

[CalibrationController handlePanGesture:] lastVector: x = -0.015562, y = -0.083862, z = 0.006658

[CalibrationController handlePanGesture:] newVector: x = -0.015562, y = -0.083862, z = 0.006658

[CalibrationController handlePanGesture:] dx = 0.000000, dy = **0.000000**

[CalibrationController handlePanGesture:] gypsyTargetNode.position: x = -0.018142, y = -0.087894, z = 0.008041

[CalibrationController handlePanGesture:] hitResults.count: 2

[CalibrationController handlePanGesture:] lastVector: x = -0.015562, y = -0.083862, z = 0.006658

[CalibrationController handlePanGesture:] newVector: x = -0.015150, y = -0.083862, z = 0.006565

[CalibrationController handlePanGesture:] dx = 0.000412, dy = **0.000000**

[CalibrationController handlePanGesture:] gypsyTargetNode.position: x = -0.017730, y = -0.087894, z = 0.008041

[CalibrationController handlePanGesture:] hitResults.count: 2

[CalibrationController handlePanGesture:] lastVector: x = -0.015150, y = -0.083862, z = 0.006565

[CalibrationController handlePanGesture:] newVector: x = -0.014686, y = -0.083862, z = 0.006361

[CalibrationController handlePanGesture:] dx = 0.000463, dy = **0.000000**
    

我一直在尝试使用UIPanGestureRecognizer移动附加到iOS ARKit中的UISceneView的SCNNode。它在x方向上可以很好地移动，但是我似乎无法弄清楚如何在y上移动它。

Answer 1

对于平移手势，请执行以下方法：