Hovering tooltip window, bit a bad API

src/app.rs

@@ -37,7 +37,12 @@ impl GuiSettings for App {
             gui.input().screen_size.y,
         ));
 
-        gui.checkbox("checkbox", &mut self.checked);
+        // TODO: add tooltip text with: gui.button("click me").tooltip_text("tooltip")
+        if gui.checkbox("checkbox", &mut self.checked).hovered {
+            gui.tooltip_text(
+                "This is a multiline tooltip that explains the checkbox you are hovering.\nThis is the second line.\nThis is the third.",
+            );
+        }
 
         gui.horizontal(|gui| {
             if gui.radio("First", self.selected_alternative == 0).clicked {
@@ -64,8 +69,7 @@ impl GuiSettings for App {
             gui.slider_f32("stroke_width", &mut self.stroke_width, 0.0, 10.0);
         });
 
-        gui.commands
+        gui.add_paint_command(GuiCmd::PaintCommands(vec![PaintCmd::Rect {
-            .push(GuiCmd::PaintCommands(vec![PaintCmd::Rect {
             corner_radius: self.corner_radius,
             fill_color: Some(srgba(136, 136, 136, 255)),
             pos: vec2(300.0, 100.0),
@@ -77,9 +81,9 @@ impl GuiSettings for App {
         }]));
 
         gui.foldable("LayoutOptions", |gui| {
-            let mut options = gui.options;
+            let mut options = gui.options().clone();
             options.show_gui(gui);
-            gui.options = options;
+            gui.set_options(options);
         });
     }
 }
@@ -93,6 +97,8 @@ impl GuiSettings for crate::layout::LayoutOptions {
         gui.slider_f32("char_size.y", &mut self.char_size.y, 0.0, 20.0);
         gui.slider_f32("item_spacing.x", &mut self.item_spacing.x, 0.0, 10.0);
         gui.slider_f32("item_spacing.y", &mut self.item_spacing.y, 0.0, 10.0);
+        gui.slider_f32("window_padding.x", &mut self.window_padding.x, 0.0, 10.0);
+        gui.slider_f32("window_padding.y", &mut self.window_padding.y, 0.0, 10.0);
         gui.slider_f32("indent", &mut self.indent, 0.0, 100.0);
         gui.slider_f32("width", &mut self.width, 0.0, 1000.0);
         gui.slider_f32("button_padding.x", &mut self.button_padding.x, 0.0, 20.0);

src/emgui.rs

@@ -12,7 +12,7 @@ impl Emgui {
     pub fn new_frame(&mut self, new_input: RawInput) {
         let gui_input = GuiInput::from_last_and_new(&self.last_input, &new_input);
         self.last_input = new_input;
-        self.layout.new_frae(gui_input);
+        self.layout.new_frame(gui_input);
     }
 
     pub fn paint(&mut self) -> Vec<PaintCmd> {

src/layout.rs

@@ -10,7 +10,10 @@ pub struct LayoutOptions {
     /// All text is monospace!
     pub char_size: Vec2,
 
-    // Horizontal and vertical spacing between widgets
+    /// Horizontal and vertical padding within a window frame.
+    pub window_padding: Vec2,
+
+    /// Horizontal and vertical spacing between widgets
     pub item_spacing: Vec2,
 
     /// Indent foldable regions etc by this much.
@@ -32,6 +35,7 @@ impl Default for LayoutOptions {
         LayoutOptions {
             char_size: vec2(7.2, 14.0),
             item_spacing: vec2(8.0, 4.0),
+            window_padding: vec2(6.0, 6.0),
             indent: 21.0,
             width: 250.0,
             button_padding: vec2(5.0, 3.0),
@@ -108,15 +112,15 @@ impl Layouter {
 
 type Id = u64;
 
-/// TODO: non-pub
 #[derive(Clone, Debug, Default)]
 pub struct Layout {
-    pub options: LayoutOptions, // TODO: remove pub
+    options: LayoutOptions,
     input: GuiInput,
     memory: Memory,
     id: Id,
     layouter: Layouter,
-    pub commands: Vec<GuiCmd>, // TODO: remove pub
+    graphics: Vec<GuiCmd>,
+    hovering_graphics: Vec<GuiCmd>,
 }
 
 impl Layout {
@@ -124,13 +128,22 @@ impl Layout {
         &self.input
     }
 
-    pub fn gui_commands(&self) -> &[GuiCmd] {
+    pub fn gui_commands(&self) -> impl Iterator<Item = &GuiCmd> {
-        &self.commands
+        self.graphics.iter().chain(self.hovering_graphics.iter())
+    }
+
+    pub fn options(&self) -> &LayoutOptions {
+        &self.options
+    }
+
+    pub fn set_options(&mut self, options: LayoutOptions) {
+        self.options = options;
     }
 
