This means that a request to (re)draw the Rect (0.5,0.5,9.5,9.5)
will actually generate an expose event for (0,0,10,10)
Note: the above rects are of the form (x0,y0,x1,y1)
Items call ::queue_resize(), which sets a flag in the canvas; at next idle, we call
Canvas::layout() which walks the item tree and recursively calls layout (depth first)
on all items needing a resize.
Only Container types implement layout, and so far only Box
This partially reverts 2edbda2526.
Using cairo-groups increases performance on MacOS, and retains
retina-resolution.
However it adds a performance regression for MS Windows graphics
rendering. cairo-groups use a "similar" surface, not an image surface.
Empirically this adds significant overhead compared to rendering
using the CPU and using bitblt.
For MacOS/X this is equivalent, rendering happens using a
CGBitmapContext + image-surface. Windows and Linux needs profiling
for respective equivalent surfaces.
This is an intermediate commit, before replacing image surfaces with
cairo pattern groups.
The eventual goal is to reduce flickering and/or use
CPU + bitblt for specific widgets instead of cairo
graphics-cards accel.
This also removes excessive calls to getenv() for every rendering
operation.
Called when an item has requested a redraw and intersects with visible
canvas area.
Also add Canvas::prepare_for_render that will call Item::prepare_for_render for
items visible on the canvas.
Various GdkEvents are not yet handled correctly, eg. unpacking a widget
from its container does not unmap it, nor are remaining widgets in the
contained re-positioned (size allocation does not change, nor does the
mapping). This affects eg. Mixbus Strips
Backport from Mixbus. In Ardour this does not currently matter
since there is no top-level canvas destroyed top-down.
...
Editor::session_going_away
MixerStrip::~MixerStrip
MixbusStripCanvas::~MixbusStripCanvas
ArdourCanvas::GtkCanvas::~GtkCanvas
ArdourCanvas::Canvas::~Canvas
ArdourCanvas::Root::~Root
ArdourCanvas::Container::~Container
ArdourCanvas::Item::~Item
ArdourCanvas::Item::clear_items
GtkCanvas::item_going_away()
queue_draw_item_area()
..expose can take place async to garbage collection: crash in one of the
items.
Mixbus in particular uses both types of tooltip so we might as well make them look the same.
N.B. The appearance is fine now on Windows but needs to be tested on the other platforms (i.e. some tweaking might be necessary).
All canvas objects share just one tooltip object which is based around Gtk::Label. The Label expands if the current tooltip text is wider than the previous text. However, it doesn't shrink again if the next tooltip has shorter text. Eventually, this results in some very strange looking tooltips (especially in Mixbus where they're used quite extensively).
Deleting the object after use will force a new object to get generated next time (at the correct size). There's still only ever one object per canvas but it's no longer persistent.
Gtk coalesces multiple exposes into a single combined rect.
If _single_exposure is disabled, we break apart the individual expose rects for the canvas rendering.
