diff --git a/poptimal.js b/poptimal.js
index 44b3dbf..dc0cb69 100644
--- a/poptimal.js
+++ b/poptimal.js
@@ -156,13 +156,14 @@ function poptimal_svg(params) {
 
 	params.patterns.map((p) =>  {
 		const dots = dm.dots(1 / p.m, p.n, false);
+		const rfunc = dm.radius(p.f);
 		const dots_g = svg.append("g")
 	  			.attr("id", `dots${p.i}`);
 	
 		dots_g.selectAll("circle")
 		  .data(dots)
 		  .join("circle")
-		  .attr("r", (d) => dm.radius(d, p.f, p.r))
+		  .attr("r", (d) => rfunc(d, p.r))
 		  .attr("fill", p.colour)
 		  .attr("cx", (d) => d.x)
 		  .attr("cy", (d) => d.y);
diff --git a/src/components/dots.js b/src/components/dots.js
index 3b061b3..0030bdd 100644
--- a/src/components/dots.js
+++ b/src/components/dots.js
@@ -11,8 +11,11 @@ const RADIUS_OPTS = [
 	"right-down",
 	"left-up",
 	"left-down",
-	"in",
-	"out",
+	"circle-in",
+	"circle-out",
+	"hyper-in",
+	"hyper-out",
+	"grid",
 	"noise",
 ];
 
@@ -26,15 +29,19 @@ const RADIUS_DESC = {
 	"right-down": "getting larger towards the lower right",
 	"left-up": "getting larger towards the upper left",
 	"left-down": "getting larger towards the lower left",
-	"in": "getting larger in the centre",
-	"out": "getting larger at the edges",
+	"circle-in": "forming a circle at the centre",
+	"circle-out": "leaving a circular gap at the centre",
+	"hyper-in": "forming a starlike pattern at the centre",
+	"hyper-out": "leaving a starlike gap in the centre",
 	"noise": "of random sizes",
+	"grid": "forming a grid pattern",
 }
 
 function distance(dx, dy) {
 	return Math.sqrt(dx ** 2 + dy ** 2);
 }
 
+
 function int_range(v1, v2) {
 	const vs = [v1, v2];
 	vs.sort((a, b) => a - b);
@@ -43,6 +50,10 @@ function int_range(v1, v2) {
 	return [...Array(high - low + 1).keys()].map((i) => i + low);
 }
 
+function randint(min, max) {
+	return min + Math.floor(Math.random() * (max + 1));
+}
+
 class DotMaker {
 	constructor(width, height) {
 		this.width = width;
@@ -71,40 +82,42 @@ class DotMaker {
 		return ps;
 	}
 
