This API does:
- Take a Utf8View
- Take the starting point on the baseline as its input coordinate
This API does not:
- Align the text
- Wrap the text
- Elide too-long text into "..."
This necessitates switching from passing a single code point to the
callback to passing a non-const Utf8CodePointIterator instead.
Note that the text selection mechanisms in LibGUI and LibWeb don't
handle this properly yet; they still assume that each code point
renders as one glyph. Similarly, width calculations for text widths
don't either, so a single such an emoji will require space for more
than one glyph.
It also doesn't work in LibVT's TerminalWidget, where each code point
is handled and rendered separately, so LibGfx never gets a chance to
check if subsequent code points could result in a combined emoji.
This patch adds support for drawing triangular waves.
For now those can only be horizontal, but as they are intended for
underlining text, it's an okay way to handle this.
The algorithm is quite simple: You grab a 2x2 area of pixels around the
point you want from the source bitmap, and then linearly interpolate
between them based on how far they are from that point.
This works well when scaling up images, and moderately well when scaling
down - small details may get skipped over. The way GPUs solve this is
with mipmaps, which is not something I want to get into right now. (And
increases the memory usage per bitmap by 50%.)
I have not focused on performance, but this does reuse much of the
existing fixed-point calculation, and uses constexpr so that the
performance for nearest-neighbor should be the same as it was
previously.
Previously there was no way to draw rectangles with any specific
thickness, like we can do with ellises, for instance. This method
is just a simple wrapper around `draw_line()` several times. At
least for now, we don't need to do anything sophisticated since
this will only be used by PixelPaint.`
This class now contains all the fun bits about laying out text in a
rect. It will handle line wrapping at a certain width, cutting off lines
that don't fit the given rect, and handling text elision.
Painter::draw_text now internally uses this.
Future work here would be not laying out text twice (once actually
preparing the lines to be rendered and once to get the bounding box),
and possibly adding left elision if necessary.
Additionally, this commit makes the Utf32View versions of
Painter::draw_text convert to Utf8View internally. The intention is to
completely remove those versions, but they're kept at the moment to keep
the scope of this PR small.
This adds a function to draw a circle specified by a center point (
relative to the given Rect) and a radius. The circle arc is only drawn
inside the specified Rect as to allow for circle arc segments.
Technically this was already possible using draw_elliptical_arc(), but
the algorithm is quite involved and lead to wonky arcs when trying to
draw circle arc segments.
This commit adds a draw_physical_line method, which is the exact same
as draw_line, except it's parameters are already transformed and
scaled. This is used by both draw_line and draw_rect, as a slight
optimization to save some work. It also fixed draw_rect not checking
whether it should draw the lines before drawing them.
This allows the painter to be scaled separately in both directions, and
not just in integer intervals. This is crucial for proper SVG viewBox
support.
Most bitmap-related things verify the scale to be one as of now.
This commit unifies methods and method/param names between the above
classes, as well as adds [[nodiscard]] and ALWAYS_INLINE where
appropriate. It also renamed the various move_by methods to
translate_by, as that more closely matches the transformation
terminology.
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 *
It was previously using draw_tiled_bitmap, which always aligns the
tiles with the global origin and does not respect the alpha of the
source. Switch to a new Painter::blit_tiled helper which uses
Painter::blit under the hood, which has more correct behavior.
Rather than invalidating the entire window, which is very expensive on
the transparent desktop widget, just invalidate the areas that actually
need updating.
(...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.
This implements simple window shadows around most windows, including
tooltips. Because this method uses a bitmap for the shadow bits,
it is limited to rectangular window frames. For non-rectangular
window frames we'll need to implement a more sophisticated algorithm.
Consider
draw_scaled_bitmap({0, 0, 10, 10}, source, {0, 0, 5, 5}).
