pic: initial support

Cargo.toml

@@ -24,9 +24,10 @@ image = { version = "0.25", default-features = false, optional = true }
 image = "0.25"
 
 [features]
-default = ["image", "svg"]
+default = ["image", "svg", "pic"]
 bench = []
 svg = []
+pic = []
 
 [[bin]]
 name = "qrencode"
@@ -41,3 +42,7 @@ name = "encode_string"
 [[example]]
 name = "encode_svg"
 required-features = ["svg"]
+
+[[example]]
+name = "encode_pic"
+required-features = ["pic"]

README.md

@@ -144,3 +144,36 @@ Generates this output:
 █████████████████████████████
 ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀
 ```
+
+## PIC generation
+
+```rust
+use qrcode::render::pic;
+use qrcode::QrCode;
+
+fn main() {
+    let code = QrCode::new(b"01234567").unwrap();
+    let image = code
+        .render::<pic::Color>()
+        .min_dimensions(1, 1)
+        .build();
+    println!("{}", image);
+}
+```
+
+Generates [PIC](https://en.wikipedia.org/wiki/PIC_(markup_language))
+output that renders as follows:
+
+```pic
+maxpswid=29;maxpsht=29;movewid=0;moveht=1;boxwid=1;boxht=1
+define p { box wid $3 ht $4 fill 1 with .nw at $1,-$2 }
+box wid maxpswid ht maxpsht with .nw at 0,0
+p(4,4,1,1)
+p(5,4,1,1)
+p(6,4,1,1)
+p(7,4,1,1)
+p(8,4,1,1)
+p(9,4,1,1)
+…
+```
+See [`test_annex_i_micro_qr_as_pic.pic`](src/test_annex_i_micro_qr_as_pic.pic) for a full example.

examples/encode_pic.roff

@@ -0,0 +1,16 @@
+.\" To convert this file to pdf use:
+.\" groff -Tpdf -P-p14.5c,14.5c -p encode_pic.roff > encode_pic.pdf
+.
+.po -1i
+.vs 0
+.
+.\" For most flexibility include the QR-Code using copy
+.\" and define your preferred picture scale, e.g.:
+.PS
+# To make the QR-Code smaller make scale a larger number
+# To make the QR-Code bigger make scale a smaller number
+scale=2.54*2
+# To generate encode_pic.pic run: cargo run --example encode_pic > encode_pic.pic
+copy "encode_pic.pic"
+.PE
+.ex

examples/encode_pic.rs

@@ -0,0 +1,8 @@
+use qrcode::render::pic;
+use qrcode::QrCode;
+
+fn main() {
+    let code = QrCode::new(b"01234567").unwrap();
+    let image = code.render::<pic::Color>().min_dimensions(1, 1).build();
+    println!("{}", image);
+}

src/lib.rs

@@ -374,3 +374,25 @@ mod svg_tests {
         assert_eq!(&image, expected);
     }
 }
+
+#[cfg(all(test, feature = "pic"))]
+mod pic_tests {
+    use crate::render::pic::Color as PicColor;
+    use crate::{EcLevel, QrCode, Version};
+
+    #[test]
+    fn test_annex_i_qr_as_pic() {
+        let code = QrCode::new(b"01234567").unwrap();
+        let image = code.render::<PicColor>().build();
+        let expected = include_str!("test_annex_i_qr_as_pic.pic");
+        assert_eq!(&image, expected);
+    }
+
+    #[test]
+    fn test_annex_i_micro_qr_as_pic() {
+        let code = QrCode::with_version(b"01234567", Version::Micro(2), EcLevel::L).unwrap();
+        let image = code.render::<PicColor>().min_dimensions(1, 1).build();
+        let expected = include_str!("test_annex_i_micro_qr_as_pic.pic");
+        assert_eq!(&image, expected);
+    }
+}

src/render/mod.rs

@@ -5,6 +5,7 @@ use crate::types::Color;
 use std::cmp::max;
 
 pub mod image;
+pub mod pic;
 pub mod string;
