sized widgets!

src/core/text.rs

@@ -1,13 +1,17 @@
+use cosmic_text::Metrics;
+
 use crate::prelude::*;
 
 pub struct Text {
     pub content: String,
     pub attrs: TextAttrs,
+    buf: TextBuffer,
 }
 
 impl Text {
     pub fn size(mut self, size: impl UiNum) -> Self {
         self.attrs.size = size.to_f32();
+        self.attrs.line_height = self.attrs.size * 1.1;
         self
     }
     pub fn color(mut self, color: UiColor) -> Self {
@@ -21,16 +25,31 @@ impl Text {
 }
 
 impl Widget for Text {
-    fn draw(&self, painter: &mut Painter) {
+    fn draw(&mut self, painter: &mut Painter) {
+        let (handle, offset) = painter.render_text(&mut self.buf, &self.content, &self.attrs);
+        let dims = handle.size();
+        let size = offset.size(&handle);
+        let mut region = painter.region().center().expand(size);
+        region.top_left.offset += offset.top_left;
+        region.bot_right.offset = region.top_left.offset + dims;
+        painter.draw_texture_at(&handle, region);
         // TODO: when on_update is added to painter,
-        // return & store TextureHandle to reuse
-        painter.draw_text(&self.content, &self.attrs);
+        // reuse TextureHandle
+    }
+
+    fn size(&mut self, ctx: SizeCtx) -> Vec2 {
+        let (handle, offset) =
+            ctx.text
+                .draw(&mut self.buf, &self.content, &self.attrs, ctx.textures);
+        offset.size(&handle)
     }
 }
 
 pub fn text(text: impl Into<String>) -> Text {
+    let attrs = TextAttrs::default();
     Text {
         content: text.into(),
-        attrs: TextAttrs::default(),
+        buf: TextBuffer::new_empty(Metrics::new(attrs.size, attrs.line_height)),
+        attrs,
     }
 }