diff --git a/src/util/qpolygon-utils.js b/src/util/qpolygon-utils.js
index 4e9351a8..d4417f9c 100644
--- a/src/util/qpolygon-utils.js
+++ b/src/util/qpolygon-utils.js
@@ -7250,11 +7250,12 @@ const drawHipLine = (points, canvas, roof, textMode, currentRoof, prevDegree, cu
   const baseX = Big(points[0]).minus(Big(points[2])).abs()
   const baseY = Big(points[1]).minus(Big(points[3])).abs()
   if (baseX.gt(1) && baseY.gt(1)) {
-    const base = calcLinePlaneSize({ x1: points[0], y1: points[1], x2: points[2], y2: points[3] }) / 10
-    const heightX = baseX.times(Math.tan((currentDegree * Math.PI) / 180)).round()
-    const heightY = baseY.times(Math.tan((prevDegree * Math.PI) / 180)).round()
-    const degreeX = Math.atan(heightX.div(base).toNumber()) / (Math.PI / 180)
-    const degreeY = Math.atan(heightY.div(base).toNumber()) / (Math.PI / 180)
+    const hypotenuse = calcLinePlaneSize({ x1: points[0], y1: points[1], x2: points[2], y2: points[3] })
+    const base = getAdjacent(hypotenuse)
+    const heightX = base * Math.tan((currentDegree * Math.PI) / 180)
+    const heightY = base * Math.tan((prevDegree * Math.PI) / 180)
+    const degreeX = Math.atan2(heightX, hypotenuse) * (180 / Math.PI)
+    const degreeY = Math.atan2(heightY, hypotenuse) * (180 / Math.PI)
     if (Math.abs(degreeX - degreeY) < 1) {
       currentDegree = degreeX
       prevDegree = degreeY