catransform3d

问题 This has been asked before, but there is no sample code to be found on stackoverflow and no proper solutions as far as I'm aware. I have a solution, but it looks crap. I'd be grateful for any input and modifications to get a more realistic 3D door open / book cover animation. Aim is to have an animation between UIViewControllers so that you get the effect as if you were opening a door or a book cover. ViewController 2 is static and in the background. Above it you place ViewController 1 which

问题 This has been asked before, but there is no sample code to be found on stackoverflow and no proper solutions as far as I'm aware. I have a solution, but it looks crap. I'd be grateful for any input and modifications to get a more realistic 3D door open / book cover animation. Aim is to have an animation between UIViewControllers so that you get the effect as if you were opening a door or a book cover. ViewController 2 is static and in the background. Above it you place ViewController 1 which

问题 I'm rotating an UIView along the x axis using CATransform3DMakeRotation using the below code: float radians = DegreesToRadians(30); [UIView animateWithDuration:0.15 animations:^{ self.moveControlView.layer.transform = CATransform3DMakeRotation(radians,1,0,0); }]; The rotation is applied always in the same versus ( clockwise ). I want to rotate the UIView in the opposite versus. In order to achieve my goal I've tried: Set a negative angle (-30) Set the angle to 330 But the versus of the

问题 I want to draw an image like the following in a certain orientation. Assume that the device lies flat on a table the image above shows how the arrow should be drawn. The angle between the device and the table is called alpha and it is zero in this case. The arrow points straight to a predefined location point. If you rotate the device on the table the arrow will point alway to the target direction just like a compass. I did the update of the image position with the following code in 2D space:

问题 i have a problem with CATransform3DTranslate. i concatenating it with CATransform3D with the code from KennyTM here i measured the coordinate using Photoshop. here is my complete code : background.image = UIImage(named: "backgroundtest") gambar.image = UIImage(named: "imagetest") gambar.layer.anchorPoint = CGPointZero var translate = CATransform3DIdentity translate = CATransform3DTranslate(translate, -160, -85.5, 0) var perspective = CATransform3DIdentity perspective = compute_transform

问题 It is known that the zPosition of the layers only determines which layer cover up which layer. Whether it is a zPosition of 10 or 1000 won't affect its position. That is, unless if we use CATransformLayer to contain those layers, then the zPosition of those layers will affect the layers' position. However, the following code running in iOS 5.1.1 does make the zPosition alter the position of the layers... you can try it in a new Single View App, and add the following code to ViewController.m .

问题 Please go through the images. So this is the code which I got from some online source and it does transform my object. Besides that, I understood nothing at all. I am new to CATransform3D and want to know exactly how it works. CATransform3D transform = CATransform3DIdentity; transform.m34 = 1.0 / -500; transform = CATransform3DRotate(transform, 45.0f * M_PI / 180.0f, 0, 1, 0.0f); _bgView.layer.transform = transform; I want to know how did this code run? Why did we set some value in m34? I

问题 I am slowly getting more serious about Core Animation and would greatly appreciate an explanation composed of short words spoken (typed?) slowly explaining CATransform3DIdentity and why the following code does what it does (flips the layer around in '3D' space) kFaceUpTransform = kFaceDownTransform = CATransform3DIdentity; // Construct a 180-degree rotation matrix: kFaceDownTransform.m11 = kFaceDownTransform.m33 = -1; On second thought, type quickly and use multisyllabic words to your hearts

问题 What's the meaning of m34 of the structure CATransform3D, I only know it can change the perspective, but what's the meaning when the value is -0.001 and 0.001? 回答1: You can find the full details here. Note that Apple uses the reversed multiplication order for projection (relative to the given link) so all matrix multiplications are reversed and all matrices are transposed. A short description of the meaning: m34 = 1/z distance to projection plane (the 1/e z term in the reference link) + for

问题 How do I calculate the Rotation in Radians around Z-axis by giving a CATransform3D struct as the input? basically what I need is the other way round of CATransform3DMakeRotation . 回答1: It depends on what axis you are doing the rotation on. Rotation about the z-axis is represented as: a = angle in radians x' = x*cos.a - y*sin.a y' = x*sin.a + y*cos.a z' = z ( cos.a sin.a 0 0) (-sin.a cos.a 0 0) ( 0 0 1 0) ( 0 0 0 1) so angle should be a = atan2(transform.m12, transform.m11); Rotation about x