     // TODO: move
-    pub fn new_frae(&mut self, gui_input: GuiInput) {
+    pub fn new_frame(&mut self, gui_input: GuiInput) {
-        self.commands.clear();
+        self.graphics.clear();
+        self.hovering_graphics.clear();
         self.layouter = Default::default();
         self.input = gui_input;
         if !gui_input.mouse_down {
@@ -147,7 +160,7 @@ impl Layout {
         let text_cursor = self.layouter.cursor + self.options.button_padding;
         let (rect, interact) =
             self.reserve_interactive_space(id, text_size + 2.0 * self.options.button_padding);
-        self.commands.push(GuiCmd::Button { interact, rect });
+        self.graphics.push(GuiCmd::Button { interact, rect });
         self.add_text(text_cursor, text);
         interact
     }
@@ -169,7 +182,7 @@ impl Layout {
         if interact.clicked {
             *checked = !*checked;
         }
-        self.commands.push(GuiCmd::Checkbox {
+        self.graphics.push(GuiCmd::Checkbox {
             checked: *checked,
             interact,
             rect,
@@ -200,7 +213,7 @@ impl Layout {
                 + text_size
                 + self.options.button_padding,
         );
-        self.commands.push(GuiCmd::RadioButton {
+        self.graphics.push(GuiCmd::RadioButton {
             checked,
             interact,
             rect,
@@ -240,7 +253,7 @@ impl Layout {
             );
         }
 
-        self.commands.push(GuiCmd::Slider {
+        self.graphics.push(GuiCmd::Slider {
             interact,
             max,
             min,
@@ -284,7 +297,7 @@ impl Layout {
         }
         let open = self.memory.open_foldables.contains(&id);
 
-        self.commands.push(GuiCmd::FoldableHeader {
+        self.graphics.push(GuiCmd::FoldableHeader {
             interact,
             rect,
             open,
@@ -320,6 +333,42 @@ impl Layout {
         self.layouter.reserve_space(horizontal_layouter.size);
     }
 
+    // ------------------------------------------------------------------------
+    // Free painting. It is up to the caller to make sure there is room for these.
+    pub fn add_paint_command(&mut self, cmd: GuiCmd) {
+        self.graphics.push(cmd);
+    }
+
+    // ------------------------------------------------------------------------
+
+    /// Show some text in a window under mouse position.
+    pub fn tooltip_text<S: Into<String>>(&mut self, text: S) {
+        let window_pos = self.input.mouse_pos + vec2(16.0, 16.0);
+
+        // TODO: less copying
+        let mut popup_layout = Layout {
+            options: self.options,
+            input: self.input,
+            memory: self.memory.clone(), // TODO: Arc
+            id: self.id,
+            layouter: Default::default(),
+            graphics: vec![],
+            hovering_graphics: vec![],
+        };
+        popup_layout.layouter.cursor = window_pos + self.options.window_padding;
+
+        popup_layout.label(text);
+
+        // TODO: handle the last item_spacing in a nicer way
+        let inner_size = popup_layout.layouter.size - self.options.item_spacing;
+        let outer_size = inner_size + 2.0 * self.options.window_padding;
+
+        let rect = Rect::from_min_size(window_pos, outer_size);
+        self.hovering_graphics.push(GuiCmd::Window { rect });
+        self.hovering_graphics
+            .extend(popup_layout.gui_commands().cloned());
+    }
+
     // ------------------------------------------------------------------------
 
     fn reserve_space_default_spacing(&mut self, size: Vec2) -> Rect {
@@ -380,7 +429,7 @@ impl Layout {
 
     fn add_text(&mut self, pos: Vec2, text: Vec<TextFragment>) {
         for fragment in text {
-            self.commands.push(GuiCmd::Text {
+            self.graphics.push(GuiCmd::Text {
                 pos: pos + vec2(fragment.rect.pos.x, fragment.rect.center().y),
                 style: TextStyle::Label,
                 text: fragment.text,

src/style.rs

@@ -255,10 +255,28 @@ fn translate_cmd(out_commands: &mut Vec<PaintCmd>, style: &Style, cmd: GuiCmd) {
                 text,
             });
         }
+        GuiCmd::Window { rect } => {
+            out_commands.push(PaintCmd::Rect {
+                corner_radius: 5.0,
+                fill_color: Some(style.background_fill_color()),
+                outline: Some(Outline {
+                    color: srgba(255, 255, 255, 255), // TODO
+                    width: 1.0,
+                }),
+                pos: rect.pos,
+                size: rect.size,
+            });
+        }
     }
 }
 
-pub fn into_paint_commands(gui_commands: &[GuiCmd], style: &Style) -> Vec<PaintCmd> {
+pub fn into_paint_commands<'a, GuiCmdIterator>(
+    gui_commands: GuiCmdIterator,
+    style: &Style,
+) -> Vec<PaintCmd>
+where
+    GuiCmdIterator: Iterator<Item = &'a GuiCmd>,
+{
     let mut paint_commands = vec![];
     for gui_cmd in gui_commands {
         translate_cmd(&mut paint_commands, style, gui_cmd.clone())

src/types.rs

@@ -119,6 +119,10 @@ pub enum GuiCmd {
         style: TextStyle,
         text: String,
     },
+    /// Background of e.g. a popup
+    Window {
+        rect: Rect,
+    },
 }
 
 // ----------------------------------------------------------------------------