First version of display rotation, inspired by gimp-painter.
The rotation always happens around the image's center.
The only "UI" for rotating is currently shift+middle-drag and
shift+space-drag. Control constrains the angle to 15 degrees
and is currently the only way to go back to "no rotation".
by not manually intersecting and subtracting regions at all. Simply
clip the cairo_t to the area we want to render, it will automatically
intersect with the clip region from the expose event, and check if the
clip is empty before actually drawing anything.
the changes are simply copied from the gtk3-port branch, reducing the
number of diffs, and enabling hacking on drawing stuff in master while
keeping the branch easily rebasable.
Recent Cairo uses SHM transports when available, and exposes the ability
for its users to manage images shared between it and the display.
This allows us to eliminate copies, and if the architecture supports it
even to upload directly into GPU addressable memory without any copies
(all in normal system memory so we suffer no performance penalty when
applying the filters). The caveat is that we need to be aware of the
synchronize requirements, the cairo_surface_flush and
cairo_surface_mark_dirty, around access to the transport image. To
reduce the frequency of these barriers, we can subdivide the transport
image into small chunks as to satisfy individual updates and delay the
synchronisation barrier until we are forced to reuse earlier pixels.
Note this bumps the required Cairo version to 1.12, and please be aware
that the XSHM transport requires bug fixes from cairo.git (will be
1.12.12)
v2: After further reflections with Mitch, we realized we can share the
transport surface between all canvases by attaching it to the common
screen.
v3: Fix a couple of typos in insert_node() introduced when switching
variables names.
v4: Encapsulating within an image surface rather than a subsurface was
hiding the backing SHM segment from cairo, causing it to allocate
further SHM resources to stream the upload. We should be able to use a
sub-surface here, but it is more convenient to wrap the pixels in an
image surface for rendering the filters (and conveniently masking the
callee flushes from invalidating our parent transport surface).
Cc: Michael Natterer <mitch@gimp.org>
instead of checking for event->button == 3, so context menus
work correctly on the Mac. Didn't change the image menu yet
because thet requires some more refactoring.
And remove all the complicated handling code entirely. This makes
GimpTransformTool a lot less complex. As a nice side effect, the
preview is now always 100% in sync with the grid and handles.
This was only there to make sure XOR drawing works, and is now
complete overhead since cairo drawing is done *in* expose, and not in
some hack around it.
Spit warnings in the functions if grabbing fails and return a boolean
success value. Bail out in the callers upon grab failure instead of
assuming that grabbing always succeeds and running into an
inconsistent state that can cause all sorts of problems.
- replace gimp_display_shell_selection_control() by undraw() and restart()
which actually say what they are doing
- remove enum GimpSelectionControl
- replace GimpImage::selection_control() by ::selection_invalidate()
because none of the other enum values was used any longer
which is the last bit of non-item drawing of stuff that is not
somehow the image itself... wheee!
This involves reverting commit
6bce0641d4 and adding back all the
vectors handlers that were in gimpdisplayshell-callbacks.c before.
Change the callbacks to manage proxy items for all the image's
vectors.
- Add signals GimpImage::guide_added(), removed() and moved()
- Remove singal GimpImage::update_guide()
- Adapt core code to emit the new signals instead of update_guide()
- Have the shell connect to the new signals and update guide canvas
items as needed
- Remove gimp_display_shell_draw_guides()
- Add GimpImage signal "sample-point-moved" and emit it when needed
- Let the shell connect to the sample point add, remove and move signals
and update the canvas items accordingly
- Remove gimp_display_shell_draw_sample_points()
- Invalidate the proper area when an item gets added or removed.
- Draw the kept canvas items instead of calling a draw tool function.
- The draw tool now sets its item on the shell.
Instead of blending the scaled image data onto the checkerboard and
then painting this image to the screen, render the image data into
an ARGB cairo image surface. Then paint a checkerboard on the canvas
and the image on top of it.