I'm using BCTabBarController in my app, and I'm trying to customize it so that it uses Core Graphics to highlight the images automatically, so that I don't need four copies of each image. (Retina, Retina-selected, Legacy, Legacy-selected)
User Ephraim has posted a great starting point for this, but it returns legacy sized images. I've played with some of the settings, but I'm not very familiar with Core Graphics, so I'm shooting in the dark.
Ephraim's Code:
- (UIImage *) imageWithBackgroundColor:(UIColor *)bgColor
shadeAlpha1:(CGFloat)alpha1
shadeAlpha2:(CGFloat)alpha2
shadeAlpha3:(CGFloat)alpha3
shadowColor:(UIColor *)shadowColor
shadowOffset:(CGSize)shadowOffset
shadowBlur:(CGFloat)shadowBlur {
UIImage *image = self;
CGColorRef cgColor = [bgColor CGColor];
CGColorRef cgShadowColor = [shadowColor CGColor];
CGFloat components[16] = {1,1,1,alpha1,1,1,1,alpha1,1,1,1,alpha2,1,1,1,alpha3};
CGFloat locations[4] = {0,0.5,0.6,1};
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGGradientRef colorGradient = CGGradientCreateWithColorComponents(colorSpace, components, locations, (size_t)4);
CGRect contextRect;
contextRect.origin.x = 0.0f;
contextRect.origin.y = 0.0f;
contextRect.size = [image size];
//contextRect.size = CGSizeMake([image size].width+5,[image size].height+5);
// Retrieve source image and begin image context
UIImage *itemImage = image;
CGSize itemImageSize = [itemImage size];
CGPoint itemImagePosition;
itemImagePosition.x = ceilf((contextRect.size.width - itemImageSize.width) / 2);
itemImagePosition.y = ceilf((contextRect.size.height - itemImageSize.height) / 2);
UIGraphicsBeginImageContext(contextRect.size);
CGContextRef c = UIGraphicsGetCurrentContext();
// Setup shadow
CGContextSetShadowWithColor(c, shadowOffset, shadowBlur, cgShadowColor);
// Setup transparency layer and clip to mask
CGContextBeginTransparencyLayer(c, NULL);
CGContextScaleCTM(c, 1.0, -1.0);
CGContextClipToMask(c, CGRectMake(itemImagePosition.x, -itemImagePosition.y, itemImageSize.width, -itemImageSize.height), [itemImage CGImage]);
// Fill and end the transparency layer
CGContextSetFillColorWithColor(c, cgColor);
contextRect.size.height = -contextRect.size.height;
CGContextFillRect(c, contextRect);
CGContextDrawLinearGradient(c, colorGradient,CGPointZero,CGPointMake(contextRect.size.width*1.0/4.0,contextRect.size.height),0);
CGContextEndTransparencyLayer(c);
//CGPointMake(contextRect.size.width*3.0/4.0, 0)
// Set selected image and end context
UIImage *resultImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
CGColorSpaceRelease(colorSpace);
CGGradientRelease(colorGradient);
return resultImage;
}
To implement this code, I've added a category to UIImage in my project, and then made the following changes to BCTab.h:
- (id)initWithIconImageName:(NSString *)imageName {
if (self = [super init]) {
self.adjustsImageWhenHighlighted = NO;
self.background = [UIImage imageNamed:#"BCTabBarController.bundle/tab-background.png"];
self.rightBorder = [UIImage imageNamed:#"BCTabBarController.bundle/tab-right-border.png"];
self.backgroundColor = [UIColor clearColor];
// NSString *selectedName = [NSString stringWithFormat:#"%#-selected.%#",
// [imageName stringByDeletingPathExtension],
// [imageName pathExtension]];
UIImage *defImage = [UIImage imageNamed:imageName];
[self setImage:[defImage imageWithBackgroundColor:[UIColor lightGrayColor] shadeAlpha1:0.4 shadeAlpha2:0.0 shadeAlpha3:0.6 shadowColor:[UIColor blackColor] shadowOffset:CGSizeMake(0.0, -1.0f) shadowBlur:3.0] forState:UIControlStateNormal];
[self setImage:[defImage imageWithBackgroundColor:[UIColor redColor] shadeAlpha1:0.4 shadeAlpha2:0.0 shadeAlpha3:0.6 shadowColor:[UIColor blackColor] shadowOffset:CGSizeMake(0.0, -1.0f) shadowBlur:3.0] forState:UIControlStateSelected];
}
return self;
}
How can I use Ephraim's code to work correctly with Retina display?
