Originally I simply thought that passing file paths is quite OK, but as
Linus pointed to, it turned out that passing file paths to ensure some
files are able to be decoded is awkward because it does not work with
images being served over HTTP.
Therefore, ideally we should just use the MIME type as an optional
argument to ensure that we can always fallback to use that in case
sniffing for the correct image type has failed so we can still detect
files like with the TGA format, which has no magic bytes.
Because TGA images don't have magic bytes as a signature to be detected,
instead assume a sequence of ReadonlyBytes is a possible TGA image only
if we are given a path so we could check the extension of the file and
see if it's a TGA image.
When we know the path of the file being loaded, we will try to first
check its extension, and only if there's no match to a known decoder,
based on simple extension lookup, then we would probe for other formats
as usual with the normal sniffing method.
The getters passed to REGISTER_STRING_PROPERTY are never invoked. But if
they were, they would errantly incur an implicit pointer-to-boolean cast
when their return type (Gfx::Bitmap*) is used to construct a JsonValue.
To transparently support multi-frame images, all decoder plugins have
already been updated to return their only bitmap for frame(0).
This patch completes the remaining cleanup work by removing the
ImageDecoder::bitmap() API and having all clients call frame() instead.
Previously, ImageDecoder::create() would return a NonnullRefPtr and
could not "fail", although the returned decoder may be "invalid" which
you then had to check anyway.
The new interface looks like this:
static RefPtr<Gfx::ImageDecoder> try_create(ReadonlyBytes);
This simplifies ImageDecoder since it no longer has to worry about its
validity. Client code gets slightly clearer as well.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
With a little help (read: copy & paste) from ImageWidget, QuickShow will
now cycle through the frames of animated images - enjoy the cat GIFs!
Future improvement: cache decoded images like LibWeb's ImageResource to
waste less CPU - the same applies to LibGUI though, maybe we can put
something shared in LibGfx.
Closes#5837.
The image decoder already tells us whether the image is animated and it
can provide more than one frame, let's not put this behind an artificial
"file path must end with lowercase .gif" barrier.
(...and ASSERT_NOT_REACHED => VERIFY_NOT_REACHED)
Since all of these checks are done in release builds as well,
let's rename them to VERIFY to prevent confusion, as everyone is
used to assertions being compiled out in release.
We can introduce a new ASSERT macro that is specifically for debug
checks, but I'm doing this wholesale conversion first since we've
accumulated thousands of these already, and it's not immediately
obvious which ones are suitable for ASSERT.
