+++ /dev/null
-/* -*- C++ -*- ------------------------------------------------------------
-
-Copyright (c) 2007 Jesse Anders and Demian Nave http://cmldev.net/
-
-The Configurable Math Library (CML) is distributed under the terms of the
-Boost Software License, v1.0 (see cml/LICENSE for details).
-
- *-----------------------------------------------------------------------*/
-/** @file
- * @brief
- */
-
-#ifndef frustum_h
-#define frustum_h
-
-#include <cml/mathlib/matrix_concat.h>
-#include <cml/mathlib/checking.h>
-
-namespace cml {
-
-/* @todo: plane class, and perhaps named arguments instead of an array. */
-
-/* Extract the planes of a frustum given a modelview matrix and a projection
- * matrix with the given near z-clipping range. The planes are normalized by
- * default, but this can be turned off with the 'normalize' argument.
- *
- * The planes are in ax+by+cz+d = 0 form, and are in the order:
- * left
- * right
- * bottom
- * top
- * near
- * far
- */
-
-template < class MatT, typename Real > void
-extract_frustum_planes(
- const MatT& modelview,
- const MatT& projection,
- Real planes[6][4],
- ZClip z_clip,
- bool normalize = true)
-{
- extract_frustum_planes(
- detail::matrix_concat_transforms_4x4(modelview,projection),
- planes,
- z_clip,
- normalize
- );
-}
-
-/* Extract the planes of a frustum from a single matrix assumed to contain any
- * model and view transforms followed by a projection transform with the given
- * near z-cliping range. The planes are normalized by default, but this can be
- * turned off with the 'normalize' argument.
- *
- * The planes are in ax+by+cz+d = 0 form, and are in the order:
- * left
- * right
- * bottom
- * top
- * near
- * far
- */
-
-template < class MatT, typename Real > void
-extract_frustum_planes(
- const MatT& m,
- Real planes[6][4],
- ZClip z_clip,
- bool normalize = true)
-{
- detail::CheckMatHomogeneous3D(m);
-
- /* Left: [03+00, 13+10, 23+20, 33+30] */
-
- planes[0][0] = m.basis_element(0,3) + m.basis_element(0,0);
- planes[0][1] = m.basis_element(1,3) + m.basis_element(1,0);
- planes[0][2] = m.basis_element(2,3) + m.basis_element(2,0);
- planes[0][3] = m.basis_element(3,3) + m.basis_element(3,0);
-
- /* Right: [03-00, 13-10, 23-20, 33-30] */
-
- planes[1][0] = m.basis_element(0,3) - m.basis_element(0,0);
- planes[1][1] = m.basis_element(1,3) - m.basis_element(1,0);
- planes[1][2] = m.basis_element(2,3) - m.basis_element(2,0);
- planes[1][3] = m.basis_element(3,3) - m.basis_element(3,0);
-
- /* Bottom: [03+01, 13+11, 23+21, 33+31] */
-
- planes[2][0] = m.basis_element(0,3) + m.basis_element(0,1);
- planes[2][1] = m.basis_element(1,3) + m.basis_element(1,1);
- planes[2][2] = m.basis_element(2,3) + m.basis_element(2,1);
- planes[2][3] = m.basis_element(3,3) + m.basis_element(3,1);
-
- /* Top: [03-01, 13-11, 23-21, 33-31] */
-
- planes[3][0] = m.basis_element(0,3) - m.basis_element(0,1);
- planes[3][1] = m.basis_element(1,3) - m.basis_element(1,1);
- planes[3][2] = m.basis_element(2,3) - m.basis_element(2,1);
- planes[3][3] = m.basis_element(3,3) - m.basis_element(3,1);
-
- /* Far: [03-02, 13-12, 23-22, 33-32] */
-
- planes[5][0] = m.basis_element(0,3) - m.basis_element(0,2);
- planes[5][1] = m.basis_element(1,3) - m.basis_element(1,2);
- planes[5][2] = m.basis_element(2,3) - m.basis_element(2,2);
- planes[5][3] = m.basis_element(3,3) - m.basis_element(3,2);
-
- /* Near: [03+02, 13+12, 23+22, 33+32] : [02, 12, 22, 32] */
- extract_near_frustum_plane(m, planes[4], z_clip);
-
- /* @todo: This will be handled by the plane class */
- if (normalize) {
- for (size_t i = 0; i < 6; ++i) {
- Real invl = inv_sqrt(planes[i][0] * planes[i][0] +
- planes[i][1] * planes[i][1] +
- planes[i][2] * planes[i][2]);
-
- planes[i][0] *= invl;
- planes[i][1] *= invl;
- planes[i][2] *= invl;
- planes[i][3] *= invl;
- }
- }
-}
-
-/** Extract the near plane of a frustum given a concatenated modelview and
- * projection matrix with the given near z-clipping range. The plane is
- * not normalized.