After digging around the internet, a Google search lead me back to StackOverflow. I found this answer to this question which discusses a different method which should be used to set the scale factor of the UIImageGraphicsContext when it is initialized.
UIGraphicsBeginImageContext(contextRect.size); needs to be changed to UIGraphicsBeginImageContextWithOptions(contextRect.size, NO, scale);, where "scale" is the
value of the scale you want to use. I grabbed it from [[UIScreen mainScreen] scale].
Related
I am trying to achieve this glowing effect for a UILabel as shown below :
I have subclassed UILabel , and created a custom label class that adds an outer shadow.
Edit : Here's the code i have used for outer shadow/glow in my custom Label class :
- (void)drawTextInRect:(CGRect)rect {
UIColor *insideColor;
UIColor *blurColor;
CGContextRef ctx = UIGraphicsGetCurrentContext();
insideColor =[UIColor colorWithRed:255/255.0 green:255/255.0 blue:191/255.0 alpha:1];
blurColor =[UIColor orangeColor];
CGContextSetFillColorWithColor(ctx, insideColor.CGColor);
CGContextSetShadowWithColor(ctx, CGSizeMake(0, 0), self.glowAmount, blurColor.CGColor);
CGContextSetTextDrawingMode(ctx, kCGTextFillStroke);
[self.text drawInRect:self.bounds withFont:self.font lineBreakMode:self.lineBreakMode alignment:self.textAlignment];
}
But this gives me the following result
As you can see this lacks the desired effect because of the missing inner shadow. Can anyone suggest how to achieve this?
Thanks!
I referred the answer by Steven XM for Inner Shadow in UILabel . It was a great help.
Here's what i have done to achieve the result but i want to know if this can be more optimized?
-(void)setInnerGlowWithColor:(UIColor *)shadowColor fillColor:(UIColor *)insideColor inRect:(CGRect)rect
{
UIFont *font = self.font;
// UIFont *font = [UIFont fontWithName:#"HelveticaNeue-Bold" size:17];
CGSize fontSize = [self.text sizeWithFont:font];
/**** Following are the steps to create an inside shadow ****/
// STEP 1 : Create a image mask of your text.
CGImageRef mask = [self createMaskWithSize:rect.size shape:^{
[[UIColor blackColor] setFill];
CGContextFillRect(UIGraphicsGetCurrentContext(), rect);
[[UIColor whiteColor] setFill];
// custom shape goes here
[self.text drawAtPoint:CGPointMake((self.bounds.size.width/2)-(fontSize.width/2), 0) withFont:font];
}];
// STEP 2 : Invert that mask.
CGImageRef cutoutRef = CGImageCreateWithMask([self blackSquareOfSize:rect.size].CGImage, mask);
CGImageRelease(mask);
UIImage *cutout = [UIImage imageWithCGImage:cutoutRef scale:[[UIScreen mainScreen] scale] orientation:UIImageOrientationUp];
CGImageRelease(cutoutRef);
// STEP 3 : Use this inverted mask to draw a shadow around the inside edges of the text.
