mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-11-27 20:21:24 +00:00
210 lines
9 KiB
XML
210 lines
9 KiB
XML
<?xml version="1.0" encoding="UTF-8"?>
|
|
<protocol name="scaler">
|
|
|
|
<copyright>
|
|
Copyright © 2013-2014 Collabora, Ltd.
|
|
|
|
Permission to use, copy, modify, distribute, and sell this
|
|
software and its documentation for any purpose is hereby granted
|
|
without fee, provided that the above copyright notice appear in
|
|
all copies and that both that copyright notice and this permission
|
|
notice appear in supporting documentation, and that the name of
|
|
the copyright holders not be used in advertising or publicity
|
|
pertaining to distribution of the software without specific,
|
|
written prior permission. The copyright holders make no
|
|
representations about the suitability of this software for any
|
|
purpose. It is provided "as is" without express or implied
|
|
warranty.
|
|
|
|
THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
|
|
SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
|
|
FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
|
|
SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
|
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
|
|
AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
|
|
ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
|
|
THIS SOFTWARE.
|
|
</copyright>
|
|
|
|
<interface name="wl_scaler" version="2">
|
|
<description summary="surface cropping and scaling">
|
|
The global interface exposing surface cropping and scaling
|
|
capabilities is used to instantiate an interface extension for a
|
|
wl_surface object. This extended interface will then allow
|
|
cropping and scaling the surface contents, effectively
|
|
disconnecting the direct relationship between the buffer and the
|
|
surface size.
|
|
</description>
|
|
|
|
<request name="destroy" type="destructor">
|
|
<description summary="unbind from the cropping and scaling interface">
|
|
Informs the server that the client will not be using this
|
|
protocol object anymore. This does not affect any other objects,
|
|
wl_viewport objects included.
|
|
</description>
|
|
</request>
|
|
|
|
<enum name="error">
|
|
<entry name="viewport_exists" value="0"
|
|
summary="the surface already has a viewport object associated"/>
|
|
</enum>
|
|
|
|
<request name="get_viewport">
|
|
<description summary="extend surface interface for crop and scale">
|
|
Instantiate an interface extension for the given wl_surface to
|
|
crop and scale its content. If the given wl_surface already has
|
|
a wl_viewport object associated, the viewport_exists
|
|
protocol error is raised.
|
|
</description>
|
|
|
|
<arg name="id" type="new_id" interface="wl_viewport"
|
|
summary="the new viewport interface id"/>
|
|
<arg name="surface" type="object" interface="wl_surface"
|
|
summary="the surface"/>
|
|
</request>
|
|
</interface>
|
|
|
|
<interface name="wl_viewport" version="2">
|
|
<description summary="crop and scale interface to a wl_surface">
|
|
An additional interface to a wl_surface object, which allows the
|
|
client to specify the cropping and scaling of the surface
|
|
contents.
|
|
|
|
This interface allows to define the source rectangle (src_x,
|
|
src_y, src_width, src_height) from where to take the wl_buffer
|
|
contents, and scale that to destination size (dst_width,
|
|
dst_height). This state is double-buffered, and is applied on the
|
|
next wl_surface.commit.
|
|
|
|
The two parts of crop and scale state are independent: the source
|
|
rectangle, and the destination size. Initially both are unset, that
|
|
is, no scaling is applied. The whole of the current wl_buffer is
|
|
used as the source, and the surface size is as defined in
|
|
wl_surface.attach.
|
|
|
|
If the destination size is set, it causes the surface size to become
|
|
dst_width, dst_height. The source (rectangle) is scaled to exactly
|
|
this size. This overrides whatever the attached wl_buffer size is,
|
|
unless the wl_buffer is NULL. If the wl_buffer is NULL, the surface
|
|
has no content and therefore no size. Otherwise, the size is always
|
|
at least 1x1 in surface coordinates.
|
|
|
|
If the source rectangle is set, it defines what area of the
|
|
wl_buffer is taken as the source. If the source rectangle is set and
|
|
the destination size is not set, the surface size becomes the source
|
|
rectangle size rounded up to the nearest integer. If the source size
|
|
is already exactly integers, this results in cropping without scaling.
|
|
|
|
The coordinate transformations from buffer pixel coordinates up to
|
|
the surface-local coordinates happen in the following order:
|
|
1. buffer_transform (wl_surface.set_buffer_transform)
|
|
2. buffer_scale (wl_surface.set_buffer_scale)
|
|
3. crop and scale (wl_viewport.set*)
|
|
This means, that the source rectangle coordinates of crop and scale
|
|
are given in the coordinates after the buffer transform and scale,
|
|
i.e. in the coordinates that would be the surface-local coordinates
|
|
if the crop and scale was not applied.
