From 9427d429c17231efca9befcde448756fdceca2c9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=D0=9F=D0=B5=D0=BB=D0=B8=D0=BF=D0=B5=D0=BD=D0=BA=D0=BE=20?=
 =?UTF-8?q?=D0=98=D0=B2=D0=B0=D0=BD?= <peri4ko@yandex.ru>
Date: Fri, 6 Dec 2019 13:12:10 +0000
Subject: [PATCH] git-svn-id: svn://db.shs.com.ru/libs@657
 a8b55f48-bf90-11e4-a774-851b48703e85

---
 qglengine/core/glmesh.cpp | 13 +++++++++++++
 qglengine/core/glmesh.h   |  1 +
 2 files changed, 14 insertions(+)

diff --git a/qglengine/core/glmesh.cpp b/qglengine/core/glmesh.cpp
index c5c97cc..f275541 100644
--- a/qglengine/core/glmesh.cpp
+++ b/qglengine/core/glmesh.cpp
@@ -342,6 +342,19 @@ void Mesh::transformPoints(const QMatrix4x4 & mat) {
 }
 
 
+void Mesh::flipNormals() {
+	if (vertices_.isEmpty()) return;
+	for (int i = 0; i < triangles_.size(); ++i)
+		piSwap(triangles_[i].p1, triangles_[i].p2);
+	for (int i = 0; i < lines_.size(); ++i)
+		piSwap(lines_[i].p0, lines_[i].p1);
+	int ncnt = normals_.size();
+	for (int i = 0; i < ncnt; ++i)
+		normals_[i] = -normals_[i];
+	changed = hash_changed = true;
+}
+
+
 void Mesh::append(const Mesh * m) {
 	if (!m) return;
 	if (m->isEmpty()) return;
diff --git a/qglengine/core/glmesh.h b/qglengine/core/glmesh.h
index 1244f2c..f882843 100644
--- a/qglengine/core/glmesh.h
+++ b/qglengine/core/glmesh.h
@@ -68,6 +68,7 @@ public:
 	void rotatePoints   (const double & angle, const QVector3D & a);
 	void rotatePoints   (const double & angle, const double & x, const double & y, const double & z) {rotatePoints(angle, QVector3D(x, y, z));}
 	void transformPoints(const QMatrix4x4 & mat);
+	void flipNormals();
 	void append(const Mesh * m);
 
 	bool saveToFile(const QString & filename);