CGImageRef shadedMask = [self createMaskWithSize:rect.size shape:^{
[[UIColor whiteColor] setFill];
CGContextFillRect(UIGraphicsGetCurrentContext(), rect);
//****************For inner shadow/glow
NSLog(#"in custom label----> %f",self.glowAmount);
CGContextSetShadowWithColor(UIGraphicsGetCurrentContext(), CGSizeMake(0, 0), self.glowAmount, shadowColor.CGColor);
[cutout drawAtPoint:CGPointZero];
}];
// STEP 4 : Create negative image
UIGraphicsBeginImageContextWithOptions(rect.size, NO, 0);
[shadowColor setFill];
// custom shape goes here
[self.text drawAtPoint:CGPointMake((self.bounds.size.width/2)-(fontSize.width/2), 0) withFont:font];
UIImage *negative = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
// STEP 5 : Create the shadow image
CGImageRef innerShadowRef = CGImageCreateWithMask(negative.CGImage, shadedMask);
CGImageRelease(shadedMask);
UIImage *innerShadow = [UIImage imageWithCGImage:innerShadowRef scale:[[UIScreen mainScreen] scale] orientation:UIImageOrientationUp];
CGImageRelease(innerShadowRef);
// STEP 6 : Draw actual text
[insideColor setFill];
[self.text drawAtPoint:CGPointMake((self.bounds.size.width/2)-(fontSize.width/2), 0) withFont:font];
// STEP 7 : Finally apply the shadow image
[innerShadow drawAtPoint:CGPointZero];
}
- (UIImage*)blackSquareOfSize:(CGSize)size {
UIGraphicsBeginImageContextWithOptions(size, NO, 0);
[[UIColor blackColor] setFill];
CGContextFillRect(UIGraphicsGetCurrentContext(), CGRectMake(0, 0, size.width, size.height));
UIImage *blackSquare = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return blackSquare;
}
- (CGImageRef)createMaskWithSize:(CGSize)size shape:(void (^)(void))block {
UIGraphicsBeginImageContextWithOptions(size, NO, 0);
block();
CGImageRef shape = [UIGraphicsGetImageFromCurrentImageContext() CGImage];
UIGraphicsEndImageContext();
CGImageRef mask = CGImageMaskCreate(CGImageGetWidth(shape),
CGImageGetHeight(shape),
CGImageGetBitsPerComponent(shape),
CGImageGetBitsPerPixel(shape),
CGImageGetBytesPerRow(shape),
CGImageGetDataProvider(shape), NULL, false);
return mask;
}
My iPad app has a navigation where I show screenshots of the different pages and because I want to show more than one screenshot at once I scale the container to around 24% of the original screenshots (1024x768).
- (void) loadView
{
// get landscape screen frame
CGRect screenFrame = [UIScreen mainScreen].bounds;
CGRect landscapeFrame = CGRectMake(0, 0, screenFrame.size.height, screenFrame.size.width);
UIView *view = [[UIView alloc] initWithFrame:landscapeFrame];
view.backgroundColor = [UIColor grayColor];
self.view = view;
// add container view for 2 images
CGRect startFrame = CGRectMake(-landscapeFrame.size.width/2, 0, landscapeFrame.size.width*2, landscapeFrame.size.height);
container = [[UIView alloc] initWithFrame:startFrame];
container.backgroundColor = [UIColor whiteColor];
// add image 1 (1024x768)
UIImage *img1 = [UIImage imageNamed:#"01.jpeg"];
UIImageView *img1View = [[UIImageView alloc] initWithImage:img1];
[container addSubview:img1View];
// add image 2 (1024x768)
UIImage *img2 = [UIImage imageNamed:#"02.jpeg"];
UIImageView *img2View = [[UIImageView alloc] initWithImage:img2];
// move img2 to the right of img1
CGRect newFrame = img2View.frame;
newFrame.origin.x = 1024.0;
img2View.frame = newFrame;
[container addSubview:img2View];
// scale to 24%
container.transform = CGAffineTransformMakeScale(0.24, 0.24);
[self.view addSubview:container];
}
but when I scale images with "small" text it looks sth like this:
I have to use the big screenshots because if a user taps the image it should scale to 100% and be crispy clear.
is there a way how I can scale the images "smoothly" (on the fly) without ruining performance?
it would be enough to have two versions: the full-px one and another for the 24% version.
