Matrix3f BSpline2f::frameAt( float t ) const
{
Vector2f p = evaluateAt( t );
Vector2f tangent = tangentAt( t ).normalized();
Vector2f normal = tangent.normal();
return Matrix3f
(
normal.x, tangent.x, p.x,
normal.y, tangent.y, p.y,
0, 0, 1
);
}
// static
std::vector< Vector2f > GeometryUtils::uniformSampleBoxAroundLineSegment( const Vector2f& p0, const Vector2f& p1,
float width, int nSamplesWidth, int nSamplesLength )
{
std::vector< Vector2f > samples( nSamplesWidth * nSamplesLength );
Vector2f unitLength = ( p1 - p0 ).normalized();
Vector2f unitWidth = unitLength.normal().normalized();
float sampleSpacingW = width / ( nSamplesWidth - 1 );
float sampleSpacingL = ( p1 - p0 ).norm() / ( nSamplesLength - 1 );
Vector2f origin = p0 - 0.5f * width * unitWidth;
for( int w = 0; w < nSamplesWidth; ++w )
{
for( int l = 0; l < nSamplesLength; ++l )
{
samples[ w * nSamplesLength + l ] =
origin + w * sampleSpacingW * unitWidth + l * sampleSpacingL * unitLength;
}
}
return samples;
}