Imagine wanting to split that up into two calls, like e.g. the
compositor when redrawing the background with damage rects. You really
want to be able to say
draw_scaled_bitmap({0, 0, 5, 10}, source, {0, 0, 2.5, 5})
but up to now you couldn't. Now you can.
This makes painting very low-res images (such as tile.png) in mode
"stretch" work much better.
draw_scaled_bitmap() has a clearer API (just source and dest rects --
blit_scaled() took those and scale factors and then ignored width and
height on the source rect and it was less clear what it was supposed to
do), and they do mostly the same thing.
The draw_scaled_bitmap() API takes an IntRect as source rect, so it's
currently not always possible to split a big draw_scaled_bitmap() into
two (or more) smaller draw_scaled_bitmap() calls that do the same thing
-- that'd require FloatRects. The compositor kind of wants this to be
possible, but there's already a FIXME about this not looking quite right
with the previous approach either.
draw_scaled_bitmap() handles transparent sources, so after this change
wallpapers with transparency will be blended instead of copied. But that
seems fine, and if not, the Right Fix for that is to remove the alpha
channel from wallpapers after loading them anyways.
As an added bonus, draw_scaled_bitmap() already handles display scale,
so this fixes window server asserts for background images that are shown
as "stretch" (#5017). The window server still asserts for "tile" and
"offset" for now though.
Calling draw_scaled_bitmap() here exposed a bug in it fixed by #5041.
Before that is merged, this change here will cause smearing on the
background image when moving windows around.
Moves Painter away from general affine transport support a bit, but
this scale factor business does feel like it's a bit different.
This is conceptually cleaner (everything should use logical coordinates
as much as possible), and it means the code in GUI::Painter() will work
without changes due to that, but the draw function implementations
overall get a bit murkier (draw_rect() becomes nicer though). Still,
feels like the right direction.
No behavior change.
Gfx::Bitmap can now store its scale factor. Normally it's 1, but
in high dpi mode it can be 2.
If a Bitmap with a scale factor of 2 is blitted to a Painter with
scale factor of 2, the pixels can be copied over without any resampling.
(When blitting a Bitmap with a scale factor of 1 to a Painter with scale
factor of 2, the Bitmap is painted at twice its width and height at
paint time. Blitting a Bitmap with a scale factor of 2 to a Painter with
scale factor 1 is not supported.)
A Bitmap with scale factor of 2 reports the same width() and height() as
one with scale factor 1. That's important because many places in the
codebase use a bitmap's width() and height() to layout Widgets, and all
widget coordinates are in logical coordinates as well, per
Documentation/HighDPI.md.
Bitmap grows physical_width() / physical_height() to access the actual
pixel size. Update a few callers that work with pixels to call this
instead.
Make Painter's constructor take its scale factor from the target bitmap
that's passed in, and update its various blit() methods to handle
blitting a 2x bitmap to a 2x painter. This allows removing some gnarly
code in Compositor. (In return, put some new gnarly code in
LibGfxScaleDemo to preserve behavior there.)
No intended behavior change.
Needed for the window server minimize animation.
draw_rect() can't just call draw_line() because that isn't
draw_op()-aware. The draw_op()-awareness in Painter looks a bit ad-hoc,
but that's for another day.
This adds a scale factor to Painter, which will be used for HighDPI
support. It's also a step towards general affine transforms on Painters.
All of Painter's public API takes logical coordinates, while some
internals deal with physical coordinates now. If scale == 1, logical
and physical coordinates are the same. For scale == 2, a 200x100 bitmap
would be covered by a logical {0, 0, 100, 50} rect, while its physical
size would be {0, 0, 200, 100}.
Most of Painter's functions just assert that scale() == 1 is for now,
but most functions called by WindowServer are updated to handle
arbitrary (integer) scale.
Also add a new Demo "LibGfxScaleDemo" that covers the converted
functions and that can be used to iteratively add scaling support
to more functions.
To make Painter's interface deal with logical coordinates only,
make translation() and clip_rect() non-public.
