display example text on screen

examples/gui/Hello.roc

@@ -1,9 +1,9 @@
 app "hello-gui"
     packages { pf: "platform" }
-    imports [ pf.Action.{ Action }, pf.Elem.{ button, text, row, col } ]
+    imports [ ] #[ pf.Action.{ Action }, pf.Elem.{ button, text, row, col } ]
     provides [ render ] to pf
 
 render =
-    btn = button { onPress : \prev, _ -> Action.none } (text "Hello, button!")
+    # btn = button { onPress : \prev, _ -> Action.none } (text "Hello, button!")
 
     "Hello, World!"

examples/gui/platform/src/gui.rs

@@ -1,7 +1,7 @@
-use crate::graphics::{
+use crate::{graphics::{
     lowlevel::buffer::create_rect_buffers, lowlevel::ortho::update_ortho_buffer,
-    lowlevel::pipelines, primitives::rect::Rect, primitives::text::build_glyph_brush,
+    lowlevel::pipelines, primitives::rect::Rect, primitives::text::{build_glyph_brush, owned_section_from_text, Text}, colors,
-};
+}, rects_and_texts::RectsAndTexts};
 use pipelines::RectResources;
 use roc_std::RocStr;
 use std::error::Error;
@@ -88,6 +88,19 @@ fn run_event_loop(title: &str) -> Result<(), Box<dyn Error>> {
 
     let mut keyboard_modifiers = ModifiersState::empty();
 
+    let mut rects_and_texts = RectsAndTexts::new();
+
+    let hello_text = owned_section_from_text(&Text {
+        position: (50.0, 50.0).into(),
+        area_bounds: (size.width as f32, size.height as f32).into(),
+        color: colors::WHITE,
+        text: "Hello, World!",
+        size: 40.0,
+        ..Default::default()
+    });
+
+    rects_and_texts.add_text_behind(hello_text);
+
     // Render loop
     window.request_redraw();
 
@@ -192,11 +205,11 @@ fn run_event_loop(title: &str) -> Result<(), Box<dyn Error>> {
                     .texture
                     .create_view(&wgpu::TextureViewDescriptor::default());
 
-                // for text_section in &rendered_wgpu.text_sections_behind {
+                for text_section in &rects_and_texts.text_sections_behind {
-                //     let borrowed_text = text_section.to_borrowed();
+                     let borrowed_text = text_section.to_borrowed();
 
-                //     glyph_brush.queue(borrowed_text);
+                     glyph_brush.queue(borrowed_text);
-                // }
+                }
 
                 // draw first layer of text
                 glyph_brush

examples/gui/platform/src/lib.rs

@@ -7,6 +7,7 @@ use std::os::raw::c_char;
 
 mod graphics;
 mod gui;
+mod rects_and_texts;
 
 extern "C" {
     #[link_name = "roc__renderForHost_1_exposed"]

examples/gui/platform/src/rects_and_texts.rs

@@ -0,0 +1,51 @@
+
+use crate::graphics::primitives::rect::Rect;
+use crate::graphics::primitives::text::{owned_section_from_text, Text};
+
+#[derive(Debug)]
+pub struct RectsAndTexts {
+    pub text_sections_behind: Vec<glyph_brush::OwnedSection>, // displayed in front of rect_behind, behind everything else
+    pub text_sections_front: Vec<glyph_brush::OwnedSection>,  // displayed in front of everything
+    pub rects_behind: Vec<Rect>,                              // displayed at lowest depth
+    pub rects_front: Vec<Rect>, // displayed in front of text_sections_behind, behind text_sections_front
+}
+
+impl RectsAndTexts {
+    pub fn new() -> Self {
+        Self {
+            text_sections_behind: Vec::new(),
+            text_sections_front: Vec::new(),
+            rects_behind: Vec::new(),
+            rects_front: Vec::new(),
+        }
+    }
+
+    pub fn add_text_behind(&mut self, new_text_section: glyph_brush::OwnedSection) {
+        self.text_sections_behind.push(new_text_section);
+    }
+
+    pub fn add_text_front(&mut self, new_text_section: glyph_brush::OwnedSection) {
+        self.text_sections_front.push(new_text_section);
+    }
+
+    pub fn add_rect_behind(&mut self, new_rect: Rect) {
+        self.rects_behind.push(new_rect);
+    }
+
+    pub fn add_rects_behind(&mut self, new_rects: Vec<Rect>) {
+        self.rects_behind.extend(new_rects);
+    }
+
+    pub fn add_rect_front(&mut self, new_rect: Rect) {
+        self.rects_front.push(new_rect);
+    }
+
+    pub fn extend(&mut self, rects_and_texts: RectsAndTexts) {
+        self.text_sections_behind
+            .extend(rects_and_texts.text_sections_behind);
+        self.text_sections_front
+            .extend(rects_and_texts.text_sections_front);
+        self.rects_behind.extend(rects_and_texts.rects_behind);
+        self.rects_front.extend(rects_and_texts.rects_front);
+    }
+}