bugfix the three vertices are collinear when converting a polygon to …

…a triangle. Signed-off-by: Jackie9527 <80555200+Jackie9527@users.noreply.github.com>
assimp · Feb 25, 2023 · 93e7450 · 93e7450
1 parent 46ae853
commit 93e7450
Showing 1 changed file with 14 additions and 0 deletions.
diff --git a/code/PostProcessing/TriangulateProcess.cpp b/code/PostProcessing/TriangulateProcess.cpp
@@ -468,6 +468,20 @@ bool TriangulateProcess::TriangulateMesh( aiMesh* pMesh)
                         continue;
                     }
 
+                    // Skip when three point is in a line
+                    aiVector2D left = *pnt0 - *pnt1;
+                    aiVector2D right = *pnt2 - *pnt1;
+
+                    left.Normalize();
+                    right.Normalize();
+                    auto mul = left * right;
+
+                    // if the angle is 0 or 180
+                    if (std::abs(mul - 1.f) < ai_epsilon || std::abs(mul + 1.f) < ai_epsilon) {
+                        // skip this ear
+                        continue;
+                    }
+
                     // and no other point may be contained in this triangle
                     for ( tmp = 0; tmp < max; ++tmp) {