[PATCH wayland-protocols 1/2] stable: add viewporter draft
Yong Bakos
junk at humanoriented.com
Mon Apr 18 12:15:28 UTC 2016
On Apr 15, 2016, at 9:53 AM, Pekka Paalanen <ppaalanen at gmail.com> wrote:
>
> From: Pekka Paalanen <pekka.paalanen at collabora.co.uk>
>
> This XML file has been copied verbatim from Weston 1.10.0 release,
> protocol/scaler.xml.
>
> The interfaces still need renaming according to wayland-protocols
> policy. Also a redundant request needs to be removed. These will be done
> in a follow-up patch to clearly show the changes.
>
> Signed-off-by: Pekka Paalanen <pekka.paalanen at collabora.co.uk>
There's one paragraph I think could use a rewriting, noted inline below,
but since this is just a move, the writing and such is
Reviewed-by: Yong Bakos <ybakos at humanoriented.com>
yong
> ---
> stable/viewporter/README | 7 ++
> stable/viewporter/viewporter.xml | 208 +++++++++++++++++++++++++++++++++++++++
> 2 files changed, 215 insertions(+)
> create mode 100644 stable/viewporter/README
> create mode 100644 stable/viewporter/viewporter.xml
>
> diff --git a/stable/viewporter/README b/stable/viewporter/README
> new file mode 100644
> index 0000000..e09057b
> --- /dev/null
> +++ b/stable/viewporter/README
> @@ -0,0 +1,7 @@
> +Viewporter: cropping and scaling extension for surface contents
> +
> +Previously known as wl_scaler.
> +
> +Maintainers:
> +Pekka Paalanen <pekka.paalanen at collabora.co.uk>
> +
> diff --git a/stable/viewporter/viewporter.xml b/stable/viewporter/viewporter.xml
> new file mode 100644
> index 0000000..0e482a6
> --- /dev/null
> +++ b/stable/viewporter/viewporter.xml
> @@ -0,0 +1,208 @@
> +<?xml version="1.0" encoding="UTF-8"?>
> +<protocol name="scaler">
> +
> + <copyright>
> + Copyright © 2013-2014 Collabora, Ltd.
> +
> + Permission is hereby granted, free of charge, to any person obtaining a
> + copy of this software and associated documentation files (the "Software"),
> + to deal in the Software without restriction, including without limitation
> + the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + and/or sell copies of the Software, and to permit persons to whom the
> + Software is furnished to do so, subject to the following conditions:
> +
> + The above copyright notice and this permission notice (including the next
> + paragraph) shall be included in all copies or substantial portions of the
> + Software.
> +
> + THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
> + THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> + FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
> + DEALINGS IN THE 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 first sentence of this paragraph is a bit cumbersome. Maybe:
This interface defines a source rectangle of the wl_buffer
contents (src_x, src_y, src_width, src_height), and a means of
scaling the source rectangle to a destination size (dst_width,
dst_height).
> +
> + 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 source rectangle 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>
> --
> 2.7.3
>
> _______________________________________________
> wayland-devel mailing list
> wayland-devel at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/wayland-devel
More information about the wayland-devel
mailing list