[ios, macos] Add attribution to snapshots.

1 files changed, 117 insertions, 2 deletions

diff --git a/platform/darwin/src/MGLMapSnapshotter.mm b/platform/darwin/src/MGLMapSnapshotter.mm
index a00521a87a..be76a30511 100644
--- a/platform/darwin/src/MGLMapSnapshotter.mm
+++ b/platform/darwin/src/MGLMapSnapshotter.mm
@@ -14,11 +14,14 @@
 #import "MGLGeometry_Private.h"
 #import "NSBundle+MGLAdditions.h"
 #import "MGLStyle.h"
+#import "MGLAttributionInfo_Private.h"
 
 #if TARGET_OS_IPHONE
 #import "UIImage+MGLAdditions.h"
 #else
 #import "NSImage+MGLAdditions.h"
+#import <CoreGraphics/CoreGraphics.h>
+#import <QuartzCore/QuartzCore.h>
 #endif
 
 const CGPoint MGLLogoImagePosition = CGPointMake(8, 8);
@@ -146,6 +149,33 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64;
     dispatch_async(queue, ^{
         _snapshotCallback = std::make_unique<mbgl::Actor<mbgl::MapSnapshotter::Callback>>(*mbgl::Scheduler::GetCurrent(), [=](std::exception_ptr mbglError, mbgl::PremultipliedImage image, mbgl::MapSnapshotter::Attributions attributions, mbgl::MapSnapshotter::PointForFn pointForFn) {
             _loading = false;
+            
+            NSMutableArray *infos = [NSMutableArray array];
+
+#if TARGET_OS_IPHONE
+            CGFloat fontSize = [UIFont smallSystemFontSize];
+            UIColor *attributeFontColor = [UIColor blackColor];
+#else
+            CGFloat fontSize = [NSFont systemFontSizeForControlSize:NSMiniControlSize];
+            NSColor *attributeFontColor = [NSColor blackColor];
+#endif
+            for (auto attribution = attributions.begin(); attribution != attributions.end(); ++attribution) {
+                NSString *attributionHTMLString = @(attribution->c_str());
+                NSArray *tileSetInfos = [MGLAttributionInfo attributionInfosFromHTMLString:attributionHTMLString
+                                                                                  fontSize:fontSize
+                                                                                 linkColor:attributeFontColor];
+                [infos growArrayByAddingAttributionInfosFromArray:tileSetInfos];
+            }
+            
+            CGSize attributionBackgroundSize = CGSizeMake(10, 0);
+            for (MGLAttributionInfo *info in infos) {
+                if (info.isFeedbackLink) {
+                    continue;
+                }
+                attributionBackgroundSize.width += [info.title size].width + 10;
+                attributionBackgroundSize.height = MAX([info.title size].height, attributionBackgroundSize.height);
+            }
+            
             if (mbglError) {
                 NSString *description = @(mbgl::util::toString(mbglError).c_str());
                 NSDictionary *userInfo = @{NSLocalizedDescriptionKey: description};
@@ -170,10 +200,33 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64;
 #if TARGET_OS_IPHONE
                     UIImage *logoImage = [UIImage imageNamed:@"mapbox" inBundle:[NSBundle mgl_frameworkBundle] compatibleWithTraitCollection:nil];
                     
+                    CGRect logoImageRect = CGRectMake(MGLLogoImagePosition.x, mglImage.size.height - (MGLLogoImagePosition.y + logoImage.size.height), logoImage.size.width, logoImage.size.height);
+                    
+                    CGPoint attributionTextPosition = CGPointMake(mglImage.size.width - 10 - attributionBackgroundSize.width,
+                                                                  logoImageRect.origin.y + (logoImageRect.size.height / 2) - (attributionBackgroundSize.height / 2));
+                    
+                    CGRect cropRect = CGRectMake(attributionTextPosition.x * mglImage.scale, (attributionTextPosition.y + 1)  * mglImage.scale, attributionBackgroundSize.width  * mglImage.scale, attributionBackgroundSize.height  * mglImage.scale);
+                    
+                    
                     UIGraphicsBeginImageContextWithOptions(mglImage.size, NO, self.options.scale);
                     
                     [mglImage drawInRect:CGRectMake(0, 0, mglImage.size.width, mglImage.size.height)];
-                    [logoImage drawInRect:CGRectMake(MGLLogoImagePosition.x, mglImage.size.height - (MGLLogoImagePosition.y + logoImage.size.height), logoImage.size.width,logoImage.size.height)];
+                    
+                    [logoImage drawInRect:logoImageRect];
+                    
+                    UIImage *currentImage = UIGraphicsGetImageFromCurrentImageContext();
+                    CGImageRef attributionImageRef = CGImageCreateWithImageInRect([currentImage CGImage], cropRect);
+                    UIImage *attributionImage = [UIImage imageWithCGImage:attributionImageRef];
+                    CGImageRelease(attributionImageRef);
+                    
+                    CIImage *ciAttributionImage = [[CIImage alloc] initWithCGImage:attributionImage.CGImage];
+                    
+                    UIImage *blurredAttributionBackground = [self blurredAttributionBackground:ciAttributionImage];
+                    
+                    [blurredAttributionBackground drawInRect:CGRectMake(attributionTextPosition.x, attributionTextPosition.y + 1, attributionBackgroundSize.width, attributionBackgroundSize.height)];
+                    
+                    [self drawAttributionText:infos origin:CGPointMake(attributionTextPosition.x + 10, attributionTextPosition.y)];
+                    
                     UIImage *compositedImage = UIGraphicsGetImageFromCurrentImageContext();
                     
