quadrilateralcowboy/idlib/geometry/Surface_SweptSpline.cpp

224 lines
6.7 KiB
C++

/*
===========================================================================
Doom 3 GPL Source Code
Copyright (C) 1999-2011 id Software LLC, a ZeniMax Media company.
This file is part of the Doom 3 GPL Source Code (?Doom 3 Source Code?).
Doom 3 Source Code 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 3 of the License, or
(at your option) any later version.
Doom 3 Source Code 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 Doom 3 Source Code. If not, see <http://www.gnu.org/licenses/>.
In addition, the Doom 3 Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the Doom 3 Source Code. If not, please request a copy in writing from id Software at the address below.
If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.
===========================================================================
*/
#include "../precompiled.h"
#pragma hdrstop
/*
====================
idSurface_SweptSpline::SetSpline
====================
*/
void idSurface_SweptSpline::SetSpline( idCurve_Spline<idVec4> *spline ) {
if ( this->spline ) {
delete this->spline;
}
this->spline = spline;
}
/*
====================
idSurface_SweptSpline::SetSweptSpline
====================
*/
void idSurface_SweptSpline::SetSweptSpline( idCurve_Spline<idVec4> *sweptSpline ) {
if ( this->sweptSpline ) {
delete this->sweptSpline;
}
this->sweptSpline = sweptSpline;
}
/*
====================
idSurface_SweptSpline::SetSweptCircle
Sets the swept spline to a NURBS circle.
====================
*/
void idSurface_SweptSpline::SetSweptCircle( const float radius ) {
idCurve_NURBS<idVec4> *nurbs = new idCurve_NURBS<idVec4>();
nurbs->Clear();
nurbs->AddValue( 0.0f, idVec4( radius, radius, 0.0f, 0.00f ) );
nurbs->AddValue( 100.0f, idVec4( -radius, radius, 0.0f, 0.25f ) );
nurbs->AddValue( 200.0f, idVec4( -radius, -radius, 0.0f, 0.50f ) );
nurbs->AddValue( 300.0f, idVec4( radius, -radius, 0.0f, 0.75f ) );
nurbs->SetBoundaryType( idCurve_NURBS<idVec4>::BT_CLOSED );
nurbs->SetCloseTime( 100.0f );
if ( sweptSpline ) {
delete sweptSpline;
}
sweptSpline = nurbs;
}
/*
====================
idSurface_SweptSpline::GetFrame
====================
*/
void idSurface_SweptSpline::GetFrame( const idMat3 &previousFrame, const idVec3 dir, idMat3 &newFrame ) {
float wx, wy, wz;
float xx, yy, yz;
float xy, xz, zz;
float x2, y2, z2;
float a, c, s, x, y, z;
idVec3 d, v;
idMat3 axis;
d = dir;
d.Normalize();
v = d.Cross( previousFrame[2] );
v.Normalize();
a = idMath::ACos( previousFrame[2] * d ) * 0.5f;
c = idMath::Cos( a );
s = idMath::Sqrt( 1.0f - c * c );
x = v[0] * s;
y = v[1] * s;
z = v[2] * s;
x2 = x + x;
y2 = y + y;
z2 = z + z;
xx = x * x2;
xy = x * y2;
xz = x * z2;
yy = y * y2;
yz = y * z2;
zz = z * z2;
wx = c * x2;
wy = c * y2;
wz = c * z2;
axis[0][0] = 1.0f - ( yy + zz );
axis[0][1] = xy - wz;
axis[0][2] = xz + wy;
axis[1][0] = xy + wz;
axis[1][1] = 1.0f - ( xx + zz );
axis[1][2] = yz - wx;
axis[2][0] = xz - wy;
axis[2][1] = yz + wx;
