Question

我是iOS开发的新手，我自己也很难过。我正在尝试使用每个面具有不同颜色的SceneKit渲染立方体。

这是我到目前为止所得到的：

func sceneSetup() {
    // 1
    let scene = SCNScene()

    // 2
    let BoxGeometry = SCNBox(width: 0.9, height: 0.9, length: 0.9, chamferRadius: 0.0)

    BoxGeometry.firstMaterial?.diffuse.contents = UIColor.redColor()
    let cube = SCNNode(geometry: BoxGeometry)
    cube.position = SCNVector3(x: 0, y: 0, z: -1)
    scene.rootNode.addChildNode(cube)

    // 3
    sceneView.scene = scene
    sceneView.autoenablesDefaultLighting = true
    sceneView.allowsCameraControl = true

但我希望每张脸都有不同的颜色。我该怎么做？

Answer 1

该框由六个不同的元素组成（每边一个）。您可能还注意到，几何对象具有第一个材质的一个属性，但也是一个材质数组的属性。

具有多个元素和多个材质的对象将为每个元素选取材质（和换行）的增量。

例如4个元素和1个材料

Element   1  2  3  4
Material  1  1  1  1

或4个元素和2个材料

Element   1  2  3  4
Material  1  2  1  2  // note that they are repeating

例如4个元素和7个材料

Element   1  2  3  4
Material  1  2  3  4  // (5, 6, 7) is unused

对于盒子，这意味着您可以使用六种材料的阵列在盒子的每一侧都有独特的材料。我在the sample code for one of the chapters中有一个关于我的Scene Kit书（在Objective-C中）的例子：

// Each side of the box has its own color
// --------------------------------------
// All have the same diffuse and ambient colors to show the
// effect of the ambient light, even with these materials.

SCNMaterial *greenMaterial              = [SCNMaterial material];
greenMaterial.diffuse.contents          = [NSColor greenColor];
greenMaterial.locksAmbientWithDiffuse   = YES;

SCNMaterial *redMaterial                = [SCNMaterial material];
redMaterial.diffuse.contents            = [NSColor redColor];
redMaterial.locksAmbientWithDiffuse     = YES;

SCNMaterial *blueMaterial               = [SCNMaterial material];
blueMaterial.diffuse.contents           = [NSColor blueColor];
blueMaterial.locksAmbientWithDiffuse    = YES;

SCNMaterial *yellowMaterial             = [SCNMaterial material];
yellowMaterial.diffuse.contents         = [NSColor yellowColor];
yellowMaterial.locksAmbientWithDiffuse  = YES;

SCNMaterial *purpleMaterial             = [SCNMaterial material];
purpleMaterial.diffuse.contents         = [NSColor purpleColor];
purpleMaterial.locksAmbientWithDiffuse  = YES;

SCNMaterial *magentaMaterial            = [SCNMaterial material];
magentaMaterial.diffuse.contents        = [NSColor magentaColor];
magentaMaterial.locksAmbientWithDiffuse = YES;


box.materials =  @[greenMaterial,  redMaterial,    blueMaterial,
                   yellowMaterial, purpleMaterial, magentaMaterial];

Answer 2

这是Swift 4的答案。

    let colors = [UIColor.green, // front
                  UIColor.red, // right
                  UIColor.blue, // back
                  UIColor.yellow, // left
                  UIColor.purple, // top
                  UIColor.gray] // bottom

    let sideMaterials = colors.map { color -> SCNMaterial in
        let material = SCNMaterial()
        material.diffuse.contents = color
        material.locksAmbientWithDiffuse = true
        return material
    }

    materials = sideMaterials

要更改正面材料，只需抓取材料并更改其内容

let frontMaterial = materials[0]
frontMaterial.diffuse.contents = UIColor.white

Answer 3

泰国你的快速帮助。我使用你提出的代码，但无法使用NSColor所以我尝试了uicolor但我得到的只是一个黑色的立方体，所以我尝试了这个，我让它工作

    let BoxGeometry = SCNBox(width: 0.95, height: 0.95, length: 0.95, chamferRadius: 0.0)

    let greenMaterial = SCNMaterial()
    greenMaterial.diffuse.contents = UIImage(named: "g")
    greenMaterial.locksAmbientWithDiffuse = true;

    let redMaterial = SCNMaterial()
    redMaterial.diffuse.contents = UIImage(named: "r")
    redMaterial.locksAmbientWithDiffuse = true;


    let blueMaterial  = SCNMaterial()
    blueMaterial.diffuse.contents = UIImage(named: "b")
    blueMaterial.locksAmbientWithDiffuse = true;


    let yellowMaterial = SCNMaterial()
    yellowMaterial.diffuse.contents = UIImage(named: "y")
    yellowMaterial.locksAmbientWithDiffuse = true;


    let purpleMaterial = SCNMaterial()
    purpleMaterial.diffuse.contents = UIImage(named: "p")
    purpleMaterial.locksAmbientWithDiffuse = true;


    let WhiteMaterial = SCNMaterial()
    WhiteMaterial.diffuse.contents = UIImage(named: "w")
    WhiteMaterial.locksAmbientWithDiffuse   = true;


    BoxGeometry.materials =  [greenMaterial,  redMaterial,    blueMaterial,
    yellowMaterial, purpleMaterial, WhiteMaterial];

g是一个绿色的jpeg等等，现在它已经运行了。

SCNBox每个面上都有不同的颜色或纹理

3 个答案: