add homography transformer

src/transformer/homography.rs

@@ -0,0 +1,36 @@
+use crate::transformer::Transformers;
+use crate::point::Point;
+use crate::worldstate::WorldState;
+use serde::{Serialize,Deserialize};
+use log::info;
+use nalgebra::Matrix3;
+
+/// Homography
+
+#[derive(Serialize,Deserialize,Debug,Clone,Copy)]
+pub struct Homography {}
+
+impl Transformers for Homography {
+    fn apply(&self, point_list: &[Point], ws: &WorldState) -> Vec<Point> {	
+	let m = ws.edh.matrix;
+
+	point_list.iter()
+	    .map(| point | {
+
+		// THIS IS CERTAINLY ALL WRONG! NEEDS DEBUGING!!!
+		
+		let p = Matrix3::new(point.x, point.y, 1.0,
+				     1.0, 1.0, 1.0,
+				     1.0, 1.0, 1.0);
+		let dot = p.tr_dot(&m);
+		let new_p = Point { x: point.x / dot, y: point.y / dot,
+				    ..*point
+		};
+
+		info!("{:?} => {:?}", point, new_p);
+		
+		new_p
+	    })
+	    .collect()
+    }
+}