able/qrcode-rust
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Refactor Renderer to support rendering to String.

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Closes #12.
This commit is contained in:
kennytm 2017-05-23 01:41:23 +08:00
parent 3da78c8871
commit 0b3b8f2637
6 changed files with 485 additions and 274 deletions
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17
src/bin/qrencode.rs
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@ -2,22 +2,13 @@ extern crate qrcode;
use std::env;
const SPACE: char = ' '; //'　';
pub fn main() {
let arg = env::args().nth(1).unwrap();
let code = qrcode::QrCode::new(arg.as_bytes()).unwrap();
print!("\n\n\n\n\n{}{}{}{}{}", SPACE, SPACE, SPACE, SPACE, SPACE);
for y in 0 .. code.width() {
for x in 0 .. code.width() {
let block = code[(x, y)].select('█', SPACE);
print!("{}{}", block, block);
}
print!("\n{}{}{}{}{}", SPACE, SPACE, SPACE, SPACE, SPACE);
}
println!("\n\n\n\n");
print!("{}", code.render()
.dark_color("\x1b[7m \x1b[0m")
.light_color("\x1b[49m \x1b[0m")
.build());
}

59
src/lib.rs
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@ -2,26 +2,30 @@
//!
//! This crate provides a QR code and Micro QR code encoder for binary data.
//!
//! ```
#![cfg_attr(feature="image", doc=" ```rust")]
#![cfg_attr(not(feature="image"), doc="```ignore")]
//! extern crate qrcode;
//! # #[cfg(feature="image")]
//! extern crate image;
//!
//! use qrcode::QrCode;
//! # #[cfg(feature="image")]
//! use image::GrayImage;
//! use image::Luma;
//!
//! fn main() {
//! // Encode some data into bits.
//! let code = QrCode::new(b"01234567").unwrap();
//!
//! // Render the bits into an image.
//! # #[cfg(feature="image")]
//! let image: GrayImage = code.render().to_image();
//! let image = code.render::<Luma<u8>>().build();
//!
//! // Save the image.
//! # #[cfg(feature="image")]
//! image.save("/tmp/qrcode.png").unwrap();
//!
//! // You can also render it into a string.
//! let string = code.render()
//! .light_color(' ')
//! .dark_color('#')
//! .build();
//! println!("{}", string);
//! }
//! ```
@ -41,7 +45,7 @@ pub mod render;
pub use types::{QrResult, Color, EcLevel, Version};
#[cfg(feature="image")] use render::{BlankAndWhitePixel, Renderer};
use render::{Pixel, Renderer};
/// The encoded QR code symbol.
#[derive(Clone)]
@ -171,17 +175,11 @@ impl QrCode {
/// Converts the QR code into a human-readable string. This is mainly for
/// debugging only.
pub fn to_debug_str(&self, on_char: char, off_char: char) -> String {
let width = self.width;
let mut k = 0;
let mut res = String::with_capacity(width * (width + 1));
for _ in 0 .. width {
res.push('\n');
for _ in 0 .. width {
res.push(self.content[k].select(on_char, off_char));
k += 1;
}
}
res
self.render()
.quiet_zone(false)
.dark_color(on_char)
.light_color(off_char)
.build()
}
/// Converts the QR code to a vector of booleans. Each entry represents the
@ -214,7 +212,8 @@ impl QrCode {
///
/// # Examples
///
/// ```
#[cfg_attr(feature="image", doc=" ```rust")]
#[cfg_attr(not(feature="image"), doc=" ```ignore")]
/// # extern crate image;
/// # extern crate qrcode;
/// # use qrcode::QrCode;
@ -226,16 +225,15 @@ impl QrCode {
/// .dark_color(Rgb { data: [0, 0, 128] })
/// .light_color(Rgb { data: [224, 224, 224] }) // adjust colors
/// .quiet_zone(false) // disable quiet zone (white border)
/// .min_width(300) // sets minimum image size
/// .to_image();
/// .min_dimensions(300, 300) // sets minimum image size
/// .build();
///
/// # }
/// ```
///
/// Note: the `image` crate itself also provides method to rotate the image,
/// or overlay a logo on top of the QR code.
