From 6cb4d68f5be1321764911a6b80e81d3bcf12cfed Mon Sep 17 00:00:00 2001
From: Michael Wildman <Michael.Wildman@bentley.com>
Date: Wed, 13 Sep 2023 09:42:38 -0600
Subject: [PATCH] Support symbology by layer, take global origin into account,
 ensure last and first point of a closed geometry fit exactly.

---
 ogr/ogrsf_frmts/dwg/dgnv8_headers.h        |  1 +
 ogr/ogrsf_frmts/dwg/ogrdgnv8datasource.cpp |  1 +
 ogr/ogrsf_frmts/dwg/ogrdgnv8layer.cpp      | 49 +++++++++++++++++++++-
 3 files changed, 49 insertions(+), 2 deletions(-)

diff --git a/ogr/ogrsf_frmts/dwg/dgnv8_headers.h b/ogr/ogrsf_frmts/dwg/dgnv8_headers.h
index df1d951e0b7d..364c1564245b 100644
--- a/ogr/ogrsf_frmts/dwg/dgnv8_headers.h
+++ b/ogr/ogrsf_frmts/dwg/dgnv8_headers.h
@@ -75,5 +75,6 @@
 #include "DgSharedCellReference.h"
 #include "DgText.h"
 #include "DgTextNode.h"
+#include "DgLevelTableRecord.h"
 
 #endif  // DGNV8_HEADERS_H
diff --git a/ogr/ogrsf_frmts/dwg/ogrdgnv8datasource.cpp b/ogr/ogrsf_frmts/dwg/ogrdgnv8datasource.cpp
index cca7ee82f2d0..528e2e9e3e31 100644
--- a/ogr/ogrsf_frmts/dwg/ogrdgnv8datasource.cpp
+++ b/ogr/ogrsf_frmts/dwg/ogrdgnv8datasource.cpp
@@ -145,6 +145,7 @@ int OGRDGNV8DataSource::Open(const char *pszFilename, bool bUpdate)
             bUpdate ? OdDg::kForWrite : OdDg::kForRead));
         if (!pModel.isNull())
         {
+            pModel->enableGlobalOriginUsage(true);
             OGRDGNV8Layer *poLayer = new OGRDGNV8Layer(this, pModel);
             m_papoLayers = static_cast<OGRDGNV8Layer **>(CPLRealloc(
                 m_papoLayers, sizeof(OGRDGNV8Layer *) * (m_nLayers + 1)));
diff --git a/ogr/ogrsf_frmts/dwg/ogrdgnv8layer.cpp b/ogr/ogrsf_frmts/dwg/ogrdgnv8layer.cpp
index 28ba995a0078..11a97c20ea25 100644
--- a/ogr/ogrsf_frmts/dwg/ogrdgnv8layer.cpp
+++ b/ogr/ogrsf_frmts/dwg/ogrdgnv8layer.cpp
@@ -705,6 +705,17 @@ IsContiguous(const std::vector<tPairFeatureHoleFlag> &oVectorSubElts,
                     AlmostEqual(oFirstPoint.getX(), oLastPoint.getX()) &&
                     AlmostEqual(oFirstPoint.getY(), oLastPoint.getY()) &&
                     AlmostEqual(oFirstPoint.getZ(), oLastPoint.getZ());
+        if (bIsClosed)
+        {
+          // Make sure that the last point and the first point of the closed geometry fit exactly
+          // otherwise we get into errors in the processing chain
+
+          // Get the last subelement
+          OGRGeometry* poGeom = oVectorSubElts[oVectorSubElts.size()-1].first->GetGeometryRef();
+          OGRSimpleCurve* poCurve = static_cast<OGRSimpleCurve*>(poGeom);
+          // Set the last point of the last subelement to be idetical to the first point of the geometry
+          poCurve->setPoint(poCurve->getNumPoints() - 1, &oFirstPoint);
+        }
     }
     return bIsContiguous;
 }
@@ -745,7 +756,7 @@ OGRDGNV8Layer::ProcessElement(OdDgGraphicsElementPtr element, int level)
     poFeature->SetField("Level", nLevel);
     poFeature->SetField("GraphicGroup",
                         static_cast<int>(element->getGraphicsGroupEntryId()));
-    const OdUInt32 uColorIndex = element->getColorIndex();
+    OdUInt32 uColorIndex = element->getColorIndex();
     CPLString osColor;
     if (uColorIndex != OdDg::kColorByLevel && uColorIndex != OdDg::kColorByCell)
     {
@@ -755,13 +766,33 @@ OGRDGNV8Layer::ProcessElement(OdDgGraphicsElementPtr element, int level)
         osColor = CPLSPrintf(",c:#%02x%02x%02x", ODGETRED(color),
                              ODGETGREEN(color), ODGETBLUE(color));
     }
-    const OdInt32 nLineStyle = element->getLineStyleEntryId();
+    if (uColorIndex == OdDg::kColorByLevel)
+    {
+        OdDgLevelTableRecordPtr myLevel = OdDgLevelTableRecord::cast(element->getLevelId().openObject());
+        uColorIndex = myLevel->getElementColorIndex();
+        OdDgCmEntityColor myColor = OdDgColorTable::lookupTrueColor(element->database(), uColorIndex);
+        poFeature->SetField("ColorIndex",
+            static_cast<int>(uColorIndex));
+
+        osColor = CPLSPrintf(",c:#%02x%02x%02x",
+            myColor.red(),
+            myColor.green(),
+            myColor.blue());
+    }
+    OdInt32 nLineStyle = element->getLineStyleEntryId();
     if (nLineStyle != OdDg::kLineStyleByLevel &&
         nLineStyle != OdDg::kLineStyleByCell)
     {
         poFeature->SetField("Style", nLineStyle);
     }
 
