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Diffstat (limited to 'source/blender/freestyle/intern/geometry/GridHelpers.h')
| -rw-r--r-- | source/blender/freestyle/intern/geometry/GridHelpers.h | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/source/blender/freestyle/intern/geometry/GridHelpers.h b/source/blender/freestyle/intern/geometry/GridHelpers.h new file mode 100644 index 00000000000..b079005c1b5 --- /dev/null +++ b/source/blender/freestyle/intern/geometry/GridHelpers.h @@ -0,0 +1,199 @@ +// +// Filename : GridHelpers.h +// Author(s) : Alexander Beels +// Purpose : Class to define a cell grid surrounding +// the projected image of a scene +// Date of creation : 2010-12-13 +// +/////////////////////////////////////////////////////////////////////////////// + + +// +// Copyright (C) : Please refer to the COPYRIGHT file distributed +// with this source distribution. +// +// This program is free software; you can redistribute it and/or +// modify it under the terms of the GNU General Public License +// as published by the Free Software Foundation; either version 2 +// of the License, or (at your option) any later version. +// +// This program 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 +// GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License +// along with this program; if not, write to the Free Software +// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. +// +/////////////////////////////////////////////////////////////////////////////// + +#ifndef GRIDHELPERS_H +#define GRIDHELPERS_H + +#include <vector> +#include "Polygon.h" +#include "../winged_edge/WEdge.h" +#include "FRS_freestyle.h" +#include "GeomUtils.h" + +namespace GridHelpers { + +/*! Computes the distance from a point P to a segment AB */ +template<class T> +T closestPointToSegment(const T& P, const T& A , const T& B, real& distance) { + T AB, AP, BP; + AB = B - A; + AP = P - A; + BP = P - B; + + real c1(AB * AP); + if (c1 <= 0) { + distance = AP.norm(); + return A; // A is closest point + } + + real c2(AB * AB); + if (c2 <= c1) { + distance = BP.norm(); + return B; // B is closest point + } + + real b = c1 / c2; + T Pb, PPb; + Pb = A + b * AB; + PPb = P - Pb; + + distance = PPb.norm(); + return Pb; // closest point lies on AB +} + +inline Vec3r closestPointOnPolygon(const Vec3r& point, const Polygon3r& poly) { + // First cast a ray from the point onto the polygon plane + // If the ray intersects the polygon, then the intersection point + // is the closest point on the polygon + real t, u, v; + if ( poly.rayIntersect(point, poly.getNormal(), t, u, v) ) { + return point + poly.getNormal() * t; + } + + // Otherwise, get the nearest point on each edge, and take the closest + real distance; + Vec3r closest = closestPointToSegment(point, poly.getVertices()[2], poly.getVertices()[0], distance); + for ( unsigned i = 0; i < 2; ++i ) { + real t; + Vec3r p = closestPointToSegment(point, poly.getVertices()[i], poly.getVertices()[i + 1], t); + if ( t < distance ) { + distance = t; + closest = p; + } + } + return closest; +} + +inline real distancePointToPolygon(const Vec3r& point, const Polygon3r& poly) { + // First cast a ray from the point onto the polygon plane + // If the ray intersects the polygon, then the intersection point + // is the closest point on the polygon + real t, u, v; + if ( poly.rayIntersect(point, poly.getNormal(), t, u, v) ) { + return t > 0.0 ? t : -t; + } + + // Otherwise, get the nearest point on each edge, and take the closest + real distance = GeomUtils::distPointSegment(point, poly.getVertices()[2], poly.getVertices()[0]); + for ( unsigned i = 0; i < 2; ++i ) { + real t = GeomUtils::distPointSegment(point, poly.getVertices()[i], poly.getVertices()[i + 1]); + if ( t < distance ) { + distance = t; + } + } + return distance; +} + +class Transform { +public: + virtual ~Transform () =0; + virtual Vec3r operator()(const Vec3r& point) const =0; +}; + +inline bool insideProscenium (const real proscenium[4], const Polygon3r& polygon) { + // N.B. The bounding box check is redundant for inserting occluders into + // cells, because the cell selection code in insertOccluders has already + // guaranteed that the bounding boxes will overlap. + // First check the viewport edges, since they are the easiest case + // Check if the bounding box is entirely outside the proscenium + Vec3r bbMin, bbMax; + polygon.getBBox(bbMin, bbMax); + if ( bbMax[0] < proscenium[0] + || bbMin[0] > proscenium[1] + || bbMax[1] < proscenium[2] + || bbMin[1] > proscenium[3] ) { + return false; + } + + Vec3r boxCenter(proscenium[0] + (proscenium[1] - proscenium[0]) / 2.0, proscenium[2] + (proscenium[3] - proscenium[2]) / 2.0, 0.0); + Vec3r boxHalfSize((proscenium[1] - proscenium[0]) / 2.0, (proscenium[3] - proscenium[2]) / 2.0, 1.0); + Vec3r triverts[3] = { Vec3r(polygon.getVertices()[0][0], polygon.getVertices()[0][1], 0.0), Vec3r(polygon.getVertices()[1][0], polygon.getVertices()[1][1], 0.0), Vec3r(polygon.getVertices()[2][0], polygon.getVertices()[2][1], 0.0) }; + return GeomUtils::overlapTriangleBox(boxCenter, boxHalfSize, triverts); +} + +inline vector<Vec3r> enumerateVertices(const vector<WOEdge*>& fedges) { + vector<Vec3r> points; + // Iterate over vertices, storing projections in points + for(vector<WOEdge*>::const_iterator woe=fedges.begin(), woend=fedges.end(); woe!=woend; woe++) { + points.push_back((*woe)->GetaVertex()->GetVertex()); + } + + return points; +} + +void getDefaultViewProscenium(real viewProscenium[4]); + +inline void expandProscenium (real proscenium[4], const Polygon3r& polygon) { + Vec3r bbMin, bbMax; + polygon.getBBox(bbMin, bbMax); + + const real epsilon = 1.0e-6; + + if ( bbMin[0] <= proscenium[0] ) { + proscenium[0] = bbMin[0] - epsilon; + } + + if ( bbMin[1] <= proscenium[2] ) { + proscenium[2] = bbMin[1] - epsilon; + } + + if ( bbMax[0] >= proscenium[1] ) { + proscenium[1] = bbMax[0] + epsilon; + } + + if ( bbMax[1] >= proscenium[3] ) { + proscenium[3] = bbMax[1] + epsilon; + } +} + +inline void expandProscenium (real proscenium[4], const Vec3r& point) { + const real epsilon = 1.0e-6; + + if ( point[0] <= proscenium[0] ) { + proscenium[0] = point[0] - epsilon; + } + + if ( point[1] <= proscenium[2] ) { + proscenium[2] = point[1] - epsilon; + } + + if ( point[0] >= proscenium[1] ) { + proscenium[1] = point[0] + epsilon; + } + + if ( point[1] >= proscenium[3] ) { + proscenium[3] = point[1] + epsilon; + } +} + +}; + +#endif // GRIDHELPERS_H + |