diff options
Diffstat (limited to 'kpovmodeler/pmsplinesegment.cpp')
| -rw-r--r-- | kpovmodeler/pmsplinesegment.cpp | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/kpovmodeler/pmsplinesegment.cpp b/kpovmodeler/pmsplinesegment.cpp new file mode 100644 index 00000000..dbbc6b18 --- /dev/null +++ b/kpovmodeler/pmsplinesegment.cpp @@ -0,0 +1,107 @@ +//-*-C++-*- +/* +************************************************************************** + description + -------------------- + copyright : (C) 2002 by Andreas Zehender + email : zehender@kde.org +************************************************************************** + +************************************************************************** +* * +* 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. * +* * +**************************************************************************/ + +#include "pmsplinesegment.h" + +PMVector PMSplineSegment::point( double t ) const +{ + double t2 = t * t; + double t3 = t2 * t; + + return PMVector( m_a[0]*t3 + m_b[0]*t2 + m_c[0]*t + m_d[0], + m_a[1]*t3 + m_b[1]*t2 + m_c[1]*t + m_d[1] ); +} + +PMVector PMSplineSegment::gradient( double t ) const +{ + double t2 = t * t; + + return PMVector( 3*m_a[0]*t2 + 2*m_b[0]*t + m_c[0], + 3*m_a[1]*t2 + 2*m_b[1]*t + m_c[1] ); +} + +void PMSplineSegment::calculateLinear( const PMVector& p1, const PMVector& p2 ) +{ + m_a[0] = 0.0; + m_b[0] = 0.0; + m_c[0] = -1.0 * p1[0] + 1.0 * p2[0]; + m_d[0] = 1.0 * p1[0]; + + m_a[1] = 0.0; + m_b[1] = 0.0; + m_c[1] = -1.0 * p1[1] + 1.0 * p2[1]; + m_d[1] = 1.0 * p1[1]; +} + +void PMSplineSegment::calculateQuadratic( const PMVector& p1, + const PMVector& p2, + const PMVector& p3 ) +{ + m_a[0] = 0.0; + m_b[0] = 0.5 * p1[0] - 1.0 * p2[0] + 0.5 * p3[0]; + m_c[0] = -0.5 * p1[0] + 0.5 * p3[0]; + m_d[0] = 1.0 * p2[0]; + + m_a[1] = 0.0; + m_b[1] = 0.5 * p1[1] - 1.0 * p2[1] + 0.5 * p3[1]; + m_c[1] = -0.5 * p1[1] + 0.5 * p3[1]; + m_d[1] = 1.0 * p2[1]; +} + +void PMSplineSegment::calculateCubic( const PMVector& p1, const PMVector& p2, + const PMVector& p3, const PMVector& p4 ) +{ + m_a[0] = -0.5 * p1[0] + 1.5 * p2[0] - 1.5 * p3[0] + 0.5 * p4[0]; + m_b[0] = p1[0] - 2.5 * p2[0] + 2.0 * p3[0] - 0.5 * p4[0]; + m_c[0] = -0.5 * p1[0] + 0.5 * p3[0]; + m_d[0] = p2[0]; + + m_a[1] = -0.5 * p1[1] + 1.5 * p2[1] - 1.5 * p3[1] + 0.5 * p4[1]; + m_b[1] = p1[1] - 2.5 * p2[1] + 2.0 * p3[1] - 0.5 * p4[1]; + m_c[1] = -0.5 * p1[1] + 0.5 * p3[1]; + m_d[1] = p2[1]; +} + +void PMSplineSegment::calculateBezier( const PMVector& p1, const PMVector& p2, + const PMVector& p3, const PMVector& p4 ) +{ + m_a[0] = - p1[0] + 3.0 * p2[0] - 3.0 * p3[0] + p4[0]; + m_b[0] = 3.0 * p1[0] - 6.0 * p2[0] + 3.0 * p3[0]; + m_c[0] = -3.0 * p1[0] + 3.0 * p2[0]; + m_d[0] = p1[0]; + + m_a[1] = - p1[1] + 3.0 * p2[1] - 3.0 * p3[1] + p4[1]; + m_b[1] = 3.0 * p1[1] - 6.0 * p2[1] + 3.0 * p3[1]; + m_c[1] = -3.0 * p1[1] + 3.0 * p2[1]; + m_d[1] = p1[1]; +} + +void PMSplineSegment::calculateQuadricBezier( const PMVector& p1, + const PMVector& p2, + const PMVector& p3 ) +{ + m_a[0] = 0; + m_b[0] = p1[0] - 2.0 * p2[0] + p3[0]; + m_c[0] = -2.0 * p1[0] + 2.0 * p2[0]; + m_d[0] = p1[0]; + + m_a[1] = 0; + m_b[1] = p1[1] - 2.0 * p2[1] + p3[1]; + m_c[1] = -2.0 * p1[1] + 2.0 * p2[1]; + m_d[1] = p1[1]; +} |