wayland: add wp-fractional-scale-v1 support

This protocol is pretty important since it finally lets us solve the
longstanding issue of fractional scaling in wayland (no more mpv doing
rendering over the target resolution and then being scaled down). This
protocol also can completely replace the buffer_scale usage that we are
currently using for integer scaling so hopefully this can be removed
sometime in the future. Note that vo_dmabuf_wayland is omitted because
we want the compositor to handle all the scaling for that VO (i.e. just
leave the default buffer scale of one). However, we are making viewport
required (everyone supports this anyway) with this commit so go ahead
and remove the redundant check in vo_dmabuf_wayland.

Fixes #9443.

generated/wayland/meson.build

@@ -2,6 +2,7 @@ wl_protocol_dir = wayland['deps'][2].get_variable(pkgconfig: 'pkgdatadir', inter
 protocols = [[wl_protocol_dir, 'stable/presentation-time/presentation-time.xml'],
              [wl_protocol_dir, 'stable/viewporter/viewporter.xml'],
              [wl_protocol_dir, 'stable/xdg-shell/xdg-shell.xml'],
+             [wl_protocol_dir, 'staging/fractional-scale/fractional-scale-v1.xml'], #TODO: guard this
              [wl_protocol_dir, 'unstable/idle-inhibit/idle-inhibit-unstable-v1.xml'],
              [wl_protocol_dir, 'unstable/linux-dmabuf/linux-dmabuf-unstable-v1.xml'],
              [wl_protocol_dir, 'unstable/xdg-decoration/xdg-decoration-unstable-v1.xml']]

video/out/opengl/context_wayland.c

@@ -76,14 +76,17 @@ static void resize(struct ra_ctx *ctx)
         egl_create_window(ctx);
 
     const int32_t width = wl->scaling * mp_rect_w(wl->geometry);
-    const int32_t height = wl->scaling * mp_rect_h(wl->geometry);
+    const int32_t height =wl->scaling * mp_rect_h(wl->geometry);
 
     vo_wayland_set_opaque_region(wl, ctx->opts.want_alpha);
     if (p->egl_window)
         wl_egl_window_resize(p->egl_window, width, height, 0, 0);
 
     wl->vo->dwidth  = width;
     wl->vo->dheight = height;
+
+    if (wl->fractional_viewport)
+        vo_wayland_handle_fractional_scale(wl);
 }
 
 static bool wayland_egl_check_visible(struct ra_ctx *ctx)

video/out/vo_dmabuf_wayland.c

@@ -336,13 +336,6 @@ static int preinit(struct vo *vo)
         return VO_ERROR;
     }
 
-    if (!vo->wl->viewport) {
-        MP_FATAL(vo->wl, "Compositor doesn't support the %s protocol!\n",
-                 wp_viewporter_interface.name);
-        return VO_ERROR;
-    }
-
-
     if (vo->wl->single_pixel_manager) {
 #if HAVE_WAYLAND_PROTOCOLS_1_27
         p->solid_buffer = wp_single_pixel_buffer_manager_v1_create_u32_rgba_buffer(

video/out/vo_wlshm.c

@@ -188,6 +188,10 @@ static int resize(struct vo *vo)
         p->free_buffers = buf->next;
         talloc_free(buf);
     }
+
+    if (wl->fractional_viewport)
+        vo_wayland_handle_fractional_scale(wl);
+
     return mp_sws_reinit(p->sws);
 }
 

video/out/vulkan/context_wayland.c

@@ -118,6 +118,10 @@ static bool resize(struct ra_ctx *ctx)
     const int32_t height = wl->scaling * mp_rect_h(wl->geometry);
 
     vo_wayland_set_opaque_region(wl, ctx->opts.want_alpha);
+
+    if (wl->fractional_viewport)
+        vo_wayland_handle_fractional_scale(wl);
+
     return ra_vk_ctx_resize(ctx, width, height);
 }
 