 pub mod svg;
 pub mod unicode;

src/render/pic.rs

@@ -0,0 +1,67 @@
+//! PIC rendering support.
+//!
+//! # Example
+//!
+//! ```
+//! use qrcode::QrCode;
+//! use qrcode::render::pic;
+//!
+//! let code = QrCode::new(b"Hello").unwrap();
+//! let pic = code.render::<pic::Color>().build();
+//! println!("{}", pic);
+
+#![cfg(feature = "pic")]
+
+use std::fmt::Write;
+
+use crate::render::{Canvas as RenderCanvas, Pixel};
+use crate::types::Color as ModuleColor;
+
+/// A PIC color.
+#[derive(Copy, Clone, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct Color;
+
+impl Pixel for Color {
+    type Canvas = Canvas;
+    type Image = String;
+
+    fn default_color(_color: ModuleColor) -> Self {
+        Color
+    }
+}
+
+#[doc(hidden)]
+pub struct Canvas {
+    pic: String,
+}
+
+impl RenderCanvas for Canvas {
+    type Pixel = Color;
+    type Image = String;
+
+    fn new(width: u32, height: u32, _dark_pixel: Color, _light_pixel: Color) -> Self {
+        Canvas {
+            pic: format!(
+                concat!(
+                    "maxpswid={w};maxpsht={h};movewid=0;moveht=1;boxwid=1;boxht=1\n",
+                    "define p {{ box wid $3 ht $4 fill 1 with .nw at $1,-$2 }}\n",
+                    "box wid maxpswid ht maxpsht with .nw at 0,0\n",
+                ),
+                w = width,
+                h = height
+            ),
+        }
+    }
+
+    fn draw_dark_pixel(&mut self, x: u32, y: u32) {
+        self.draw_dark_rect(x, y, 1, 1);
+    }
+
+    fn draw_dark_rect(&mut self, left: u32, top: u32, width: u32, height: u32) {
+        write!(self.pic, "p({left},{top},{width},{height})\n").unwrap();
+    }
+
+    fn into_image(mut self) -> String {
+        self.pic
+    }
+}

src/test_annex_i_micro_qr_as_pic.pic

@@ -0,0 +1,96 @@
+maxpswid=17;maxpsht=17;movewid=0;moveht=1;boxwid=1;boxht=1
+define p { box wid $3 ht $4 fill 1 with .nw at $1,-$2 }
+box wid maxpswid ht maxpsht with .nw at 0,0
+p(2,2,1,1)
+p(3,2,1,1)
+p(4,2,1,1)
+p(5,2,1,1)
+p(6,2,1,1)
+p(7,2,1,1)
+p(8,2,1,1)
+p(10,2,1,1)
+p(12,2,1,1)
+p(14,2,1,1)
+p(2,3,1,1)
+p(8,3,1,1)
+p(10,3,1,1)
+p(11,3,1,1)
+p(12,3,1,1)
+p(14,3,1,1)
+p(2,4,1,1)
+p(4,4,1,1)
+p(5,4,1,1)
+p(6,4,1,1)
+p(8,4,1,1)
+p(11,4,1,1)
+p(12,4,1,1)
+p(14,4,1,1)
+p(2,5,1,1)
+p(4,5,1,1)
+p(5,5,1,1)
+p(6,5,1,1)
+p(8,5,1,1)
+p(11,5,1,1)
+p(12,5,1,1)
+p(13,5,1,1)
+p(14,5,1,1)
+p(2,6,1,1)
+p(4,6,1,1)
+p(5,6,1,1)
+p(6,6,1,1)
+p(8,6,1,1)
+p(10,6,1,1)
+p(11,6,1,1)
+p(12,6,1,1)
+p(2,7,1,1)
+p(8,7,1,1)
+p(10,7,1,1)
+p(14,7,1,1)
+p(2,8,1,1)
+p(3,8,1,1)
+p(4,8,1,1)
+p(5,8,1,1)
+p(6,8,1,1)
+p(7,8,1,1)
+p(8,8,1,1)
+p(11,8,1,1)
+p(12,8,1,1)
+p(13,8,1,1)
+p(14,8,1,1)
+p(11,9,1,1)
+p(12,9,1,1)
+p(2,10,1,1)
+p(3,10,1,1)
+p(5,10,1,1)
+p(10,10,1,1)
+p(14,10,1,1)
+p(3,11,1,1)
+p(4,11,1,1)
+p(6,11,1,1)
+p(8,11,1,1)
+p(10,11,1,1)
+p(12,11,1,1)
+p(14,11,1,1)
+p(2,12,1,1)
+p(3,12,1,1)
+p(4,12,1,1)
+p(7,12,1,1)
+p(8,12,1,1)
+p(9,12,1,1)
+p(10,12,1,1)
+p(11,12,1,1)
+p(12,12,1,1)
+p(13,12,1,1)
+p(5,13,1,1)
+p(7,13,1,1)
+p(12,13,1,1)
+p(13,13,1,1)
+p(2,14,1,1)
+p(3,14,1,1)
+p(4,14,1,1)
+p(6,14,1,1)
+p(9,14,1,1)
+p(10,14,1,1)
+p(12,14,1,1)
+p(13,14,1,1)
+p(14,14,1,1)