1 //

     2 //  UIImageExtra.m

     3 //  HedgewarsMobile

     4 //

     5 //  Created by Vittorio on 08/04/10.

     6 //  Copyright 2010 __MyCompanyName__. All rights reserved.

     7 //

     8 

     9 #import "UIImageExtra.h"

    10 

    11 

    12 @implementation UIImage (extra)

    13  

    14 -(UIImage *)scaleToSize:(CGSize) size {

    15   // Create a bitmap graphics context

    16   // This will also set it as the current context

    17   UIGraphicsBeginImageContext(size);

    18  

    19   // Draw the scaled image in the current context

    20   [self drawInRect:CGRectMake(0, 0, size.width, size.height)];

    21  

    22   // Create a new image from current context

    23   UIImage* scaledImage = UIGraphicsGetImageFromCurrentImageContext();

    24  

    25   // Pop the current context from the stack

    26   UIGraphicsEndImageContext();

    27  

    28   // Return our new scaled image (autoreleased)

    29   return scaledImage;

    30 }

    31 

    32 -(UIImage *)mergeWith:(UIImage *)secondImage atPoint:(CGPoint) secondImagePoint {

    33     // create a contex of size of the background image

    34     return [self mergeWith:secondImage atPoint:secondImagePoint atSize:self.size];

    35 }

    36 

    37 -(UIImage *)mergeWith:(UIImage *)secondImage atPoint:(CGPoint) secondImagePoint atSize:(CGSize) resultingSize {

    38     UIGraphicsBeginImageContext(resultingSize);

    39     

    40     // drav the background image

    41     [self drawAtPoint:CGPointMake(0,0)];

    42     

    43     // draw the image on top of the first image

    44     [secondImage drawAtPoint:secondImagePoint];

    45     

    46     // create an image from the current contex (not thread safe)

    47     UIImage *resultImage = UIGraphicsGetImageFromCurrentImageContext();

    48     

    49     // free drawing contex

    50     UIGraphicsEndImageContext();

    51     

    52     // return the resulting autoreleased image

    53     return resultImage;

    54 }

    55 

    56 -(id) initWithContentsOfFile:(NSString *)path andCutAt:(CGRect) rect {

    57     // load image from path

    58     UIImage *image = [[UIImage alloc] initWithContentsOfFile: path];

    59     

    60     if (nil != image) {

    61         // get its CGImage representation with a give size

    62         CGImageRef cgImgage = CGImageCreateWithImageInRect([image CGImage], rect);

    63     

    64         // clean memory

    65         [image release];

    66     

    67         // create a UIImage from the CGImage (memory must be allocated already)

    68         UIImage *sprite = [self initWithCGImage:cgImgage];

    69     

    70         // clean memory

    71         CGImageRelease(cgImgage);

    72 

    73         // return resulting image

    74         return sprite;

    75     } else {

    76         DLog(@"error - image == nil");

    77         return nil;

    78     }

    79 }

    80 

    81 -(UIImage *)convertToGrayScale {

    82   // Create image rectangle with current image width/height

    83   CGRect imageRect = CGRectMake(0, 0, self.size.width, self.size.height);

    84  

    85   // Grayscale color space

    86   CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceGray();

    87  

    88   // Create bitmap content with current image size and grayscale colorspace

    89   CGContextRef context = CGBitmapContextCreate(nil, self.size.width, self.size.height, 8, 0, colorSpace, kCGImageAlphaNone);

    90  

    91   // Draw image into current context, with specified rectangle

    92   // using previously defined context (with grayscale colorspace)

    93   CGContextDrawImage(context, imageRect, [self CGImage]);

    94  

    95   // Create bitmap image info from pixel data in current context

    96   CGImageRef imageRef = CGBitmapContextCreateImage(context);

    97  

    98   // Create a new UIImage object  

    99   UIImage *newImage = [UIImage imageWithCGImage:imageRef];

   100  

   101   // Release colorspace, context and bitmap information

   102   CGColorSpaceRelease(colorSpace);

   103   CGContextRelease(context);

   104   CFRelease(imageRef);

   105  

   106   // Return the new grayscale image

   107   return newImage;

