在 SceneKit 中的平面上重复纹理

Question

我有一个 32x32 .png 图像，我想在 SCNPlane 上重复。我得到的代码（见下文）导致图像被拉伸以适应飞机的大小，而不是重复。

代码：

let planeGeo = SCNPlane(width: 15, height: 15)

let imageMaterial = SCNMaterial()
imageMaterial.diffuse.contents = UIImage(named: "art.scnassets/grid.png")

planeGeo.firstMaterial = imageMaterial

let plane = SCNNode(geometry: planeGeo)

plane.geometry?.firstMaterial?.diffuse.wrapS = SCNWrapMode.repeat
plane.geometry?.firstMaterial?.diffuse.wrapT = SCNWrapMode.repeat

Answer 1

我修好了。图像似乎被放大了。如果我这样做 imageMaterial.diffuse.contentsTransform = SCNMatrix4MakeScale(32, 32, 0)，图像会重复。

Answer 2

我在 ARKit 中实现平面可视化时遇到了同样的问题。我想将检测到的平面可视化为棋盘图案。我通过创建自定义 SCNNode called a "PlaneNode" with a correctly configured SCNMaterial 来修复它。 material 使用 wrapS, wrapT = .repeat 并根据平面本身的大小正确计算比例。

看起来像这样：

看看下面的代码，内联注释包含解释。

class PlaneNode : SCNNode {

    init(planeAnchor: ARPlaneAnchor) {
        super.init()
        // Create the 3D plane geometry with the dimensions reported
        // by ARKit in the ARPlaneAnchor instance
        let planeGeometry = SCNPlane(width:CGFloat(planeAnchor.extent.x), height:CGFloat(planeAnchor.extent.z))
        // Instead of just visualizing the grid as a gray plane, we will render
        // it in some Tron style colours.
        let material = SCNMaterial()
        material.diffuse.contents = PaintCode.imageOfViewARPlane
        //the scale gives the number of times the image is repeated
        //ARKit givest the width and height in meters, in this case we want to repeat
        //the pattern each 2cm = 0.02m so we divide the width/height to find the number of patterns
        //we then round this so that we always have a clean repeat and not a truncated one
        let scaleX = (Float(planeGeometry.width)  / 0.02).rounded()
        let scaleY = (Float(planeGeometry.height) / 0.02).rounded()
        //we then apply the scaling
        material.diffuse.contentsTransform = SCNMatrix4MakeScale(scaleX, scaleY, 0)
        //set repeat mode in both direction otherwise the patern is stretched!
        material.diffuse.wrapS = .repeat
        material.diffuse.wrapT = .repeat
        //apply material
        planeGeometry.materials = [material];
        //make a node for it
        self.geometry = planeGeometry
        // Move the plane to the position reported by ARKit
        position.x = planeAnchor.center.x
        position.y = 0
        position.z = planeAnchor.center.z
        // Planes in SceneKit are vertical by default so we need to rotate
        // 90 degrees to match planes in ARKit
        transform =  SCNMatrix4MakeRotation(-Float.pi / 2.0, 1.0, 0.0, 0.0);
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    func update(planeAnchor: ARPlaneAnchor) {
        guard let planeGeometry = geometry as? SCNPlane else {
            fatalError("update(planeAnchor: ARPlaneAnchor) called on node that has no SCNPlane geometry")
        }
        //update the size
        planeGeometry.width = CGFloat(planeAnchor.extent.x)
        planeGeometry.height = CGFloat(planeAnchor.extent.z)
        //and material properties
        let scaleX = (Float(planeGeometry.width)  / 0.02).rounded()
        let scaleY = (Float(planeGeometry.height) / 0.02).rounded()
        planeGeometry.firstMaterial?.diffuse.contentsTransform = SCNMatrix4MakeScale(scaleX, scaleY, 0)
        // Move the plane to the position reported by ARKit
        position.x = planeAnchor.center.x
        position.y = 0
        position.z = planeAnchor.center.z

    }
}

Answer 3

你可以从Scene kit viewer学习它假设你的场景kit中有SCNplane

创建场景文件拖一个平面

12英寸的尺寸是0.3048

和select漫反射图像

现在你的图像有 4 个网格，如图所示

我们希望每个盒子都以每英寸显示，所以对于 12 英寸，我们需要 12 盒子 * 12 盒子，因为我们有 12 英寸盒子

计算一下。首先我们需要将 0.3048 米转换为英寸

即米/0.0254答案是12.

但我们需要每个网格显示在每一英寸中，所以我们还需要除以 12 / 4 = 3

现在转到显示 material 检查器并将比例值更改为 3

12寸飞机可以看到12个盒子

希望对您有所帮助

Answer 4

要在 SceneKit 编辑器中执行此操作，请在场景中 select 您的飞机（如果需要，添加一架），然后 select 右上角的 "Material Inspector" 选项卡。然后，在 "Properties" 和 "Diffuse" 下，select 你的纹理。现在，通过单击 "Diffuse" 左侧的克拉展开漫反射部分，然后向下移动到显示 "Scale" 的位置。在这里，您可以增加缩放比例，使纹理看起来重复而不是拉伸。对于这个问题，OP 必须将缩放比例设置为 32x32。

在 SceneKit 中的平面上重复纹理

Repeating a texture over a plane in SceneKit

xcode

textures

repeat

swift