+    if (nLineStyle == OdDg::kLineStyleByLevel)
+    {
+        OdDgLevelTableRecordPtr myLevel = OdDgLevelTableRecord::cast(element->getLevelId().openObject());
+        nLineStyle = myLevel->getElementLineStyleEntryId();
+        poFeature->SetField("Style", nLineStyle);
+    }
+
     const OdUInt32 uLineWeight = element->getLineWeight();
     int nLineWeight = 0;
     if (uLineWeight != OdDg::kLineWeightByLevel &&
@@ -771,6 +802,13 @@ OGRDGNV8Layer::ProcessElement(OdDgGraphicsElementPtr element, int level)
         poFeature->SetField("Weight", nLineWeight);
     }
 
+    if (uLineWeight == OdDg::kLineWeightByLevel)
+    {
+        OdDgLevelTableRecordPtr myLevel = OdDgLevelTableRecord::cast(element->getLevelId().openObject());
+        nLineWeight = static_cast<int>(myLevel->getElementLineWeight());
+        poFeature->SetField("Weight", nLineWeight);
+    }
+
     CPLJSONObject uLinkData;
     CPLJSONArray previousValues;
 
@@ -1604,6 +1642,7 @@ OGRErr OGRDGNV8Layer::DeleteFeature(GIntBig nFID)
 OGRErr OGRDGNV8Layer::GetExtent(OGREnvelope *psExtent, int bForce)
 {
     OdDgModel::StorageUnitDescription description;
+    OdGePoint3d globalOrigin = m_pModel->getGlobalOrigin ();
     m_pModel->getStorageUnit(description);
     OdDgElementIteratorPtr iterator =
         m_pModel->createGraphicsElementsIterator();
@@ -1648,7 +1687,13 @@ OGRErr OGRDGNV8Layer::GetExtent(OGREnvelope *psExtent, int bForce)
         }
     }
     if (bValid)
+    {
+	    psExtent->MinX -= globalOrigin.x;
+	    psExtent->MinY -= globalOrigin.y;
+	    psExtent->MaxX -= globalOrigin.x;
+	    psExtent->MaxY -= globalOrigin.y;
         return OGRERR_NONE;
+	}
     return OGRLayer::GetExtent(psExtent, bForce);
 }