irrlicht/source/Irrlicht/CSceneNodeAnimatorFollowSpl...

134 lines
3.3 KiB
C++

// Copyright (C) 2002-2007 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h
#include "CSceneNodeAnimatorFollowSpline.h"
namespace irr
{
namespace scene
{
//! constructor
CSceneNodeAnimatorFollowSpline::CSceneNodeAnimatorFollowSpline(u32 time,
const core::array< core::vector3df >& points, f32 speed,
f32 tightness)
: Points(points), Speed(speed), Tightness(tightness), StartTime(time)
{
#ifdef _DEBUG
setDebugName("CSceneNodeAnimatorFollowSpline");
#endif
}
//! destructor
CSceneNodeAnimatorFollowSpline::~CSceneNodeAnimatorFollowSpline()
{
}
inline s32 CSceneNodeAnimatorFollowSpline::clamp(s32 idx, s32 size)
{
return ( idx<0 ? size+idx : ( idx>=size ? idx-size : idx ) );
}
//! animates a scene node
void CSceneNodeAnimatorFollowSpline::animateNode(ISceneNode* node, u32 timeMs)
{
core::vector3df p, p0, p1, p2, p3;
core::vector3df t1, t2;
const u32 pSize = Points.size();
const f32 dt = ( (timeMs-StartTime) * Speed * 0.001f );
const f32 u = core::fract ( dt );
s32 idx = core::floor32( dt ) % pSize;
//f32 u = 0.001f * fmodf( dt, 1000.0f );
p0 = Points[ clamp( idx - 1, pSize ) ];
p1 = Points[ clamp( idx + 0, pSize ) ];
p2 = Points[ clamp( idx + 1, pSize ) ];
p3 = Points[ clamp( idx + 2, pSize ) ];
// hermite polynomials
f32 h1 = 2.0f * u * u * u - 3.0f * u * u + 1.0f;
f32 h2 = -2.0f * u * u * u + 3.0f * u * u;
f32 h3 = u * u * u - 2.0f * u * u + u;
f32 h4 = u * u * u - u * u;
// tangents
t1 = ( p2 - p0 ) * Tightness;
t2 = ( p3 - p1 ) * Tightness;
// interpolated point
p = p1 * h1 + p2 * h2 + t1 * h3 + t2 * h4;
node->setPosition(p);
}
//! Writes attributes of the scene node animator.
void CSceneNodeAnimatorFollowSpline::serializeAttributes(io::IAttributes* out, io::SAttributeReadWriteOptions* options)
{
out->addFloat("Speed", Speed);
out->addFloat("Tightness", Tightness);
u32 count = Points.size();
if ( options && (options->Flags & io::EARWF_FOR_EDITOR))
{
// add one point in addition when serializing for editors
// to make it easier to add points quickly
count += 1;
}
for (u32 i=0; i<count; ++i)
{
core::stringc tname = "Point";
tname += (int)(i+1);
out->addVector3d(tname.c_str(), i<Points.size() ? Points[i] : core::vector3df(0,0,0) );
}
}
//! Reads attributes of the scene node animator.
void CSceneNodeAnimatorFollowSpline::deserializeAttributes(io::IAttributes* in, io::SAttributeReadWriteOptions* options)
{
Speed = in->getAttributeAsFloat("Speed");
Tightness = in->getAttributeAsFloat("Tightness");
Points.clear();
for(u32 i=1; true; ++i)
{
core::stringc pname = "Point";
pname += (int)i;
if (in->existsAttribute(pname.c_str()))
{
core::vector3df pos = in->getAttributeAsVector3d(pname.c_str());
Points.push_back(pos);
}
else
break;
}
// remove last point if double entry from editor
if ( options && (options->Flags & io::EARWF_FOR_EDITOR) &&
Points.size() > 2 && Points.getLast() == core::vector3df(0,0,0))
{
Points.erase(Points.size()-1);
if (Points.size() > 2 && Points.getLast() == core::vector3df(0,0,0))
Points.erase(Points.size()-1);
}
}
} // end namespace scene
} // end namespace irr