Rename to helpers

src/helpers/placement.cpp

@@ -0,0 +1,144 @@
+/********************************************************************************
+ *                                                                              *
+ * This file is part of IfcOpenShell.                                           *
+ *                                                                              *
+ * IfcOpenShell is free software: you can redistribute it and/or modify         *
+ * it under the terms of the Lesser GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3.0 of the License, or          *
+ * (at your option) any later version.                                          *
+ *                                                                              *
+ * IfcOpenShell is distributed in the hope that it will be useful,              *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of               *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the                 *
+ * Lesser GNU General Public License for more details.                          *
+ *                                                                              *
+ * You should have received a copy of the Lesser GNU General Public License     *
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.         *
+ *                                                                              *
+ ********************************************************************************/
+
+#include "Placement.h"
+
+#include "../ifcparse/instance_data.h"
+#include "../ifcparse/schema.h"
+
+#include <vector>
+
+namespace {
+
+Eigen::Vector3d safeNormalize(const Eigen::Vector3d& v,
+                              const Eigen::Vector3d& fallback) {
+    const double n = v.norm();
+    return (n > 0.0) ? Eigen::Vector3d(v / n) : fallback;
+}
+
+std::vector<double> readDirectionRatios(const express::Base& dir) {
+    if (!dir) return {};
+    auto attr = dir.as<express::Entity>().get("DirectionRatios");
+    if (attr.isNull()) return {};
+    return attr;
+}
+
+}  // namespace
+
+Eigen::Matrix4d a2p(const Eigen::Vector3d& origin,
+                    const Eigen::Vector3d& z,
+                    const Eigen::Vector3d& x) {
+    const Eigen::Vector3d xn = safeNormalize(x, Eigen::Vector3d::UnitX());
+    const Eigen::Vector3d zn = safeNormalize(z, Eigen::Vector3d::UnitZ());
+    const Eigen::Vector3d yn = safeNormalize(zn.cross(xn), Eigen::Vector3d::UnitY());
+
+    Eigen::Matrix4d m = Eigen::Matrix4d::Identity();
+    m.block<3, 1>(0, 0) = xn;
+    m.block<3, 1>(0, 1) = yn;
+    m.block<3, 1>(0, 2) = zn;
+    m.block<3, 1>(0, 3) = origin;
+    return m;
+}
+
+Eigen::Matrix4d getAxis2Placement(const express::Base& placement) {
+    if (!placement) return Eigen::Matrix4d::Identity();
+    const auto& decl = placement.declaration();
+    auto entity = placement.as<express::Entity>();
+
+    Eigen::Vector3d z(0.0, 0.0, 1.0);
+    Eigen::Vector3d x(1.0, 0.0, 0.0);
+    Eigen::Vector3d o(0.0, 0.0, 0.0);
+
+    if (decl.is("IfcAxis2Placement3D") || decl.is("IfcAxis2PlacementLinear")) {
+        auto axis_attr = entity.get("Axis");
+        if (!axis_attr.isNull()) {
+            auto dr = readDirectionRatios((express::Base) axis_attr);
+            if (dr.size() >= 3) z = Eigen::Vector3d(dr[0], dr[1], dr[2]);
+        }
+        auto refdir_attr = entity.get("RefDirection");
+        if (!refdir_attr.isNull()) {
+            auto dr = readDirectionRatios((express::Base) refdir_attr);
+            if (dr.size() >= 3) x = Eigen::Vector3d(dr[0], dr[1], dr[2]);
+        }
+        auto loc_attr = entity.get("Location");
+        if (loc_attr.isNull()) return Eigen::Matrix4d::Identity();
+        express::Base location = loc_attr;
+        auto coords_attr = location.as<express::Entity>().get("Coordinates");
+        if (coords_attr.isNull()) return Eigen::Matrix4d::Identity();
+        std::vector<double> coords = coords_attr;
+        if (coords.size() >= 3) o = Eigen::Vector3d(coords[0], coords[1], coords[2]);
+    } else if (decl.is("IfcAxis2Placement2D")) {
+        auto refdir_attr = entity.get("RefDirection");
+        if (!refdir_attr.isNull()) {
+            auto dr = readDirectionRatios((express::Base) refdir_attr);
+            if (dr.size() >= 1) {
+                x = Eigen::Vector3d(dr.size() > 0 ? dr[0] : 1.0,
+                                    dr.size() > 1 ? dr[1] : 0.0,
+                                    0.0);
+            }
+        }
+        auto loc_attr = entity.get("Location");
+        if (loc_attr.isNull()) return Eigen::Matrix4d::Identity();
+        express::Base location = loc_attr;
+        auto coords_attr = location.as<express::Entity>().get("Coordinates");
+        if (coords_attr.isNull()) return Eigen::Matrix4d::Identity();
+        std::vector<double> coords = coords_attr;
+        if (coords.size() >= 2) {
+            o = Eigen::Vector3d(coords[0], coords[1],
+                                coords.size() >= 3 ? coords[2] : 0.0);
+        }
+    } else if (decl.is("IfcAxis1Placement")) {
+        auto axis_attr = entity.get("Axis");
+        if (!axis_attr.isNull()) {
+            auto dr = readDirectionRatios((express::Base) axis_attr);
+            if (dr.size() >= 3) z = Eigen::Vector3d(dr[0], dr[1], dr[2]);
+        }
+        auto loc_attr = entity.get("Location");
+        if (loc_attr.isNull()) return Eigen::Matrix4d::Identity();
+        express::Base location = loc_attr;
+        auto coords_attr = location.as<express::Entity>().get("Coordinates");
+        if (coords_attr.isNull()) return Eigen::Matrix4d::Identity();
+        std::vector<double> coords = coords_attr;
+        if (coords.size() >= 3) o = Eigen::Vector3d(coords[0], coords[1], coords[2]);
+    } else {
+        return Eigen::Matrix4d::Identity();
+    }
+
+    return a2p(o, z, x);
+}
+
+Eigen::Matrix4d getLocalPlacement(const express::Base& placement) {
+    if (!placement) return Eigen::Matrix4d::Identity();
+    const auto& decl = placement.declaration();
+
+    if (decl.is("IfcLocalPlacement")) {
+        auto entity = placement.as<express::Entity>();
+        Eigen::Matrix4d parent = Eigen::Matrix4d::Identity();
+        auto rel_attr = entity.get("PlacementRelTo");
+        if (!rel_attr.isNull()) {
+            parent = getLocalPlacement((express::Base) rel_attr);
+        }
+        auto rp_attr = entity.get("RelativePlacement");
+        if (rp_attr.isNull()) return parent;
+        return parent * getAxis2Placement((express::Base) rp_attr);
+    }
+
+    // IfcAxis2Placement* / IfcAxis1Placement passed in directly.
+    return getAxis2Placement(placement);
+}