The reason the scaled-down image looks crappy is it's being scaled in OpenGL, which is using fast-but-low-quality linear interpolation. As you probably know, UIView is built on top of CALayer, which is in turn a sort of wrapper for OpenGL textures. Because the contents of the layer reside in the video card, CALayer can do all of its magic on the GPU, independent of whether the CPU is busy loading a web site, blocked on disk access, or whatever. I mention this only because it's useful to pay attention to what's actually in the textures inside your layers. In your case, the UIImageView's layer has the full 1024x768 bitmap image on its texture, and that isn't affected by the container's transform: The CALayer inside the UIImageView doesn't see that it's going to be (let's see..) 246x185 on-screen and re-scale its bitmap, it just lets OpenGL do its thing and scale down the bitmap every time it updates the display.
To get better scaling, we'll need to do it in CoreGraphics instead of OpenGL. Here's one way to do it:
- (UIImage*)scaleImage:(UIImage*)image by:(float)scale
{
CGSize size = CGSizeMake(image.size.width * scale, image.size.height * scale);
UIGraphicsBeginImageContextWithOptions(size, YES, 0.0);
[image drawInRect:CGRectMake(0, 0, size.width, size.height)];
UIImage *imageCopy = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return imageCopy;
}
- (void)loadView
{
// get landscape screen frame
CGRect screenFrame = [UIScreen mainScreen].bounds;
CGRect landscapeFrame = CGRectMake(0, 0, screenFrame.size.height, screenFrame.size.width);
UIView *view = [[UIView alloc] initWithFrame:landscapeFrame];
view.backgroundColor = [UIColor grayColor];
self.view = view;
// add container view for 2 images
CGRect startFrame = CGRectMake(-landscapeFrame.size.width/2, 0, landscapeFrame.size.width*2, landscapeFrame.size.height);
container = [[UIView alloc] initWithFrame:startFrame];
container.backgroundColor = [UIColor whiteColor];
// add image 1 (1024x768)
UIImage *img1 = [UIImage imageNamed:#"01.png"];
img1View = [[TapImageView alloc] initWithFrame:CGRectMake(0, 0, 1024, 768)];
img1View.userInteractionEnabled = YES; // important!
img1View.image = [self scaleImage:img1 by:0.24];
[container addSubview:img1View];
// add image 2 (1024x768)
UIImage *img2 = [UIImage imageNamed:#"02.png"];
img2View = [[TapImageView alloc] initWithFrame:CGRectMake(1024, 0, 1024, 768)];
img2View.userInteractionEnabled = YES;
img2View.image = [self scaleImage:img2 by:0.24];
[container addSubview:img2View];
// scale to 24% and layout subviews
zoomed = YES;
container.transform = CGAffineTransformMakeScale(0.24, 0.24);
[self.view addSubview:container];
}
- (void)viewTapped:(id)sender
{
zoomed = !zoomed;
[UIView animateWithDuration:0.5 animations:^
{
if ( zoomed )
{
container.transform = CGAffineTransformMakeScale(0.24, 0.24);
}
else
{
img1View.image = [UIImage imageNamed:#"01.png"];
img2View.image = [UIImage imageNamed:#"02.png"];
container.transform = CGAffineTransformMakeScale(1.0, 1.0);
}
}
completion:^(BOOL finished)
{
if ( zoomed )
{
UIImage *img1 = [UIImage imageNamed:#"01.png"];
img1View.image = [self scaleImage:img1 by:0.24];
UIImage *img2 = [UIImage imageNamed:#"02.png"];
img2View.image = [self scaleImage:img2 by:0.24];
}
}];
}
And here's TapImageView, a UIImageView subclass that tells us when it's been tapped by sending an action up the responder chain:
#interface TapImageView : UIImageView
#end
#implementation TapImageView
- (void)touchesEnded:(NSSet*)touches withEvent:(UIEvent*)event
{
[[UIApplication sharedApplication] sendAction:#selector(viewTapped:) to:nil from:self forEvent:event];
}
#end
Instead of scaling the container and all of its subviews. Create a UIImageView from the contents of the container and adjust its frame size to 24% of the original.
UIGraphicsBeginImageContext(container.bounds.size);
[container renderInContext:UIGraphicsGetCurrentContext()];
UIImage *containerImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageView *containerImageView = [[UIImageView alloc] initWithImage:containerImage];
CGRectFrame containerFrame = startFrame;
containerFrame.size.with *= 0.24;
containerFrame.size.height *= 0.24;
containerImageView.frame = containerFrame;
[self.view addSubView:containerImageView];
I wanna to make buttons for my app flat & transaparent, like the ones in the kindle app (see the shop button).
