From 307c164a7b61c5bfd08eaf25236383f070801bb1 Mon Sep 17 00:00:00 2001
From: scislac <scislac@users.sourceforge.net>
Date: Mon, 5 Oct 2009 20:47:05 +0000
Subject: [PATCH] Patch by Johan to fix crashing by undefined path parameters
 in 4 LPEs

---
 src/live_effects/lpe-envelope.cpp         | 9 +++++++++
 src/live_effects/lpe-interpolate.cpp      | 7 ++++++-
 src/live_effects/lpe-mirror_symmetry.cpp  | 5 +++++
 src/live_effects/lpe-patternalongpath.cpp | 7 ++++++-
 4 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/src/live_effects/lpe-envelope.cpp b/src/live_effects/lpe-envelope.cpp
index a730f14ff..abd975b4e 100755
--- a/src/live_effects/lpe-envelope.cpp
+++ b/src/live_effects/lpe-envelope.cpp
@@ -69,6 +69,15 @@ LPEEnvelope::doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > const & pwd
 
     using namespace Geom;
 
+    // Don't allow empty path parameters:
+    if ( bend_path1.get_pathvector().empty()
+         || bend_path2.get_pathvector().empty()
+         || bend_path3.get_pathvector().empty()
+         || bend_path4.get_pathvector().empty() )
+    {
+        return pwd2_in;
+    }
+
     /*
     The code below is inspired from the Bend Path code developed by jfb and mgsloan
     Please, read it before tring to understand this one
diff --git a/src/live_effects/lpe-interpolate.cpp b/src/live_effects/lpe-interpolate.cpp
index e19d2e6e7..e77a392e9 100644
--- a/src/live_effects/lpe-interpolate.cpp
+++ b/src/live_effects/lpe-interpolate.cpp
@@ -52,8 +52,13 @@ LPEInterpolate::~LPEInterpolate()
 Geom::PathVector
 LPEInterpolate::doEffect_path (Geom::PathVector const & path_in)
 {
-    if ( (path_in.size() < 2) || (number_of_steps < 2))
+    if ( (path_in.size() < 2) || (number_of_steps < 2)) {
         return path_in;
+    }
+    // Don't allow empty path parameter:
+    if ( trajectory_path.get_pathvector().empty() ) {
+        return path_in;
+    }
 
     std::vector<Geom::Path> path_out;
 
diff --git a/src/live_effects/lpe-mirror_symmetry.cpp b/src/live_effects/lpe-mirror_symmetry.cpp
index cd724b70e..a3a0faf37 100644
--- a/src/live_effects/lpe-mirror_symmetry.cpp
+++ b/src/live_effects/lpe-mirror_symmetry.cpp
@@ -60,6 +60,11 @@ LPEMirrorSymmetry::doOnApply (SPLPEItem *lpeitem)
 std::vector<Geom::Path>
 LPEMirrorSymmetry::doEffect_path (std::vector<Geom::Path> const & path_in)
 {
+    // Don't allow empty path parameter:
+    if ( reflection_line.get_pathvector().empty() ) {
+        return path_in;
+    }
+
     std::vector<Geom::Path> path_out;
     if (!discard_orig_path) {
         path_out = path_in;
diff --git a/src/live_effects/lpe-patternalongpath.cpp b/src/live_effects/lpe-patternalongpath.cpp
index 29c5517bf..45b2b67b4 100644
--- a/src/live_effects/lpe-patternalongpath.cpp
+++ b/src/live_effects/lpe-patternalongpath.cpp
@@ -33,7 +33,7 @@ B is a map t --> B(t) = ( a(t), b(t) ).
 The first step is to re-parametrize B by its arc length: this is the parametrization in which a point p on B is located by its distance s from start. One obtains a new map s --> U(s) = (a'(s),b'(s)), that still describes the same path B, but where the distance along B from start to
 U(s) is s itself.
 
-We also need a unit normal to the path. This can be obtained by computing a unit tangent vector, and rotate it by 90°. Call this normal vector N(s).
+We also need a unit normal to the path. This can be obtained by computing a unit tangent vector, and rotate it by 90�. Call this normal vector N(s).
 
 The basic deformation associated to B is then given by:
 
@@ -104,6 +104,11 @@ LPEPatternAlongPath::doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > con
 {
     using namespace Geom;
 
+    // Don't allow empty path parameter:
+    if ( pattern.get_pathvector().empty() ) {
+        return pwd2_in;
+    }
+
 /* Much credit should go to jfb and mgsloan of lib2geom development for the code below! */
     Piecewise<D2<SBasis> > output;
     std::vector<Geom::Piecewise<Geom::D2<Geom::SBasis> > > pre_output;
-- 
2.30.2