void Context::appendPath( const cinder::Path2d &path )
{
size_t point = 0;
if( path.empty() )
return;
moveTo( path.getPoint( point++ ) );
for( size_t seg = 0; seg < path.getNumSegments(); ++seg ) {
switch( path.getSegmentType( seg ) ) {
case Path2d::LINETO:
lineTo( path.getPoint( point++ ) );
break;
case Path2d::QUADTO: {
const Vec2f &spl0( path.getPoint( point - 1 ) ); const Vec2f &spl1( path.getPoint( point + 0 ) ); const Vec2f &spl2( path.getPoint( point + 1 ) );
curveTo( spl0 + (spl1 - spl0) / 3.0f * 2.0f, spl1 + (spl2 - spl1) / 3.0f, spl2 );
point += 2;
}
break;
case Path2d::CUBICTO:
curveTo( path.getPoint( point ), path.getPoint( point + 1 ), path.getPoint( point + 2 ) );
point += 3;
break;
case Path2d::CLOSE:
closePath();
break;
}
}
}
void Path2DSamplesApp::drawPath( const cinder::Path2d &path )
{
gl::color( Color( 1, 0 ,0 ) );
// draw path
gl::draw( path );
//draw points
gl::color( 1, 1, 0 );
for( int i = 0; i < path.getPoints().size(); i++ ) {
vec2 point = path.getPoint( i );
gl::drawSolidRect( Rectf( -2.0, -2.0, 2.0, 2.0 ) + point );
// gl::drawLine( path.getPosition( t ), mPath.getPosition( t ) + normalize( mPath.getTangent( t ) ) * 80.0f );
}
// draw point along the curve
gl::color( 1, 0, 1 );
float pos = ( getElapsedSeconds() * 0.25f );
pos -= floor( pos );
vec2 pt = path.getPosition( pos );
gl::drawSolidCircle( pt, 4.0 );
gl::drawLine( pt, pt + normalize(path.getTangent( pos )) * 25.0f );
gl::drawLine( pt, pt - normalize(path.getTangent( pos )) * 25.0f );
//
// gl::color( 0, 1, 1 );
// pt = path.getTangent( pos );
// gl::drawSolidCircle( pt, 4.0 );
//draw lines between points depending on their segment type
gl::color( 1, 0, 1 );
int ptCount = 0;
for( int i = 0; i < path.getSegments().size(); i++ ) {
auto segment = path.getSegments()[i];
// console() << " --- " << segment << " --- "<< endl;
auto points = path.getPoints();
// if segment type == Path2d::SegmentType::CUBICTO
// draw lines between
if( segment == Path2d::SegmentType::QUADTO ) {
vec2 pt1 = path.getPoints()[ptCount];
vec2 pt2 = path.getPoints()[ptCount + 1];
vec2 pt3 = path.getPoints()[ptCount + 2];
if( segment == Path2d::SegmentType::QUADTO ) {
gl::drawLine( pt1, pt2 );
gl::drawLine( pt2, pt3 );
}
}
if( segment == Path2d::SegmentType::CUBICTO ) {
vec2 pt1 = path.getPoints()[ptCount + 0];
vec2 pt2 = path.getPoints()[ptCount + 1];
vec2 pt3 = path.getPoints()[ptCount + 2];
vec2 pt4 = path.getPoints()[ptCount + 3];
gl::drawLine( pt1, pt2 );
gl::drawLine( pt3, pt4 );
}
// path.getSegmentTangent(size_t segment, float t)
// console() << segment << endl;
// vec2 point = path.getPoint( i );
// gl::drawSolidRect( Rectf( -2.0, -2.0, 2.0, 2.0 ) + point );
/*if( segment == Path2d::SegmentType::MOVETO || segment == Path2d::SegmentType::LINETO )
ptCount += 1;
if( segment == Path2d::SegmentType::CUBICTO )
ptCount += 3;
if( segment == Path2d::SegmentType::QUADTO )
ptCount += 2;*/
ptCount += path.sSegmentTypePointCounts[segment];
}
gl::color( 1, 1, 1, 0.2 );
// gl::drawSolidRect( path.calcBoundingBox() ); // box around everything (including points)
gl::drawSolidRect( path.calcPreciseBoundingBox() ); // box around just the path itself
// gl::drawStrokedRect(path.calcPreciseBoundingBox());
// calculate length of path
gl::drawString( "length: " + to_string( path.calcLength() ), vec2( 0.0, -10.0 ) );
// not sure what these do
/*static int calcQuadraticBezierMonotoneRegions( const vec2 p[3], float resultT[2] );
static vec2 calcQuadraticBezierPos( const vec2 p[3], float t );
static vec2 calcQuadraticBezierDerivative( const vec2 p[3], float t );
static int calcCubicBezierMonotoneRegions( const vec2 p[4], float resultT[4] );
static vec2 calcCubicBezierPos( const vec2 p[4], float t );
static vec2 calcCubicBezierDerivative( const vec2 p[4], float t );*/
{
gl::color( 0, 0, 0 );
// float time = path.calcNormalizedTime( getElapsedSeconds() * 0.25 ); // should this be used when getting position based on time?
float time = path.calcTimeForDistance( getElapsedSeconds() * 20.0 ); // distance based. so 100 is 100 pixels along the path. It loops. Returns a time
// console() << getElapsedSeconds() * 20.0 << " " << time << endl;
vec2 pos = path.getPosition( time );
gl::drawSolidCircle( pos, 2.0 );
}
// subdivides curves into points. You can construct a simplified curve that way
auto subdivided = path.subdivide( 0.1 );
for( auto d : subdivided ) {
gl::color( 0, 1, 1 );
gl::drawStrokedCircle( d, 3.0 );
}
// move over a bit and dot affine matric copies and rotate
{
gl::ScopedMatrices mtrx;
gl::translate( path.calcBoundingBox().getWidth(), 0 );
for( int i = 0; i < 8; i++ ){
MatrixAffine2<float> affineMtrx;
affineMtrx.scale( 0.25 );
affineMtrx.rotate( ( ( M_PI * 2) / 8 ) * i );
auto pathCopy = path.transformCopy( affineMtrx );
gl::draw( pathCopy );
}
}
//
//path.calcSegmentLength( segment number, min, max )
// highlight 0.25 - 0.75 or each segment
// path.getSegmentRelativeT(float t, size_t *segment, float *relativeT) // used internally when getting positions. tangents, etx
//path.segmentSolveTimeForDistance(size_t segment, float segmentLength, float segmentRelativeDistance, float tolerance, int maxIterations) // should use calcNormalizedTime or calcTimeForDistance
// Path2d article
// simple drawing
// drawing and adding points after
// drawing and then moving handles
// idea: draw path that then controls sound - pitch, volume, and other stuff - using the curve
}