I try to set a custom background by code with not luck (the button is draw as a rectangle, with he border color fill all the background):
- (UIImage *) screenshot {
// Create a graphics context with the target size
// On iOS 4 and later, use UIGraphicsBeginImageContextWithOptions to take the scale into consideration
// On iOS prior to 4, fall back to use UIGraphicsBeginImageContext
CGSize imageSize = self.bounds.size;
if (NULL != UIGraphicsBeginImageContextWithOptions)
UIGraphicsBeginImageContextWithOptions(imageSize, NO, 0);
else
UIGraphicsBeginImageContext(imageSize);
CGContextRef context = UIGraphicsGetCurrentContext();
[self.layer renderInContext:context];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
+(UIImage *) buttonFlat {
UIView *bt = [[UIView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, 1.0f, 1.0f)];
bt.backgroundColor = [UIColor blackColor];
bt.layer.borderColor = [UIColor lightGrayColor].CGColor;
bt.layer.borderWidth = 1;
bt.layer.cornerRadius = 5.0;
bt.alpha = 0.7;
return [bt screenshot];
}
I know how do this with a normal UIButton, but prefer to make this so I can retain the standard icons of the UIBarButtonItem if possible...
A UIBarButton can hold any custom view:
UIBarButtonItem *barButton = [[UIBarButtonItem alloc] initWithCustomView:someView];
I am using QREncoder library found here: https://github.com/jverkoey/ObjQREncoder
Basically, i looked at the example code by this author, and when he creates the QRCode it comes out perfectly with no pixelation. The image itself that the library provides is 33 x 33 pixels, but he uses kCAFilterNearest to magnify and make it very clear (no pixilation). Here is his code:
UIImage* image = [QREncoder encode:#"http://www.google.com/"];
UIImageView* imageView = [[UIImageView alloc] initWithImage:image];
CGFloat qrSize = self.view.bounds.size.width - kPadding * 2;
imageView.frame = CGRectMake(kPadding, (self.view.bounds.size.height - qrSize) / 2,
qrSize, qrSize);
[imageView layer].magnificationFilter = kCAFilterNearest;
[self.view addSubview:imageView];
I have a UIImageView in a xib, and I am setting it's image like this:
[[template imageVQRCode] setImage:[QREncoder encode:ticketNum]];
[[[template imageVQRCode] layer] setMagnificationFilter:kCAFilterNearest];
but the qrcode is really blurry. In the example, it comes out crystal clear.
What am i doing wrong?
Thanks!
UPDATE:I found out that the problem isn't with scaling or anything to do with kCAFFilterNearest. It has to do with generating the PNG image from the view. Here's how it looks on the deive vs how it looks like when i save the UIView to the PNG representation (Notice the QRCodes quality):
UPDATE 2: This is how I am generating the PNG file from UIView:
UIGraphicsBeginImageContextWithOptions([[template view] bounds].size, YES, 0.0);
[[[template view] layer] renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
[UIImagePNGRepresentation(viewImage) writeToFile:plistPath atomically:YES];
I have used below function for editing image.
