drawImage with HighQuality is anything but



When using drawImage to render a downscaled icon (from 160px to 56px), the quality setting doesn’t really matter. It looks like the image is always rendered with nearest neighbor.

As you can see (especially when zooming in) the JUCE lowQuality is pretty much equivalent to Photoshops nearest neighbor setting. Which makes sense. It’s supposed to be low-quality and cheap.

But even when setting the quality to “highest”, it’s not much better. I’ve attached examples for Photoshops bilinear and bicubic and the difference in quality is staggering. The zoomed in versions are already the highest quality for JUCE on the left, and Photoshop bilinear and bicubic zoomed in 200%.

JUCE claims to use area-averaging for down-sampling, but the results like straight up like nearest neighbor to me.

Is this a bug or is this expected?