From 7fb3c66d0b94bf7bad03787a3828518cf5fef7f2 Mon Sep 17 00:00:00 2001
From: Emil Ernerfeldt <emilernerfeldt@gmail.com>
Date: Sun, 6 Dec 2020 16:09:36 +0100
Subject: [PATCH] advance_after_rect

---
 egui/src/layout.rs | 49 ++++++++++++++++++++++++++++------------------
 egui/src/ui.rs     | 21 ++++++++------------
 2 files changed, 38 insertions(+), 32 deletions(-)

diff --git a/egui/src/layout.rs b/egui/src/layout.rs
index fab74bf4a..b16797cb7 100644
--- a/egui/src/layout.rs
+++ b/egui/src/layout.rs
@@ -303,25 +303,6 @@ impl Layout {
         rect
     }
 
-    /// Advance the cursor by this many points.
-    pub fn advance_cursor(self, region: &mut Region, amount: f32) {
-        match self.main_dir {
-            Direction::LeftToRight => region.cursor.x += amount,
-            Direction::RightToLeft => region.cursor.x -= amount,
-            Direction::TopDown => region.cursor.y += amount,
-            Direction::BottomUp => region.cursor.y -= amount,
-        }
-    }
-
-    /// Advance the cursor by this spacing
-    pub fn advance_cursor2(self, region: &mut Region, amount: Vec2) {
-        if self.main_dir.is_horizontal() {
-            self.advance_cursor(region, amount.x)
-        } else {
-            self.advance_cursor(region, amount.y)
-        }
-    }
-
     /// Reserve this much space and move the cursor.
     /// Returns where to put the widget.
     ///
@@ -375,6 +356,36 @@ impl Layout {
 
         Rect::from_min_size(child_pos, child_size)
     }
+
+    /// Advance the cursor by this many points.
+    pub fn advance_cursor(self, region: &mut Region, amount: f32) {
+        match self.main_dir {
+            Direction::LeftToRight => region.cursor.x += amount,
+            Direction::RightToLeft => region.cursor.x -= amount,
+            Direction::TopDown => region.cursor.y += amount,
+            Direction::BottomUp => region.cursor.y -= amount,
+        }
+    }
+
+    /// Advance the cursor by this spacing
+    pub fn advance_cursor2(self, region: &mut Region, amount: Vec2) {
+        if self.main_dir.is_horizontal() {
+            self.advance_cursor(region, amount.x)
+        } else {
+            self.advance_cursor(region, amount.y)
+        }
+    }
+
+    /// Advance cursor after a widget was added to a specific rectangle.
+    pub fn advance_after_rect(self, region: &mut Region, rect: Rect, item_spacing: Vec2) {
+        match self.main_dir {
+            Direction::LeftToRight => region.cursor.x = rect.right() + item_spacing.x,
+            Direction::RightToLeft => region.cursor.x = rect.left() - item_spacing.x,
+            Direction::TopDown => region.cursor.y = rect.bottom() + item_spacing.y,
+            Direction::BottomUp => region.cursor.y = rect.top() - item_spacing.y,
+        }
+        region.expand_to_include_rect(rect);
+    }
 }
 
 // ----------------------------------------------------------------------------
diff --git a/egui/src/ui.rs b/egui/src/ui.rs
index cdcd38919..4991e8541 100644
--- a/egui/src/ui.rs
+++ b/egui/src/ui.rs
@@ -439,11 +439,10 @@ impl Ui {
     /// Returns where to put the widget.
     fn allocate_space_impl(&mut self, desired_size: Vec2) -> Rect {
         let child_rect = self.layout.next_space(&self.region, desired_size);
-        self.layout
-            .advance_cursor2(&mut self.region, child_rect.size());
+
         let item_spacing = self.style().spacing.item_spacing;
-        self.layout.advance_cursor2(&mut self.region, item_spacing);
-        self.region.expand_to_include_rect(child_rect);
+        self.layout
+            .advance_after_rect(&mut self.region, child_rect, item_spacing);
 
         self.next_auto_id = self.next_auto_id.wrapping_add(1);
         child_rect
@@ -463,11 +462,9 @@ impl Ui {
         let ret = add_contents(&mut child_ui);
         let child_rect = child_ui.region.max_rect;
 
-        self.layout
-            .advance_cursor2(&mut self.region, child_rect.size());
         let item_spacing = self.style().spacing.item_spacing;
-        self.layout.advance_cursor2(&mut self.region, item_spacing);
-        self.region.expand_to_include_rect(child_rect);
+        self.layout
+            .advance_after_rect(&mut self.region, child_rect, item_spacing);
 
         let response = self.interact_hover(child_rect);
         (ret, response)
@@ -477,7 +474,7 @@ impl Ui {
     /// If the contents overflow, more space will be allocated.
     /// When finished, the amount of space actually used (`min_rect`) will be allocated.
     /// So you can request a lot of space and then use less.
-    fn allocate_ui_min<R>(
+    pub fn allocate_ui_min<R>(
         &mut self,
         initial_size: Vec2,
         add_contents: impl FnOnce(&mut Self) -> R,
@@ -487,11 +484,9 @@ impl Ui {
         let ret = add_contents(&mut child_ui);
         let child_rect = child_ui.region.min_rect;
 
-        self.layout
-            .advance_cursor2(&mut self.region, child_rect.size());
         let item_spacing = self.style().spacing.item_spacing;
-        self.layout.advance_cursor2(&mut self.region, item_spacing);
-        self.region.expand_to_include_rect(child_rect);
+        self.layout
+            .advance_after_rect(&mut self.region, child_rect, item_spacing);
 
         let response = self.interact_hover(child_rect);
         (ret, response)