#[cfg(feature="image")]
pub fn render<P: BlankAndWhitePixel + 'static>(&self) -> Renderer<P> {
pub fn render<P: Pixel>(&self) -> Renderer<P> {
let quiet_zone = if self.version.is_micro() { 2 } else { 4 };
Renderer::new(&self.content, self.width, quiet_zone)
}
@ -258,7 +256,7 @@ mod tests {
fn test_annex_i_qr() {
// This uses the ISO Annex I as test vector.
let code = QrCode::with_version(b"01234567", Version::Normal(1), EcLevel::M).unwrap();
assert_eq!(&*code.to_debug_str('#', '.'), "\n\
assert_eq!(&*code.to_debug_str('#', '.'), "\
#######..#.##.#######\n\
#.....#..####.#.....#\n\
#.###.#.#.....#.###.#\n\
@ -285,7 +283,7 @@ mod tests {
#[test]
fn test_annex_i_micro_qr() {
let code = QrCode::with_version(b"01234567", Version::Micro(2), EcLevel::L).unwrap();
assert_eq!(&*code.to_debug_str('#', '.'), "\n\
assert_eq!(&*code.to_debug_str('#', '.'), "\
#######.#.#.#\n\
#.....#.###.#\n\
#.###.#..##.#\n\
@ -304,13 +302,13 @@ mod tests {
#[cfg(all(test, feature="image"))]
mod image_tests {
use image::{GrayImage, Rgb, load_from_memory};
use image::{Luma, Rgb, load_from_memory};
use {QrCode, Version, EcLevel};
#[test]
fn test_annex_i_qr_as_image() {
let code = QrCode::new(b"01234567").unwrap();
let image: GrayImage = code.render().to_image();
let image = code.render::<Luma<u8>>().build();
let expected = load_from_memory(include_bytes!("test_annex_i_qr_as_image.png")).unwrap().to_luma();
assert_eq!(image.dimensions(), expected.dimensions());
assert_eq!(image.into_raw(), expected.into_raw());
@ -319,10 +317,11 @@ mod image_tests {
#[test]
fn test_annex_i_micro_qr_as_image() {
let code = QrCode::with_version(b"01234567", Version::Micro(2), EcLevel::L).unwrap();
let image = code.render().min_width(200)
let image = code.render()
.min_dimensions(200, 200)
.dark_color(Rgb { data: [128, 0, 0] })
.light_color(Rgb { data: [255, 255, 128] })
.to_image();
.build();
let expected = load_from_memory(include_bytes!("test_annex_i_micro_qr_as_image.png")).unwrap().to_rgb();
assert_eq!(image.dimensions(), expected.dimensions());
assert_eq!(image.into_raw(), expected.into_raw());

228
src/render.rs
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@ -1,228 +0,0 @@
//! Render a QR code into image.
#![cfg(feature="image")]
use image::{Pixel, Rgb, Rgba, Luma, LumaA, Primitive, ImageBuffer};
use types::Color;
/// A pixel which can support black and white colors.
pub trait BlankAndWhitePixel: Pixel {
fn black_color() -> Self;
fn white_color() -> Self;
}
impl<S: Primitive + 'static> BlankAndWhitePixel for Rgb<S> {
fn black_color() -> Self {
Rgb { data: [S::zero(); 3] }
}
fn white_color() -> Self {
Rgb { data: [S::max_value(); 3] }
}
}
impl<S: Primitive + 'static> BlankAndWhitePixel for Rgba<S> {
fn black_color() -> Self {
Rgba { data: [S::zero(), S::zero(), S::zero(), S::max_value()] }
}
fn white_color() -> Self {
Rgba { data: [S::max_value(); 4] }
}
}
impl<S: Primitive + 'static> BlankAndWhitePixel for Luma<S> {
fn black_color() -> Self {
Luma { data: [S::zero()] }
}
fn white_color() -> Self {
Luma { data: [S::max_value()] }
}
}
impl<S: Primitive + 'static> BlankAndWhitePixel for LumaA<S> {
fn black_color() -> Self {
LumaA { data: [S::zero(), S::max_value()] }
}
fn white_color() -> Self {
LumaA { data: [S::max_value(); 2] }
}
}
/// A QR code renderer. This is a builder type which converts a bool-vector into
/// an image.
