From 3354f25582d863d921082964509084d7992e00de Mon Sep 17 00:00:00 2001
From: zenoamaro <zenoamaro@gmail.com>
Date: Wed, 26 Jun 2019 21:48:09 +0200
Subject: [PATCH] Circle drawing performance

---
 gfx.js | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/gfx.js b/gfx.js
index 8bf888f..c3cb4eb 100644
--- a/gfx.js
+++ b/gfx.js
@@ -60,11 +60,8 @@ export function strokeRect(ctx, x, y, w, h, color) {
 
 export function drawCircle(ctx, x, y, r, color) {
   for (let cy = -r; cy <= r; cy++) {
-    for (let cx = -r; cx <= r; cx++) {
-      if (cx*cx + cy*cy <= r*r + r*0.85) {
-        plot(ctx, x+cx, y+cy, color);
-      }
-    }
+    const w = Math.round(Math.sqrt(r*r - cy*cy));
+    drawRect(ctx, x-w, y+cy, w*2, 1, color);
   }
 }