- *
- * @note The plane is in ax+by+cz+d = 0 form.
- *
- * @warning The matrix is assumed to be a homogeneous transformation
- * matrix.
- */
-template < class MatT, class PlaneT > void
-extract_near_frustum_plane(
- const MatT& m,
- PlaneT& plane,
- ZClip z_clip
- )
-{
- /* Near: [03+02, 13+12, 23+22, 33+32] : [02, 12, 22, 32] */
- if (z_clip == z_clip_neg_one) {
- plane[0] = m.basis_element(0,3) + m.basis_element(0,2);
- plane[1] = m.basis_element(1,3) + m.basis_element(1,2);
- plane[2] = m.basis_element(2,3) + m.basis_element(2,2);
- plane[3] = m.basis_element(3,3) + m.basis_element(3,2);
- } else { // z_clip == z_clip_zero
- plane[0] = m.basis_element(0,2);
- plane[1] = m.basis_element(1,2);
- plane[2] = m.basis_element(2,2);
- plane[3] = m.basis_element(3,2);
- }
-}
-
-namespace detail {
-
-/* This is currently only in support of finding the corners of a frustum.
- * The input planes are assumed to have a single unique intersection, so
- * no tolerance is used.
- */
-
-template < typename Real > vector< Real, fixed<3> >
-intersect_planes(Real p1[4], Real p2[4], Real p3[4])
-{
- typedef vector< Real, fixed<3> > vector_type;
- typedef typename vector_type::value_type value_type;
-
- vector_type n1(p1[0],p1[1],p1[2]);
- vector_type n2(p2[0],p2[1],p2[2]);
- vector_type n3(p3[0],p3[1],p3[2]);
-
- value_type d1 = -p1[3];
- value_type d2 = -p2[3];
- value_type d3 = -p3[3];
-
- vector_type numer =
- d1*cross(n2,n3) + d2*cross(n3,n1) + d3*cross(n1,n2);
- value_type denom = triple_product(n1,n2,n3);
- return numer/denom;
-}
-
-} // namespace detail
-
-/* Get the corners of a frustum defined by 6 planes. The planes are in
- * ax+by+cz+d = 0 form, and are in the order:
- * left
- * right
- * bottom
- * top
- * near
- * far
- *
- * The corners are in CCW order starting in the lower-left, first at the near
- * plane, then at the far plane.
- */
-
-template < typename Real, typename E, class A > void
-get_frustum_corners(Real planes[6][4], vector<E,A> corners[8])
-{
- // NOTE: Prefixed with 'PLANE_' due to symbol conflict with Windows
- // macros PLANE_LEFT and PLANE_RIGHT.
- enum {
- PLANE_LEFT,
- PLANE_RIGHT,
- PLANE_BOTTOM,
- PLANE_TOP,
- PLANE_NEAR,
- PLANE_FAR
- };
-
- corners[0] = detail::intersect_planes(
- planes[PLANE_LEFT],
- planes[PLANE_BOTTOM],
- planes[PLANE_NEAR]
- );
- corners[1] = detail::intersect_planes(
- planes[PLANE_RIGHT],
- planes[PLANE_BOTTOM],
- planes[PLANE_NEAR]
- );
- corners[2] = detail::intersect_planes(
- planes[PLANE_RIGHT],
- planes[PLANE_TOP],
- planes[PLANE_NEAR]
- );
- corners[3] = detail::intersect_planes(
- planes[PLANE_LEFT],
- planes[PLANE_TOP],
- planes[PLANE_NEAR]
- );
- corners[4] = detail::intersect_planes(
- planes[PLANE_LEFT],
- planes[PLANE_BOTTOM],
- planes[PLANE_FAR]
- );
- corners[5] = detail::intersect_planes(
- planes[PLANE_RIGHT],
- planes[PLANE_BOTTOM],
- planes[PLANE_FAR]
- );
- corners[6] = detail::intersect_planes(
- planes[PLANE_RIGHT],
- planes[PLANE_TOP],
- planes[PLANE_FAR]
- );
- corners[7] = detail::intersect_planes(
- planes[PLANE_LEFT],
- planes[PLANE_TOP],
- planes[PLANE_FAR]
- );
-}
-
-} // namespace cml
-
-#endif
projects / chaz / yoink / blobdiff