I'm rather new to AppKit programming and OS X programming in general so forgive me if this is a n00b question. I would like to make a windowless app which does nothing but take an image and animate it across the user's screen. If I bound myself to the window limits of my app this is easy to accomplish. How to I animate things if I want to go beyond my window/view limits?
You can't literally draw outside your window, but you can make your window borderless, transparent, and cover the whole screen or screens.
Related
I have a OSX Cocoa WebView that is a subview of view in a NSViewController. The view of the NSViewController has been added as a subview to the main window controller's view.
I am attempting to load HTML5 games into the WebView and proportionally scale them so that they fit the WebView with the least empty space possible.
I have a LOT of games I am trying to make this work for with different constraints.
For HTML5 games that were designed to auto-scale to the window, this works perfectly out of the box.
For HTML5 games that were design a fixed size for iPhone, they appear in the upper left of the WebView and take up a very small portion of the window.
For example, many games are 480x360. The window size is 1024x768 (less the title bar).
I've tried various methods for scaling up the content:
How to resize WebView according to its content?
Scale WebView in Cocoa
I've also tried using javascript to scale the content.
These definitely DO work in scaling up the content and I can get good results in filling the screen.
HOWEVER, this does NOT properly scale the position of the mouse events on the WebView canvas. Meaning, no matter how big I scale the WebView clipview which resizes content, the actual area that is clickable with the mouse is still the smaller unscaled area (as if visually things are scaling but functionally things are not).
Is there some way to scale the mouse click event for position? I can see if I click in the lower right area of the smaller bounding box, it has an affect on the larger scaled content as if I clicked the lower right area.
It seems I could add some scaling math somewhere in capturing the mouse click events but I don't understand where this can be done.
Appreciate any help.
Thanks
I need to draw an overlay consisting of lines and text on top of another application. The application in question is a 3D outside world viewpoint, and the overlay is a head up display.
I don't have access to any type of callback from the outside world application to execute draw code in it's draw loop.
Drawing directly over the application's window will result in flickering as the draw loops will not be synchronized, so to me that doesn't seem like an option.
One method I can think of is to capture the outside world application's pixels and stream them into my application, so I can draw the overlay on top in the same draw loop, but that seems very inefficient.
Is there an efficient way to draw over the outside world application without flickering?
Is it possible to draw something over the final graphics card output / at the monitor's refresh rate?
P.s. It doesn't have to be OpenGL, but the HUD is already written in OpenGL so it would make it easier.
To repeat what I said in the comments, I've come across quite a few apps that hijack the 3D api calls and inject their own code to draw stuff right at the end of each frame - steam, teamspeak, mumble. Since it's in the same application there's no flickering and you can draw directly, rather than copying the result somewhere and compositing. I've never done it before and probably won't do a good job explaining it.
A relted question is here: Overlaying on a 3D fullscreen application
Say I'm writing a 2D cad program of some sort, and I want to be able to zoom in and scroll around my document. However, I also want full control over how my document is drawn and I want an OpenGL context for which to do the drawing. How do I do this? Should I subclass NSScrollView and do something I can't quite figure out there? Should I subclass NSOpenGLView and add a pair of NSScrollers and figure out how to draw them properly? Making NSScrollers and drawing them in a way that looks good natively looks nontrivial, but NSScrollViews seem to want to own all the content you might be scrolling, rather than letting me control the size of the knob of the scroll bar and other such things. I'd be completely content with giving a document size in pixels or some such, just the most important thing to me is that when I draw to (0,0) in my OpenGL context, I draw to the corner of the window, and not into some buffer that NSScrollView owns.
Should I subclass NSOpenGLView and add a pair of NSScrollers
Yes, since scrolling a OpenGL view doesn't make sense. You want to adjust the viewing volume (i.e. the parameters defining the projection matrix), rather than moving your viewport around. And that only works if you have manual control over the scroll bars.
I am developing a document based application for Mac OS X. It's a kind of media player, but instead of playing audio or video files it is supposed to open text-files containing meta-data specifying OpenGL animations. I would like to mimic Apples QuickTime X window style. This means, i have to do all the window drawings myself, because Cocoa has no appropriate window style.
There is one thing which gives me headaches: The rounded corners usually to be found on Mac OS X windows. I tried using the borderless window mask and working some CGS magic - there are some private Apple headers which allow window shaping, but they are of course undocumented. I was able to cut rectangular holes in my windows edges, but i couldn't figure out how Apple achieves rounded corners.
Creating a transparent window and drawing the frame myself does not work, because an OpenGL viewport is always rectangular, and the only way to change it is to turn on NSOpenGLCPSurfaceOpacity for alpha transparency and using the stencil buffer or shaders to cut out the edges, which seems like a hell of a lot of overhead.
If i put an OpenGLView into a standard Cocoa window with titlebar, the bottom edges are rounded. It seems this is happening at the NSThemeFrame stage of the view hierarchy. Any ideas how this is done?
Use a layer-backed view, and do your drawing in the CALayer on an invisible window. Layers include automatic handling of rounded corners and borders.
Background for CALayer is in the Core Animation Programming Guide. To create a layer for NSView, you need to call [view setWantsLayer:YES]. You would create a CAOpenGLLayer and assign it to the view using setLayer:.
See CALayerEssentials for sample code demonstrating how to use CAOpenGLLayer among other layer types.
Since Robs suggestion didn't work and no one else contributed to the discussion i settled on using the stencil buffer to crop the windows corners. I did this by creating a texture from the windows background and rendering it into the stencil buffer, discarding all transparent pixels. Looks fine, but is slow when resizing the window :/
in my opinion the iPhone has a big advantage to other smartphones because of its intuitive, smooth and good feeling scrolling components in UIKit. I want to implement a simple game with UIKit which uses this kind of scrolling, but i can't use UIScrollView because it isn't customizable enough.
I tried to implement this scrolling myself and tried two different approaches:
I used a UIPanGestureRecognizer und moved the bounds of my custom control according to the translation the recognizer delivers me. In order to get this smooth scrolling after lifting my finger during the movement I start an animation. I use the velocity the recognizer gives me and a fixed time in order to calculate how far it should scroll after I lifted my finger. I tryed a linear movement and a ease-out movement, but both looks strange. (more later on that)
I use OnTouchMoved and OnTouchEnded to implement the scrolling. In OnTouchMove I move the bounds according to the movment of the finger. While the finger moves I calculate the difference in location and time of the current and last touch in order to calculate a velocity myself. When the finger lifts I start an animation in OnTouchEnded like in 1. but I use my self-calculated velocity instead.
Both approaches are not giving me the results I want. After lifting my finger, the scrolling is not smoothly continued. There seems to be a (sharp) bend in the celocity curve.
Has anyone an idea how apple does this smooth scrolling? My current guess is that my interpolation with two really close points is to inaccurate and doesn't take the current acceleration into account.
Thx for your thoughts!
Kie
Why don't you add a UIScrollView as handle on top of your view, without visible content. Then you can use the UIScrollViewDelegate methods to update your real view on certain actions. For example: if you capture the scrolling of the UIScrollView using scrollViewDidScroll: , you can update your visible view with the offset of the scrollview. You can use the scrollViewWillEndDragging: to start synchronizing the main view with the scrollview, and scrollViewDidEndDecelerating to stop synchronizing.
I use the same approach to scroll the background of my Animix app. It has an invisible scrollview at the bottom, to give the user the feeling he can drag the grass to the left and right to move the background.