Fix T62016: Outliner visibility icons drag behaviour broken

We are mixing bool and fancy 3-in-1 func-set buttons in the outliner.
So they would return different pushed state in
ui_drag_toggle_but_pushed_state().

We now have a callback function that allows the button to set its own
pushed_button_state callback function.

Note: This is a bit of overkill since we are planning to change the
3-in-1 outliner buttons. That said, it may be nice to have, since in the
future we can mix those buttons for other things.

Reviewers: brecht

Differential Revision: https://developer.blender.org/D4434

source/blender/editors/include/UI_interface.h

@@ -438,6 +438,7 @@ typedef struct ARegion *(*uiButSearchCreateFunc)(struct bContext *C, struct AReg
 typedef void (*uiButSearchFunc)(const struct bContext *C, void *arg, const char *str, uiSearchItems *items);
 /* Must return allocated string. */
 typedef char *(*uiButToolTipFunc)(struct bContext *C, void *argN, const char *tip);
+typedef int (*uiButPushedStateFunc)(struct bContext *C, void *arg);
 
 typedef void (*uiBlockHandleFunc)(struct bContext *C, void *arg, int event);
 
@@ -880,6 +881,8 @@ void UI_but_focus_on_enter_event(struct wmWindow *win, uiBut *but);
 
 void UI_but_func_hold_set(uiBut *but, uiButHandleHoldFunc func, void *argN);
 
+void UI_but_func_pushed_state_set(uiBut *but, uiButPushedStateFunc func, void *arg);
+
 /* Autocomplete
  *
  * Tab complete helper functions, for use in uiButCompleteFunc callbacks.

source/blender/editors/interface/interface.c

@@ -4456,6 +4456,12 @@ void UI_but_func_tooltip_set(uiBut *but, uiButToolTipFunc func, void *argN)
 	but->tip_argN = argN;
 }
 
+void UI_but_func_pushed_state_set(uiBut *but, uiButPushedStateFunc func, void *arg)
+{
+	but->pushed_state_func = func;
+	but->pushed_state_arg = arg;
+}
+
 uiBut *uiDefBlockBut(uiBlock *block, uiBlockCreateFunc func, void *arg, const char *str, int x, int y, short width, short height, const char *tip)
 {
 	uiBut *but = ui_def_but(block, UI_BTYPE_BLOCK, 0, str, x, y, width, height, arg, 0.0, 0.0, 0.0, 0.0, tip);

source/blender/editors/interface/interface_handlers.c

@@ -1240,13 +1240,18 @@ static bool ui_drag_toggle_but_is_supported(const uiBut *but)
 
 /* Button pushed state to compare if other buttons match. Can be more
  * then just true or false for toggle buttons with more than 2 states. */
-static int ui_drag_toggle_but_pushed_state(uiBut *but)
+static int ui_drag_toggle_but_pushed_state(bContext *C, uiBut *but)
 {
 	if (but->rnapoin.data == NULL && but->poin == NULL && but->icon) {
-		/* Assume icon identifies a unique state, for buttons that
-		 * work though functions callbacks and don't have an boolean
-		 * value that indicates the state. */
-		return but->icon + but->iconadd;
+		if (but->pushed_state_func) {
+			return but->pushed_state_func(C, but->pushed_state_arg);
+		}
+		else {
+			/* Assume icon identifies a unique state, for buttons that
+			* work though functions callbacks and don't have an boolean
+			* value that indicates the state. */
+			return but->icon + but->iconadd;
+		}
 	}
 	else if (ui_but_is_bool(but)) {
 		return ui_but_is_pushed(but);
@@ -1295,7 +1300,7 @@ static bool ui_drag_toggle_set_xy_xy(
 					/* execute the button */
 					if (ui_drag_toggle_but_is_supported(but)) {
 						/* is it pressed? */
-						int pushed_state_but = ui_drag_toggle_but_pushed_state(but);
+						int pushed_state_but = ui_drag_toggle_but_pushed_state(C, but);
 						if (pushed_state_but != pushed_state) {
 							UI_but_execute(C, but);
 							if (do_check) {
@@ -1754,7 +1759,7 @@ static bool ui_but_drag_init(
 			 * typically 'button_activate_exit()' handles this */
 			ui_apply_but_autokey(C, but);
 
-			drag_info->pushed_state = ui_drag_toggle_but_pushed_state(but);
+			drag_info->pushed_state = ui_drag_toggle_but_pushed_state(C, but);
 			drag_info->but_cent_start[0] = BLI_rctf_cent_x(&but->rect);
 			drag_info->but_cent_start[1] = BLI_rctf_cent_y(&but->rect);
 			copy_v2_v2_int(drag_info->xy_init, &event->x);

source/blender/editors/interface/interface_intern.h

@@ -320,6 +320,9 @@ struct uiBut {
 	void *editcoba;
 	void *editcumap;
 
+	uiButPushedStateFunc pushed_state_func;
+	void *pushed_state_arg;
+
 	/* pointer back */
 	uiBlock *block;
 };

source/blender/editors/space_outliner/outliner_draw.c

@@ -268,6 +268,16 @@ static void restrictbutton_id_user_toggle(bContext *UNUSED(C), void *poin, void
 	}
 }
 
+static int base_pushed_state_cb(bContext *UNUSED(C), void *poin, void *UNUSED(poin2))
+{
+	Base *base = poin;
+	Object *ob = base->object;
+
+	const bool is_visible = ((base->flag & BASE_HIDDEN) == 0) &&
+	                        ((ob->restrictflag & OB_RESTRICT_VIEW) == 0);
+	return !is_visible;
+}
+
 static void hidebutton_base_flag_cb(bContext *C, void *poin, void *poin2)
 {
 	wmWindow *win = CTX_wm_window(C);
@@ -333,6 +343,16 @@ static void hidebutton_base_flag_cb(bContext *C, void *poin, void *poin2)
 	}
 }
 
+static int layer_collection_pushed_state_cb(bContext *UNUSED(C), void *poin, void *UNUSED(poin2))
+{
+	LayerCollection *lc = poin;
+	Collection *collection = lc->collection;
+
+	const bool is_visible = ((lc->flag & LAYER_COLLECTION_RESTRICT_VIEW) == 0) &&
+	                        ((collection->flag & COLLECTION_RESTRICT_VIEW) == 0);
+	return !is_visible;
+}
+
 static void hidebutton_layer_collection_flag_cb(bContext *C, void *poin, void *poin2)
 {
 	wmWindow *win = CTX_wm_window(C);
@@ -602,6 +622,7 @@ static void outliner_draw_restrictbuts(
 					             "* Alt to disable for all viewports\n"
 					             "* Ctrl to isolate visibility"));
 					UI_but_func_set(bt, hidebutton_base_flag_cb, view_layer, base);
+					UI_but_func_pushed_state_set(bt, base_pushed_state_cb, base);
 					UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);
 				}
 				else {
@@ -731,6 +752,7 @@ static void outliner_draw_restrictbuts(
 						             "* Ctrl to isolate visibility\n"
 						             "* Shift to hide inside objects and collections"));
 						UI_but_func_set(bt, hidebutton_layer_collection_flag_cb, view_layer, lc);
+						UI_but_func_pushed_state_set(bt, layer_collection_pushed_state_cb, lc);
 						UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);
 					}
 					else {