   108 }

   109 

   110 // by http://iphonedevelopertips.com/cocoa/how-to-mask-an-image.html turned into a category by koda

   111 -(UIImage*) maskImageWith:(UIImage *)maskImage {

   112     CGImageRef maskRef = maskImage.CGImage;

   113     

   114     CGImageRef mask = CGImageMaskCreate(CGImageGetWidth(maskRef),

   115                                         CGImageGetHeight(maskRef),

   116                                         CGImageGetBitsPerComponent(maskRef),

   117                                         CGImageGetBitsPerPixel(maskRef),

   118                                         CGImageGetBytesPerRow(maskRef),

   119                                         CGImageGetDataProvider(maskRef), NULL, false);

   120     

   121     CGImageRef masked = CGImageCreateWithMask([self CGImage], mask);

   122     

   123     CGImageRelease(mask);

   124     

   125     UIImage* retImage = [UIImage imageWithCGImage:masked];

   126     

   127     CGImageRelease(masked);

   128     

   129     return retImage;

   130 }

   131 

   132 // by http://blog.sallarp.com/iphone-uiimage-round-corners/ turned into a category by koda

   133 void addRoundedRectToPath(CGContextRef context, CGRect rect, float ovalWidth, float ovalHeight)

   134 {

   135     float fw, fh;

   136     if (ovalWidth == 0 || ovalHeight == 0) {

   137         CGContextAddRect(context, rect);

   138         return;

   139     }

   140     CGContextSaveGState(context);

   141     CGContextTranslateCTM (context, CGRectGetMinX(rect), CGRectGetMinY(rect));

   142     CGContextScaleCTM (context, ovalWidth, ovalHeight);

   143     fw = CGRectGetWidth (rect) / ovalWidth;

   144     fh = CGRectGetHeight (rect) / ovalHeight;

   145     CGContextMoveToPoint(context, fw, fh/2);

   146     CGContextAddArcToPoint(context, fw, fh, fw/2, fh, 1);

   147     CGContextAddArcToPoint(context, 0, fh, 0, fh/2, 1);

   148     CGContextAddArcToPoint(context, 0, 0, fw/2, 0, 1);

   149     CGContextAddArcToPoint(context, fw, 0, fw, fh/2, 1);

   150     CGContextClosePath(context);

   151     CGContextRestoreGState(context);

   152 }

   153 

   154 -(UIImage *)makeRoundCornersOfSize:(CGSize) sizewh {

   155 	UIImage * newImage = nil;

   156     

   157     NSInteger cornerWidth = sizewh.width;

   158     NSInteger cornerHeight = sizewh.height;

   159     int w = self.size.width;

   160     int h = self.size.height;

   161     

   162     CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();

   163     CGContextRef context = CGBitmapContextCreate(NULL, w, h, 8, 4 * w, colorSpace, kCGImageAlphaPremultipliedFirst);

   164     

   165     CGContextBeginPath(context);

   166     CGRect rect = CGRectMake(0, 0, w, h);

   167     addRoundedRectToPath(context, rect, cornerWidth, cornerHeight);

   168     CGContextClosePath(context);

   169     CGContextClip(context);

   170     

   171     CGContextDrawImage(context, CGRectMake(0, 0, w, h), self.CGImage);

   172     

   173     CGImageRef imageMasked = CGBitmapContextCreateImage(context);

   174     CGContextRelease(context);

   175     CGColorSpaceRelease(colorSpace);

   176     

   177     newImage = [UIImage imageWithCGImage:imageMasked];

   178     CGImageRelease(imageMasked);

   179         

   180     return newImage;

   181 }

   182 

   183 

   184 @end