currently I am adding my background via the method below. how can I modify the background so that it auto scrolls along with the tilemap.
- (void)setupParallax {
NSString *backgroundName = [self.tilemap propertyNamed:#"BackgroundImage"];
CCSprite *background = [CCSprite spriteWithFile:[AssetHelper
getDeviceSpecificFileNameFor:[NSString stringWithFormat:#"background-%#.png",backgroundName]]];
background.anchorPoint = ccp(0,0);
background.position = CGPointMake(0, 0);
[self addChild:background z:0];
}
You may use a CCParallaxNode. Your background and map would be children of the parallaxNode, and when you move it, its children will automatically move accordingly. Assuming the background should be behind your map, the code will look something like this.-
CCParallaxNode *voidNode = [CCParallaxNode node];
[voidNode addChild:background z:10 parallaxRatio:ccp(0.8f, 0.8f) positionOffset:ccp(0, 0)];
[voidNode addChild:map z:20 parallaxRatio:ccp(1.0f, 1.0f) positionOffset:ccp(0, 0)];
[self addChild:voidNode];
ParallaxRatio will set the speed of each layer based on ParallaxNode movement:
(1.0, 1.0) means that the map will move at the same speed that the voidNode among x and y.
(0.8, 0.8) means that the background will move 80% slower than the ParallaxNode
Related
I have been playing with CABasicAnimation and CAAnimationGroup today, and I am already in love with it. I have couple of basic animations happening, in which the circle shape shrinks and also downscale to rounded square shape, just like "Voice memo" application in iOS 7.
Below is the code for it.
CABasicAnimation *corner = [CABasicAnimation animationWithKeyPath:#"cornerRadius"];
corner.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear];
corner.fromValue = [NSNumber numberWithFloat:recordingShape.layer.cornerRadius];
corner.toValue = [NSNumber numberWithFloat:30.0f];
corner.duration = 1.0;
//shrinking - scaling
CABasicAnimation* shrink = [CABasicAnimation animationWithKeyPath:#"transform.scale"];
shrink.toValue = [NSNumber numberWithDouble:0.5];
shrink.duration = 0.5;
// Two animations concurrently so set up CAAnimationGroup
CAAnimationGroup *group = [CAAnimationGroup animation];
[group setDuration:0.5];
[group setAnimations:[NSArray arrayWithObjects:shrink, corner, nil]];
// Animate the layer
[[recordingShape layer] addAnimation:group forKey:#"bounceAndFade"];
The animation occurs nicely as expected, but after animation it goes back to its original state as round circle, could anyone guide me as of how can I persist the layer's frame?
Thanks.
Well I Didn't know you could setup a delegate for the CAAnimationGroup group, hence I change the actual cornerRadius and transform at animationDidStop call.
I am working on a OSX/Cocoa graphics application which (for performance reasons) I would like to render at 640x480 when the user selects "full screen" mode. For what it's worth, the content is a custom NSView which draws using openGL.
I understand that rather than actually change the user's resolution, it's preferable to change the backbuffer (as explained on another SO question here: Programmatically change resolution OS X).
Following that advice, I end up with the following two methods (see below) to toggle between fullscreen and windowed. The trouble is that when I go fullscreen, the content does indeed render at 640x480 but is not scaled (IE it appears as if we stayed at the window's resolution and "zoomed" into a 640x480 corner of the render).
I'm probably missing something obvious here - I suppose I could translate the render according to the actual screen resolution to "center" it, but that seems overcomplicated?
- (void)goFullscreen{
// Bounce if we're already fullscreen
if(_isFullscreen){return;}
// Save original size and position
NSRect frame = [self.window.contentView frame];
original_size = frame.size;
original_position = frame.origin;
NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithBool:NO],NSFullScreenModeAllScreens,
nil];
// In lieu of changing resolution, we set the backbuffer to 640x480
GLint dim[2] = {640, 480};
CGLSetParameter([[self openGLContext] CGLContextObj], kCGLCPSurfaceBackingSize, dim);
CGLEnable ([[self openGLContext] CGLContextObj], kCGLCESurfaceBackingSize);
// Go fullscreen!
[self enterFullScreenMode:[NSScreen mainScreen] withOptions:options];
_isFullscreen=true;
}
- (void)goWindowed{
// Bounce if we're already windowed
if(!_isFullscreen){return;}
// Reset backbuffer
GLint dim[2] = {original_size.width, original_size.height};
CGLSetParameter([[self openGLContext] CGLContextObj], kCGLCPSurfaceBackingSize, dim);
CGLEnable ([[self openGLContext] CGLContextObj], kCGLCESurfaceBackingSize);
// Go windowed!
[self exitFullScreenModeWithOptions:nil];
[self.window makeFirstResponder:self];
_isFullscreen=false;
}
Update
Here's now to do something similar to datenwolf's suggestion below, but not using openGL (useful for non-gl content).
