deco: refactor button code

- Make the height+width of buttons the same as the title bar.
- Center icons within the 'button space'
- Show button background color on hover (just hard-coded grey for now)

src/cursor.c

@@ -90,9 +90,7 @@ static void process_cursor_motion(struct server *server, uint32_t time)
 
 	/* TODO: Could we use wlr_xcursor_get_resize_name() here?? */
 	switch (view_area) {
-	case LAB_DECO_PART_TITLE:
+	case LAB_DECO_NONE:
-		wlr_xcursor_manager_set_cursor_image(
-			server->cursor_mgr, XCURSOR_DEFAULT, server->cursor);
 		break;
 	case LAB_DECO_PART_TOP:
 		wlr_xcursor_manager_set_cursor_image(
@@ -110,6 +108,10 @@ static void process_cursor_motion(struct server *server, uint32_t time)
 		wlr_xcursor_manager_set_cursor_image(
 			server->cursor_mgr, "left_side", server->cursor);
 		break;
+	default:
+		wlr_xcursor_manager_set_cursor_image(
+			server->cursor_mgr, XCURSOR_DEFAULT, server->cursor);
+		break;
 	}
 	if (surface) {
 		bool focus_changed = seat->pointer_state.focused_surface !=

src/deco.c

@@ -37,31 +37,26 @@ struct wlr_box deco_max_extents(struct view *view)
 
 struct wlr_box deco_box(struct view *view, enum deco_part deco_part)
 {
-	int margin;
-
 	struct wlr_box box = { .x = 0, .y = 0, .width = 0, .height = 0 };
 	BUG_ON(!view);
 	switch (deco_part) {
 	case LAB_DECO_BUTTON_CLOSE:
-		wlr_texture_get_size(theme.xbm_close_active_unpressed,
+		box.width = rc.title_height;
-				     &box.width, &box.height);
+		box.height = rc.title_height;
-		margin = (rc.title_height - box.height) / 2;
+		box.x = view->x + view->w - rc.title_height;
-		box.x = view->x + view->w + margin - rc.title_height;
+		box.y = view->y - rc.title_height;
-		box.y = view->y - rc.title_height + margin;
 		break;
 	case LAB_DECO_BUTTON_MAXIMIZE:
-		wlr_texture_get_size(theme.xbm_maximize_active_unpressed,
+		box.width = rc.title_height;
-				     &box.width, &box.height);
+		box.height = rc.title_height;
-		margin = (rc.title_height - box.height) / 2;
+		box.x = view->x + view->w - rc.title_height * 2;
-		box.x = view->x + view->w + margin - rc.title_height * 2;
+		box.y = view->y - rc.title_height;
-		box.y = view->y - rc.title_height + margin;
 		break;
 	case LAB_DECO_BUTTON_ICONIFY:
-		wlr_texture_get_size(theme.xbm_iconify_active_unpressed,
+		box.width = rc.title_height;
-				     &box.width, &box.height);
+		box.height = rc.title_height;
-		margin = (rc.title_height - box.height) / 2;
+		box.x = view->x + view->w - rc.title_height * 3;
-		box.x = view->x + view->w + margin - rc.title_height * 3;
+		box.y = view->y - rc.title_height;
-		box.y = view->y - rc.title_height + margin;
 		break;
 	case LAB_DECO_PART_TITLE:
 		box.x = view->x;

src/output.c

@@ -79,11 +79,35 @@ static void render_icon(struct draw_data *d, struct wlr_box box,
 	if (!texture)
 		return;
 	float matrix[9];
-	wlr_matrix_project_box(matrix, &box, WL_OUTPUT_TRANSFORM_NORMAL, 0,
+
+	/* centre-align icon if smaller than designated box */
+	struct wlr_box button;
+	wlr_texture_get_size(texture, &button.width, &button.height);
+	if (box.width > button.width) {
+		button.x = box.x + (box.width - button.width) / 2;
+	} else {
+		button.x = box.x;
+		button.width = box.width;
+	}
+	if (box.height > button.height) {
+		button.y = box.y + (box.height - button.height) / 2;
+	} else {
+		button.y = box.y;
+		button.height = box.height;
+	}
+
+	wlr_matrix_project_box(matrix, &button, WL_OUTPUT_TRANSFORM_NORMAL, 0,
 			       d->transform_matrix);
 	wlr_render_texture_with_matrix(d->renderer, texture, matrix, 1);
 }
 
+static bool isbutton(enum deco_part deco_part)
+{
+	return deco_part == LAB_DECO_BUTTON_CLOSE ||
+	       deco_part == LAB_DECO_BUTTON_MAXIMIZE ||
+	       deco_part == LAB_DECO_BUTTON_ICONIFY;
+}
+
 static void render_decorations(struct wlr_output *output, struct view *view)
 {
 	if (!view->server_side_deco)
@@ -93,18 +117,32 @@ static void render_decorations(struct wlr_output *output, struct view *view)
 		.transform_matrix = output->transform_matrix,
 	};
 
+	/* border */
 	ddata.rgba = theme.window_active_handle_bg_color;
 	draw_rect(&ddata, deco_box(view, LAB_DECO_PART_TOP));
 	draw_rect(&ddata, deco_box(view, LAB_DECO_PART_RIGHT));
 	draw_rect(&ddata, deco_box(view, LAB_DECO_PART_BOTTOM));
 	draw_rect(&ddata, deco_box(view, LAB_DECO_PART_LEFT));
 
+	/* title */
 	if (view->surface == seat_focused_surface())
 		ddata.rgba = theme.window_active_title_bg_color;
 	else
 		ddata.rgba = theme.window_inactive_title_bg_color;
 	draw_rect(&ddata, deco_box(view, LAB_DECO_PART_TITLE));
 
+	/* button background */
+	struct wlr_cursor *cur = view->server->cursor;
+	enum deco_part deco_part = deco_at(view, cur->x, cur->y);
+
+	struct wlr_box box = deco_box(view, deco_part);
+	if (isbutton(deco_part) &&
+	    wlr_box_contains_point(&box, cur->x, cur->y)) {
+		ddata.rgba = (float[4]){ 0.5, 0.5, 0.5, 0.5 };
+		draw_rect(&ddata, deco_box(view, deco_part));
+	}
+
+	/* buttons */
 	if (view->surface == seat_focused_surface()) {
 		render_icon(&ddata, deco_box(view, LAB_DECO_BUTTON_CLOSE),
 			    theme.xbm_close_active_unpressed);