void CreateTool::JitterInstanceOffsets( float instanceRadius, float maxJitter, V_Vector3& offsets )
{
V_Vector3 jitterVectors;
jitterVectors.push_back( Editor::UpVector );
jitterVectors.push_back( Editor::OutVector );
V_Vector3::iterator itr = offsets.begin();
V_Vector3::iterator end = offsets.end();
for ( ; itr != end; ++itr )
{
V_Vector3::const_iterator jitterItr = jitterVectors.begin();
V_Vector3::const_iterator jitterEnd = jitterVectors.end();
for ( ; jitterItr != jitterEnd; ++jitterItr )
{
int searchTries = 10;
while ( searchTries > 0 )
{
--searchTries;
float jitter = ( rand() / ( (float) RAND_MAX + 1.0f ) ) * 2.0f - 1.0f;
float randomNumber = rand() / ( (float) RAND_MAX + 1.0f );
float testNumber = GetNormalProbabilityFromPercent( jitter );
if ( randomNumber <= testNumber )
{
(*itr) += (*jitterItr) * jitter * maxJitter;
searchTries = 0;
}
}
}
}
}
static void MakeContinuous(V_Vector3& cvs)
{
// ensure continuity through to first and last cvs by creating new begin and end tagent cvs
Vector3 ab = cvs[0] - cvs[1];
cvs.insert(cvs.begin(), cvs[0] + ab);
Vector3 cd = cvs[ cvs.size() - 1 ] - cvs[ cvs.size() - 2 ];
cvs.push_back(cvs[ cvs.size() - 1 ] + cd);
}
static void MakeClosed(V_Vector3& cvs)
{
// synthisize a new knot from the last two and first two cvs
cvs.insert(cvs.begin(), cvs[cvs.size()-1]);
cvs.insert(cvs.begin(), cvs[cvs.size()-2]);
// this is 2 and 3 since we inserted @ 0 above
cvs.push_back(cvs[2]);
cvs.push_back(cvs[3]);
}
void CreateTool::RandomizeInstanceOffsets( V_Vector3& offsets )
{
V_Vector3 newOffsets;
newOffsets.reserve( offsets.size() );
while ( offsets.size() )
{
V_Vector3::iterator itr = offsets.begin() + ( rand() % offsets.size() );
newOffsets.push_back( *itr );
offsets.erase( itr );
}
V_Vector3::iterator itr = newOffsets.begin();
V_Vector3::iterator end = newOffsets.end();
for ( ; itr != end; ++itr )
{
offsets.push_back( *itr );
}
}
void AlignedBox::Transform(const Matrix4& matrix)
{
// get the currents sample bounds
V_Vector3 vertices;
GetVertices( vertices );
// reseed this box
Reset();
// iterate and resample the bounds
V_Vector3::iterator itr = vertices.begin();
V_Vector3::iterator end = vertices.end();
for ( ; itr != end; ++itr )
{
// transform the sample
matrix.TransformVertex( *itr );
// test the sample
Test( *itr );
}
}
void CreateTool::SelectInstanceOffsets( DistributionStyle style, float radius, V_Vector3& offsets )
{
V_Vector3 selectedOffsets;
selectedOffsets.reserve( offsets.size() );
V_Vector3::iterator itr = offsets.begin();
V_Vector3::iterator end = offsets.end();
for ( ; itr != end; ++itr )
{
switch ( style )
{
case DistributionStyles::Uniform:
{
float randomNumber = rand() / ( (float) RAND_MAX + 1.0f );
if ( randomNumber <= 0.5f )
{
selectedOffsets.push_back( *itr );
}
break;
}
case DistributionStyles::Linear:
{
float radiusPercent = (*itr).Length() / radius;
float randomNumber = rand() / ( (float) RAND_MAX + 1.0f );
float testNumber = 1.0f - radiusPercent;
if ( randomNumber <= testNumber )
{
selectedOffsets.push_back( *itr );
}
break;
}
case DistributionStyles::Normal:
{
float radiusPercent = (*itr).Length() / radius;
float randomNumber = rand() / ( (float) RAND_MAX + 1.0f );
float testNumber = GetNormalProbabilityFromPercent( radiusPercent );
if ( randomNumber <= testNumber )
{
selectedOffsets.push_back( *itr );
}
break;
}
case DistributionStyles::Constant:
default:
selectedOffsets.push_back( *itr );
break;
}
}
offsets.clear();
offsets.reserve( selectedOffsets.size() );
itr = selectedOffsets.begin();
end = selectedOffsets.end();
for ( ; itr != end; ++itr )
{
offsets.push_back( *itr );
}
}
