Merge pull request #10727 from electron/named-nativeimage

Add an API to get a nativeImage from a named NSImage

atom/common/api/atom_api_native_image.cc

@@ -541,6 +541,13 @@ mate::Handle<NativeImage> NativeImage::CreateFromDataURL(
   return CreateEmpty(isolate);
 }
 
+#if !defined(OS_MACOSX)
+mate::Handle<NativeImage> NativeImage::CreateFromNamedImage(
+  mate::Arguments* args, const std::string& name) {
+  return CreateEmpty(args->isolate());
+}
+#endif
+
 // static
 void NativeImage::BuildPrototype(
     v8::Isolate* isolate, v8::Local<v8::FunctionTemplate> prototype) {
@@ -609,6 +616,8 @@ void Initialize(v8::Local<v8::Object> exports, v8::Local<v8::Value> unused,
   dict.SetMethod("createFromBuffer", &atom::api::NativeImage::CreateFromBuffer);
   dict.SetMethod("createFromDataURL",
                  &atom::api::NativeImage::CreateFromDataURL);
+  dict.SetMethod("createFromNamedImage",
+                 &atom::api::NativeImage::CreateFromNamedImage);
 }
 
 }  // namespace

atom/common/api/atom_api_native_image.h

@@ -53,6 +53,8 @@ class NativeImage : public mate::Wrappable<NativeImage> {
       mate::Arguments* args, v8::Local<v8::Value> buffer);
   static mate::Handle<NativeImage> CreateFromDataURL(
       v8::Isolate* isolate, const GURL& url);
+  static mate::Handle<NativeImage> CreateFromNamedImage(
+      mate::Arguments* args, const std::string& name);
 
   static void BuildPrototype(v8::Isolate* isolate,
                              v8::Local<v8::FunctionTemplate> prototype);

atom/common/api/atom_api_native_image_mac.mm

@@ -6,10 +6,56 @@
 
 #import <Cocoa/Cocoa.h>
 
+#include "base/strings/sys_string_conversions.h"
+#include "ui/gfx/color_utils.h"
+#include "ui/gfx/image/image.h"
+#include "ui/gfx/image/image_skia.h"
+#include "ui/gfx/image/image_skia_operations.h"
+
 namespace atom {
 
 namespace api {
 
+NSData* bufferFromNSImage(NSImage* image) {
+  CGImageRef ref = [image CGImageForProposedRect:nil context:nil hints:nil];
+  NSBitmapImageRep* rep = [[NSBitmapImageRep alloc] initWithCGImage:ref];
+  [rep setSize:[image size]];
+  return [rep representationUsingType:NSPNGFileType properties:[[NSDictionary alloc] init]];
+}
+
+double safeShift(double in, double def) {
+  if (in >= 0 || in <= 1 || in == def) return in;
+  return def;
+}
+
+mate::Handle<NativeImage> NativeImage::CreateFromNamedImage(
+  mate::Arguments* args, const std::string& name) {
+  @autoreleasepool {
+    std::vector<double> hsl_shift;
+    NSImage* image = [NSImage imageNamed:base::SysUTF8ToNSString(name)];
+    if (!image.valid) {
+      return CreateEmpty(args->isolate());
+    }
+
+    NSData* png_data = bufferFromNSImage(image);
+
+    if (args->GetNext(&hsl_shift) && hsl_shift.size() == 3) {
+      gfx::Image gfx_image = gfx::Image::CreateFrom1xPNGBytes(
+        reinterpret_cast<const unsigned char*>((char *) [png_data bytes]), [png_data length]);
+      color_utils::HSL shift = {
+        safeShift(hsl_shift[0], -1),
+        safeShift(hsl_shift[1], 0.5),
+        safeShift(hsl_shift[2], 0.5)
+      };
+      png_data = bufferFromNSImage(gfx::Image(
+        gfx::ImageSkiaOperations::CreateHSLShiftedImage(
+          gfx_image.AsImageSkia(), shift)).CopyNSImage());
+    }
+
+    return CreateFromPNG(args->isolate(), (char *) [png_data bytes], [png_data length]);
+  }
+}
+
 void NativeImage::SetTemplateImage(bool setAsTemplate) {
   [image_.AsNSImage() setTemplate:setAsTemplate];
 }

docs/api/native-image.md

@@ -157,6 +157,34 @@ Returns `NativeImage`
 
 Creates a new `NativeImage` instance from `dataURL`.
 
+### `nativeImage.createFromNamedImage(imageName[, hslShift])` _macOS_
+
+* `imageName` String
+* `hslShift` Number[]
+
+Returns `NativeImage`
+
+Creates a new `NativeImage` instance from the NSImage that maps to the
+given image name.  See [`NSImageName`](https://developer.apple.com/documentation/appkit/nsimagename?language=objc)
+for a list of possible values.
+
+The `hslShift` is applied to the image with the following rules
+* `hsl_shift[0]` (hue): The absolute hue value for the image - 0 and 1 map
+     to 0 and 360 on the hue color wheel (red).
+* `hsl_shift[1]` (saturation): A saturation shift for the image, with the
+    following key values:  
+    0 = remove all color.  
+    0.5 = leave unchanged.  
+    1 = fully saturate the image.  
+* `hsl_shift[2]` (lightness): A lightness shift for the image, with the
+    following key values:  
+    0 = remove all lightness (make all pixels black).  
+    0.5 = leave unchanged.  
+    1 = full lightness (make all pixels white).
+
+This means that `[-1, 0, 1]` will make the image completely white and
+`[-1, 1, 0]` will make the image completely black.
+
 ## Class: NativeImage
 
 > Natively wrap images such as tray, dock, and application icons.

spec/api-native-image-spec.js

@@ -190,6 +190,34 @@ describe('nativeImage module', () => {
     })
   })
 
+  describe('createFromNamedImage(name)', () => {
+    it('returns empty for invalid options', () => {
+      const image = nativeImage.createFromNamedImage('totally_not_real')
+      assert(image.isEmpty())
+    })
+
+    it('returns empty on non-darwin platforms', () => {
+      if (process.platform === 'darwin') return
+
+      const image = nativeImage.createFromNamedImage('NSActionTemplate')
+      assert(image.isEmpty())
+    })
+
+    it('returns a valid image on darwin', () => {
+      if (process.platform !== 'darwin') return
+
+      const image = nativeImage.createFromNamedImage('NSActionTemplate')
+      assert(!image.isEmpty())
+    })
+
+    it('returns allows an HSL shift for a valid image on darwin', () => {
+      if (process.platform !== 'darwin') return
+
+      const image = nativeImage.createFromNamedImage('NSActionTemplate', [0.5, 0.2, 0.8])
+      assert(!image.isEmpty())
+    })
+  })
+
   describe('resize(options)', () => {
     it('returns a resized image', () => {
       const image = nativeImage.createFromPath(path.join(__dirname, 'fixtures', 'assets', 'logo.png'))