axis[2][2] = 1.0f - ( xx + yy );
newFrame = previousFrame * axis;
newFrame[2] = dir;
newFrame[2].Normalize();
newFrame[1].Cross( newFrame[ 2 ], newFrame[ 0 ] );
newFrame[1].Normalize();
newFrame[0].Cross( newFrame[ 1 ], newFrame[ 2 ] );
newFrame[0].Normalize();
}
/*
====================
idSurface_SweptSpline::Tessellate
tesselate the surface
====================
*/
void idSurface_SweptSpline::Tessellate( const int splineSubdivisions, const int sweptSplineSubdivisions ) {
int i, j, offset, baseOffset, splineDiv, sweptSplineDiv;
int i0, i1, j0, j1;
float totalTime, t;
idVec4 splinePos, splineD1;
idMat3 splineMat;
if ( !spline || !sweptSpline ) {
idSurface::Clear();
return;
}
verts.SetNum( splineSubdivisions * sweptSplineSubdivisions, false );
// calculate the points and first derivatives for the swept spline
totalTime = sweptSpline->GetTime( sweptSpline->GetNumValues() - 1 ) - sweptSpline->GetTime( 0 ) + sweptSpline->GetCloseTime();
sweptSplineDiv = sweptSpline->GetBoundaryType() == idCurve_Spline<idVec3>::BT_CLOSED ? sweptSplineSubdivisions : sweptSplineSubdivisions - 1;
baseOffset = (splineSubdivisions-1) * sweptSplineSubdivisions;
for ( i = 0; i < sweptSplineSubdivisions; i++ ) {
t = totalTime * i / sweptSplineDiv;
splinePos = sweptSpline->GetCurrentValue( t );
splineD1 = sweptSpline->GetCurrentFirstDerivative( t );
verts[baseOffset+i].xyz = splinePos.ToVec3();
verts[baseOffset+i].st[0] = splinePos.w;
verts[baseOffset+i].tangents[0] = splineD1.ToVec3();
}
// sweep the spline
totalTime = spline->GetTime( spline->GetNumValues() - 1 ) - spline->GetTime( 0 ) + spline->GetCloseTime();
splineDiv = spline->GetBoundaryType() == idCurve_Spline<idVec3>::BT_CLOSED ? splineSubdivisions : splineSubdivisions - 1;
splineMat.Identity();
for ( i = 0; i < splineSubdivisions; i++ ) {
t = totalTime * i / splineDiv;
splinePos = spline->GetCurrentValue( t );
splineD1 = spline->GetCurrentFirstDerivative( t );
GetFrame( splineMat, splineD1.ToVec3(), splineMat );
offset = i * sweptSplineSubdivisions;
for ( j = 0; j < sweptSplineSubdivisions; j++ ) {
idDrawVert *v = &verts[offset+j];
v->xyz = splinePos.ToVec3() + verts[baseOffset+j].xyz * splineMat;
v->st[0] = verts[baseOffset+j].st[0];
v->st[1] = splinePos.w;
v->tangents[0] = verts[baseOffset+j].tangents[0] * splineMat;
v->tangents[1] = splineD1.ToVec3();
v->normal = v->tangents[1].Cross( v->tangents[0] );
v->normal.Normalize();
v->color[0] = v->color[1] = v->color[2] = v->color[3] = 0;
}
}
indexes.SetNum( splineDiv * sweptSplineDiv * 2 * 3, false );
// create indexes for the triangles
for ( offset = i = 0; i < splineDiv; i++ ) {
i0 = (i+0) * sweptSplineSubdivisions;
i1 = (i+1) % splineSubdivisions * sweptSplineSubdivisions;
for ( j = 0; j < sweptSplineDiv; j++ ) {
j0 = (j+0);
j1 = (j+1) % sweptSplineSubdivisions;
indexes[offset++] = i0 + j0;
indexes[offset++] = i0 + j1;
indexes[offset++] = i1 + j1;
indexes[offset++] = i1 + j1;
indexes[offset++] = i1 + j0;
indexes[offset++] = i0 + j0;
}
}
GenerateEdgeIndexes();
}