pub struct Renderer<'a, P: BlankAndWhitePixel> {
content: &'a [Color],
modules_count: u32, // <- we call it `modules_count` here to avoid ambiguity of `width`.
quiet_zone: u32,
module_size: u32,
dark_color: P,
light_color: P,
has_quiet_zone: bool,
}
impl<'a, P: BlankAndWhitePixel + 'static> Renderer<'a, P> {
/// Creates a new renderer.
pub fn new(content: &'a [Color], modules_count: usize, quiet_zone: u32) -> Renderer<'a, P> {
assert!(modules_count * modules_count == content.len());
Renderer {
content: content,
modules_count: modules_count as u32,
quiet_zone: quiet_zone,
module_size: 8,
dark_color: P::black_color(),
light_color: P::white_color(),
has_quiet_zone: true,
}
}
/// Sets color of a dark module. Default is opaque black.
pub fn dark_color(&mut self, color: P) -> &mut Self {
self.dark_color = color;
self
}
/// Sets color of a light module. Default is opaque white.
pub fn light_color(&mut self, color: P) -> &mut Self {
self.light_color = color;
self
}
/// Whether to include the quiet zone in the generated image.
pub fn quiet_zone(&mut self, has_quiet_zone: bool) -> &mut Self {
self.has_quiet_zone = has_quiet_zone;
self
}
/// Sets the size of each module in pixels. Default is 8px.
pub fn module_size(&mut self, size: u32) -> &mut Self {
self.module_size = size;
self
}
/// Sets the minimal total image width (and thus height) in pixels,
/// including the quiet zone if applicable. The renderer will try to find
/// the dimension as small as possible, such that each module in the QR code
/// has uniform size (no distortion).
///
/// For instance, a version 1 QR code has 19 modules across including the
/// quiet zone. If we request an image of width ≥200px, we get that each
/// module's size should be 11px, so the actual image size will be 209px.
pub fn min_width(&mut self, width: u32) -> &mut Self {
let quiet_zone = if self.has_quiet_zone { 2 } else { 0 } * self.quiet_zone;
let width_in_modules = self.modules_count + quiet_zone;
let module_size = (width + width_in_modules - 1) / width_in_modules;
self.module_size(module_size)
}
/// Renders the QR code into an image.
pub fn to_image(&self) -> ImageBuffer<P, Vec<P::Subpixel>> {
let w = self.modules_count;
let qz = if self.has_quiet_zone { self.quiet_zone } else { 0 };
let width = w + 2 * qz;
let ms = self.module_size;
let real_width = width * ms;
let mut image = ImageBuffer::new(real_width, real_width);
let mut i = 0;
for y in 0 .. width {
for x in 0 .. width {
let color = if qz <= x && x < w + qz && qz <= y && y < w + qz {
let c = if self.content[i] != Color::Light {
self.dark_color
} else {
self.light_color
};
i += 1;
c
} else {
self.light_color
};
for yy in y * ms .. (y + 1) * ms {
for xx in x * ms .. (x + 1) * ms {
image.put_pixel(xx, yy, color);
}
}
}
}
image
}
}
#[cfg(test)]
mod render_tests {
use render::Renderer;
use image::{Luma, Rgba};
use types::Color;
#[test]
fn test_render_luma8_unsized() {
let image = Renderer::<Luma<u8>>::new(&[
Color::Light, Color::Dark, Color::Dark,
Color::Dark, Color::Light, Color::Light,
Color::Light, Color::Dark, Color::Light,
], 3, 1).module_size(1).to_image();
let expected = [
