From 35e0db50fed24df6a3cc463385a118a1728a44ff Mon Sep 17 00:00:00 2001
From: "Kevin M. Gill" <kmsmgill@gmail.com>
Date: Sun, 2 Apr 2023 16:18:28 -0700
Subject: [PATCH] Migrated some shareable code from junocam

---
 src/drawable.rs | 211 ++++++++++++++++++++++++++++++++++++++++++++++++
 src/lib.rs      |   1 +
 src/prelude.rs  |   1 +
 3 files changed, 213 insertions(+)
 create mode 100644 src/drawable.rs

diff --git a/src/drawable.rs b/src/drawable.rs
new file mode 100644
index 0000000..42ca461
--- /dev/null
+++ b/src/drawable.rs
@@ -0,0 +1,211 @@
+use crate::{max, min, prelude::*};
+
+/// A single two-dimensional point on a raster. Contains the x/y coordinate and the RGB values to be placed
+/// into the buffer.
+#[derive(Debug, Clone)]
+pub struct Point {
+    pub x: f64,
+    pub y: f64,
+    pub v: f64,
+}
+
+impl Point {
+    /// Simple creation for a Point.
+    pub fn create(x: f64, y: f64, v: f64) -> Self {
+        Point { x, y, v }
+    }
+}
+
+/// A triangle (polygon) of three two-dimensional points
+pub struct Triangle {
+    pub p0: Point,
+    pub p1: Point,
+    pub p2: Point,
+}
+
+impl Triangle {
+    /// Determine if a two dimensional point is contained within the  area bounded by the triangle
+    pub fn contains(&self, x: f64, y: f64) -> bool {
+        let p = Point { x, y, v: 0.0 };
+        let b0 = Triangle::sign(&p, &self.p0, &self.p1) <= 0.0;
+        let b1 = Triangle::sign(&p, &self.p1, &self.p2) <= 0.0;
+        let b2 = Triangle::sign(&p, &self.p2, &self.p0) <= 0.0;
+
+        (b0 == b1) && (b1 == b2)
+    }
+
+    pub fn sign(p0: &Point, p1: &Point, p2: &Point) -> f64 {
+        (p0.x - p2.x) * (p1.y - p2.y) - (p1.x - p2.x) * (p0.y - p2.y)
+    }
+
+    pub fn x_min(&self) -> f64 {
+        min!(self.p0.x, self.p1.x, self.p2.x)
+    }
+
+    pub fn x_max(&self) -> f64 {
+        max!(self.p0.x, self.p1.x, self.p2.x)
+    }
+
+    pub fn y_min(&self) -> f64 {
+        min!(self.p0.y, self.p1.y, self.p2.y)
+    }
+
+    pub fn y_max(&self) -> f64 {
+        max!(self.p0.y, self.p1.y, self.p2.y)
+    }
+
+    /// Determines an interpolated single-channel color value for a point in the triangle
+    pub fn interpolate_color(&self, x: f64, y: f64, c0: f64, c1: f64, c2: f64) -> f64 {
+        let det = self.p0.x * self.p1.y - self.p1.x * self.p0.y + self.p1.x * self.p2.y
+            - self.p2.x * self.p1.y
+            + self.p2.x * self.p0.y
+            - self.p0.x * self.p2.y;
+        let a = ((self.p1.y - self.p2.y) * c0
+            + (self.p2.y - self.p0.y) * c1
+            + (self.p0.y - self.p1.y) * c2)
+            / det;
+        let b = ((self.p2.x - self.p1.x) * c0
+            + (self.p0.x - self.p2.x) * c1
+            + (self.p1.x - self.p0.x) * c2)
+            / det;
+        let c = ((self.p1.x * self.p2.y - self.p2.x * self.p1.y) * c0
+            + (self.p2.x * self.p0.y - self.p0.x * self.p2.y) * c1
+            + (self.p0.x * self.p1.y - self.p1.x * self.p0.y) * c2)
+            / det;
+
+        a * x + b * y + c
+    }
+}
+
+/// Defines a buffer that can be drawn on using triangle or square polygons.
+pub trait Drawable {
+    /// Create a simple three-channel image buffer
+    fn create(width: usize, height: usize) -> Self;
+
+    /// Create a simple three-channel image buffer
+    fn create_masked(width: usize, height: usize, mask_value: bool) -> Self;
+
+    /// Paint a triangle on the buffer.
