diff --git a/src/video/cocoa/SDL_cocoamodes.m b/src/video/cocoa/SDL_cocoamodes.m index a2d72804c..ad8bfa290 100644 --- a/src/video/cocoa/SDL_cocoamodes.m +++ b/src/video/cocoa/SDL_cocoamodes.m @@ -443,27 +443,41 @@ Cocoa_GetDisplayUsableBounds(_THIS, SDL_VideoDisplay * display, SDL_Rect * rect) int Cocoa_GetDisplayDPI(_THIS, SDL_VideoDisplay * display, float * ddpi, float * hdpi, float * vdpi) +{ @autoreleasepool { const float MM_IN_INCH = 25.4f; SDL_DisplayData *data = (SDL_DisplayData *) display->driverdata; - CGSize displaySize = CGDisplayScreenSize(data->display); - int pixelWidth = (int) CGDisplayPixelsWide(data->display); - int pixelHeight = (int) CGDisplayPixelsHigh(data->display); + /* we need the backingScaleFactor for Retina displays, which is only exposed through NSScreen, not CGDisplay, afaik, so find our screen... */ + CGFloat scaleFactor = 1.0f; + NSArray *screens = [NSScreen screens]; + for (NSScreen *screen in screens) { + const CGDirectDisplayID dpyid = (const CGDirectDisplayID ) [[[screen deviceDescription] objectForKey:@"NSScreenNumber"] unsignedIntValue]; + if (dpyid == data->display) { + if ([screen respondsToSelector:@selector(backingScaleFactor)]) { // Mac OS X 10.7 and later + scaleFactor = [screen backingScaleFactor]; + break; + } + } + } + + const CGSize displaySize = CGDisplayScreenSize(data->display); + const int pixelWidth = (int) CGDisplayPixelsWide(data->display); + const int pixelHeight = (int) CGDisplayPixelsHigh(data->display); if (ddpi) { - *ddpi = SDL_ComputeDiagonalDPI(pixelWidth, pixelHeight, displaySize.width / MM_IN_INCH, displaySize.height / MM_IN_INCH); + *ddpi = (SDL_ComputeDiagonalDPI(pixelWidth, pixelHeight, displaySize.width / MM_IN_INCH, displaySize.height / MM_IN_INCH)) * scaleFactor; } if (hdpi) { - *hdpi = pixelWidth * MM_IN_INCH / displaySize.width; + *hdpi = (pixelWidth * MM_IN_INCH / displaySize.width) * scaleFactor; } if (vdpi) { - *vdpi = pixelHeight * MM_IN_INCH / displaySize.height; + *vdpi = (pixelHeight * MM_IN_INCH / displaySize.height) * scaleFactor; } return 0; -} +}} void Cocoa_GetDisplayModes(_THIS, SDL_VideoDisplay * display)