text size calculation and very primitive row layout

abletk-common/src/lib.rs

@@ -69,6 +69,14 @@ impl Renderer {
         self.renderer.fill_rect(rect)
     }
 
+    pub fn get_text_size(&self, text: &str) -> (u32, u32) {
+        self.renderer.get_text_size(text)
+    }
+
+    pub fn position(&self) -> (u32, u32) {
+        (self.x, self.y)
+    }
+
     pub fn position_at(&mut self, x: u32, y: u32) {
         self.x = x;
         self.y = y

abletk-direct2d/src/lib.rs

@@ -91,6 +91,21 @@ impl Renderer {
         }
     }
 
+    pub fn get_text_size(&self, text: &str) -> (u32, u32) {
+        let metrics = unsafe {
+            let layout = self.dw_factory.CreateTextLayout(
+                // fixme: make this not hacky
+                &text.as_bytes().iter().map(|b| *b as u16).collect::<Vec<_>>(),
+                &self.text_format,
+                f32::INFINITY,
+                f32::INFINITY,
+            ).unwrap();
+            layout.GetMetrics().unwrap()
+        };
+
+        (metrics.widthIncludingTrailingWhitespace as u32, metrics.height as u32)
+    }
+
     pub fn resized(&mut self, width: u32, height: u32) {
         unsafe {
             if let Some(target) = self.target.as_ref() {

src/lib.rs

@@ -24,6 +24,7 @@ pub mod prelude {
     pub use crate::event::window::Event as WindowEvent;
     pub use crate::platform::Platform;
     pub use crate::widget::Label;
+    pub use crate::widget::Row;
     pub use crate::widget::Widget;
     pub use crate::window::*;
     pub use crate::rgb;

src/main.rs

@@ -14,6 +14,9 @@ fn launch() -> _ {
     Application::new()
         .apply_plugin(QuitPlugin)
         .add_window(Window::builder(
-            Label::new("Hello, AbleTK!")
-                .color(rgb!(0xFF00FFFF))))
+            Row::new()
+                .add(Label::new("Hello, AbleTK! ")
+                    .color(rgb!(0xFF00FFFF)))
+                .add(Label::new("Hello, World!")
+                    .color(rgb!(0x64CAFEFF)))))
 }

src/widget/label.rs

@@ -6,7 +6,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/.
  */
 
-use abletk_common::{Renderer, brush::Brush, color::Color};
+use abletk_common::{Renderer, brush::Brush, color::Color, rgb};
 use crate::{widget::Widget, layout::position::Position};
 
 pub struct Label {
@@ -20,8 +20,9 @@ impl Widget for Label {
         renderer.draw_text(&self.text);
     }
 
-    fn position(&self) -> Position {
-        Position::new(100, 0, 0, 0)
+    fn position(&self, renderer: &mut Renderer) -> Position {
+        let (width, height) = renderer.get_text_size(&self.text);
+        Position::new(0, 0, width, height)
     }
 }
 
@@ -29,7 +30,7 @@ impl Label {
     pub fn new<S: Into<String>>(text: S) -> Self {
         Self {
             text: text.into(),
-            color: Color(1.0, 1.0, 1.0, 1.0),
+            color: rgb!(0xFFFFFFFF),
         }
     }
 

src/widget/mod.rs

@@ -7,13 +7,16 @@
  */
 
 mod label;
+mod row;
 
 use abletk_common::Renderer;
 pub use label::*;
+pub use row::*;
 
 use crate::layout::position::Position;
 
 pub trait Widget {
     fn draw(&self, renderer: &mut Renderer);
-    fn position(&self) -> Position;
+    // fixme: don't pass renderer
+    fn position(&self, renderer: &mut Renderer) -> Position;
 }

src/widget/row.rs

@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2022 Umut İnan Erdoğan <umutinanerdogan@pm.me>
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+use crate::{layout::position::Position, widget::Widget};
+use abletk_common::Renderer;
+
+pub struct Row {
+    widgets: Vec<Box<dyn Widget>>,
+}
+
+impl Widget for Row {
+    fn draw(&self, renderer: &mut Renderer) {
+        self.widgets.iter().for_each(|widget| {
+            let pos = widget.position(renderer);
+            renderer.position_at(
+                renderer.position().0 + pos.x(),
+                renderer.position().1 + pos.y()
+            );
+            widget.draw(renderer);
+            renderer.position_at(
+                renderer.position().0 + pos.width(),
+                renderer.position().1
+            );
+        });
+    }
+
+    fn position(&self, renderer: &mut Renderer) -> Position {
+        let (width, height) = self.widgets.iter()
+            .map(|widget| widget.position(renderer))
+            .map(|pos| (pos.width(), pos.height()))
+            .fold((0, 0), |accum, item| (
+                accum.0 + item.0,
+                if item.1 > accum.1 { item.1 } else { accum.1 }
+            ));
+
+        Position::new(0, 0, width, height)
+    }
+}
+
+impl Row {
+    pub fn new() -> Self {
+        Self {
+            widgets: Vec::new(),
+        }
+    }
+
+    pub fn add<T: Widget + 'static>(mut self, widget: T) -> Self {
+        self.widgets.push(Box::new(widget));
+        self
+    }
+}

src/window.rs

@@ -72,7 +72,7 @@ impl Window {
     }
 
     pub fn render(&mut self) {
-        let position = self.root.position();
+        let position = self.root.position(&mut self.renderer);
         eprintln!("Rendering window with id {:?}", self.id());
         eprintln!("Root widget position: {position:?}");