widgets: export extents() function

This commit adds a function called extents() to widgets. In the case of
a systray, it takes the systray's screen as its argument to correctly
calculate the width. By default, 1 is assumed. For all other widgets,
the argument can be ommitted.
The function doesn't return the geometry as drawn, instead it returns
the geometry the widget _wants_ to be drawn at, for example an imagebox
always has (image width, image height) as the return values even if it's
drawn with a smaller width and height on a smaller wibox.

Signed-off-by: Gregor Best <farhaven@googlemail.com>
Signed-off-by: Julien Danjou <julien@danjou.info>

widget.c

@@ -495,6 +495,29 @@ luaA_widget_newindex(lua_State *L)
     return 0;
 }
 
+static int
+luaA_widget_extents(lua_State *L)
+{
+    widget_t *widget = luaL_checkudata(L, 1, "widget");
+    area_t g = {
+        .x = 0,
+        .y = 0,
+        .width = 0,
+        .height = 0
+    };
+
+    if(widget->extents)
+        g = widget->extents(L, widget);
+
+    lua_newtable(L);
+    lua_pushnumber(L, g.width);
+    lua_setfield(L, -2, "width");
+    lua_pushnumber(L, g.height);
+    lua_setfield(L, -2, "height");
+
+    return 1;
+}
+
 const struct luaL_reg awesome_widget_methods[] =
 {
     { "__call", luaA_widget_new },
@@ -503,6 +526,7 @@ const struct luaL_reg awesome_widget_methods[] =
 const struct luaL_reg awesome_widget_meta[] =
 {
     { "buttons", luaA_widget_buttons },
+    { "extents", luaA_widget_extents },
     { "__index", luaA_widget_index },
     { "__newindex", luaA_widget_newindex },
     { "__gc", luaA_widget_gc },

widget.h

@@ -37,8 +37,10 @@ struct widget_t
     widget_constructor_t *type;
     /** Widget destructor */
     widget_destructor_t *destructor;
-    /** Geometry function */
+    /** Geometry function for drawing */
     area_t (*geometry)(widget_t *, screen_t *, int, int);
+    /** Extents function */
+    area_t (*extents)(lua_State *, widget_t *);
     /** Draw function */
     void (*draw)(widget_t *, draw_context_t *, area_t, wibox_t *);
     /** Index function */

widgets/graph.c

@@ -160,6 +160,16 @@ graph_geometry(widget_t *widget, screen_t *screen, int height, int width)
     return geometry;
 }
 
+static area_t
+graph_extents(lua_State *L, widget_t *widget)
+{
+    area_t geometry;
+    graph_data_t *d = widget->data;
+    geometry.width = geometry.height = d->width;
+
+    return geometry;
+}
+
 /** Draw a graph widget.
  * \param ctx The draw context.
  * \param w The widget node we are called from.
@@ -595,6 +605,7 @@ widget_graph(widget_t *w)
     w->newindex = luaA_graph_newindex;
     w->destructor = graph_destructor;
     w->geometry = graph_geometry;
+    w->extents = graph_extents;
 
     graph_data_t *d = w->data = p_new(graph_data_t, 1);
 

widgets/imagebox.c

@@ -76,6 +76,26 @@ imagebox_geometry(widget_t *widget, screen_t *screen, int height, int width)
     return geometry;
 }
 
+static area_t
+imagebox_extents(lua_State *L, widget_t *widget)
+{
+    area_t geometry = {
+        .x = 0,
+        .y = 0,
+        .width = 0,
+        .height = 0
+    };
+    imagebox_data_t *d = widget->data;
+
+    if(d->image)
+    {
+        geometry.width = image_getwidth(d->image);
+        geometry.height = image_getheight(d->image);
+    }
+
+    return geometry;
+}
+
 /** Draw an image.
  * \param widget The widget.
  * \param ctx The draw context.
@@ -215,6 +235,7 @@ widget_imagebox(widget_t *w)
     w->newindex = luaA_imagebox_newindex;
     w->destructor = imagebox_destructor;
     w->geometry = imagebox_geometry;
+    w->extents = imagebox_extents;
     w->data = d = p_new(imagebox_data_t, 1);
     d->resize = true;
     d->valign = AlignTop;

widgets/progressbar.c

@@ -163,6 +163,34 @@ progressbar_geometry(widget_t *widget, screen_t *screen, int height, int width)
     return geometry;
 }
 
