diff --git a/inventory/static/js/components/draw.js b/inventory/static/js/components/draw.js
index f149cdc..5d6ab97 100644
--- a/inventory/static/js/components/draw.js
+++ b/inventory/static/js/components/draw.js
@@ -166,7 +166,17 @@ function initGridWidget(root, opts = {}) {
 
         let prevLineEnd = null;
 
-        const toInt = (n) => Math.round(Number(n) * q);
+        const MAX_DOC_COORD = 1_000_000;
+        const MAX_INT = MAX_DOC_COORD * q;
+
+        const clampInt = (v) => {
+            if (!Number.isFinite(v)) return 0;
+            if (v > MAX_INT) return MAX_INT;
+            if (v < -MAX_INT) return -MAX_INT;
+            return v;
+        };
+
+        const toInt = (n) => clampInt(Math.round(Number(n) * q));
 
         const resetRun = () => {
             prevKind = null;