video/out/wayland_common.c

@@ -47,6 +47,9 @@
 #include "generated/wayland/single-pixel-buffer-v1.h"
 #endif
 
+//TODO: guard
+#include "generated/wayland/fractional-scale-v1.h"
+
 #if WAYLAND_VERSION_MAJOR > 1 || WAYLAND_VERSION_MINOR >= 20
 #define HAVE_WAYLAND_1_20
 #endif
@@ -171,7 +174,7 @@ static int spawn_cursor(struct vo_wayland_state *wl);
 static void greatest_common_divisor(struct vo_wayland_state *wl, int a, int b);
 static void remove_output(struct vo_wayland_output *out);
 static void request_decoration_mode(struct vo_wayland_state *wl, uint32_t mode);
-static void set_geometry(struct vo_wayland_state *wl);
+static void set_geometry(struct vo_wayland_state *wl, bool resize);
 static void set_surface_scaling(struct vo_wayland_state *wl);
 static void window_move(struct vo_wayland_state *wl, uint32_t serial);
 
@@ -676,7 +679,7 @@ static void output_handle_done(void *data, struct wl_output *wl_output)
     if (wl->current_output && wl->current_output->output == wl_output) {
         set_surface_scaling(wl);
         spawn_cursor(wl);
-        set_geometry(wl);
+        set_geometry(wl, false);
         wl->pending_vo_events |= VO_EVENT_DPI;
         wl->pending_vo_events |= VO_EVENT_RESIZE;
     }
@@ -750,14 +753,14 @@ static void surface_handle_enter(void *data, struct wl_surface *wl_surface,
     }
 
     if (!mp_rect_equals(&old_output_geometry, &wl->current_output->geometry)) {
-        set_geometry(wl);
+        set_geometry(wl, false);
         force_resize = true;
     }
 
     if (!mp_rect_equals(&old_geometry, &wl->geometry) || force_resize)
         wl->pending_vo_events |= VO_EVENT_RESIZE;
 
-    MP_VERBOSE(wl, "Surface entered output %s %s (0x%x), scale = %i, refresh rate = %f Hz\n",
+    MP_VERBOSE(wl, "Surface entered output %s %s (0x%x), scale = %f, refresh rate = %f Hz\n",
                o->make, o->model, o->id, wl->scaling, o->refresh_rate);
 
     wl->pending_vo_events |= VO_EVENT_WIN_STATE;
@@ -922,8 +925,8 @@ static void handle_toplevel_config(void *data, struct xdg_toplevel *toplevel,
 
 resize:
     MP_VERBOSE(wl, "Resizing due to xdg from %ix%i to %ix%i\n",
-               mp_rect_w(old_geometry)*wl->scaling, mp_rect_h(old_geometry)*wl->scaling,
-               mp_rect_w(wl->geometry)*wl->scaling, mp_rect_h(wl->geometry)*wl->scaling);
+               (int)round(mp_rect_w(old_geometry) * wl->scaling), (int)round(mp_rect_h(old_geometry) * wl->scaling),
+               (int)round(mp_rect_w(wl->geometry) * wl->scaling), (int)round(mp_rect_h(wl->geometry) * wl->scaling));
 
     wl->pending_vo_events |= VO_EVENT_RESIZE;
     wl->toplevel_configured = true;
@@ -953,6 +956,23 @@ static const struct xdg_toplevel_listener xdg_toplevel_listener = {
 #endif
 };
 
+//TODO: Guard
+static void preferred_scale(void *data,
+                            struct wp_fractional_scale_v1 *fractional_scale,
+                            uint32_t scale)
+{
+    struct vo_wayland_state *wl = data;
+    wl->scaling = (double)scale / 120;
+    MP_VERBOSE(wl, "Obtained preferred scale, %f, from the compositor.\n",
+               wl->scaling);
+    if (wl->current_output)
+        set_geometry(wl, true);
+}
+
+static const struct wp_fractional_scale_v1_listener fractional_scale_listener = {
+    preferred_scale,
+};
+
 static const char *zxdg_decoration_mode_to_str(const uint32_t mode)
 {
     switch (mode) {
@@ -1247,6 +1267,11 @@ static void registry_handle_add(void *data, struct wl_registry *reg, uint32_t id
     }
 #endif
 
