Merge pull request WayfireWM#9 from WayfireWM/background-view

Add background view plugin

metadata/background-view.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0"?>
+<wayfire>
+	<plugin name="background-view">
+	<_short>Background View</_short>
+	<category>Desktop</category>
+	<option name="command" type="string">
+		<_short>Command</_short>
+		<default>mpv --loop=inf</default>
+	</option>
+	<option name="file" type="string">
+		<_short>File</_short>
+		<hint>file</hint>
+		<default></default>
+	</option>
+	</plugin>
+</wayfire>

metadata/meson.build

@@ -1,2 +1,3 @@
 install_data('autorotate-iio.xml', install_dir: wayfire.get_variable(pkgconfig: 'metadatadir'))
+install_data('background-view.xml', install_dir: wayfire.get_variable(pkgconfig: 'metadatadir'))
 install_data('join-views.xml', install_dir: wayfire.get_variable(pkgconfig: 'metadatadir'))

src/background-view.cpp

@@ -0,0 +1,169 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 Scott Moreau
+ *
+ * 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 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.
+ */
+
+#include <signal.h>
+#include <wayfire/core.hpp>
+#include <wayfire/view.hpp>
+#include <wayfire/plugin.hpp>
+#include <wayfire/output.hpp>
+#include <wayfire/signal-definitions.hpp>
+#include <wayfire/workspace-manager.hpp>
+#include <wayfire/output-layout.hpp>
+
+extern "C"
+{
+#include <wlr/config.h>
+#if WLR_HAS_XWAYLAND
+#define class class_t
+#define static
+#include <wlr/xwayland.h>
+#undef static
+#undef class
+#endif
+}
+
+struct process
+{
+    nonstd::observer_ptr<wf::view_interface_t> view;
+    pid_t pid;
+};
+
+static std::map<wf::output_t *, struct process> procs;
+
+class wayfire_background_view : public wf::plugin_interface_t
+{
+    const std::string transformer_name = "background-view";
+    /* The command option should be set to a client like mpv, projectM or
+     * a single xscreensaver.
+     */
+    wf::option_wrapper_t<std::string> command{"background-view/command"};
+    /* The file option is for convenience when using wcm. If file is set,
+     * it will be appended to the command, wrapped in double quotes.
+     */
+    wf::option_wrapper_t<std::string> file{"background-view/file"};
+
+    public:
+    void init() override
+    {
+        grab_interface->name = transformer_name;
+        grab_interface->capabilities = 0;
+
+        command.set_callback(option_changed);
+        file.set_callback(option_changed);
+
+        output->connect_signal("map-view", &view_mapped);
+
+        option_changed();
+    }
+
+    wf::config::option_base_t::updated_callback_t option_changed = [=] ()
+    {
+        if (procs[output].view)
+        {
+            procs[output].view->close();
+            kill(procs[output].pid, SIGINT);
+        }
+
+        procs[output].view = nullptr;
+        procs[output].pid = wf::get_core().run(std::string(command) + add_arg_if_not_empty(file));
+    };
+
+    wf::signal_connection_t view_mapped{[this] (wf::signal_data_t *data)
+    {
+        auto view = get_signaled_view(data);
+#if WLR_HAS_XWAYLAND
+        wlr_surface *wlr_surface = view->get_wlr_surface();
+        bool is_xwayland_surface = wlr_surface_is_xwayland_surface(wlr_surface);
+#endif
+        /* Get pid for view */
+        pid_t view_pid;
+        wl_client_get_credentials(view->get_client(), &view_pid, 0, 0);
+
+        for (auto& o : wf::get_core().output_layout->get_outputs())
+        {
+            /* This condition attempts to match the pid that we got from run()
+             * to the client pid. This will not work in all cases. Naturally,
+             * not every command will spawn a view. This wont work well for gtk
+             * apps because it has a system where the client will defer to an
+             * existing instance with the same app-id and have that instance
+             * spawn a new view but have the same pid, meaning when we compare
+             * the pids, they wont match unless we happen to be the first to run
+             * the app. This does work well with clients such as mpv, projectM
+             * and running xscreensavers directly.
+             */
+            if (procs[o].pid == view_pid
+#if WLR_HAS_XWAYLAND
+                || (is_xwayland_surface &&
+                /* For this match to work, the client must set _NET_WM_PID */
+                procs[o].pid == wlr_xwayland_surface_from_wlr_surface(wlr_surface)->pid)
+#endif
+                )
+            {
+                view->set_decoration(nullptr);
+
+                /* Move to the respective output */
+                wf::get_core().move_view_to_output(view, o);
+
+                /* A client should be used that can be resized to any size.
+                 * If we set it fullscreen, the screensaver would be inhibited
+                 * so we send a resize request that is the size of the output
+                 */
+                view->set_geometry(o->get_relative_geometry());
+
+                /* Set it as the background */
+                o->workspace->add_view(view, wf::LAYER_BACKGROUND);
+
+                /* Make it show on all workspaces */
+                view->role = wf::VIEW_ROLE_DESKTOP_ENVIRONMENT;
+
+                procs[o].view = view;
+
+                break;
+            }
+        }
+    }};
+
+    std::string add_arg_if_not_empty(std::string in)
+    {
+        if (!in.empty())
+        {
+            return " \"" + in + "\"";
+        }
+        else
+        {
+            return in;
+        }
+    }
+
+    void fini() override
+    {
+        if (procs[output].view)
+        {
+            procs[output].view->close();
+            kill(procs[output].pid, SIGINT);
+        }
+    }
+};
+
+DECLARE_WAYFIRE_PLUGIN(wayfire_background_view);

src/meson.build

@@ -2,6 +2,10 @@ autorotate = shared_module('autorotate-iio', 'autorotate-iio.cpp',
     dependencies: [wayfire, wlroots, wfconfig, giomm],
     install: true, install_dir: join_paths(get_option('libdir'), 'wayfire'))
 
+background_view = shared_module('background-view', 'background-view.cpp',
+    dependencies: [wayfire, wlroots, wfconfig],
+    install: true, install_dir: join_paths(get_option('libdir'), 'wayfire'))
+
 joinviews = shared_module('join-views', 'join-views.cpp',
     dependencies: [wayfire, wlroots, wfconfig],
     install: true, install_dir: join_paths(get_option('libdir'), 'wayfire'))