- (UIImage *)resizedImage:(CGSize)newSize interpolationQuality:(CGInterpolationQuality)quality
{
BOOL drawTransposed;
switch (self.imageOrientation) {
case UIImageOrientationLeft:
case UIImageOrientationLeftMirrored:
case UIImageOrientationRight:
case UIImageOrientationRightMirrored:
drawTransposed = YES;
break;
default:
drawTransposed = NO;
}
return [self resizedImage:newSize
transform:[self transformForOrientation:newSize]
drawTransposed:drawTransposed
interpolationQuality:quality];
}
- (UIImage *)resizedImage:(CGSize)newSize
transform:(CGAffineTransform)transform
drawTransposed:(BOOL)transpose
interpolationQuality:(CGInterpolationQuality)quality
{
CGRect newRect = CGRectIntegral(CGRectMake(0, 0, newSize.width, newSize.height));
CGRect transposedRect = CGRectMake(0, 0, newRect.size.height, newRect.size.width);
CGImageRef imageRef = self.CGImage;
// Build a context that's the same dimensions as the new size
CGBitmapInfo bitmapInfo = CGImageGetBitmapInfo(imageRef);
if((bitmapInfo == kCGImageAlphaLast) || (bitmapInfo == kCGImageAlphaNone))
bitmapInfo = kCGImageAlphaNoneSkipLast;
CGContextRef bitmap = CGBitmapContextCreate(NULL,
newRect.size.width,
newRect.size.height,
CGImageGetBitsPerComponent(imageRef),
0,
CGImageGetColorSpace(imageRef),
bitmapInfo);
// Rotate and/or flip the image if required by its orientation
CGContextConcatCTM(bitmap, transform);
// Set the quality level to use when rescaling
CGContextSetInterpolationQuality(bitmap, quality);
// Draw into the context; this scales the image
CGContextDrawImage(bitmap, transpose ? transposedRect : newRect, imageRef);
// Get the resized image from the context and a UIImage
CGImageRef newImageRef = CGBitmapContextCreateImage(bitmap);
UIImage *newImage = [UIImage imageWithCGImage:newImageRef];
// Clean up
CGContextRelease(bitmap);
CGImageRelease(newImageRef);
return newImage;
}
UIImageWriteToSavedPhotosAlbum([image resizedImage:CGSizeMake(300, 300) interpolationQuality:kCGInterpolationNone], nil, nil, nil);
Please find below image and let me know if you need any help.
I've been trying to display a NSImage on a CALayer. Then I realised I need to convert it to a CGImage apparently, then display it...
I have this code which doesn't seem to be working
CALayer *layer = [CALayer layer];
NSImage *finderIcon = [[NSWorkspace sharedWorkspace] iconForFileType:NSFileTypeForHFSTypeCode(kFinderIcon)];
[finderIcon setSize:(NSSize){ 128.0f, 128.0f }];
CGImageSourceRef source;
source = CGImageSourceCreateWithData((CFDataRef)finderIcon, NULL);
CGImageRef finalIcon = CGImageSourceCreateImageAtIndex(source, 0, NULL);
layer.bounds = CGRectMake(128.0f, 128.0f, 4, 4);
layer.position = CGPointMake(128.0f, 128.0f);
layer.contents = finalIcon;
// Insert the layer into the root layer
[mainLayer addSublayer:layer];
Why? How can I get this to work?
From the comments: Actually, if you're on 10.6, you can also just set the CALayer's contents to an NSImage rather than a CGImageRef...
If you're on OS X 10.6 or later, take a look at NSImage's CGImageForProposedRect:context:hints: method.
If you're not, I've got this in a category on NSImage:
-(CGImageRef)CGImage
{
CGContextRef bitmapCtx = CGBitmapContextCreate(NULL/*data - pass NULL to let CG allocate the memory*/,
[self size].width,
[self size].height,
8 /*bitsPerComponent*/,
0 /*bytesPerRow - CG will calculate it for you if it's allocating the data. This might get padded out a bit for better alignment*/,
[[NSColorSpace genericRGBColorSpace] CGColorSpace],
kCGBitmapByteOrder32Host|kCGImageAlphaPremultipliedFirst);
[NSGraphicsContext saveGraphicsState];
[NSGraphicsContext setCurrentContext:[NSGraphicsContext graphicsContextWithGraphicsPort:bitmapCtx flipped:NO]];
[self drawInRect:NSMakeRect(0,0, [self size].width, [self size].height) fromRect:NSZeroRect operation:NSCompositeCopy fraction:1.0];
[NSGraphicsContext restoreGraphicsState];
CGImageRef cgImage = CGBitmapContextCreateImage(bitmapCtx);
CGContextRelease(bitmapCtx);
return (CGImageRef)[(id)cgImage autorelease];
}
I think I wrote this myself. But it's entirely possible that I ripped it off from somewhere else like Stack Overflow. It's an older personal project and I don't really remember.
