Print random easter egg

showbits-thermal-printer/src/drawer/egg.rs

@@ -0,0 +1,82 @@
+use image::{imageops, RgbaImage};
+use rand::Rng;
+use showbits_assets::{EGG_COVER, EGG_PATTERNS};
+use showbits_common::{
+    color::{self, WHITE},
+    widgets::{Image, Text},
+    Node, Tree, WidgetExt,
+};
+use taffy::{style_helpers::percent, AlignItems, Display, FlexDirection};
+
+use crate::printer::Printer;
+
+use super::{Context, Drawing};
+
+pub struct EggDrawing;
+
+fn load_image(bytes: &[u8]) -> anyhow::Result<RgbaImage> {
+    Ok(image::load_from_memory(bytes)?.into_rgba8())
+}
+
+impl Drawing for EggDrawing {
+    fn draw(&self, printer: &mut Printer, ctx: &mut Context) -> anyhow::Result<()> {
+        // Load image data from memory
+        let cover = load_image(EGG_COVER)?;
+        let mut patterns = vec![];
+        for pattern in EGG_PATTERNS {
+            patterns.push(load_image(pattern)?);
+        }
+
+        // Prepare egg image
+        let mut image =
+            RgbaImage::from_pixel(cover.width(), cover.height(), color::to_image_color(WHITE));
+
+        // Draw patterns onto egg
+        let mut last_idx = None;
+        let mut y = rand::thread_rng().gen_range(-100_i64..0);
+        while y < image.height().into() {
+            let idx = loop {
+                let idx = rand::thread_rng().gen_range(0..patterns.len());
+                if Some(idx) != last_idx {
+                    break idx;
+                }
+            };
+
+            let paint = &patterns[idx];
+            imageops::overlay(&mut image, paint, 0, y);
+            y += <_ as Into<i64>>::into(paint.height());
+            last_idx = Some(idx);
+        }
+
+        // Finally, draw the cover
+        imageops::overlay(&mut image, &cover, 0, 0);
+
+        let mut tree = Tree::<Context>::new(WHITE);
+
+        let image = Image::new(image)
+            .with_grow(false)
+            .with_shrink(false)
+            .node()
+            .register(&mut tree)?;
+
+        let text = Text::new()
+            .with_metrics(Text::default_metrics().scale(2.0))
+            .and_plain("Frohe Ostern!")
+            .widget(&mut ctx.font_stuff)
+            .node()
+            .register(&mut tree)?;
+
+        let root = Node::empty()
+            .with_size_width(percent(1.0))
+            .with_display(Display::Flex)
+            .with_flex_direction(FlexDirection::Column)
+            .with_align_items(Some(AlignItems::Center))
+            .and_child(image)
+            .and_child(text)
+            .register(&mut tree)?;
+
+        printer.print_tree(&mut tree, ctx, root)?;
+        printer.feed()?;
+        Ok(())
+    }
+}