// Render into a specific size
renderDimensions = NSMakeSize(640, 480);
NSImage *drawIntoImage = [[NSImage alloc] initWithSize:renderDimensions];
[drawIntoImage lockFocus];
[self drawViewOfSize:renderDimensions];
[drawIntoImage unlockFocus];
[self syphonSendImage:drawIntoImage];
// Resize to fit preview area and draw
NSSize newSize = NSMakeSize(self.frame.size.width, self.frame.size.height);
[drawIntoImage setSize: newSize];
[[NSColor blackColor] set];
[self lockFocus];
[NSBezierPath fillRect:self.frame];
[drawIntoImage drawAtPoint:NSZeroPoint fromRect:self.frame operation:NSCompositeCopy fraction:1];
[self unlockFocus];
Use a FBO with a texture of the desired target resolution attached and render to that FBO/texture in said resolution. Then switch to the main framebuffer and draw a full screen quad using the texture rendered to just before. Use whatever magnification filter you like best. If you want to bring out the big guns you could implement a Lancosz / sinc interpolator in the fragment shader to upscaling the intermediary texture.
Hey, I'm having a performance problem with CALayers in a layer backed NSView inside an NSScrollView. I've got a scroll view that I populate with a bunch of CALayer instances, stacked one on top of the next. Right now all I am doing is putting a border around them so I can see them. There is nothing else in the layer.
Performance seems fine until I have around 1500 or so in the scroll view. When I put 1500 in, the performance is great as I scroll down the list, until I get to around item 1000. Then very suddenly the app starts to hang. It's not a gradual slowdown which is what I would expect if it was just reaching it's capacity. It's like the app hits a brick wall.
When I call CGContextFillRect in the draw method of the layers, the slowdown happens around item 300. I'm assuming this has something to do with maybe the video card memory filling up or something? Do I need to do something to free the resources of the CALayers when they are offscreen in my scroll view?
I've noticed that if I don't setNeedsDisplay on my layers, I can get to the end of 1500 items without slowdowns. This is not a solution however, as I have some custom drawing that I must perform in the layer. I'm not sure if that solves the problem, or just makes it show up with a greater number of items in the layer. Ideally I would like this to be fully scalable with thousands of items in the scroll view (within reason of course). Realistically, how many of these empty items should I expect to be able to display in this way?
#import "ShelfView.h"
#import <Quartz/Quartz.h>
#implementation ShelfView
- (void) awakeFromNib
{
CALayer *rootLayer = [CALayer layer];
rootLayer.layoutManager = self;
rootLayer.geometryFlipped = YES;
[self setLayer:rootLayer];
[self setWantsLayer:YES];
int numItemsOnShelf = 1500;
for(NSUInteger i = 0; i < numItemsOnShelf; i++) {
CALayer* shelfItem = [CALayer layer];
[shelfItem setBorderColor:CGColorCreateGenericRGB(1.0, 0.0, 0.0, 1.0)];
[shelfItem setBorderWidth:1];
[shelfItem setNeedsDisplay];
[rootLayer addSublayer:shelfItem];
}
[rootLayer setNeedsLayout];
}
- (void)layoutSublayersOfLayer:(CALayer *)layer
{
float y = 10;
int totalItems = (int)[[layer sublayers] count];
for(int i = 0; i < totalItems; i++)
{
CALayer* item = [[layer sublayers] objectAtIndex:i];
CGRect frame = [item frame];
frame.origin.x = self.frame.size.width / 2 - 200;
frame.origin.y = y;
frame.size.width = 400;
frame.size.height = 400;
[CATransaction begin];
[CATransaction setAnimationDuration:0.0];
[item setFrame:CGRectIntegral(frame)];
[CATransaction commit];
y += 410;
}
NSRect thisFrame = [self frame];
thisFrame.size.height = y;
if(thisFrame.size.height < self.superview.frame.size.height)
thisFrame.size.height = self.superview.frame.size.height;
[self setFrame:thisFrame];
}
- (BOOL) isFlipped
{
return YES;
}
#end
I found out it was because I was filling each layer with custom drawing, they seemed to all be cached as separate images, even though they shared a lot of common data, so I switched to just creating a dozen CALayers, filling their "contents" property, and adding them as sublayers to a main layer. This seemed to make things MUCH zippier.
I have a CAShapeLayer and it has to do a simple task of moving on the screen, guided by the user's finger.
The problem is that the movement is too slow. The layer does move, but there is a lag and it feels slow.
I have another test app where an UIImage is moved and there is no lag at all and the image moves instantly.
What can I do to overcome this?
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
currentPoint = [[touches anyObject] locationInView:self];
}
- (void) touchesMoved:(NSSet*)touches withEvent:(UIEvent*)event
{
CGPoint activePoint = [[touches anyObject] locationInView:self];
CGPoint newPoint = CGPointMake(activePoint.x - currentPoint.x,activePoint.y - currentPoint.y);
curLayer.position = CGPointMake(shapeLayer.position.x+newPoint.x,shapeLayer.position.y+newPoint.y);
currentPoint = activePoint;
}
Thanks!
