Add font rendering

Cargo.lock

@@ -2,6 +2,15 @@
 # It is not intended for manual editing.
 version = 4
 
+[[package]]
+name = "ab_glyph_rasterizer"
+version = "0.1.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "366ffbaa4442f4684d91e2cd7c5ea7c4ed8add41959a31447066e279e432b618"
+dependencies = [
+ "libm",
+]
+
 [[package]]
 name = "allocator-api2"
 version = "0.3.1"
@@ -594,7 +603,9 @@ dependencies = [
  "esp-bootloader-esp-idf",
  "esp-hal",
  "esp-println",
+ "libm",
  "log",
+ "rusttype",
 ]
 
 [[package]]
@@ -826,6 +837,12 @@ version = "0.2.186"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "68ab91017fe16c622486840e4c83c9a37afeff978bd239b5293d61ece587de66"
 
+[[package]]
+name = "libm"
+version = "0.2.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b6d2cec3eae94f9f509c767b45932f1ada8350c4bdb85af2fcab4a3c14807981"
+
 [[package]]
 name = "linked_list_allocator"
 version = "0.10.6"
@@ -874,6 +891,15 @@ dependencies = [
  "autocfg",
 ]
 
+[[package]]
+name = "owned_ttf_parser"
+version = "0.15.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "05e6affeb1632d6ff6a23d2cd40ffed138e82f1532571a26f527c8a284bb2fbb"
+dependencies = [
+ "ttf-parser",
+]
+
 [[package]]
 name = "paste"
 version = "1.0.15"
@@ -1018,6 +1044,17 @@ dependencies = [
  "svgbobdoc",
 ]
 
+[[package]]
+name = "rusttype"
+version = "0.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3ff8374aa04134254b7995b63ad3dc41c7f7236f69528b28553da7d72efaa967"
+dependencies = [
+ "ab_glyph_rasterizer",
+ "libm",
+ "owned_ttf_parser",
+]
+
 [[package]]
 name = "rustversion"
 version = "1.0.22"
@@ -1223,6 +1260,12 @@ dependencies = [
  "winnow",
 ]
 
+[[package]]
+name = "ttf-parser"
+version = "0.15.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7b3e06c9b9d80ed6b745c7159c40b311ad2916abb34a49e9be2653b90db0d8dd"
+
 [[package]]
 name = "typenum"
 version = "1.20.0"

Cargo.toml

@@ -12,7 +12,7 @@ esp-bootloader-esp-idf = { version = "0.5.0", features = ["esp32", "log-04"] }
 log                    = "0.4.27"
 
 critical-section = "1.2.0"
-esp-alloc = "0.10.0"
+esp-alloc = { version = "0.10.0", features = ["esp32"] }
 esp-backtrace = { version = "0.19.0", features = [
   "esp32",
   "panic-handler",
@@ -20,6 +20,11 @@ esp-backtrace = { version = "0.19.0", features = [
 ] }
 esp-println = { version = "0.17.0", features = ["esp32", "log-04"] }
 
+# ttf-parser = {version =  "^0.25.0", features = ["no-std-float"], default-features = false }
+rusttype = {version = "^0.9.0", features = ["libm-math"], default-features = false }
+
+libm = "*"
+
 
 # For fine tuning these settings, please refer to https://doc.rust-lang.org/cargo/reference/profiles.html
 [profile.dev]

src/main.rs

@@ -7,8 +7,9 @@
 )]
 #![deny(clippy::large_stack_frames)]
 
-// use embedded_graphics::{pixelcolor::Rgb565, prelude::DrawTarget};
+use core::{hint::black_box, mem::MaybeUninit};
-// use embedded_hal_bus::spi::ExclusiveDevice;
+
+use alloc::vec::Vec;
 use esp_hal::{
     clock::CpuClock,
     delay::Delay,
@@ -19,16 +20,19 @@ use esp_hal::{
 };
 
 use esp_backtrace as _;
-// use mipidsi::{Builder, interface::SpiInterface, models::ST7789};
+use rusttype::Font;
 
 use crate::display::{Color, Display, Position, Rgb565, SetAddressMode};
+use esp_alloc::HEAP;
 
-// use crate::display::{Color, Display, Position, Rgb565, Rotation};
+use alloc::vec;
 
 extern crate alloc;
 
 mod display;
 
+static OPEN_SANS: &'static [u8] = include_bytes!("./OpenSans_Condensed-Regular.ttf");
+
 // This creates a default app-descriptor required by the esp-idf bootloader.
 // For more information see: <https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-reference/system/app_image_format.html#application-description>
 esp_bootloader_esp_idf::esp_app_desc!();
@@ -91,7 +95,7 @@ fn main() -> ! {
     };
 
     display.init(SetAddressMode {
-        color_order: display::ColorOrder::Bgr,
+        color_order: display::ColorOrder::Rgb,
         ..Default::default()
     });
     display.set_tearing(display::TearingMode::Off);
@@ -102,24 +106,64 @@ fn main() -> ! {
         Rgb565::yellow().as_color(),
     );
 
-    let test_delay = Delay::new();
+    let font = Font::try_from_bytes(OPEN_SANS).unwrap();
+    let glyph = font.glyph('a');
+    const SCALE: u16 = 30;
+    let scale = rusttype::Scale {
+        x: SCALE as f32 * 2.,
+        y: SCALE as f32,
+    };
+    let v_metrics = font.v_metrics(scale);
+    let offset = rusttype::Point {
+        x: 0.0,
+        y: v_metrics.ascent,
+    };
+    let glyphs = font
+        .layout("Hello world", scale, offset)
+        .collect::<Vec<_>>();
 
-    let mut color = 0;
+    let width = libm::ceil(
+        glyphs
+            .iter()
+            .rev()
+            .map(|g| g.position().x as f32 + g.unpositioned().h_metrics().advance_width)
+            .next()
+            .unwrap_or(0.0) as f64,
+    ) as usize;
+
+    let mut pixel_data = vec![Rgb565::white(); SCALE as usize * width];
+
+    for g in glyphs {
+        if let Some(bb) = g.pixel_bounding_box() {
+            g.draw(|x, y, cov| {
+                let x = bb.min.x + x as i32;
+                let y = bb.min.y + y as i32;
+                if x >= 0 && y >= 0 && x < width as i32 && y < SCALE as i32 {
+                    let col = 255 - (255. * cov) as u8;
+                    pixel_data[(x + y * width as i32) as usize] = Rgb565(col, col, col);
+                }
+            });
+        }
+    }
+
+    display.set_window(
+        Position { x: 0, y: 0 },
+        Position {
+            x: width as u16 - 1,
+            y: SCALE as u16 - 1,
+        },
+    );
+    display.write(display::Writeable::Data(
+        &pixel_data
+            .iter()
+            .flat_map(|p| p.as_color().bytes)
+            .collect::<Vec<_>>(),
+    ));
 
     loop {
         let delay_start = Instant::now();
 
-        log::info!("Hello world: {}", color);
+        log::info!("Hello world");
-
-        color = (color + 50) % 200;
-
-        display.draw_rect(
-            Position::new(0, 0),
-            Position::new(240, 240),
-            Color {
-                bytes: [color, color],
-            },
-        );
 
         while delay_start.elapsed() < Duration::from_millis(100) {}
         // test_delay.delay_millis(1);