topic Re: How to get object geometry openings in Archicad C++ API

How to get object geometry openings

HalitYagar — Fri, 27 Jun 2025 11:55:44 GMT

Hi I am trying to get object geometries using ArchiCAD API and convert them to .obj files but I couldn't get the openings on the walls. I only got whole geometry of a wall even if it have windows or doors placed on it. What I am missing? Any help is appreciated.

for (Int32 ibody = info3D.fbody; ibody <= info3D.lbody; ibody++) { API_Component3D component = {}; component.header.typeID = API_BodyID; component.header.index = ibody; err = ACAPI_ModelAccess_GetComponent(&component); if (err != NoError) continue; nVert = component.body.nVert; nEdge = component.body.nEdge; nPgon = component.body.nPgon; // Collect vertices std::vector<API_VertType> verts(nVert + 1); for (j = 1; j <= nVert; j++) { component.header.typeID = API_VertID; component.header.index = j; err = ACAPI_ModelAccess_GetComponent(&component); if (err == NoError) { verts[j] = component.vert; char buf[128]; snprintf(buf, sizeof(buf), "v %f %f %f\n", component.vert.x, component.vert.y, component.vert.z); objContent += buf; } } // Collect edges std::vector<API_EdgeType> edges(nEdge + 1); for (j = 1; j <= nEdge; j++) { component.header.typeID = API_EdgeID; component.header.index = j; err = ACAPI_ModelAccess_GetComponent(&component); if (err == NoError) { edges[j] = component.edge; } } // Write faces for (j = 1; j <= nPgon; j++) { component.header.typeID = API_PgonID; component.header.index = j; err = ACAPI_ModelAccess_GetComponent(&component); if (err != NoError) continue; API_PgonType p = component.pgon; // Collect all contours (outer + holes) std::vector<std::vector<int>> contours; std::vector<int> currentContour; for (Int32 pedgIdx = p.fpedg; pedgIdx <= p.lpedg; ++pedgIdx) { component.header.typeID = API_PedgID; component.header.index = pedgIdx; err = ACAPI_ModelAccess_GetComponent(&component); if (err != NoError) break; API_PedgType pedg = component.pedg; if (pedg.pedg == 0) { // End of current contour, start a new one if (!currentContour.empty()) contours.push_back(currentContour); currentContour.clear(); continue; } Int32 edgeIdx = abs(pedg.pedg); if (edgeIdx < 1 || edgeIdx > nEdge) continue; const API_EdgeType& edge = edges[edgeIdx]; int vIdx = (pedg.pedg > 0) ? edge.vert1 : edge.vert2; currentContour.push_back(vertexOffset + vIdx); } if (!currentContour.empty()) contours.push_back(currentContour); // Only export the outer contour (first one) as a face if (!contours.empty() && contours[0].size() >= 3) { const std::vector<int>& faceIndices = contours[0]; for (size_t k = 1; k + 1 < faceIndices.size(); ++k) { char buf[128]; snprintf(buf, sizeof(buf), "f %d %d %d\n", faceIndices[0], faceIndices[k], faceIndices[k + 1]); objContent += buf; } } } vertexOffset += nVert; }

Re: How to get object geometry openings

Hiromichi Shinkawa — Fri, 04 Jul 2025 21:06:47 GMT

Hi, I'd suggest you to try pass the window/door guid and call the following command:

HTH.

elemHead.guid = window_guid; err = ACAPI_ModelAccess_Get3DInfo(elemHead, &info3D); if (err) return; for (Int32 i = info3D.fbody; i <= info3D.lbody; i++) { API_Component3D component{}; component.header.typeID = API_BodyID; component.header.index = i; err = ACAPI_ModelAccess_GetComponent(&component); ...

Re: How to get object geometry openings

HalitYagar — Sat, 05 Jul 2025 22:56:22 GMT

Yes I am also putting window/door guids into that function and it gives me complete geometry of the object. However I cannot get the openings on the walls that have windows on it. I have a simple project with a wall and a windows on it. I can get the wall and windows using guids and Model_Access_API. But I cannot see the opening on the wall where the window should be. Is there a way to get that?

Re: How to get object geometry openings

Hiromichi Shinkawa — Mon, 07 Jul 2025 04:25:30 GMT

Hi, Maybe I'm not fully understand what you meant the opening. You cannot get the opening geometry only as it's represented by wall. I mean if you get the wall geometry, than you can a piece of wall with a hole (opening) geometry.

HTH.

Re: How to get object geometry openings

HalitYagar — Wed, 09 Jul 2025 15:28:34 GMT

I expect the wall should have a hole in its geometry representation where the window placed. But maybe I am thinking wrong.