Keep in mind that when you set the position on a layer (assuming it's not the root layer of a UIView on which actions are disabled by default), it implicitly animates to the new position, which takes 0.25 seconds. If you want to make it snappier, temporarily disable actions on the layer like this:
- (void) touchesMoved:(NSSet*)touches withEvent:(UIEvent*)event
{
CGPoint activePoint = [[touches anyObject] locationInView:self];
CGPoint newPoint = CGPointMake(activePoint.x -
currentPoint.x,activePoint.y - currentPoint.y);
[CATransaction begin];
[CATransaction setDisableActions:YES];
curLayer.position = CGPointMake(shapeLayer.position.x +
newPoint.x, shapeLayer.position.y + newPoint.y);
[CATransaction commit];
currentPoint = activePoint;
}
This should cause it to jump to the new position rather than animate. If that doesn't help, then let me take a look at your layer init code so I can see what properties and dimensions it has. Properties such as cornerRadius, for example, can affect performance.
Try setting shouldRasterize to YES on your CAShapeLayer, particularly if it is usually drawn at the same scale. If your app runs on high-DPI devices, you may also need to set rasterizationScale to match the layer’s contentsScale.
While rasterizing your shape can make it faster to move the shape around, you’ll probably want to temporarily disable rasterization while you’re animating the layer’s path or size.
I have a layer backed view, I am trying to add subLayers roughly sized around 300 X 270 (in pixels) to it.
The sublayers' count may reach 1000 to 2000, not to mention each sublayer is again scalable to roughly 4280 X 1500 or more for starters.
So the problem is obviously that of a GPU constraint.
After adding around 100 subLayers sized 300 X 270 , there is a warning image is too large for GPU, ignoring and that is messing with the layer display.
The solution for such a problem (from some mailing lists) was to use CATiledLayer, but I can't make use of the tiledLayer due to the complex requirement of the subLayers' display.
Is there a possibility of removing the subLayers which don't fall under VisibleRect of the view?
I tried to removeFromSuperlayer and then add it whenever required, there's always a crash when I try to add the subLayer back.
How can I do this?
I am adding sublayer twice (I need to change it) but for now just for the gist of the code:
-(IBAction)addLayer:(id)sender
{
Layer *l = [[Layer alloc] init];
CALayer *layer = [l page];
[contentArray addObject:page];
[drawLayer addSublayer:layer];
[self layout];
}
-(void)layout
{
NSEnumerator *pageEnumr = [contentArray objectEnumerator];
float widthMargin = [self frame].size.width;
CGRect rect;
float zoom = [self zoomFactor];
while(obj = [contentEnmr nextObject] )
{
[obj setZoomFactor:zoom];
CALayer *pg =(CALayer *)[obj page] ;
rect = pg.bounds;
if ( x + pg.bounds.size.width > widthMargin )
{
x = xOffset;
y += rect.size.height + spacing ;
}
rect.origin = CGPointMake(x,y);
[obj changeBounds];
NSRect VisibleRect = [self visibleRect];
NSRect result = NSIntersectionRect(VisibleRect,NSRectFromCGRect( rect));
if( NSEqualRects (result ,NSZeroRect) )
{
[pg removeFromSuperlayer];
}else
{
[drawLayer addSublayer:pg];
[pg setFrame:rect];
[pg setNeedsDisplay];
}
x += ( rect.size.width + spacing);
}
NSRect viewRect = [self frame];
if(viewRect.size.height < ( y + rect.size.height + spacing ) )
viewRect.size.height = ( y + rect.size.height + spacing) ;
[self setFrameSize: viewRect.size];
}
#interface Layer : NSObject {
CALayer *page;
}
#property (retain) CALayer *page;
Have a look at the PhotoScroller application included as part of the WWDC conference. It demonstrates how to zoom and scroll through a very large image by loading only portions of that image that are currently visible.
Also check out this discussion.
You'll need to do what NSTableView and UITableView do, and manage the addition / removal of layers yourself whenever the visible rect changes. Subscribe to the boundsDidChange noitification of the enclosing scroll view's clip view (I'm assuming that the reason some of the layer is offscreen is that it's enclosed in a scroll view):
- (void) viewDidMoveToSuperview
{
NSClipView* clipView = [[self enclosingScrollView] contentView];
[clipView setPostsBoundsChangedNotifications:YES];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(clipViewBoundsDidChange:)
name:NSViewBoundsDidChangeNotification
object:clipView];
}
and then write a clipViewBoundsDidChange: method that adds and removes sublayers as needed. You may also want to cache and reuse invalidated layers to cut down on allocations. Take a look at the way UITableView and NSTableView interact with their dataSource object for some ideas about how to design the interface for this.
CATiledLayer solves this problem the content of a layer --- ie, whatever you set its contents property or draw into its graphics context directly. It won't do this for sublayers, in fact I think you're advised not to add sublayers to a CATiledLayer at all, as this interferes with its drawing behaviour.