255, 255, 255, 255, 255,
255, 255, 0, 0, 255,
255, 0, 255, 255, 255,
255, 255, 0, 255, 255,
255, 255, 255, 255, 255,
];
assert_eq!(image.into_raw(), expected);
}
#[test]
fn test_render_rgba_unsized() {
let image = Renderer::<Rgba<u8>>::new(&[
Color::Light, Color::Dark,
Color::Dark, Color::Dark,
], 2, 1).module_size(1).to_image();
let expected: &[u8] = &[
255,255,255,255, 255,255,255,255, 255,255,255,255, 255,255,255,255,
255,255,255,255, 255,255,255,255, 0, 0, 0,255, 255,255,255,255,
255,255,255,255, 0, 0, 0,255, 0, 0, 0,255, 255,255,255,255,
255,255,255,255, 255,255,255,255, 255,255,255,255, 255,255,255,255,
];
assert_eq!(image.into_raw(), expected);
}
#[test]
fn test_render_resized() {
let image = Renderer::<Luma<u8>>::new(&[
Color::Dark, Color::Light,
Color::Light, Color::Dark,
], 2, 1).min_width(10).to_image();
let expected: &[u8] = &[
255,255,255, 255,255,255, 255,255,255, 255,255,255,
255,255,255, 255,255,255, 255,255,255, 255,255,255,
255,255,255, 255,255,255, 255,255,255, 255,255,255,
255,255,255, 0, 0, 0, 255,255,255, 255,255,255,
255,255,255, 0, 0, 0, 255,255,255, 255,255,255,
255,255,255, 0, 0, 0, 255,255,255, 255,255,255,
255,255,255, 255,255,255, 0, 0, 0, 255,255,255,
255,255,255, 255,255,255, 0, 0, 0, 255,255,255,
255,255,255, 255,255,255, 0, 0, 0, 255,255,255,
255,255,255, 255,255,255, 255,255,255, 255,255,255,
255,255,255, 255,255,255, 255,255,255, 255,255,255,
255,255,255, 255,255,255, 255,255,255, 255,255,255,
];
assert_eq!(image.dimensions(), (12, 12));
assert_eq!(image.into_raw(), expected);
}
}

135
src/render/image.rs Normal file
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@ -0,0 +1,135 @@
#![cfg(feature="image")]
use render::{Pixel, Canvas};
use types::Color;
use image::{Pixel as ImagePixel, Rgb, Rgba, Luma, LumaA, Primitive, ImageBuffer};
macro_rules! impl_pixel_for_image_pixel {
($p:ident<$s:ident>: $c:pat => $d:expr) => {
impl<$s: Primitive + 'static> Pixel for $p<$s> {
type Image = ImageBuffer<Self, Vec<S>>;
type Canvas = (Self, Self::Image);
fn default_color(color: Color) -> Self {
match color.select($s::zero(), $s::max_value()) {
$c => $p { data: $d }
}
}
}
}
}
impl_pixel_for_image_pixel!{ Luma<S>: p => [p] }
impl_pixel_for_image_pixel!{ LumaA<S>: p => [p, S::max_value()] }
impl_pixel_for_image_pixel!{ Rgb<S>: p => [p, p, p] }
impl_pixel_for_image_pixel!{ Rgba<S>: p => [p, p, p, S::max_value()] }
impl<P: ImagePixel + 'static> Canvas for (P, ImageBuffer<P, Vec<P::Subpixel>>) {
type Pixel = P;
type Image = ImageBuffer<P, Vec<P::Subpixel>>;
fn new(width: u32, height: u32, dark_pixel: P, light_pixel: P) -> Self {
(dark_pixel, ImageBuffer::from_pixel(width, height, light_pixel))
}
fn draw_dark_pixel(&mut self, x: u32, y: u32) {
self.1.put_pixel(x, y, self.0);
}
fn into_image(self) -> ImageBuffer<P, Vec<P::Subpixel>> {
self.1
}
}
#[cfg(test)]
mod render_tests {
use render::Renderer;
use image::{Luma, Rgba};
use types::Color;
#[test]
fn test_render_luma8_unsized() {
let image = Renderer::<Luma<u8>>::new(&[
Color::Light, Color::Dark, Color::Dark,
Color::Dark, Color::Light, Color::Light,
Color::Light, Color::Dark, Color::Light,
], 3, 1).module_dimensions(1, 1).build();
