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Edit File: utilities.3d.html
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>R: Utility functions for 3-D plots</title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <link rel="stylesheet" type="text/css" href="R.css" /> </head><body> <table width="100%" summary="page for G_utilities.3d {lattice}"><tr><td>G_utilities.3d {lattice}</td><td style="text-align: right;">R Documentation</td></tr></table> <h2> Utility functions for 3-D plots </h2> <h3>Description</h3> <p>These are (related to) the default panel functions for <code>cloud</code> and <code>wireframe</code>. </p> <h3>Usage</h3> <pre> ltransform3dMatrix(screen, R.mat) ltransform3dto3d(x, R.mat, dist) </pre> <h3>Arguments</h3> <table summary="R argblock"> <tr valign="top"><td><code>x</code></td> <td> <p><code>x</code> can be a numeric matrix with 3 rows for <code>ltransform3dto3d</code> </p> </td></tr> <tr valign="top"><td><code>screen</code></td> <td> <p>list, as described in <code><a href="panel.cloud.html">panel.cloud</a></code></p> </td></tr> <tr valign="top"><td><code>R.mat</code></td> <td> <p>4x4 transformation matrix in homogeneous coordinates</p> </td></tr> <tr valign="top"><td><code>dist</code></td> <td> <p>controls transformation to account for perspective viewing</p> </td></tr> </table> <h3>Details</h3> <p><code>ltransform3dMatrix</code> and <code>ltransform3dto3d</code> are utility functions to help in computation of projections. These functions are used inside the panel functions for <code>cloud</code> and <code>wireframe</code>. They may be useful in user-defined panel functions as well. </p> <p>The first function takes a list of the form of the <code>screen</code> argument in <code>cloud</code> and <code>wireframe</code> and a <code>R.mat</code>, a 4x4 transformation matrix in homogeneous coordinates, to return a new 4x4 transformation matrix that is the result of applying <code>R.mat</code> followed by the rotations in <code>screen</code>. The second function applies a 4x4 transformation matrix in homogeneous coordinates to a 3xn matrix representing points in 3-D space, and optionally does some perspective computations. (There has been no testing with non-trivial transformation matrices, and my knowledge of the homogeneous coordinate system is very limited, so there may be bugs here.) </p> <h3>Author(s)</h3> <p> Deepayan Sarkar <a href="mailto:Deepayan.Sarkar@R-project.org">Deepayan.Sarkar@R-project.org</a></p> <h3>See Also</h3> <p><code><a href="cloud.html">cloud</a></code>, <code><a href="panel.cloud.html">panel.cloud</a></code></p> <hr /><div style="text-align: center;">[Package <em>lattice</em> version 0.20-38 <a href="00Index.html">Index</a>]</div> </body></html>