From aa7ff25decb259acf1c0f233990d9dfddf14a4d9 Mon Sep 17 00:00:00 2001
From: Tim Redfern <tim@getdrop.com>
Date: Sat, 20 Jan 2018 18:01:49 +0000
Subject: transform vectors before masking

---
 drawing/src/lineSegmenter.h |  3 +++
 drawing/src/ofApp.cpp       | 31 ++++++++++++++++++++++++++++++-
 drawing/src/ofApp.h         |  2 ++
 3 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/drawing/src/lineSegmenter.h b/drawing/src/lineSegmenter.h
index 5b2aab3..d858ba2 100644
--- a/drawing/src/lineSegmenter.h
+++ b/drawing/src/lineSegmenter.h
@@ -11,6 +11,9 @@ class lineSegmenter{
 			}
 		}
 		const vector <ofPolyline> &getSegments(int num,float coverage, float phase);
+		ofPolyline getPoly(){
+			return line;
+		}
 		void draw();
 		int size();
 	private:
diff --git a/drawing/src/ofApp.cpp b/drawing/src/ofApp.cpp
index 28bca20..70a9f00 100644
--- a/drawing/src/ofApp.cpp
+++ b/drawing/src/ofApp.cpp
@@ -7,7 +7,7 @@ vector<std::string> cmdnames={"moveTo","lineTo","curveTo","bezierTo","quadBezier
 //--------------------------------------------------------------
 void ofApp::setup(){
 	ofxSVG svg;
-	svg.load("haring.svg");
+	svg.load("bars.svg");
 	vector <ofPath> paths= svg.getPaths();
 
 	for (int i=0;i<paths.size();i++){
@@ -63,6 +63,14 @@ void ofApp::update(){
 	clipper.addPolylines(mask, ClipperLib::ptClip);
 }
 
+ofPolyline ofApp::polyLineTransform(const ofPolyline& poly, ofMatrix4x4 xform){
+	ofPolyline tempPoly;
+	for (auto& p:poly){
+		tempPoly.addVertex(ofVec3f(p)*xform);
+	}
+	return tempPoly;
+}
+
 
 
 //--------------------------------------------------------------	
@@ -75,6 +83,8 @@ void ofApp::draw(){
 
 	float phase=fmod(ofGetElapsedTimef()/2,1);
 
+	//transform points of segmenter before intersecting with mask
+
 	switch (mode){
 		case 0:{
 			for (auto shape=segmenters.begin();shape!=segmenters.end();shape++){
@@ -124,6 +134,25 @@ void ofApp::draw(){
 		    break;
 		}
 		case 3:{
+			vector <ofPolyline> shapes;
+			ofMatrix4x4 rm = ofMatrix4x4::newIdentityMatrix();
+			rm.translate(-600,-450,0);
+			rm.rotateRad(ofGetElapsedTimef(),0,0,1);
+			rm.translate(600,450,0);
+			for (auto& segment:segmenters){
+				shapes.push_back(polyLineTransform(segment.getPoly(),rm));
+			}
+			clipper.addPolylines(shapes,ClipperLib::ptSubject);
+			vector<ofPolyline> clipped = clipper.getClippedLines(ClipperLib::ctIntersection);
+			for (auto& clip: clipped)
+		    {
+		        clip.draw();
+		        segmentsdrawn++;
+		        pointsdrawn+=clip.size();
+		    }
+			break;
+		}
+		case 4:{
 			int w=ofRandom(1000);
 			segmenters[w%segmenters.size()].draw();
 			segmentsdrawn=1;
diff --git a/drawing/src/ofApp.h b/drawing/src/ofApp.h
index ae4c1a3..c63533a 100644
--- a/drawing/src/ofApp.h
+++ b/drawing/src/ofApp.h
@@ -32,6 +32,8 @@ class ofApp : public ofBaseApp{
 		void dragEvent(ofDragInfo dragInfo);
 		void gotMessage(ofMessage msg);
 
+		ofPolyline polyLineTransform(const ofPolyline& poly, ofMatrix4x4 xform);
+
 		vector <lineSegmenter> segmenters;
 		vector <ofPolyline> mask;
 		
-- 
cgit v1.2.3