unproject_on_line

Author: Teseo Schneider

src/unproject_on_line.cpp

@@ -0,0 +1,75 @@
+#include <common.h>
+#include <npe.h>
+#include <typedefs.h>
+
+
+#include <igl/unproject_on_line.h>
+
+const char *ds_unproject_on_line = R"igl_Qu8mg5v7(
+
+
+Given a screen space point (u,v) and the current projection matrix (e.g.
+gl_proj * gl_modelview) and viewport, _unproject_ the point into the scene
+so that it lies on given line (origin and dir) and projects as closely as
+possible to the given screen space point.
+
+Parameters
+----------
+UV  2-long uv-coordinates of screen space point
+M  4 by 4 projection matrix
+VP  4-long viewport: (corner_u, corner_v, width, height)
+origin  point on line
+dir  vector parallel to line
+
+Returns
+-------
+t  line parameter so that closest poin on line to viewer ray through UV
+       lies at origin+t*dir
+Z  3d position of closest point on line to viewing ray through UV
+
+See also
+--------
+
+
+Notes
+-----
+None
+
+Examples
+--------
+
+)igl_Qu8mg5v7";
+
+npe_function(unproject_on_line)
+npe_doc(ds_unproject_on_line)
+
+npe_arg(uv, dense_float, dense_double)
+npe_arg(m, npe_matches(uv))
+npe_arg(vp, npe_matches(uv))
+npe_arg(origin, npe_matches(uv))
+npe_arg(dir, npe_matches(uv))
+
+
+npe_begin_code()
+  assert_size_equals(uv, 2, "uv");
+  assert_rows_equals(m, 4, "m");
+  assert_cols_equals(m, 4, "m");
+  assert_size_equals(vp, 4, "uv");
+
+  assert_size_equals(origin, 3, "origin");
+  assert_size_equals(dir, 3, "dir");
+
+  EigenDense<npe_Scalar_uv> uv_copy = uv;
+  EigenDense<npe_Scalar_uv> m_copy = m;
+  EigenDense<npe_Scalar_uv> vp_copy = vp;
+  EigenDense<npe_Scalar_uv> origin_copy = origin;
+  EigenDense<npe_Scalar_uv> dir_copy = dir;
+
+  npe_Scalar_uv t;
+  igl::unproject_on_line(uv_copy, m_copy, vp_copy, origin_copy, dir_copy, t);
+  npe_Matrix_uv Z = origin + dir * t;
+
+  return std::make_tuple(double(t), npe::move(Z));
+
+npe_end_code()
+