let expected = [
255, 255, 255, 255, 255,
255, 255, 0, 0, 255,
255, 0, 255, 255, 255,
255, 255, 0, 255, 255,
255, 255, 255, 255, 255,
];
assert_eq!(image.into_raw(), expected);
}
#[test]
fn test_render_rgba_unsized() {
let image = Renderer::<Rgba<u8>>::new(&[
Color::Light, Color::Dark,
Color::Dark, Color::Dark,
], 2, 1).module_dimensions(1, 1).build();
let expected: &[u8] = &[
255,255,255,255, 255,255,255,255, 255,255,255,255, 255,255,255,255,
255,255,255,255, 255,255,255,255, 0, 0, 0,255, 255,255,255,255,
255,255,255,255, 0, 0, 0,255, 0, 0, 0,255, 255,255,255,255,
255,255,255,255, 255,255,255,255, 255,255,255,255, 255,255,255,255,
];
assert_eq!(image.into_raw(), expected);
}
#[test]
fn test_render_resized_min() {
let image = Renderer::<Luma<u8>>::new(&[
Color::Dark, Color::Light,
Color::Light, Color::Dark,
], 2, 1).min_dimensions(10, 10).build();
let expected: &[u8] = &[
255,255,255, 255,255,255, 255,255,255, 255,255,255,
255,255,255, 255,255,255, 255,255,255, 255,255,255,
255,255,255, 255,255,255, 255,255,255, 255,255,255,
255,255,255, 0, 0, 0, 255,255,255, 255,255,255,
255,255,255, 0, 0, 0, 255,255,255, 255,255,255,
255,255,255, 0, 0, 0, 255,255,255, 255,255,255,
255,255,255, 255,255,255, 0, 0, 0, 255,255,255,
255,255,255, 255,255,255, 0, 0, 0, 255,255,255,
255,255,255, 255,255,255, 0, 0, 0, 255,255,255,
255,255,255, 255,255,255, 255,255,255, 255,255,255,
255,255,255, 255,255,255, 255,255,255, 255,255,255,
255,255,255, 255,255,255, 255,255,255, 255,255,255,
];
assert_eq!(image.dimensions(), (12, 12));
assert_eq!(image.into_raw(), expected);
}
#[test]
fn test_render_resized_max() {
let image = Renderer::<Luma<u8>>::new(&[
Color::Dark, Color::Light,
Color::Light, Color::Dark,
], 2, 1).max_dimensions(10, 5).build();
let expected: &[u8] = &[
255,255, 255,255, 255,255, 255,255,
255,255, 0, 0, 255,255, 255,255,
255,255, 255,255, 0, 0, 255,255,
255,255, 255,255, 255,255, 255,255,
];
assert_eq!(image.dimensions(), (8, 4));
assert_eq!(image.into_raw(), expected);
}
}

188
src/render/mod.rs Normal file
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@ -0,0 +1,188 @@
//! Render a QR code into image.
use std::cmp::max;
use types::Color;
pub mod image;
pub mod string;
//------------------------------------------------------------------------------
//{{{ Pixel trait
/// Abstraction of an image pixel.
pub trait Pixel: Copy + Sized {
/// Type of the finalized image.
type Image: Sized + 'static;
/// The type that stores an intermediate buffer before finalizing to a
/// concrete image
type Canvas: Canvas<Pixel=Self, Image=Self::Image>;
/// Obtains the default module size. The result must be at least 1×1.
fn default_unit_size() -> (u32, u32) {
(8, 8)
}
/// Obtains the default pixel color when a module is dark or light.
fn default_color(color: Color) -> Self;
}
/// Rendering canvas of a QR code image.
pub trait Canvas: Sized {
type Pixel: Sized;
type Image: Sized;
/// Constructs a new canvas of the given dimensions.
fn new(width: u32, height: u32, dark_pixel: Self::Pixel, light_pixel: Self::Pixel) -> Self;
/// Draws a single dark pixel at the (x, y) coordinate.
