SceneKit：如何轉換SCNMaterial的內容？

Question

創建SCNNode與SCNBox，

SCNBox *wallBox = [SCNBox boxWithWidth:width height:100 length:4 chamferRadius:0]; 

SCNMaterial *allMaterial = [SCNMaterial new]; 
allMaterial.diffuse.contents = @"allwall.png"; 

SCNMaterial *smallMaterial1 = [SCNMaterial new]; 
smallMaterial1.diffuse.contents =@"bottomwall.png"; 

SCNNode *rightwall = [SCNNode nodeWithGeometry:wallBox]; 

rightwall.geometry.materials = @[smallMaterial1,allMaterial,smallMaterial1,allMaterial,allMaterial,allMaterial]; 

但質地方向的背面是錯誤的。

我想要兩個方向都是一樣的，如何把SCNMaterial的內容？如何使用「contentsTransform」？

Answer 1

我一直在使用這個答案解決了這個問題：SceneKit, flip direction of SCNMaterial

rightwall.geometry.materials = @[smallMaterial1,allMaterial,[smallMaterial1 copy],allMaterial,allMaterial,allMaterial]; 
    NSArray *allMaterial = rightwall.geometry.materials; 
    SCNMaterial *smallMaterial2= allMaterial[2]; 
    smallMaterial2.diffuse.contentsTransform = SCNMatrix4MakeScale(-1,1,1); 
    smallMaterial2.diffuse.wrapT = SCNWrapModeRepeat; 
    smallMaterial2.diffuse.wrapS = SCNWrapModeRepeat;