The event wasn't fired when the window size got changed through an API
call. Unfortunately after this change the event gets fired any time
I call setMaxWindowSize(), not just when the size changes.
On Emscripten as well, however I'm keeping the Configuration::setTitle()
a no-op because the title is usually set by the HTML markup already and
so dynamic code implicitly changing it to something else doesn't make
much sense.
Deprecated for 2018.04, it's been almost a year since. Whoever is using
Magnum regularly updated already, and who not can always upgrade
gradually (2018.02, 2018.04, 2018.10, 2019.01 etc.).
This took me a while -- the old behavior for all emscripten_*()
functions was to take a DOM element ID as an argument, with nullptr
acting as a "the element that makes most sense for given operation". The
new behavior when -s DISABLE_DEPRECATED_FIND_EVENT_TARGET_BEHAVIOR=1 is
enabled is to take a CSS selector instead. Presence of this option is
not detectable at compile time, so there was no easy way of knowing
what's the expected value, whether `"module"` or `"#module"`.
After a few failed attempts, I discoverd that using `"#canvas"` would
work for both the old and the new version -- in the new version it would
be selecting an element with id="canvas", while in the old version it
was a special value denoting Module['canvas']. Problem was, however,
that the markup was historically using id="module" and not id="canvas",
so this had to be changed.
This is a breaking change affecting everyone who targets Emscripten. You
need to update the HTML markup and, in case you maintain copies or forks
of the CSS and JS files, these as well. Details in the changelog.
It's enabled by default, but it's possible to explicitly remove the flag
to allow for using features that are not enabled otherwise (such as wide
lines). To make the flag handling easier, there's now also new
addFlags() and clearFlags() methods.
With HiDPI support it's no longer just about window size changing -- if
the framebuffer size is different than window size, on resize both are
changed to new (different) values. Other than that, for example, when
moving a window from one display to another with a different DPI,
all three of window size, framebuffer size and DPI scaling can change as
well. This should be all reflected in the event.
This change is done in all Application classes, but the full
implementation is only in the SDL2 implementation at the moment, as the
others don't have full HiDPI support implemented yet. The old
viewportEvent(const Vector2i&) is deprecated and for backwards
compatibility called with either framebufferSize() or windowSize()
(depending on level of HiDPI support) from the new event. Overriding the
old one will still work as expected (in case you build with
MAGNUM_BUILD_DEPRECATED enabled and use the `override` keyword -- which
you should); overriding the new one will cause the compat implementation
to not be called anymore.
In order to make it possible to preserve backwards compatibility, the
viewportEvent() is no longer pure virtual in Screen. That's also
consistent with all Application implementations.
I'm not really sure if the extra work and link dependencies are worth
the warning, but since I *need* to do something similar for Windows, why
not have it here as well.
This is quite complex, actually. The end goal is: when I request an
800x600 window, it should create a window of the same physical size as
an 800x600 window would have on a system default DPI. After that, the
actual window size (for events), framebuffer size and DPI scaling value
(to correctly scale the contents relative to window size) are
platform-dependent.
On macOS and iOS, the DPI scaling is done simply by having the
framebuffer twice the size while the window size (for events) remains
the same. Easy to support.
On Linux, a non-DPI-aware app is simply having a really tiny window. The
worst behavior of all systems. Next to that, SDL_GetDisplayDPI() returns
physical DPI, which is quite useless as the value is usually coming from
Xorg display autodetection and is usually just 96, unless one goes extra
lengths and supplies a correct value via an xorg.conf. The DE is using a
different, user-configurable value for scaling the visuals and this one
is available through a Xft.dpi property. To get it, we dlopen() self and
dlsym() X11 symbols to get this property. If this fails, it might mean
the app doesn't run on X11 (maybe Wayland, maybe something's just messed
up, who knows) and then we fall back to SDL_GetDisplayDPI(). Which is
usually very wrong, so this is also why I'm implementing two ways to
override this -- either via the app Configuration or via a command-line
/ environment variable.
On Emscripten / HTML5, all that's needed is querying device pixel ratio
and then requesting canvas size scaled by that. The event coordinates
are relative to this size, so there's not much more to handle. Physical
canvas size on the page is controlled via CSS, so no issues with stuff
being too big or too small apply -- in the worst case, things may
be blurry.
On Windows, the DPI scaling is something in-between -- if the app
presents itself as DPI-aware, window size is treated as real pixels (so
one gets really what is asked for, i.e. an 800x600 window on a system
with 240 DPI is maybe four centimeters wide). If not, the window is
upscaled (and blurried) by the compositor. In order to have correct
behavior, I first need to query if the app is DPI-aware and then either
scale the requested size or not (to avoid extra huge windows when the
app is not marked as DPI aware). That will be done in a later commit.
Vladimír Vondruš