Font smoothing

[Martin Wynne]

I like to have font-smoothing switched on. It doesn't seem to affect
performance unduly and I find on-screen text much more comfortable
to read. It also makes screenshots look a lot neater.

But for some reason it's not working in Impict's text objects and
callouts (see attached shots). As a result they look a bit scruffy
alongside smoothed text in some of my screenshots.

Yes, this is TrueType Arial, it's not a bitmap font in the callouts.

Is there a setting somewhere controlling this? Or is it one for the
wish list?

regards,

Martin.

[Tim Green]

Martin,

Select the callout object, then select Object > Anti-Aliasing.... (The text in the callout objects aren't "covered" by Windows' font smoothing.)

[Martin Wynne]

Martin,

Select the object, then select Object > Anti-Aliasing...

Thanks, Tim.

But that's not quite the same thing. Windows font smoothing applies
only to the curved parts of each TrueType character. Straight sections
remain crisp.

Anti-aliasing affects all parts of a character, with the result that it looks
smudged.

A couple of shots attached.

Am I being too fussy?

Martin.

[Tim Green]

I know it's not the same thing but that's what's available (screenshots aren't necessary...). However, since Windows font smoothing is not applied to objects like these we have to make do with anti-aliasing.

I generally find that fonts in these objects look better if you don't use anti-aliasing on them at all. (If you want to use fonts at the magnification shown in your screenshots you should probably be using PhotoShop or PaintShop Pro to make them as graphical objects anyway, that would produce much better results.) One trick I sometimes use is to create a callout without any text, then I can antialias its outline. Then I create a text object with crisp, non antialiased text and position it over the callout.

[Martin Wynne]

I know it's not the same thing but that's what's available (screenshots aren't necessary...). However, since Windows font smoothing is not applied to objects like these we have to make do with anti-aliasing.

I generally find that fonts in these objects look better if you don't use anti-aliasing on them at all. (If you want to use fonts at the magnification shown in your screenshots you should probably be using PhotoShop or PaintShop Pro to make them as graphical objects anyway, that would produce much better results.) One trick I sometimes use is to create a callout without any text, then I can antialias its outline. Then I create a text object with crisp, non antialiased text and position it over the callout.

Hi Tim,

No, I'm not using them at that size. I magnified them to make the
difference clear.

I agree that text looks better without anti-aliasing. But I'm inclined to
use a bitmap font, such as MS Sans Serif, in preference to TrueType
Arial if it can't be smoothed. What are the pros and cons of doing that?

What's puzzling is why the text isn't smoothed? With smoothing switched
on just about every other chunk of text on my computer, in lots of
different apps, gets smoothed. And when I use the Windows API DrawText
functions in my own programming, smoothing works just fine without any
extra effort on my part.

Presumably in Impict text is not being drawn on the final canvas, whereas
the font smoothing function obviously needs to know the background
colour.

Thanks anyway,

Martin.

[Tim Green]

I'm not sure but I would guess that the reason font smoothing is not applied is that it's a display technology, designed to make text appear better on the screen. In Impict or any other graphics program you are working with text while you are editing, but what you are outputting is a graphic image, which by definition is not smoothed -- font smoothing happens interactively on the screen while the user is viewing it. I'm not entirely sure, but I don't think I've ever seen a graphics program apply Windows font smoothing and then save it as a graphic.

As I said, this is a guess -- if you need details on the technical aspects try contacting the programmers at EC directly at support AT ec-software.com.

[Martin Wynne]

.... I'm not entirely sure, but I don't think I've ever seen a graphics program apply Windows font smoothing and then save it as a graphic....

Hi Tim,

They often do. Attached for example is some text on a bitmap
created by Windows Paint.

My own graphics programs work the same way - the API DrawText
function uses the background colour of the bitmap canvas to create
the smoothing effect when creating each character image.

Which is why I was puzzled by its not working in Impict. Having thought
more about it, I think it is because text and background are stored as
separate bitmaps in the Impict format, and are simply combined when
the image is rendered, instead of re-drawing the text on the layer below it.

regards,

Martin.

[Alexander Halser]

I'll check if there's anything we could do better in Impict.

The reason why font smoothing (= anti-aliasing) works differently in Impict, is that Impict has it's own functions for that. When a graphics program inserts a text into a bitmap, the standard Windows font smoothing may apply or may not apply. This depends on whether the graphics program created a device dependent bitmap (DDB = a bitmap that has the same capabilities as the display) or a so-called device independent bitmap (DIB). With a DDB, Windows automatically applies font smoothing when you render text on it, on a DIB it does not. Presumed that font smoothing is available by the operating system - older OS versions did not all have this function. Impict strictly uses DIBs, so we have no system font smoothing available and need to do it manually.

Device dependent bitmaps work fine on a true color display but fail when you create them on a limited display, because they have the same capabilities (color depth) as the display device. DIBs, on the other hand, may not look as good on a limited display but their original color depth is independent from the device. Impict needs device independent true color bitmaps to create the transparency and shadow effects.

[Martin Wynne]

I'll check if there's anything we could do better in Impict. ...
... Impict needs device independent true color bitmaps to create the transparency and shadow effects.

Hi Alexander,

Many thanks for the explanation. The transparency and shadow effects
are brilliant, so if it takes a DIB to do that, I'm happy to settle for no font
smoothing for the text.

regards,

Martin.