+    fn paint_tri(&mut self, tri: &Triangle, avg_pixels: bool, channel: usize);
+
+    /// Paint a square on the buffer using four points
+    fn paint_square(
+        &mut self,
+        tl: &Point,
+        bl: &Point,
+        br: &Point,
+        tr: &Point,
+        avg_pixels: bool,
+        channel: usize,
+    );
+
+    /// Width of the buffer
+    fn get_width(&self) -> usize;
+
+    /// Height of the buffer
+    fn get_height(&self) -> usize;
+
+    /// Converts color to mono
+    fn to_mono(&mut self);
+}
+
+/// Implements the Drawable trait for the RgbImage class. This is probably later be merged fully into RgbImage
+/// in the sciimg crate.
+impl Drawable for Image {
+    fn create(width: usize, height: usize) -> Self {
+        Image::new_with_bands_masked(width, height, 3, ImageMode::U16BIT, true).unwrap()
+    }
+
+    fn create_masked(width: usize, height: usize, mask_value: bool) -> Self {
+        Image::new_with_bands_masked(width, height, 3, ImageMode::U16BIT, mask_value).unwrap()
+    }
+
+    fn get_width(&self) -> usize {
+        self.width
+    }
+
+    fn get_height(&self) -> usize {
+        self.height
+    }
+
+    fn paint_tri(&mut self, tri: &Triangle, avg_pixels: bool, channel: usize) {
+        let min_x = tri.x_min().floor() as usize;
+        let max_x = tri.x_max().ceil() as usize;
+        let min_y = tri.y_min().floor() as usize;
+        let max_y = tri.y_max().ceil() as usize;
+
+        // Gonna limit the max dimension of a poly to just 100x100
+        // to prevent those that wrap the entire image.
+        // Until I plan out a better control to handle polygons that
+        // wrap the cut-off azimuth
+        if max_x - min_x < 100 && max_y - min_y < 100 {
+            for y in min_y..=max_y {
+                for x in min_x..=max_x {
+                    if x < self.width && y < self.height && tri.contains(x as f64, y as f64) {
+                        let mut v =
+                            tri.interpolate_color(x as f64, y as f64, tri.p0.v, tri.p1.v, tri.p2.v);
+
+                        let v0 = self.get_band(channel).get(x, y).unwrap() as f64;
+
+                        if self.get_band(channel).get_mask_at_point(x, y)
+                            && avg_pixels
+                            && (v0 > 0.0)
+                        {
+                            v = (v + v0) / 2.0;
+                        }
+
+                        self.put_alpha(x, y, true);
+
+                        self.put(x, y, v as f32, channel);
+                    }
+                }
+            }
+        }
+    }
+
+    /// Paints a square on the image by breaking it into two triangles.
+    fn paint_square(
+        &mut self,
+        tl: &Point,
+        bl: &Point,
+        br: &Point,
+        tr: &Point,
+        avg_pixels: bool,
+        channel: usize,
+    ) {
+        self.paint_tri(
+            &Triangle {
+                p0: tl.clone(),
+                p1: bl.clone(),
+                p2: tr.clone(),
+            },
+            avg_pixels,
+            channel,
+        );
+        self.paint_tri(
+            &Triangle {
+                p0: tr.clone(),
+                p1: bl.clone(),
+                p2: br.clone(),
+            },
+            avg_pixels,
+            channel,
+        );
+    }
+
+    fn to_mono(&mut self) {
+        if self.num_bands() != 3 {
+            panic!("Cannot convert to mono: Already mono or unsupported number of bands");
+        }
+
+        let r = self.get_band(0).scale(0.2125).unwrap();
+        let g = self.get_band(1).scale(0.7154).unwrap();
+        let b = self.get_band(2).scale(0.0721).unwrap();
+
+        let m = r.add(&g).unwrap().add(&b).unwrap();
+
+        self.set_band(&m, 0);
+        self.set_band(&m, 1);
+        self.set_band(&m, 2);
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
index 7bd34fb..e7bdfb1 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -5,6 +5,7 @@ pub mod blur;
 pub mod camera;
 pub mod debayer;
 pub mod decompanding;
+pub mod drawable;
 pub mod enums;
 pub mod error;
 pub mod guassianblur;
diff --git a/src/prelude.rs b/src/prelude.rs
index 3696331..91f652b 100644
--- a/src/prelude.rs
+++ b/src/prelude.rs
@@ -11,3 +11,4 @@ pub use crate::image::Image;
 pub use crate::imagebuffer::ImageBuffer;
 pub use crate::not_implemented;
 pub use crate::ok;
+pub use crate::path;