I have windows that are fixed in size, under which I have textual labels. Although I use the same font, the fonts look different on windows, mac and linux, up to the point where I can't rely on where a label will end, even though the string and the font size are a constant in my application.
Is there any solution to that? Someone mentioned embedding TTF fonts and using them, but is that really necessary?
There is no font you can rely on being available on all platforms, and height/width ratios for different strings will differ for different fonts (fixed-width being slightly better). Additionally, things like different DPI settings will cause you headaches even if using the same font. I would rather reconsider whether your widgets really should be fixed size and you need those assumptions about the font size at all. In almost all cases, your UI will be more usable, readable and consistent with the rest of the desktop if you use flexible layouts and stick to whatever font and font size the platform suggests.
You can use QFont::setPixelSize to guarantee a consistent font size across platforms.
Since the goal is to keep a line of text label from drawing over and out of the window bounds, one solution is to adjust the font size used at runtime.
QFontMetrics provides boundingRect() family of calls to find how must space a text string will take when drawing in a given font. With those, you can test if the string can fit in the space. If it doesn't fit, reduce the font size and test again.
Related
I want to specify two different fonts in a font-family (font-family:A, B;) but the sizes of these two fonts are different.
It seems font-size-adjust onlys work in Firefox. So how can I adjust second font size if the first one is not available?
You cannot. The conclusion is that you should list only fonts that are sufficiently similar in their properties.
Well, there are some tricks used to detect the availability of a font on the basis of its properties. You could use font A (only) for an invisible inline test element containing some text and then compare, using JavaScript, the width of the test element with its measured width (allowing some small difference, since different implementations of font A may yield slightly different widths). If the widths don’t match, you would change the font size setting for the element(s) that have font-family: A, B, so that the size is suitable for B. Well, you would still have the problem that font B might not be available either. So it would be messy, with no real guarantee of success.
You are right, font-size-adjust isn't standard, and is hence won't work.
I think that the best way to solve your problem isn't to try and work around two completely different font sizes, but to select two fonts that are sufficiently similar as so the sizing is consistent.
Preferably, I would use Web Fonts (Also, http://www.google.com/fonts is a good place to start), so ensure that everyone gets the same experience, and you can load consistent, beautiful fonts across browsers and platforms. If the performance hit is a problem, then consider using reliable font stacks.
I understand that this isn't a strict answer to your question, but it may be a better way to go. :)
I've tried using em as well as px, but I cannot get a certain line of text to display at the same size in every browser. I know I'm reaching for a lot but I'm tasked with achieving a pixel-perfect development based on a mock-up, and need a certain text to span the width of an area left-to-right so that it all flushes from side to side with an image.
My last option is to use an image, which I don't want to do. I know that you can specify certain CSS parameters that work on the different browsers such as -moz-SOMECSSPROPERTY:some value; but can you do this with the font size so that one browser has it at one size, and another as another. Oddly enough too though this is actually only happening in the browsers that are on different OS's, i.e. - on my Mac it's as intended, and on Windows (same browsers) different.
Thanks for advice.
It won't be enough to specify the font on a per-browser basis, because (as you noticed) you'll also run into inconsistencies across platforms and devices.
If you want the text to always fit the image flush, the text pretty much has to be an image, too.
I have a fixed strip I'm drawing, 50 pixels in height and as wide as my application main window.
I'd like to place text on that strip.
My problem is that even with the same font and size (arial 15 for example), the font will have a different height under OSX and Windows.
Is there a way to make this more predictable? I know I can use the QFont measuring mechanism until the extent of the text I need will match my target projection area, more or less. but is there another way to set size that'll be identical across operating systems? Just want to make sure I'm not missing something here.
You can specify font heights in pixels using QFont::setPixelSize(). It's particularly handy when drawing text over fixed sized bitmaps.
I still use EM's in the CSS to specify the sizes of elements in my templates.
Today most browsers are able to correctly scale websites where the sizes are given in PX.
My argument for using EM's was / is: if a person that has a sight disability and changes the base font size in the browser, the design still fits.
I'm asking because for me its still a source of errors to use EM's. When i specify a different font-size then the base font-size on a element, I often forget to adapt my EM calculation for the children elements.
Now i have 2 questions:
How do people with a sight
disability configure the browser (do
they use the browser zoom or do they
still change the base font-size)?
Does it still make sense to use EM's
for element sizes nowadays?
Based on what I've read, neither. Users with mild-to-moderate sight difficulties often use applications distinct from the UA itself to provide zooming functions. These tools can magnify all or part of a display, but (in my limited experience) they don't zoom the text out-of-relation to the setting.
