From a42c16450bf5b3a1bbd748e01d556916d77c387d Mon Sep 17 00:00:00 2001
From: Joseph Lenox <lenox.joseph@gmail.com>
Date: Thu, 26 Jan 2017 20:03:42 -0600
Subject: [PATCH] Reduces the maximum flow for internal infill to 3x nozzle
 diameter (avoid absurdly wide traces at small layer heights).

Fixes #3688
Fixes #2599
---
 xs/src/libslic3r/Flow.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/xs/src/libslic3r/Flow.cpp b/xs/src/libslic3r/Flow.cpp
index 6b3d1986c5..6131534e73 100644
--- a/xs/src/libslic3r/Flow.cpp
+++ b/xs/src/libslic3r/Flow.cpp
@@ -91,14 +91,14 @@ Flow::_auto_width(FlowRole role, float nozzle_diameter, float height) {
     float width = ((nozzle_diameter*nozzle_diameter) * PI + (height*height) * (4.0 - PI)) / (4.0 * height);
     
     float min = nozzle_diameter * 1.05;
-    float max = -1;
+    float max = nozzle_diameter * 3; // cap width to 3x nozzle diameter
     if (role == frExternalPerimeter || role == frSupportMaterial || role == frSupportMaterialInterface) {
         min = max = nozzle_diameter;
     } else if (role != frInfill) {
         // do not limit width for sparse infill so that we use full native flow for it
         max = nozzle_diameter * 1.7;
     }
-    if (max != -1 && width > max) width = max;
+    if (width > max) width = max;
     if (width < min) width = min;
     
     return width;