allow widgets to float over their parent's layout

include/justui/jwidget.h

@@ -87,8 +87,10 @@ typedef struct jwidget {
 	uint update         :1;
 	/* Whether widget is visible inside its parent */
 	uint visible        :1;
+	/* Widget is floating outside the layout (and positioned manually) */
+	uint floating       :1;
 
-	uint :24;
+	uint :23;
 
 } jwidget;
 
@@ -329,6 +331,14 @@ int jwidget_content_height(void *w);
 int jwidget_full_width(void *w);
 int jwidget_full_height(void *w);
 
+/* jwidget_floating(): Whether widget is floating
+   A floating widget is not laid out by its parent's layout, and can be
+   positioned manually. Floating children are rendered after other children. */
+bool jwidget_floating(void *w);
+
+/* jwidget_set_floating(): Make a widget floating or non-floating */
+void jwidget_set_floating(void *w, bool floating);
+
 //---
 // Rendering
 //---

src/jlayout_box.c

@@ -280,7 +280,7 @@ void jlayout_box_apply(void *w0)
 		/* Determine natural length along the container, and stretch child
 		   along the perpendicular direction if possible */
 
-		if(!child->visible) {
+		if(!child->visible || child->floating) {
 			elements[i].stretch = 0;
 			elements[i].max = 0;
 			continue;
@@ -320,7 +320,7 @@ void jlayout_box_apply(void *w0)
 	for(size_t i = 0; i < n; i++) {
 		exp_t *e = &elements[i];
 		jwidget *child = w->children[e->id];
-		if(!child->visible) continue;
+		if(!child->visible || child->floating) continue;
 
 		if(horiz)
 			child->w += e->allocated;
@@ -333,7 +333,7 @@ void jlayout_box_apply(void *w0)
 
 	for(size_t i = 0; i < n; i++) {
 		jwidget *child = w->children[i];
-		if(!child->visible) continue;
+		if(!child->visible || child->floating) continue;
 
 		if(horiz) {
 			child->x = position;

src/jlayout_stack.c

@@ -45,6 +45,7 @@ void jlayout_stack_apply(void *w0)
 
 	for(int k = 0; k < w->child_count; k++) {
 		jwidget *child = w->children[k];
+		if(!child->visible || child->floating) continue;
 
 		/* Maximum size to enforce: this is the acceptable size closest to our
 		   content size (that space we have to distribute) */

src/jwidget.c

@@ -48,14 +48,21 @@ static void jwidget_poly_render(void *w0, int x, int y)
 	/* If there is a stack layout, render active child */
 	if((l = jlayout_get_stack(w)) && l->active >= 0) {
 		jwidget *child = w->children[l->active];
-		if(child->visible) jwidget_render(child, x+child->x, y+child->y);
+		if(child->visible && !child->floating)
+			jwidget_render(child, x+child->x, y+child->y);
 	}
-	/* Otherwise, simply render all children */
-	else {
-		for(int k = 0; k < w->child_count; k++) {
-			jwidget *child = w->children[k];
-			if(child->visible) jwidget_render(child, x+child->x, y+child->y);
-		}
+	/* Otherwise, simply render all non-floating children */
+	else for(int k = 0; k < w->child_count; k++) {
+		jwidget *child = w->children[k];
+		if(child->visible)// && !child->floating)
+			jwidget_render(child, x+child->x, y+child->y);
+	}
+
+	/* Render floating widgets over the layout */
+	for(int k = 0; k < w->child_count; k++) {
+		jwidget *child = w->children[k];
+		if(child->visible && child->floating)
+			jwidget_render(child, x+child->x, y+child->y);
 	}
 }
 
@@ -447,7 +454,7 @@ void jwidget_set_visible(void *w0, bool visible)
 	J_CAST(w)
 	if(w->visible == visible) return;
 
-	w->visible = visible;
+	w->visible = (visible != 0);
 	if(w->parent) w->parent->dirty = 1;
 }
 
@@ -476,7 +483,7 @@ static void jwidget_layout_apply(void *w0)
 	if(!w->visible) return;
 	int t = w->layout;
 
-	if(t == J_LAYOUT_NONE) {
+	if(t == J_LAYOUT_NONE || w->floating) {
 		jwidget_poly const *poly = widget_types[w->type];
 		if(poly->layout) poly->layout(w);
 	}
@@ -549,6 +556,21 @@ int jwidget_full_height(void *w0)
 	return w->h;
 }
 
+bool jwidget_floating(void *w0)
+{
+	J_CAST(w)
+	return w->floating;
+}
+
+void jwidget_set_floating(void *w0, bool floating)
+{
+	J_CAST(w)
+	if(w->floating == floating) return;
+
+	w->floating = (floating != 0);
+	if(w->parent) w->parent->dirty = 1;
+}
+
 //---
 // Rendering
 //---