I would like to create an effect than an image zooms up from a thumbnail size to full screen.
I am not sure what's the right steps to achieve this. Should I create a transparent full screen window and animate a layer on top of it?
Take a look at this CoreGraphics example. Specifically, take a look at the "grow" and "shrink" animations. That's how Apple does it, and that's what you'll want to do too.
Your solution of a transparent window with a CALayer inside is probably the best supported way to do it.
One thing that seems like it should be a good solution (at least it's the first thing I thought of when I wanted to do this) but isn't is NSView's enterFullScreenMode:withOptions:. If memory serves, it was originally meant to do what you're talking about here, but the animation was taken out and it generally doesn't work that well now.
Related
Capturing an image of an off-screen window with CGWindowListCreateImage is a common way to create QuickLook style zoom-in animations, but this seems create an image with the wrong background colour, slightly lighter than the real window.
This causes a flash at the end of the animation which kind of ruins the effect.
Does anyone have any idea why this happens and what can be done about it?
EDIT: I created a demonstration app for this problem. It is a bit large and complex for a Stack Overflow question, but the relevant code is probably in the ZoomingWindow.m methods takeSnapshot and makeAndPrepareSnapshotWindow.
Setting the window appearance to textured in Interface Builder fixed this. Of course that also changes the color of the window, but that is acceptable in this particular case.
Basically I have an opaque View covering a screen, and I want to build an animation that is something like a (perfect circular) hole in the view forming in the center (so to reveal whats underneath) and expanding outwards.
I'm thinking that there could be a few creative ways to get this done, and that perhaps the most corresponding CSS property to play with would be 'clip-path'. If that is the case, I don't believe ReactNative Views offer that, and 3rd party libraries w/ SVG & clipping features seem like they wouldn't play well with Animating the effect.
Any ideas much appreciated!
You could use https://github.com/react-native-community/react-native-svg !
The library supports SVG's better and allows you to animate with Clip-path!
Hi I'm looking to do the following:
For a game, Create some effects based on the current view.
The code needs to grab part of a view then manipulate it.
One I need is "glass", so when the character walks behind the glass(or where the glass should be), the code will grab the image behind the glass and stretch it and reprint it where the glass should be, to give the effect of walking behind a lens.
What is the best way to do this?
I've never tried any thing like this before, so any help will be great!
I think you're asking about the image manipulation capabilities of the cocoa framework, in which case I reccomend looking into CoreImage:
http://developer.apple.com/library/mac/#documentation/graphicsimaging/Conceptual/CoreImaging/ci_intro/ci_intro.html#//apple_ref/doc/uid/TP30001185
The NSBox draws on top of the player view, the resulting composition gets a CIFilter (distortion) applied to it before drawing.
I have an NSMutableArray of jpg images and I want to be able to touch and, moving my finger from right to left, move through the array of images in order. I've been reading about UIScrollView, but I'm not sure if this accomplishes what I am looking for. It seems to me that UIScrollView is more used for viewing an object that is too large to be displayed entirely on the screen and you need to be able to move to see every part of the object. I need to move to an entirely new image, the next image in my array. What is the best way to go about this?
You certainly can use a UIScrollView for what you want. A scroll view can be used, as you noted, to scroll an area that is too large for the screen. However, you can also use it to scroll through "pages". This is really the best way to do what you want, short of rolling your won scroll view.
There is a property of UIScrollView, called pagingEnabled, which you'll want to set to YES. I suggest that you give it a try. Also, have a look at the UIScrollView documentation and the Scroll View programming guide. It will tell you all that you need to know about UIScrollViews. Also, remember that for proper memory management, you'll want to only load three images at any given time. See this answer that I wrote for more information on that, and on UIScrollViews in general.
I've been banging my head about this seemingly easy task and I could really use some help.
I have a wide Image loaded in the gui (using the designer..) and I want to be able to draw only a portion of it, a rectangle.
I need to be able to change this rectangle position over the large image, in order to draw a different part of the larger image at will. In this process the rect must maintain its size.
Using the Ui::MainWindow object I'm able to access the label holding the image and a solution that involves using this option is preferred (in order to keep up with the rest of the code I've already written )
Any solution will be much appreciated :)
Thanks,
Itamar
I would definitely (for ease of use) just place an empty label as placeholder in Designer.
Then implement the paintEvent for this label (delegate it to your own method). You'll have also have to look into QPainter, QPixMap, etc... Should be doable based on these hints and the documentation.
If you want more, I suggest you provide a small code snippet to work upon.
If you want to do this more or less purely through designer, you could put a QScrollArea where you want the portion of the image to appear. If you set the scroll area's scrollbar policy to be never shown, you can then manually change what part is visible via the scroll area widget. However, this would probably be more complex that creating a derived widget and reimplementing the paint function.