Here's some code which may help you - I sure hope the formatting of this does not get all messed up like it appears is going to happen - all I can offer is that this works for me.
// -------------------------------------------------------------------------------------
- (void)awakeFromNib
{
// setup our main window 'contentWindow' to use layers
[[contentWindow contentView] setWantsLayer:YES]; // NSWindow*
// create a root layer to contain all of our layers
CALayer *root = [[contentWindow contentView] layer];
// use constraint layout to allow sublayers to center themselves
root.layoutManager = [CAConstraintLayoutManager layoutManager];
// create a new layer which will contain ALL our sublayers
// -------------------------------------------------------
mContainer = [CALayer layer];
mContainer.bounds = root.bounds;
mContainer.frame = root.frame;
mContainer.position = CGPointMake(root.bounds.size.width * 0.5,
root.bounds.size.height * 0.5);
// insert layer on the bottom of the stack so it is behind the controls
[root insertSublayer:mContainer atIndex:0];
// make it resize when its superlayer does
root.autoresizingMask = kCALayerWidthSizable | kCALayerHeightSizable;
// make it resize when its superlayer does
mContainer.autoresizingMask = kCALayerWidthSizable | kCALayerHeightSizable;
}
// -------------------------------------------------------------------------------------
- (void) loadMyImage:(NSString*) path
n:(NSInteger) num
x:(NSInteger) xpos
y:(NSInteger) ypos
h:(NSInteger) hgt
w:(NSInteger) wid
b:(NSString*) blendstr
{
#ifdef __DEBUG_LOGGING__
NSLog(#"loadMyImage - ENTER [%#] num[%d] x[%d] y[%d] h[%d] w[%d] b[%#]",
path, num, xpos, ypos, hgt, wid, blendstr);
#endif
NSInteger xoffset = ((wid / 2) + xpos); // use CORNER versus CENTER for location
NSInteger yoffset = ((hgt / 2) + ypos);
CIFilter* filter = nil;
CGRect cgrect = CGRectMake((CGFloat) xoffset, (CGFloat) yoffset,
(CGFloat) wid, (CGFloat) hgt);
if(nil != blendstr) // would be equivalent to #"CIMultiplyBlendMode" or similar
{
filter = [CIFilter filterWithName:blendstr];
}
// read image file via supplied path
NSImage* theimage = [[NSImage alloc] initWithContentsOfFile:path];
if(nil != theimage)
{
[self setMyImageLayer:[CALayer layer]]; // create layer
myImageLayer.frame = cgrect; // locate & size image
myImageLayer.compositingFilter = filter; // nil is OK if no filter
[myImageLayer setContents:(id) theimage]; // deposit image into layer
// add new layer into our main layer [see awakeFromNib above]
[mContainer insertSublayer:myImageLayer atIndex:0];
[theimage release];
}
else
{
NSLog(#"ERROR loadMyImage - no such image [%#]", path);
}
}
+ (CGImageRef) getCachedImage:(NSString *) imageName
{
NSGraphicsContext *context = [[NSGraphicsContext currentContext] graphicsPort];
NSImage *img = [NSImage imageNamed:imageName];
NSRect rect = NSMakeRect(0, 0, [img size].width, [img size].height);
return [img CGImageForProposedRect:&rect context:context hints:NULL];
}
+ (CGImageRef) getImage:(NSString *) imageName withExtension:(NSString *) extension
{
NSGraphicsContext *context = [[NSGraphicsContext currentContext] graphicsPort];
NSString* imagePath = [[NSBundle mainBundle] pathForResource:imageName ofType:extension];
NSImage* img = [[NSImage alloc] initWithContentsOfFile:imagePath];
NSRect rect = NSMakeRect(0, 0, [img size].width, [img size].height);
CGImageRef imgRef = [img CGImageForProposedRect:&rect context:context hints:NULL];
[img release];
return imgRef;
}
then you can set it:
yourLayer.contents = (id)[self getCachedImage:#"myImage.png"];
or
yourLayer.contents = (id)[self getImage:#"myImage" withExtension:#"png"];