-	radius(d, func, maxr) {
+	radius(func) {
 	  	switch (func) {
 	    	case "const":
-	      		return maxr;
+	      		return (d, r) => r;
 	    	case "right":
-	      		return maxr * d.x / this.width;
+	      		return (d, r) => r * d.x / this.width;
 	    	case "left":
-	      		return maxr * (this.width - d.x) / this.width;
+	      		return (d, r) => r * (this.width - d.x) / this.width;
 	    	case "down":
-	      		return maxr * d.y / this.height;
+	      		return (d, r) => r * d.y / this.height;
 	    	case "up":
-	      		return maxr * (this.height - d.y) / this.height;
+	      		return (d, r) => r * (this.height - d.y) / this.height;
 	      	case "right-up":
-	      		return 0.5 * maxr * (d.x + this.height - d.y) / this.wh;
+	      		return (d, r) => 0.5 * r * (d.x + this.height - d.y) / this.wh;
 	      	case "left-up":
-	      		return 0.5 * maxr * (this.width - d.x + this.height - d.y) / this.wh;
+	      		return (d, r) => 0.5 * r * (this.width - d.x + this.height - d.y) / this.wh;
 	      	case "right-down":
-	      		return 0.5 * maxr * (d.x + d.y) / this.wh;
+	      		return (d, r) => 0.5 * r * (d.x + d.y) / this.wh;
 	      	case "left-down":
-	      		return 0.5 * maxr * (this.width - d.x + d.y) / this.wh;
-	      	case "out":
-	      		return 2 * maxr * distance((d.x - this.cx), (d.y - this.cy)) / this.wh;
-	      	case "in":
-	      		return 2 * maxr * (0.5 * this.wh - distance((d.x - this.cx), (d.y - this.cy))) / this.wh;
-
-	      	// case "hyper-out":
-	      	// 	return 2 * maxr * Math.abs(d.x - this.cx) (d.y - this.cy)) / this.width;
-	      	// case "hyper-in":
-	      	// 	return 2 * maxr * (0.5 * this.width - distance((d.x - this.cx), (d.y - this.cy))) / this.width;
-
+	      		return (d, r) => 0.5 * r * (this.width - d.x + d.y) / this.wh;
+	      	case "circle-out":
+	      		return (d, r) => 2 * r * distance((d.x - this.cx), (d.y - this.cy)) / this.wh;
+	      	case "circle-in":
+	      		return (d, r) => 2 * r * (0.5 * this.wh - distance((d.x - this.cx), (d.y - this.cy))) / this.wh;
+	      	case "hyper-in":
+	      		return (d, r) => r * (1 - Math.abs((d.x - this.cx) * (d.y - this.cy)) / this.wh);
+	      	case "hyper-out":
+	      		return (d, r) => r * Math.abs((d.x - this.cx) * (d.y - this.cy)) / this.wh;
 	      	case "noise":
-	      		return maxr * Math.random();
+	      		return (d, r) => r * Math.random();
+	      	case "grid":
+	      		const xk = Math.PI * (2 * randint(1, 10) - 1) / this.width;
+	      		const yk = Math.PI * (2 * randint(1, 10) - 1) / this.height;
+	      		return (d, r) => r * (0.5 + 0.5 * (Math.sin(xk * d.x) + Math.sin(yk * d.y)));
 	    	default:
-	      		return maxr;
+	      		return (d, r) => r;
 	  }
 	}
 }
diff --git a/src/index.md b/src/index.md
index 16add7a..36bb782 100644
--- a/src/index.md
+++ b/src/index.md
@@ -8,7 +8,7 @@ toc: false
 
 colourful generative patterns using [d3](https://d3js.org/) and [Observable Framework](https://observablehq.com/framework/)
 
-<p>v1.2.0 | by <a href="https://mikelynch.org">mike lynch</a> | <a href="https://aus.social/@mikelynch">@mikelynch@aus.social</a> | <a href="https://git.tilde.town/bombinans/poptimal">source</a></p>
+<p>v1.2.1 | by <a href="https://mikelynch.org">mike lynch</a> | <a href="https://aus.social/@mikelynch">@mikelynch@aus.social</a> | <a href="https://git.tilde.town/bombinans/poptimal">source</a></p>
 
 <div class="grid grid-cols-3">
 
@@ -137,6 +137,13 @@ const dots1 = dm.dots(1 / m1, n1, false);
 const dots2 = dm.dots(1 / m2, n2, false);
 
 
+```
+
+```js
+
+const rfunc1 = dm.radius(f1);
+const rfunc2 = dm.radius(f2);
+
 ```
   
 ```js
@@ -210,8 +217,8 @@ display(svg.node());
 ```js
   // separate code block for when I understand transitions better
   
-  dots_g1.selectAll("circle").attr("r", (d) => dm.radius(d, f1, r1));
-  dots_g2.selectAll("circle").attr("r", (d) => dm.radius(d, f2, r2));
+  dots_g1.selectAll("circle").attr("r", (d) => rfunc1(d, r1));
+  dots_g2.selectAll("circle").attr("r", (d) => rfunc2(d, r2));
 
 ```