|
|
|
|
If the source rectangle is partially or completely outside of the
|
|
wl_buffer, then the surface contents are undefined (not void), and
|
|
the surface size is still dst_width, dst_height.
|
|
|
|
The x, y arguments of wl_surface.attach are applied as normal to
|
|
the surface. They indicate how many pixels to remove from the
|
|
surface size from the left and the top. In other words, they are
|
|
still in the surface-local coordinate system, just like dst_width
|
|
and dst_height are.
|
|
|
|
If the wl_surface associated with the wl_viewport is destroyed,
|
|
the wl_viewport object becomes inert.
|
|
|
|
If the wl_viewport object is destroyed, the crop and scale
|
|
state is removed from the wl_surface. The change will be applied
|
|
on the next wl_surface.commit.
|
|
</description>
|
|
|
|
<request name="destroy" type="destructor">
|
|
<description summary="remove scaling and cropping from the surface">
|
|
The associated wl_surface's crop and scale state is removed.
|
|
The change is applied on the next wl_surface.commit.
|
|
</description>
|
|
</request>
|
|
|
|
<enum name="error">
|
|
<entry name="bad_value" value="0"
|
|
summary="negative or zero values in width or height"/>
|
|
</enum>
|
|
|
|
<request name="set">
|
|
<description summary="set the crop and scale state">
|
|
Set both source rectangle and destination size of the associated
|
|
wl_surface. See wl_viewport for the description, and relation to
|
|
the wl_buffer size.
|
|
|
|
The bad_value protocol error is raised if src_width or
|
|
src_height is negative, or if dst_width or dst_height is not
|
|
positive.
|
|
|
|
The crop and scale state is double-buffered state, and will be
|
|
applied on the next wl_surface.commit.
|
|
|
|
Arguments dst_x and dst_y do not exist here, use the x and y
|
|
arguments to wl_surface.attach. The x, y, dst_width, and dst_height
|
|
define the surface-local coordinate system irrespective of the
|
|
attached wl_buffer size.
|
|
</description>
|
|
|
|
<arg name="src_x" type="fixed" summary="source rectangle x"/>
|
|
<arg name="src_y" type="fixed" summary="source rectangle y"/>
|
|
<arg name="src_width" type="fixed" summary="source rectangle width"/>
|
|
<arg name="src_height" type="fixed" summary="source rectangle height"/>
|
|
<arg name="dst_width" type="int" summary="surface width"/>
|
|
<arg name="dst_height" type="int" summary="surface height"/>
|
|
</request>
|
|
|
|
<request name="set_source" since="2">
|
|
<description summary="set the source rectangle for cropping">
|
|
Set the source rectangle of the associated wl_surface. See
|
|
wl_viewport for the description, and relation to the wl_buffer
|
|
size.
|
|
|
|
If width is -1.0 and height is -1.0, the destination size is unset
|
|
instead. Any other pair of values for width and height that
|
|
contains zero or negative values raises the bad_value protocol
|
|
error.
|
|
|
|
The crop and scale state is double-buffered state, and will be
|
|
applied on the next wl_surface.commit.
|
|
</description>
|
|
|
|
<arg name="x" type="fixed" summary="source rectangle x"/>
|
|
<arg name="y" type="fixed" summary="source rectangle y"/>
|
|
<arg name="width" type="fixed" summary="source rectangle width"/>
|
|
<arg name="height" type="fixed" summary="source rectangle height"/>
|
|
</request>
|
|
|
|
<request name="set_destination" since="2">
|
|
<description summary="set the surface size for scaling">
|
|
Set the destination size of the associated wl_surface. See
|
|
wl_viewport for the description, and relation to the wl_buffer
|
|
size.
|
|
|
|
If width is -1 and height is -1, the destination size is unset
|
|
instead. Any other pair of values for width and height that
|
|
contains zero or negative values raises the bad_value protocol
|
|
error.
|
|
|
|
The crop and scale state is double-buffered state, and will be
|
|
applied on the next wl_surface.commit.
|
|
|
|
Arguments x and y do not exist here, use the x and y arguments to
|
|
wl_surface.attach. The x, y, width, and height define the
|
|
surface-local coordinate system irrespective of the attached
|
|
wl_buffer size.
|
|
</description>
|
|
|
|
<arg name="width" type="int" summary="surface width"/>
|
|
<arg name="height" type="int" summary="surface height"/>
|
|
</request>
|
|
</interface>
|
|
</protocol>
|