+    //TODO: guard this
+    if (!strcmp(interface, wp_fractional_scale_manager_v1_interface.name) && found++) {
+        wl->fractional_scale_manager = wl_registry_bind(reg, id, &wp_fractional_scale_manager_v1_interface, 1);
+    }
+
     if (!strcmp(interface, wp_presentation_interface.name) && found++) {
         wl->presentation = wl_registry_bind(reg, id, &wp_presentation_interface, 1);
         wp_presentation_add_listener(wl->presentation, &pres_listener, wl);
@@ -1385,6 +1410,21 @@ static bool create_input(struct vo_wayland_state *wl)
     return 0;
 }
 
+static int create_viewports(struct vo_wayland_state *wl)
+{
+    if (wl->viewporter) {
+        wl->fractional_viewport = wp_viewporter_get_viewport(wl->viewporter, wl->surface);
+        wl->viewport = wp_viewporter_get_viewport(wl->viewporter, wl->surface);
+        wl->video_viewport = wp_viewporter_get_viewport(wl->viewporter, wl->video_surface);
+    }
+
+    if (!wl->viewporter || !wl->fractional_viewport || !wl->viewport || !wl->video_viewport) {
+        MP_ERR(wl, "failed to create viewport interfaces!\n");
+        return 1;
+    }
+    return 0;
+}
+
 static int create_xdg_surface(struct vo_wayland_state *wl)
 {
     wl->xdg_surface = xdg_wm_base_get_xdg_surface(wl->wm_base, wl->surface);
@@ -1393,8 +1433,10 @@ static int create_xdg_surface(struct vo_wayland_state *wl)
     wl->xdg_toplevel = xdg_surface_get_toplevel(wl->xdg_surface);
     xdg_toplevel_add_listener(wl->xdg_toplevel, &xdg_toplevel_listener, wl);
 
-    if (!wl->xdg_surface || !wl->xdg_toplevel)
+    if (!wl->xdg_surface || !wl->xdg_toplevel) {
+        MP_ERR(wl, "failled to create xdg_surface and xdg_toplevel!\n");
         return 1;
+    }
     return 0;
 }
 
@@ -1561,7 +1603,8 @@ static int set_cursor_visibility(struct vo_wayland_state *wl, bool on)
             return VO_FALSE;
         wl_pointer_set_cursor(wl->pointer, wl->pointer_id, wl->cursor_surface,
                               img->hotspot_x/wl->scaling, img->hotspot_y/wl->scaling);
-        wl_surface_set_buffer_scale(wl->cursor_surface, wl->scaling);
+        if (!wl->fractional_scale_manager)
+            wl_surface_set_buffer_scale(wl->cursor_surface, wl->scaling);
         wl_surface_attach(wl->cursor_surface, buffer, 0, 0);
         wl_surface_damage_buffer(wl->cursor_surface, 0, 0, img->width, img->height);
         wl_surface_commit(wl->cursor_surface);
@@ -1571,14 +1614,14 @@ static int set_cursor_visibility(struct vo_wayland_state *wl, bool on)
     return VO_TRUE;
 }
 
-static void set_geometry(struct vo_wayland_state *wl)
+static void set_geometry(struct vo_wayland_state *wl, bool resize)
 {
     struct vo *vo = wl->vo;
     assert(wl->current_output);
 
     struct vo_win_geometry geo;
     struct mp_rect screenrc = wl->current_output->geometry;
-    vo_calc_window_geometry(vo, &screenrc, &geo);
+    vo_calc_window_geometry2(vo, &screenrc, wl->scaling, &geo);
     vo_apply_window_geometry(vo, &geo);
 
     greatest_common_divisor(wl, vo->dwidth, vo->dheight);
@@ -1587,8 +1630,15 @@ static void set_geometry(struct vo_wayland_state *wl)
 