+static area_t
+progressbar_extents(lua_State *L, widget_t *widget)
+{
+    area_t geometry;
+    progressbar_data_t *d = widget->data;
+
+    if (d->vertical)
+    {
+        int pb_width = (int) ((d->width - 2 * (d->border_width + d->border_padding) * d->bars.len
+                       - d->gap * (d->bars.len - 1)) / d->bars.len);
+        geometry.width = d->bars.len * (pb_width + 2 * (d->border_width + d->border_padding)
+                         + d->gap) - d->gap;
+    }else
+    {
+        int pb_width = d->width - 2 * (d->border_width + d->border_padding);
+        if(d->ticks_count && d->ticks_gap)
+        {
+            int unit = (pb_width + d->ticks_gap) / d->ticks_count;
+            pb_width = unit * d->ticks_count - d->ticks_gap; /* rounded to match ticks... */
+        }
+        geometry.width = pb_width + 2 * (d->border_width + d->border_padding);
+    }
+
+    geometry.height = geometry.width;
+
+    return geometry;
+}
+
 /** Draw a progressbar.
  * \param ctx The draw context.
  * \param w The widget node we're drawing for.
@@ -650,6 +678,7 @@ widget_progressbar(widget_t *w)
     w->newindex = luaA_progressbar_newindex;
     w->destructor = progressbar_destructor;
     w->geometry = progressbar_geometry;
+    w->extents = progressbar_extents;
 
     progressbar_data_t *d = w->data = p_new(progressbar_data_t, 1);
 

widgets/systray.c

@@ -50,6 +50,33 @@ systray_geometry(widget_t *widget, screen_t *screen, int height, int width)
     return geometry;
 }
 
+static area_t
+systray_extents(lua_State *L, widget_t *widget)
+{
+    area_t geometry;
+    int screen = screen_virttophys(luaL_optnumber(L, -1, 1)), n = 0;
+
+    geometry.height = 0;
+    int width = 0;
+
+    for(int i = 0; i < globalconf.embedded.len; i++)
+        if(globalconf.embedded.tab[i].phys_screen == screen)
+        {
+            xcb_get_geometry_cookie_t geo = xcb_get_geometry(globalconf.connection, globalconf.embedded.tab[i].win);
+            xcb_get_geometry_reply_t *g = xcb_get_geometry_reply(globalconf.connection, geo, NULL);
+
+            n++;
+            if(g->height > geometry.height)
+                geometry.height = g->height;
+            if(g->width > width)
+                width = g->width;
+        }
+
+    geometry.width = width * n;
+
+    return geometry;
+}
+
 static void
 systray_draw(widget_t *widget, draw_context_t *ctx,
              area_t geometry, wibox_t *p)
@@ -83,6 +110,7 @@ widget_systray(widget_t *w)
 {
     w->draw = systray_draw;
     w->geometry = systray_geometry;
+    w->extents = systray_extents;
 
     return w;
 }

widgets/textbox.c

@@ -79,6 +79,32 @@ textbox_geometry(widget_t *widget, screen_t *screen, int height, int width)
     return geometry;
 }
 
+static area_t
+textbox_extents(lua_State *L, widget_t *widget)
+{
+    textbox_data_t *d = widget->data;
+    area_t geometry = d->extents;
+
+    geometry.width += d->margin.left + d->margin.left;
+    geometry.height += d->margin.bottom + d->margin.top;
+
+    if(d->bg_image)
+    {
+        int bgi_height = image_getheight(d->bg_image);
+        int bgi_width = image_getwidth(d->bg_image);
+        double ratio = d->bg_resize ? (double) geometry.height / bgi_height : 1;
+        geometry.width = MAX(d->extents.width + d->margin.left + d->margin.right, MAX(d->width, bgi_width * ratio));
+    }
+
+    if (d->data.len == 0)
+    {
+        geometry.width = 0;
+        geometry.height = 0;
+    }
+
+    return geometry;
+}
+
 /** Draw a textbox widget.
  * \param widget The widget.
  * \param ctx The draw context.
@@ -376,6 +402,7 @@ widget_textbox(widget_t *w)
     w->newindex = luaA_textbox_newindex;
     w->destructor = textbox_destructor;
     w->geometry = textbox_geometry;
+    w->extents = textbox_extents;
 
     textbox_data_t *d = w->data = p_new(textbox_data_t, 1);
     d->ellip = PANGO_ELLIPSIZE_END;