It still makes sense to use 'em'. First of all, accessibility isn't the only reason to use 'ems'. I think the inheritance model of relative sizes makes more sense with ems and percentages than it does with pixels. Second, you can do calculations in CSS3 itself, if it helps you to not need to remember to adapt your calculations.
refs:
http://www.championinternet.com/rwa/Ann.pdf
http://davidbcalhoun.com/2010/does-it-still-make-sense-to-use-em-rather-than-px
http://www.w3.org/TR/css3-values/#calc
Physical dimensions (px) are generally worse than logical (pt, em, %) because physical devices' size and resolution may vary wildly (from a small handset to a desktop screen to a wall-mounted plasma screen). Unless you're tightly bound to a piece of raster graphics, there should not be any disadvantage in specifying dimensions in logical units.
If you always specify font sizes as percent of base size, it's harder to forget to use the logical units :) Also a user can just specify base font size in the browser and your entire design adapts automatically.
When font size is too small for me to read, I zoom a little. Also I specify quite large base size for Japanese pages so that I can make out the glyphs. But if a page resists to adapt to font change, I usually just hit my 'Readability' bookmarklet, and the offending design disappears completely.
I'm still in favor of using EM as a unit. But like you said, modern browser scales size pretty well even with other units.
I think the most important is to always use the same unit across the website. As long as you don't start to mix different unit, the browser should handle everything well.
The only real advantage I see nowadays to use EM, is that someone who has increased is default font size will see your site with bigger elements without doing anything. If you use PX, the person probably have to change the size manually.
I read somewhere on a site :
In principle, using a px measurement for font-size is not a good idea. A handful of browsers will prevent the font from being resized by the user if you do this.
Is this right??
Is this right??
Well, yes, certainly there are a few (generally older) browsers that won't let you resize the text when it's sized in px, pt, in, mm and so on.
But even in browsers with a working zoom, it's polite to work relative to the user's stated preference for font size, so they don't have to resize the text or zoom the page manually to make it comfortable. (Fixed fonts plus fixed width page can be particularly bad for this in page-zooming browsers as zooming up is likely to make the columns of text too wide to fit the screen.)
In principle, using a px measurement for font-size is not a good idea.
I wouldn't go so far as to say it's always a bad idea.
There are often elements on the page where you want the text to be sized to match an image (say, a header with text below it that should fit more-or-less without wrapping, or text above a background image made to fit it). In that case you should use px to make fonts and images line up nicely.
For the page's main body text, yes, it's nicer to use em/% and let the user decide the size. But for text that plays a part in the page's graphical layout, px fonts are typically the best bet.
The issue is mainly with aspect ratio. Let's say my resolution is 1024x768 for an aspect ratio of 1.33. For 1920x1080, the aspect ratio becomes 1.77, meaning that any image displayed at a specific pixel width and height will be a different size in inches due to the scaling effect of the aspect ratio. The same basic issue exists if you zoom as you are effectively using the aspect ratio in the zoom window.
Most websites get around this by using em which, to be honest, suffers from some of the same downfalls as any other rendering mode. Even "device independent pixels" are based on the DPI of a monitor. So, use em knowing that it just has less faults than px, not because it's perfect.
Read the following article if you want a more in depth study.
http://www.w3.org/WAI/GL/css2em.htm
Yes, at least IE6 & IE7 do that. Take a look at How to Size Text in CSS.
Quoting CSS: The Definitive Guide by Eric Meyer
There is one more value that is
potentially the same as 36pt, and
that's 36px, which would be the same
physical distance if the display
medium is 72 pixels-per-inch (ppi).
However, there are very few monitors
with that setting anymore. Most are
much higher, in the range of 96ppi to
120ppi. Many very old Macintosh web
browsers treat points and pixels as
though they are equivalent, so the
values 14pt and 14px may look the same
on them. This is not, however, the
case for Windows and other platforms,
including Mac OS X, which is one of
the primary reasons why points can be
a very difficult measurement to use in
document design.
Because of these variations between
operating systems, many authors choose
to use pixel values for font sizes.
This approach is especially attractive
when mixing text and images on a web
page, since text can (in theory) be
set to the same height as graphic
elements on the page by declaring
font-size: 11px; or something similar,
as illustrated by Figure 5-15.
Using pixel measurements for font-size
is certainly one way to get
"consistent" results with font-size
(and, indeed, with any length at all),
but there is a major drawback.
Internet Explorer for Windows up
through Version 6.0 does not allow
users to easily resize text that has
been set with pixels. Other browsers,
including Mozilla, Netscape 6+,
IE5+/Mac, Opera, and even IE7, allow
the user to resize text no matter how
it's been set. Thus, using pixels to
size text is no more of a guarantee
that it will stay the same size than
is any other method. The other
approaches discussed in this chapter,
such as keywords and percentages, are
a much more robust (and user-friendly)
way to go, as they can be used to
scale text from the user's default
font size.
That said, the issue here is what unit to use for your body element. In most cases, you should use the em unit for other elements like headings and paragraphs.