Patch proj2_meshedit COLLADA parser to support parsing <triangles>

collada-triangles.patch

From ab1517d7e99a7dbe83bc1af335a23060e9ed4015 Mon Sep 17 00:00:00 2001
From: Zhang Hai <dreaming.in.code.zh@gmail.com>
Date: Sun, 18 Feb 2018 22:18:45 -0800
Subject: [PATCH] Support parsing COLLADA <triangles>.

---
 src/collada.cpp | 38 +++++++++++++++++++++++++-------------
 1 file changed, 25 insertions(+), 13 deletions(-)

diff --git a/src/collada.cpp b/src/collada.cpp
index db87115..73451cc 100644
--- a/src/collada.cpp
+++ b/src/collada.cpp
@@ -545,6 +545,11 @@ namespace CGL {
 
       // polylist
       XMLElement* e_polylist = e_mesh->FirstChildElement( "polylist" );
+      bool is_triangles = false;
+      if ( !e_polylist ) {
+        e_polylist = e_mesh->FirstChildElement( "triangles" );
+        is_triangles = true;
+      }
       if ( e_polylist ) {
 
         // material
@@ -639,22 +644,29 @@ namespace CGL {
 
         // create polygon size array and compute size of index array
         vector<size_t> sizes; size_t num_indices = 0;
-        XMLElement* e_vcount = e_polylist->FirstChildElement( "vcount" );
-        if ( e_vcount ) {
-
-          size_t size;
-          string s = e_vcount->GetText();
-          stringstream ss (s);
+        if ( !is_triangles ) {
+          XMLElement *e_vcount = e_polylist->FirstChildElement("vcount");
+          if ( e_vcount ) {
+
+            size_t size;
+            string s = e_vcount->GetText();
+            stringstream ss(s);
+
+            for (size_t i = 0; i < num_polygons; ++i) {
+              ss >> size;
+              sizes.push_back(size);
+              num_indices += size * stride;
+            }
 
-          for (size_t i = 0; i < num_polygons; ++i) {
-            ss >> size;
-            sizes.push_back(size);
-            num_indices += size * stride;
+          } else {
+            stat("Error: polygon sizes undefined in geometry: " << polymesh.id);
+            exit(-1);
           }
-
         } else {
-          stat("Error: polygon sizes undefined in geometry: " << polymesh.id);
-          exit( -1 );
+          for (size_t i = 0; i < num_polygons; ++i) {
+            sizes.push_back(3);
+            num_indices += 3 * stride;
+          }
         }
 
         // index array
--
2.16.1