     wl->vdparams.x0 = 0;
     wl->vdparams.y0 = 0;
-    wl->vdparams.x1 = vo->dwidth / wl->scaling;
-    wl->vdparams.y1 = vo->dheight / wl->scaling;
+    wl->vdparams.x1 = round(vo->dwidth / wl->scaling);
+    wl->vdparams.y1 = round(vo->dheight / wl->scaling);
+
+    if (resize) {
+        wl->window_size = wl->vdparams;
+        if (!wl->vo_opts->fullscreen && !wl->vo_opts->window_maximized)
+            wl->geometry = wl->window_size;
+        wl->pending_vo_events |= VO_EVENT_RESIZE;
+    }
 }
 
 static int set_screensaver_inhibitor(struct vo_wayland_state *wl, int state)
@@ -1612,19 +1662,21 @@ static int set_screensaver_inhibitor(struct vo_wayland_state *wl, int state)
 static void set_surface_scaling(struct vo_wayland_state *wl)
 {
     bool dmabuf_wayland = !strcmp(wl->vo->driver->name, "dmabuf-wayland");
-    int old_scale = wl->scaling;
-    if (wl->vo_opts->hidpi_window_scale && !dmabuf_wayland) {
+    double old_scale = wl->scaling;
+    if (wl->vo_opts->hidpi_window_scale && !dmabuf_wayland && !wl->fractional_scale_manager) {
         wl->scaling = wl->current_output->scale;
     } else {
         wl->scaling = 1;
     }
 
-    double factor = (double)old_scale / wl->scaling;
-    wl->vdparams.x1 *= factor;
-    wl->vdparams.y1 *= factor;
-    wl->window_size.x1 *= factor;
-    wl->window_size.y1 *= factor;
-    wl_surface_set_buffer_scale(wl->surface, wl->scaling);
+    if (!wl->fractional_scale_manager) {
+        double factor = old_scale / wl->scaling;
+        wl->vdparams.x1 *= factor;
+        wl->vdparams.y1 *= factor;
+        wl->window_size.x1 *= factor;
+        wl->window_size.y1 *= factor;
+        wl_surface_set_buffer_scale(wl->surface, wl->scaling);
+    }
 }
 
 static void set_window_bounds(struct vo_wayland_state *wl)
@@ -1845,13 +1897,8 @@ int vo_wayland_control(struct vo *vo, int *events, int request, void *arg)
             if (opt == &opts->geometry || opt == &opts->autofit ||
                 opt == &opts->autofit_smaller || opt == &opts->autofit_larger)
             {
-                if (wl->current_output) {
-                    set_geometry(wl);
-                    wl->window_size = wl->vdparams;
-                    if (!wl->vo_opts->fullscreen && !wl->vo_opts->window_maximized)
-                        wl->geometry = wl->window_size;
-                    wl->pending_vo_events |= VO_EVENT_RESIZE;
-                }
+                if (wl->current_output)
+                    set_geometry(wl, true);
             }
         }
         return VO_TRUE;
@@ -1935,6 +1982,12 @@ int vo_wayland_control(struct vo *vo, int *events, int request, void *arg)
     return VO_NOTIMPL;
 }
 
+void vo_wayland_handle_fractional_scale(struct vo_wayland_state *wl)
+{
+    wp_viewport_set_destination(wl->fractional_viewport, mp_rect_w(wl->geometry),
+                                mp_rect_h(wl->geometry));
+}
+
 int vo_wayland_init(struct vo *vo)
 {
     vo->wl = talloc_zero(NULL, struct vo_wayland_state);
@@ -1988,6 +2041,9 @@ int vo_wayland_init(struct vo *vo)
     }
 
     /* Can't be initialized during registry due to multi-protocol dependence */
+    if (create_viewports(wl))
+        return false;
+
     if (create_xdg_surface(wl))
         return false;
 
@@ -1996,11 +2052,6 @@ int vo_wayland_init(struct vo *vo)
         wl_subsurface_set_desync(wl->video_subsurface);
     }
 
