From 7ea5bc135290dbe5db79e22017a67b23ff6bc890 Mon Sep 17 00:00:00 2001
From: liabru <liabru@brm.io>
Date: Sat, 18 Mar 2023 12:42:29 +0000
Subject: [PATCH] added doc and warning for `Bodies.trapezioid` slope parameter
 range, closes #1075

---
 src/factory/Bodies.js | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/factory/Bodies.js b/src/factory/Bodies.js
index c55e6150..2a373a1e 100644
--- a/src/factory/Bodies.js
+++ b/src/factory/Bodies.js
@@ -54,6 +54,7 @@ var Vector = require('../geometry/Vector');
     
     /**
      * Creates a new rigid body model with a trapezoid hull. 
+     * The `slope` is parameterised as a fraction of `width` and must be < 1 to form a valid trapezoid. 
      * The options parameter is an object that specifies any properties you wish to override the defaults.
      * See the properties section of the `Matter.Body` module for detailed information on what you can pass via the `options` object.
      * @method trapezoid
@@ -61,13 +62,17 @@ var Vector = require('../geometry/Vector');
      * @param {number} y
      * @param {number} width
      * @param {number} height
-     * @param {number} slope
+     * @param {number} slope Must be a number < 1.
      * @param {object} [options]
      * @return {body} A new trapezoid body
      */
     Bodies.trapezoid = function(x, y, width, height, slope, options) {
         options = options || {};
 
+        if (slope >= 1) {
+            Common.warn('Bodies.trapezoid: slope parameter must be < 1.');
+        }
+
         slope *= 0.5;
         var roof = (1 - (slope * 2)) * width;