RepliCAD

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import { cast } from "../shapes";
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import { getOC } from "../oclib";
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import { GCWithScope } from "../register";
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import type { Edge, AnyShape } from "../shapes";
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import type { ProjectionCamera } from "./ProjectionCamera";
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import type { TopoDS_Shape } from "replicad-opencascadejs";
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const getEdges = (shape: TopoDS_Shape) => {
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  if (shape.IsNull()) return [];
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  return cast(shape).edges;
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};
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export function makeProjectedEdges(
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  shape: AnyShape,
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  camera: ProjectionCamera,
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  withHiddenLines = true
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): { visible: Edge[]; hidden: Edge[] } {
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  const oc = getOC();
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  const r = GCWithScope();
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  const hiddenLineRemoval = r(new oc.HLRBRep_Algo_1());
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  hiddenLineRemoval.Add_2(shape.wrapped, 0);
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  const projector = r(new oc.HLRAlgo_Projector_2(camera.wrapped));
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  hiddenLineRemoval.Projector_1(projector);
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  hiddenLineRemoval.Update();
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  hiddenLineRemoval.Hide_1();
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  const hlrShapes = new oc.HLRBRep_HLRToShape(
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    new oc.Handle_HLRBRep_Algo_2(hiddenLineRemoval)
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  );
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  const visible = [
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    ...getEdges(hlrShapes.VCompound_1()),
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    ...getEdges(hlrShapes.Rg1LineVCompound_1()),
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    ...getEdges(hlrShapes.OutLineVCompound_1()),
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  ];
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  visible.forEach((e) => oc.BRepLib.BuildCurves3d_2(e.wrapped));
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  const hidden = withHiddenLines
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    ? [
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        ...getEdges(hlrShapes.HCompound_1()),
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        ...getEdges(hlrShapes.Rg1LineHCompound_1()),
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        ...getEdges(hlrShapes.OutLineHCompound_1()),
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      ]
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    : [];
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  hidden.forEach((e) => oc.BRepLib.BuildCurves3d_2(e.wrapped));
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  return { visible, hidden };
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}
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