From 54a7f4b412702718a8f1393731c6f655b3b59afa Mon Sep 17 00:00:00 2001 From: eap Date: Thu, 3 Apr 2014 19:39:48 +0400 Subject: [PATCH] 22539: [CEA 1126] Quadrangle mapping on produces a non conform mesh fix for a case of few (1-2) nb of side divisions --- src/StdMeshers/StdMeshers_Quadrangle_2D.cxx | 122 ++++++++++++++++---- 1 file changed, 101 insertions(+), 21 deletions(-) diff --git a/src/StdMeshers/StdMeshers_Quadrangle_2D.cxx b/src/StdMeshers/StdMeshers_Quadrangle_2D.cxx index 016a5098d..a0e1d0610 100644 --- a/src/StdMeshers/StdMeshers_Quadrangle_2D.cxx +++ b/src/StdMeshers/StdMeshers_Quadrangle_2D.cxx @@ -339,7 +339,7 @@ bool StdMeshers_Quadrangle_2D::computeTriangles(SMESH_Mesh& aMesh, FaceQuadStruct::Ptr newQuad = myQuadList.back(); if ( quad != newQuad ) // split done { - { + { // update left side limit till where to make triangles FaceQuadStruct::Ptr botQuad = // a bottom part ( quad->side[ QUAD_LEFT_SIDE ].from == 0 ) ? quad : newQuad; if ( botQuad->nbNodeOut( QUAD_LEFT_SIDE ) > 0 ) @@ -359,12 +359,33 @@ bool StdMeshers_Quadrangle_2D::computeTriangles(SMESH_Mesh& aMesh, { splitQuad( quad, quad->iSize-2, 0 ); } - if ( quad->nbNodeOut( QUAD_LEFT_SIDE )) + if ( quad->nbNodeOut( QUAD_LEFT_SIDE )) { splitQuad( quad, 1, 0 ); + + if ( quad->nbNodeOut( QUAD_TOP_SIDE )) + { + newQuad = myQuadList.back(); + if ( newQuad == quad ) // too narrow to split + { + // update left side limit till where to make triangles + quad->side[ QUAD_LEFT_SIDE ].to--; + } + else + { + FaceQuadStruct::Ptr leftQuad = + ( quad->side[ QUAD_BOTTOM_SIDE ].from == 0 ) ? quad : newQuad; + leftQuad->nbNodeOut( QUAD_TOP_SIDE ) = 0; + } + } } - return computeQuadDominant( aMesh, aFace ); + if ( ! computeQuadDominant( aMesh, aFace )) + return false; + + // try to fix zero-area triangles near straight-angle corners + + return true; } //================================================================================ @@ -591,17 +612,50 @@ bool StdMeshers_Quadrangle_2D::computeQuadDominant(SMESH_Mesh& aMesh, iup = nbhoriz - 1; int stop = 0; - // if left edge is out, we will stop at a second node - //if (quad->nbNodeOut(3)) stop++; - if ( quad->nbNodeOut( QUAD_RIGHT_SIDE )) - quad->UVPt( nbhoriz-1, 0 ).node = uv_e1[ nbright-2 ].node; - if ( quad->nbNodeOut( QUAD_LEFT_SIDE )) - quad->UVPt( 0, 0 ).node = uv_e3[ nbleft-2 ].node; + if ( quad->side[3].grid->Edge(0).IsNull() ) // left side is simulated one + { + // quad divided at I but not at J, as nbvertic==nbright==2 + stop++; // we stop at a second node + } + else + { + if ( quad->nbNodeOut( QUAD_RIGHT_SIDE )) + quad->UVPt( nbhoriz-1, 0 ).node = uv_e1[ nbright-2 ].node; + if ( quad->nbNodeOut( QUAD_LEFT_SIDE )) + quad->UVPt( 0, 0 ).node = uv_e3[ nbleft-2 ].node; + if ( nbright > 2 ) // there was a split at J + quad->nbNodeOut( QUAD_LEFT_SIDE ) = 0; + } + const SMDS_MeshNode *a, *b, *c, *d; + i = nbup - 1; + // avoid creating zero-area triangles near a straight-angle corner + { + a = uv_e2[i].node; + b = uv_e2[i-1].node; + c = uv_e1[nbright-2].node; + SMESH_TNodeXYZ pa( a ), pb( b ), pc( c ); + double area = 0.5 * (( pb - pa ) ^ ( pc - pa )).Modulus(); + if ( Abs( area ) < 1e-20 ) + { + --g; + d = quad->UVPt( g, nbvertic-2 ).node; + if ( myTrianglePreference ) + { + if ( SMDS_MeshFace* face = myHelper->AddFace(a, d, c)) + meshDS->SetMeshElementOnShape(face, geomFaceID); + } + else + { + if ( SMDS_MeshFace* face = myHelper->AddFace(a, b, d, c)) + meshDS->SetMeshElementOnShape(face, geomFaceID); + --i; + } + } + } // for each node of the up edge find nearest node // in the first row of the regular grid and link them - for (i = nbup - 1; i > stop; i--) { - const SMDS_MeshNode *a, *b, *c, *d; + for ( ; i > stop; i--) { a = uv_e2[i].node; b = uv_e2[i - 1].node; gp_Pnt pb (b->X(), b->Y(), b->Z()); @@ -745,8 +799,34 @@ bool StdMeshers_Quadrangle_2D::computeQuadDominant(SMESH_Mesh& aMesh, int g = nbvertic - 1; // last processed node in the grid int stop = 0; i = quad->side[ QUAD_LEFT_SIDE ].to-1; // nbleft - 1; - for (; i > stop; i--) { - const SMDS_MeshNode *a, *b, *c, *d; + + const SMDS_MeshNode *a, *b, *c, *d; + // avoid creating zero-area triangles near a straight-angle corner + { + a = uv_e3[i].node; + b = uv_e3[i-1].node; + c = quad->UVPt( 1, g ).node; + SMESH_TNodeXYZ pa( a ), pb( b ), pc( c ); + double area = 0.5 * (( pb - pa ) ^ ( pc - pa )).Modulus(); + if ( Abs( area ) < 1e-20 ) + { + --g; + d = quad->UVPt( 1, g ).node; + if ( myTrianglePreference ) + { + if ( SMDS_MeshFace* face = myHelper->AddFace(a, d, c)) + meshDS->SetMeshElementOnShape(face, geomFaceID); + } + else + { + if ( SMDS_MeshFace* face = myHelper->AddFace(a, b, d, c)) + meshDS->SetMeshElementOnShape(face, geomFaceID); + --i; + } + } + } + for (; i > stop; i--) // loop on nodes on the left side + { a = uv_e3[i].node; b = uv_e3[i - 1].node; gp_Pnt pb (b->X(), b->Y(), b->Z()); @@ -756,12 +836,13 @@ bool StdMeshers_Quadrangle_2D::computeQuadDominant(SMESH_Mesh& aMesh, if (i == stop + 1) { // down bondary reached c = quad->uv_grid[nbhoriz*jlow + 1].node; near = jlow; - } else { + } + else { double mind = RealLast(); for (int k = g; k >= jlow; k--) { const SMDS_MeshNode *nk; if (k > jup) - nk = uv_e2[1].node; + nk = quad->uv_grid[nbhoriz*jup + 1].node; //uv_e2[1].node; else nk = quad->uv_grid[nbhoriz*k + 1].node; gp_Pnt pnk (nk->X(), nk->Y(), nk->Z()); @@ -782,11 +863,10 @@ bool StdMeshers_Quadrangle_2D::computeQuadDominant(SMESH_Mesh& aMesh, } else { // make quadrangle if (near + 1 > jup) - d = uv_e2[1].node; + d = quad->uv_grid[nbhoriz*jup + 1].node; //uv_e2[1].node; else d = quad->uv_grid[nbhoriz*(near + 1) + 1].node; - //SMDS_MeshFace* face = meshDS->AddFace(a, b, c, d); - if (!myTrianglePreference){ + if (!myTrianglePreference) { SMDS_MeshFace* face = myHelper->AddFace(a, b, c, d); if (face) meshDS->SetMeshElementOnShape(face, geomFaceID); } @@ -798,7 +878,7 @@ bool StdMeshers_Quadrangle_2D::computeQuadDominant(SMESH_Mesh& aMesh, for (int k = near + 1; k < g; k++) { c = quad->uv_grid[nbhoriz*k + 1].node; if (k + 1 > jup) - d = uv_e2[1].node; + d = quad->uv_grid[nbhoriz*jup + 1].node; //uv_e2[1].node; else d = quad->uv_grid[nbhoriz*(k + 1) + 1].node; SMDS_MeshFace* face = myHelper->AddFace(a, c, d); @@ -4707,7 +4787,7 @@ int StdMeshers_Quadrangle_2D::splitQuad(FaceQuadStruct::Ptr quad, int I, int J) myQuadList.push_back( FaceQuadStruct::Ptr( newQuad )); vector points; - if ( I > 0 ) + if ( I > 0 && I <= quad->iSize-2 ) { points.reserve( quad->jSize ); for ( int jP = 0; jP < quad->jSize; ++jP ) @@ -4746,7 +4826,7 @@ int StdMeshers_Quadrangle_2D::splitQuad(FaceQuadStruct::Ptr quad, int I, int J) return QUAD_LEFT_SIDE; } - else if ( J > 0 ) //// split horizontally, a new quad is below an old one + else if ( J > 0 && J <= quad->jSize-2 ) //// split horizontally, a new quad is below an old one { points.reserve( quad->iSize ); for ( int iP = 0; iP < quad->iSize; ++iP ) -- 2.30.2