1 files changed, 121 insertions, 0 deletions
diff --git a/platform/darwin/src/image.mm b/platform/darwin/src/image.mm
new file mode 100644
index 0000000000..854b9157f8
--- /dev/null
+++ b/platform/darwin/src/image.mm
@@ -0,0 +1,121 @@
+#include <mbgl/util/image.hpp>
+
+#import <ImageIO/ImageIO.h>
+
+#if TARGET_OS_IPHONE
+#import <MobileCoreServices/MobileCoreServices.h>
+#else
+#import <CoreServices/CoreServices.h>
+#endif
+
+namespace mbgl {
+
+std::string encodePNG(const PremultipliedImage& src) {
+    CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, src.data.get(), src.size(), NULL);
+    if (!provider) {
+        return "";
+    }
+
+    CGColorSpaceRef color_space = CGColorSpaceCreateDeviceRGB();
+    if (!color_space) {
+        CGDataProviderRelease(provider);
+        return "";
+    }
+
+    CGImageRef image = CGImageCreate(src.width, src.height, 8, 32, 4 * src.width, color_space,
+        kCGBitmapByteOrderDefault | kCGImageAlphaPremultipliedLast, provider, NULL, false,
+        kCGRenderingIntentDefault);
+    if (!image) {
+        CGColorSpaceRelease(color_space);
+        CGDataProviderRelease(provider);
+        return "";
+    }
+
+    CFMutableDataRef data = CFDataCreateMutable(kCFAllocatorDefault, 0);
+    if (!data) {
+        CGImageRelease(image);
+        CGColorSpaceRelease(color_space);
+        CGDataProviderRelease(provider);
+        return "";
+    }
+
+    CGImageDestinationRef image_destination = CGImageDestinationCreateWithData(data, kUTTypePNG, 1, NULL);
+    if (!image_destination) {
+        CFRelease(data);
+        CGImageRelease(image);
+        CGColorSpaceRelease(color_space);
+        CGDataProviderRelease(provider);
+        return "";
+    }
+
+    CGImageDestinationAddImage(image_destination, image, NULL);
+    CGImageDestinationFinalize(image_destination);
+
+    const std::string result {
+        reinterpret_cast<const char *>(CFDataGetBytePtr(data)),
+        static_cast<size_t>(CFDataGetLength(data))
+    };
+
+    CFRelease(image_destination);
+    CFRelease(data);
+    CGImageRelease(image);
+    CGColorSpaceRelease(color_space);
+    CGDataProviderRelease(provider);
+
+    return result;
+}
+
+PremultipliedImage decodeImage(const std::string &source_data) {
+    CFDataRef data = CFDataCreateWithBytesNoCopy(kCFAllocatorDefault, reinterpret_cast<const unsigned char *>(source_data.data()), source_data.size(), kCFAllocatorNull);
+    if (!data) {
+        throw std::runtime_error("CFDataCreateWithBytesNoCopy failed");
+    }
+
+    CGImageSourceRef image_source = CGImageSourceCreateWithData(data, NULL);
+    if (!image_source) {
+        CFRelease(data);
+        throw std::runtime_error("CGImageSourceCreateWithData failed");
+    }
+
+    CGImageRef image = CGImageSourceCreateImageAtIndex(image_source, 0, NULL);
+    if (!image) {
+        CFRelease(image_source);
+        CFRelease(data);
+        throw std::runtime_error("CGImageSourceCreateImageAtIndex failed");
+    }
+
+    CGColorSpaceRef color_space = CGColorSpaceCreateDeviceRGB();
+    if (!color_space) {
+        CGImageRelease(image);
+        CFRelease(image_source);
+        CFRelease(data);
+        throw std::runtime_error("CGColorSpaceCreateDeviceRGB failed");
+    }
+
+    PremultipliedImage result { CGImageGetWidth(image), CGImageGetHeight(image) };
+
+    CGContextRef context = CGBitmapContextCreate(result.data.get(), result.width, result.height, 8, result.stride(),
+        color_space, kCGImageAlphaPremultipliedLast);
+    if (!context) {
+        CGColorSpaceRelease(color_space);
+        CGImageRelease(image);
+        CFRelease(image_source);
+        CFRelease(data);
+        throw std::runtime_error("CGBitmapContextCreate failed");
+    }
+
+    CGContextSetBlendMode(context, kCGBlendModeCopy);
+
+    CGRect rect = {{ 0, 0 }, { static_cast<CGFloat>(result.width), static_cast<CGFloat>(result.height) }};
+    CGContextDrawImage(context, rect, image);
+
+    CGContextRelease(context);
+    CGColorSpaceRelease(color_space);
+    CGImageRelease(image);
+    CFRelease(image_source);
+    CFRelease(data);
+
+    return result;
+}
+
+}