fn draw_dark_pixel(&mut self, x: u32, y: u32);
fn draw_dark_rect(&mut self, left: u32, top: u32, width: u32, height: u32) {
for y in top .. (top + height) {
for x in left .. (left + width) {
self.draw_dark_pixel(x, y);
}
}
}
/// Finalize the canvas to a real image.
fn into_image(self) -> Self::Image;
}
//}}}
//------------------------------------------------------------------------------
//{{{ Renderer
/// A QR code renderer. This is a builder type which converts a bool-vector into
/// an image.
pub struct Renderer<'a, P: Pixel> {
content: &'a [Color],
modules_count: u32, // <- we call it `modules_count` here to avoid ambiguity of `width`.
quiet_zone: u32,
module_size: (u32, u32),
dark_color: P,
light_color: P,
has_quiet_zone: bool,
}
impl<'a, P: Pixel> Renderer<'a, P> {
/// Creates a new renderer.
pub fn new(content: &'a [Color], modules_count: usize, quiet_zone: u32) -> Renderer<'a, P> {
assert!(modules_count * modules_count == content.len());
Renderer {
content,
modules_count: modules_count as u32,
quiet_zone,
module_size: P::default_unit_size(),
dark_color: P::default_color(Color::Dark),
light_color: P::default_color(Color::Light),
has_quiet_zone: true,
}
}
/// Sets color of a dark module. Default is opaque black.
pub fn dark_color(&mut self, color: P) -> &mut Self {
self.dark_color = color;
self
}
/// Sets color of a light module. Default is opaque white.
pub fn light_color(&mut self, color: P) -> &mut Self {
self.light_color = color;
self
}
/// Whether to include the quiet zone in the generated image.
pub fn quiet_zone(&mut self, has_quiet_zone: bool) -> &mut Self {
self.has_quiet_zone = has_quiet_zone;
self
}
/// Sets the size of each module in pixels. Default is 8px.
#[deprecated(since="0.4.0", note="use `.module_dimensions(width, width)` instead")]
pub fn module_size(&mut self, width: u32) -> &mut Self {
self.module_dimensions(width, width)
}
/// Sets the size of each module in pixels. Default is 8×8.
pub fn module_dimensions(&mut self, width: u32, height: u32) -> &mut Self {
self.module_size = (max(width, 1), max(height, 1));
self
}
#[deprecated(since="0.4.0", note="use `.min_dimensions(width, width)` instead")]
pub fn min_width(&mut self, width: u32) -> &mut Self {
self.min_dimensions(width, width)
}
/// Sets the minimum total image size in pixels, including the quiet zone if
/// applicable. The renderer will try to find the dimension as small as
/// possible, such that each module in the QR code has uniform size (no
/// distortion).
///
/// For instance, a version 1 QR code has 19 modules across including the
/// quiet zone. If we request an image of size ≥200×200, we get that each
/// module's size should be 11×11, so the actual image size will be 209×209.
pub fn min_dimensions(&mut self, width: u32, height: u32) -> &mut Self {
let quiet_zone = if self.has_quiet_zone { 2 } else { 0 } * self.quiet_zone;
let width_in_modules = self.modules_count + quiet_zone;
let unit_width = (width + width_in_modules - 1) / width_in_modules;
let unit_height = (height + width_in_modules - 1) / width_in_modules;
self.module_dimensions(unit_width, unit_height)
}
/// Sets the maximum total image size in pixels, including the quiet zone if
/// applicable. The renderer will try to find the dimension as large as
/// possible, such that each module in the QR code has uniform size (no
/// distortion).
///
/// For instance, a version 1 QR code has 19 modules across including the
/// quiet zone. If we request an image of size ≤200×200, we get that each
/// module's size should be 10×10, so the actual image size will be 190×190.
///
/// The module size is at least 1×1, so if the restriction is too small, the
/// final image *can* be larger than the input.
pub fn max_dimensions(&mut self, width: u32, height: u32) -> &mut Self {
let quiet_zone = if self.has_quiet_zone { 2 } else { 0 } * self.quiet_zone;
let width_in_modules = self.modules_count + quiet_zone;
let unit_width = width / width_in_modules;
let unit_height = height / width_in_modules;
self.module_dimensions(unit_width, unit_height)
}
/// Renders the QR code into an image.
