static FloatPointGraph::Polygon walkGraphAndExtractPolygon(FloatPointGraph::Node* startNode)
{
FloatPointGraph::Polygon outPoly;
FloatPointGraph::Node* currentNode = startNode;
FloatPointGraph::Node* previousNode = startNode;
do {
currentNode->visit();
FloatPoint currentVec(*previousNode - *currentNode);
currentVec.normalize();
// Walk the graph, at each node choosing the next non-visited
// point with the greatest internal angle.
FloatPointGraph::Node* nextNode = nullptr;
float nextNodeAngle = 0;
for (auto potentialNextNode : currentNode->nextPoints()) {
if (potentialNextNode == currentNode)
continue;
// If we can get back to the start, we should, ignoring the fact that we already visited it.
// Otherwise we'll head inside the shape.
if (potentialNextNode == startNode) {
nextNode = startNode;
break;
}
if (potentialNextNode->isVisited())
continue;
FloatPoint nextVec(*potentialNextNode - *currentNode);
nextVec.normalize();
float angle = acos(nextVec.dot(currentVec));
float crossZ = nextVec.x() * currentVec.y() - nextVec.y() * currentVec.x();
if (crossZ < 0)
angle = (2 * piFloat) - angle;
if (!nextNode || angle > nextNodeAngle) {
nextNode = potentialNextNode;
nextNodeAngle = angle;
}
}
// If we don't end up at a node adjacent to the starting node,
// something went wrong (there's probably a hole in the shape),
// so bail out. We'll use a bounding box instead.
if (!nextNode)
return FloatPointGraph::Polygon();
outPoly.append(std::make_pair(currentNode, nextNode));
previousNode = currentNode;
currentNode = nextNode;
} while (currentNode != startNode);
return outPoly;
}
int ofxGifEncoder::getClosestToGreenScreenPaletteColorIndex(){
ofLog() << "computing closest palete color";
float minDistance = 100000;
int closestIndex = 0;
ofVec3f greenScreenVec(greenScreenColor.r, greenScreenColor.g, greenScreenColor.b);
for (int i = 0; i < palette.size(); i++) {
ofVec3f currentVec(palette.at(i).r, palette.at(i).g, palette.at(i).b);
float currentDistance = currentVec.distance(greenScreenVec);
if (currentDistance < minDistance){
minDistance = currentDistance;
closestIndex = i;
}
}
return closestIndex;
}