                     UIGraphicsEndImageContext();
@@ -183,6 +236,11 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64;
                     
                     NSSize targetSize = NSMakeSize(self.options.size.width, self.options.size.height);
                     NSRect targetFrame = NSMakeRect(0, 0, targetSize.width, targetSize.height);
+                    CGRect logoImageRect = CGRectMake(MGLLogoImagePosition.x, MGLLogoImagePosition.y, logoImage.size.width, logoImage.size.height);
+                    CGPoint attributionTextPosition = CGPointMake(targetFrame.size.width - 10 - attributionBackgroundSize.width,
+                                                                  logoImageRect.origin.y + (logoImageRect.size.height / 2) - (attributionBackgroundSize.height / 2));
+                    
+                    
                     NSImage *compositedImage = nil;
                     NSImageRep *sourceImageRep = [sourceImage bestRepresentationForRect:targetFrame
                                                                                 context:nil
@@ -190,10 +248,26 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64;
                     compositedImage = [[NSImage alloc] initWithSize:targetSize];
                     
                     [compositedImage lockFocus];
+
                     [sourceImageRep drawInRect: targetFrame];
-                    [logoImage drawInRect:CGRectMake(MGLLogoImagePosition.x, MGLLogoImagePosition.y, logoImage.size.width,logoImage.size.height)];
+                    
+                    [logoImage drawInRect:logoImageRect];
+                    
+                    NSRect cropRect = NSMakeRect(attributionTextPosition.x, MGLLogoImagePosition.y + 1, attributionBackgroundSize.width, attributionBackgroundSize.height);
+                    
+                    NSBitmapImageRep *attributionBackground = [[NSBitmapImageRep alloc] initWithFocusedViewRect: cropRect];
+                    
+                    CIImage *attributionBackgroundImage = [[CIImage alloc] initWithCGImage:[attributionBackground CGImage]];
+                    
+                    NSImage *blurredAttributionBackground = [self blurredAttributionBackground:attributionBackgroundImage];
+
+                    [blurredAttributionBackground drawInRect:CGRectMake(attributionTextPosition.x, MGLLogoImagePosition.y + 1, attributionBackgroundSize.width, attributionBackgroundSize.height)];
+                    
+                    [self drawAttributionText:infos origin:CGPointMake(attributionTextPosition.x + 10, attributionTextPosition.y)];
+                    
                     [compositedImage unlockFocus];
                     
+                    
 #endif
                     
                     // Dispatch result to origin queue
@@ -208,6 +282,47 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64;
     });
 }
 
+- (void)drawAttributionText:(NSArray *)attributionInfo origin:(CGPoint)origin
+{
+    for (MGLAttributionInfo *info in attributionInfo) {
+        if (info.isFeedbackLink) {
+            continue;
+        }
+        [info.title drawAtPoint:origin];
+        
+        origin.x += [info.title size].width + 10;
+    }
+}
+
+- (MGLImage *)blurredAttributionBackground:(CIImage *)backgroundImage
+{
+    CGAffineTransform transform = CGAffineTransformIdentity;
+    CIFilter *clamp = [CIFilter filterWithName:@"CIAffineClamp"];
+    [clamp setValue:backgroundImage forKey:kCIInputImageKey];
+    [clamp setValue:[NSValue valueWithBytes:&transform objCType:@encode(CGAffineTransform)] forKey:@"inputTransform"];
+    
+    CIFilter *attributionBlurFilter = [CIFilter filterWithName:@"CIGaussianBlur"];
+    [attributionBlurFilter setValue:[clamp outputImage] forKey:kCIInputImageKey];
+    [attributionBlurFilter setValue:@10 forKey:kCIInputRadiusKey];
+    
+    CIFilter *attributionColorFilter = [CIFilter filterWithName:@"CIColorControls"];
+    [attributionColorFilter setValue:[attributionBlurFilter outputImage] forKey:kCIInputImageKey];
+    [attributionColorFilter setValue:@(0.1) forKey:kCIInputBrightnessKey];
+    
+    CIImage *blurredImage = attributionColorFilter.outputImage;
+    
+    CIContext *ctx = [CIContext contextWithOptions:nil];
+    CGImageRef cgimg = [ctx createCGImage:blurredImage fromRect:[backgroundImage extent]];
+    
+#if TARGET_OS_IPHONE
+    
+    return [UIImage imageWithCGImage:cgimg];
+#else
+    
+    return [[NSImage alloc] initWithCGImage:cgimg size:[backgroundImage extent].size];
+#endif
+}
+
 - (void)cancel
 {
     _snapshotCallback.reset();