-    if (wl->viewporter) {
-        wl->viewport = wp_viewporter_get_viewport(wl->viewporter, wl->surface);
-        wl->video_viewport = wp_viewporter_get_viewport(wl->viewporter, wl->video_surface);
-    }
-
     const char *xdg_current_desktop = getenv("XDG_CURRENT_DESKTOP");
     if (xdg_current_desktop != NULL && strstr(xdg_current_desktop, "GNOME"))
         MP_WARN(wl, "GNOME's wayland compositor lacks support for the idle inhibit protocol. This means the screen can blank during playback.\n");
@@ -2019,6 +2070,15 @@ int vo_wayland_init(struct vo *vo)
     }
 #endif
 
+    //TODO: guard
+    if (wl->fractional_scale_manager) {
+        wl->fractional_scale = wp_fractional_scale_manager_v1_get_fractional_scale(wl->fractional_scale_manager, wl->surface);
+        wp_fractional_scale_v1_add_listener(wl->fractional_scale, &fractional_scale_listener, wl);
+    } else {
+        MP_VERBOSE(wl, "Compositor doesn't support the %s protocol!\n",
+                   wp_fractional_scale_manager_v1_interface.name);
+    }
+
     if (wl->dnd_devman && wl->seat) {
         wl->dnd_ddev = wl_data_device_manager_get_data_device(wl->dnd_devman, wl->seat);
         wl_data_device_add_listener(wl->dnd_ddev, &data_device_listener, wl);
@@ -2084,7 +2144,7 @@ int vo_wayland_reconfig(struct vo *vo)
         wl->pending_vo_events |= VO_EVENT_DPI;
     }
 
-    set_geometry(wl);
+    set_geometry(wl, false);
     wl->window_size = wl->vdparams;
 
     if (wl->opts->configure_bounds)
@@ -2194,6 +2254,13 @@ void vo_wayland_uninit(struct vo *vo)
     if (wl->frame_callback)
         wl_callback_destroy(wl->frame_callback);
 
+    //TODO: guard these
+    if (wl->fractional_scale)
+        wp_fractional_scale_v1_destroy(wl->fractional_scale);
+
+    if (wl->fractional_scale_manager)
+        wp_fractional_scale_manager_v1_destroy(wl->fractional_scale_manager);
+
     if (wl->idle_inhibitor)
         zwp_idle_inhibitor_v1_destroy(wl->idle_inhibitor);
 
@@ -2215,6 +2282,9 @@ void vo_wayland_uninit(struct vo *vo)
     if (wl->viewporter)
         wp_viewporter_destroy(wl->viewporter);
 
+    if (wl->fractional_viewport)
+        wp_viewport_destroy(wl->fractional_viewport);
+
     if (wl->viewport)
         wp_viewport_destroy(wl->viewport);
 

video/out/wayland_common.h

@@ -74,7 +74,7 @@ struct vo_wayland_state {
     int mouse_x;
     int mouse_y;
     int pending_vo_events;
-    int scaling;
+    double scaling;
     int timeout_count;
     int wakeup_pipe[2];
 
@@ -84,6 +84,10 @@ struct vo_wayland_state {
     void *content_type;
     int current_content_type;
 
+    /* fractional-scale */
+    void *fractional_scale_manager;
+    void *fractional_scale;
+
     /* idle-inhibit */
     struct zwp_idle_inhibit_manager_v1 *idle_inhibit_manager;
     struct zwp_idle_inhibitor_v1 *idle_inhibitor;
@@ -122,6 +126,7 @@ struct vo_wayland_state {
 
     /* viewporter */
     struct wp_viewporter *viewporter;
+    struct wp_viewport   *fractional_viewport;
     struct wp_viewport   *viewport;
     struct wp_viewport   *video_viewport;
 
@@ -161,6 +166,7 @@ int vo_wayland_control(struct vo *vo, int *events, int request, void *arg);
 int vo_wayland_init(struct vo *vo);
 int vo_wayland_reconfig(struct vo *vo);
 
+void vo_wayland_handle_fractional_scale(struct vo_wayland_state *wl);
 void vo_wayland_set_opaque_region(struct vo_wayland_state *wl, int alpha);
 void vo_wayland_sync_swap(struct vo_wayland_state *wl);
 void vo_wayland_uninit(struct vo *vo);