LiveCode Forums.

A couple of years ago I wrote a LC app -- intended solely for macOS and Windows -- that models a classic neuropsychological test. It displays a series of approximately 330 images, to each of which the respondent must answer (via keyboard) with a number between 1 and 4. It works just fine.

Here's the thing: Having been vaguely mindful of upcoming HD displays (e.g., Retina), I employed 300-ppi PNG images -- knowing, of course, that this was overkill for a non-HD display and would bloat the size of the standalone, but hoping that this might avoid pixelation on a HD display.

Still concerned, I've redrawn several of those images as SVGs and created a macOS standalone to do an A-B comparison between the PNG and SVG versions. (BTW, LC 9.5.1 has worked just fine in displaying my SVG graphics when the XML is pasted as text into the image object.)

For this app, the size of each graphic is fixed -- irrespective of the dimensions of the screen -- so resizing graphics is not an issue.

On my non-Retina iMac, the PNGs and SVGs are essentially indistinguishable (apart from the basic blue-green-red colors being a bit brighter).

A friend who does have a Retina MacBook also found that these were indistinguishable when running the standalone.

So here's the question: Is it worth (at least for now) redrawing all 330+ PNG graphics as SVGs even for HD displays? (Redrawing would require at least a few hundred hours and might delay the publication of my app by nearly a year.)

I understand that the situation may be different with respect to the application icons and perhaps with designing for iOS.

I welcome your experience in handling graphics in light of "Retina" and other HD displays.

jeff k

@jmk_phd: If you are already including the 300ppi images in your standalone then you shouldn't have to do anything.

When we added retina support we made sure that the engine will use as many source pixels as it can from images. So if you have a 600x600px image rendered into a 300x300px square, on a non-retina machine the engine will downscale the image, but on a retina (2 device pixels to 1 logical pixel) the engine will keep the image as is - i.e. it will use all the pixels in the image.

Thanks much for the clarification.

According to the Wikipedia entry for "Retina display," all desktop/laptop Macs to date employ a pixel density well under 300ppi, so -- as you've indicated -- my 300ppi images should render just fine for the foreseeable future. (I suppose that the issue would be of concern only if/when I were to develop a standalone for the iPad mini.) I assume that the same will hold true for a Windows standalone.

You've saved me both the worry and hassle of having to fast-track recreating my raster images as SVGs, although it is reassuring to know that the few images I did redraw as SVGs have worked just fine in LC 9.5.1.

Best,

jeff k