#[deprecated(since="0.4.0", note="renamed to `.build()` to de-emphasize the image connection")]
pub fn to_image(&self) -> P::Image {
self.build()
}
/// Renders the QR code into an image.
pub fn build(&self) -> P::Image {
let w = self.modules_count;
let qz = if self.has_quiet_zone { self.quiet_zone } else { 0 };
let width = w + 2 * qz;
let (mw, mh) = self.module_size;
let real_width = width * mw;
let real_height = width * mh;
let mut canvas = P::Canvas::new(real_width, real_height, self.dark_color, self.light_color);
let mut i = 0;
for y in 0 .. width {
for x in 0 .. width {
if qz <= x && x < w + qz && qz <= y && y < w + qz {
if self.content[i] != Color::Light {
canvas.draw_dark_rect(x*mw, y*mh, mw, mh);
}
i += 1;
}
}
}
canvas.into_image()
}
}
//}}}

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src/render/string.rs Normal file
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//! String rendering support.
use render::{Pixel, Canvas as RenderCanvas};
use types::Color;
pub trait Element: Copy {
fn default_color(color: Color) -> Self;
fn strlen(self) -> usize;
fn append_to_string(self, string: &mut String);
}
impl Element for char {
fn default_color(color: Color) -> Self {
color.select('#', ' ')
}
fn strlen(self) -> usize {
self.len_utf8()
}
fn append_to_string(self, string: &mut String) {
string.push(self)
}
}
impl<'a> Element for &'a str {
fn default_color(color: Color) -> Self {
color.select("#", " ")
}
fn strlen(self) -> usize {
self.len()
}
fn append_to_string(self, string: &mut String) {
string.push_str(self)
}
}
#[doc(hidden)]
pub struct Canvas<P: Element> {
buffer: Vec<P>,
width: usize,
dark_pixel: P,
dark_cap_inc: isize,
capacity: isize,
}
impl<P: Element> Pixel for P {
type Canvas = Canvas<P>;
type Image = String;
fn default_unit_size() -> (u32, u32) {
(1, 1)
}
fn default_color(color: Color) -> Self {
<Self as Element>::default_color(color)
}
}
impl<P: Element> RenderCanvas for Canvas<P> {
type Pixel = P;
type Image = String;
fn new(width: u32, height: u32, dark_pixel: P, light_pixel: P) -> Self {
let width = width as usize;
let height = height as isize;
let dark_cap = dark_pixel.strlen() as isize;
let light_cap = light_pixel.strlen() as isize;
Canvas {
buffer: vec![light_pixel; width * (height as usize)],
width,
dark_pixel,
dark_cap_inc: dark_cap - light_cap,
capacity: light_cap * (width as isize) * height + (height - 1),
}
}
fn draw_dark_pixel(&mut self, x: u32, y: u32) {
let x = x as usize;
let y = y as usize;
self.capacity += self.dark_cap_inc;
self.buffer[x + y*self.width] = self.dark_pixel;
}
fn into_image(self) -> String {
let mut result = String::with_capacity(self.capacity as usize);
for (i, pixel) in self.buffer.into_iter().enumerate() {
if i != 0 && i % self.width == 0 {
result.push('\n');
}
pixel.append_to_string(&mut result);
}
result
}
}
#[test]
fn test_render_to_string() {
use render::Renderer;
let colors = &[
Color::Dark, Color::Light,
Color::Light, Color::Dark,
];
let image: String = Renderer::<char>::new(colors, 2, 1).build();
assert_eq!(&image, " \n # \n # \n ");
let image2 = Renderer::new(colors, 2, 1)
.light_color("A")
.dark_color("!B!")
.module_dimensions(2, 2)
.build();
assert_eq!(&image2, "\
AAAAAAAA\n\
AAAAAAAA\n\
AA!B!!B!AAAA\n\
AA!B!!B!AAAA\n\
AAAA!B!!B!AA\n\
AAAA!B!!B!AA\n\
AAAAAAAA\n\
AAAAAAAA");
}