SceneKit, SCNMaterial change direction

Question

extremely new to SceneKit, so just seek help here:

I have SCNSphere with a camera in the center of it

I create SCNMaterial, doubleSided and assign it to a sphere

Since the camera is in the center, the image looks upright, which, if there is text inside, will completely ruin things.

So, how can I flip the material or image (although later it will be frames from the video), any other suggestion is welcome.

This solution, btw, fails, normalImage is applied as material (but the image is upside down when viewed from inside the sphere), but assigning flippedImage does not produce any material (white screen)

    let normalImage = UIImage(named: "text2.png")
    let ciimage = CIImage(CGImage: normalImage!.CGImage!)
    let flippeCIImage = ciimage.imageByApplyingTransform(CGAffineTransformMakeScale(-1, 1))
    let flippedImage = UIImage(CIImage: flippeCIImage, scale: 1.0, orientation: .Left)

    sceneMaterial.diffuse.contents = flippedImage
    sceneMaterial.specular.contents = UIColor.whiteColor()
    sceneMaterial.doubleSided = true
    sceneMaterial.shininess = 0.5

Answer 1

node ( ) , SCNMaterialProperty contentsTransform.

material.diffuse.contentsTransform = SCNMatrix4MakeScale(1,-1,1);
material.diffuse.wrapT = SCNWrapModeRepeat; //or translate contentsTransform by (0,1,0);

Answer 2

, , node, :

sphereNode.scale = SCNVector3Make (-1, 1, 1)

Answer 3

:

material.diffuse.contentsTransform = SCNMatrix4Translate(SCNMatrix4MakeScale(-1, 1, 1), 1, 0, 0)

:

material.diffuse.contentsTransform = SCNMatrix4Translate(SCNMatrix4MakeScale(1, -1, 1), 0, 1, 0)

Answer 4

, . , , [material].diffuse.contents; , , :

// Define the matrices that perform the two orientation variants
SCNMatrix4 flip_horizontal;
flip_horizontal = SCNMatrix4Translate(SCNMatrix4MakeScale(-1, 1, 1), 1, 0, 0);
SCNMatrix4 flip_vertical;
flip_vertical = SCNMatrix4Translate(SCNMatrix4MakeScale(1, -1, 1), 0, 1, 0);

// Create the material objects for each cube, and assign an image as the contents
self.source_material = [SCNMaterial material];
self.source_material.diffuse.contents = [UIImage imageNamed:@"towelface.png"];
self.mirror_material = [SCNMaterial material];
self.mirror_material.diffuse.contents = self.source_material.diffuse.contents;

( ):

// PortraitOpposingDown
    [self.mirror_material.diffuse setContentsTransform:SCNMatrix4Mult(self.source_material.diffuse.contentsTransform, flip_vertical)];
        [self.source_material.diffuse setContentsTransform:SCNMatrix4Mult(self.mirror_material.diffuse.contentsTransform, flip_horizontal)]; 

// PortraitFacingDown
    [self.source_material.diffuse setContentsTransform:SCNMatrix4Mult(self.source_material.diffuse.contentsTransform, flip_vertical)];
    [self.mirror_material.diffuse setContentsTransform:SCNMatrix4Mult(self.source_material.diffuse.contentsTransform, flip_horizontal)];

// PortraitOpposingUp
    [self.source_material.diffuse setContentsTransform:SCNMatrix4Mult(self.source_material.diffuse.contentsTransform, flip_horizontal)];

// PortraitFacingUp
    [self.mirror_material.diffuse setContentsTransform:SCNMatrix4Mult(self.source_material.diffuse.contentsTransform, flip_horizontal)];

:

[cube[0] insertMaterial:self.source_material atIndex:0];
[cube[1] insertMaterial:self.mirror_material atIndex:0];

, (, ), , insertMaterial:atIndex; contentsTransform. , ; , , , , AVCaptureVideoDataOutputSampleBufferDelegate (CreateCGImageFromCVPixelBuffer), CGImage CVPixelBuffer:

- (void)captureOutput:(AVCaptureOutput *)output didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection
{
    CVPixelBufferRef pixelBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
    CGImageRef cgImage;
    CreateCGImageFromCVPixelBuffer(pixelBuffer, &cgImage);
    UIImage *image = [UIImage imageWithCGImage:cgImage];
    dispatch_async(dispatch_get_main_queue(), ^{
        self.source_material.diffuse.contents = image;
        [cube[0] replaceMaterialAtIndex:0 withMaterial:self.source_material];
        self.mirror_material.diffuse.contents = self.source_material.diffuse.contents;
        [cube[1] replaceMaterialAtIndex:0 withMaterial:self.mirror_material];
        });
        CGImageRelease(cgImage);
}

, , . , , .