diff -r ab77deb851fa -r 8d98ee0dc917 src/editmodes/circleMode.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/editmodes/circleMode.cpp	Tue Mar 03 22:29:27 2015 +0200
@@ -0,0 +1,315 @@
+/*
+ *  LDForge: LDraw parts authoring CAD
+ *  Copyright (C) 2013 - 2015 Teemu Piippo
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <QPainter>
+#include "circleMode.h"
+#include "../miscallenous.h"
+#include "../ldObject.h"
+#include "../ldDocument.h"
+#include "../ringFinder.h"
+#include "../primitives.h"
+#include "../glRenderer.h"
+#include "../mainWindow.h"
+#include "../ldObjectMath.h"
+
+CircleMode::CircleMode (GLRenderer* renderer) :
+	Super (renderer) {}
+
+EditModeType CircleMode::type() const
+{
+	return EditModeType::Circle;
+}
+
+double CircleMode::getCircleDrawDist (int pos) const
+{
+	assert (m_drawedVerts.size() >= pos + 1);
+	Vertex v1 = (m_drawedVerts.size() >= pos + 2) ? m_drawedVerts[pos + 1] :
+		renderer()->coordconv2_3 (renderer()->mousePosition(), false);
+	Axis localx, localy;
+	renderer()->getRelativeAxes (localx, localy);
+	double dx = m_drawedVerts[0][localx] - v1[localx];
+	double dy = m_drawedVerts[0][localy] - v1[localy];
+	return Grid::Snap (sqrt ((dx * dx) + (dy * dy)), Grid::Coordinate);
+}
+
+Matrix CircleMode::getCircleDrawMatrix (double scale)
+{
+	// Matrix templates. 2 is substituted with the scale value, 1 is inverted to -1 if needed.
+	static const Matrix templates[3] =
+	{
+		{ 2, 0, 0, 0, 1, 0, 0, 0, 2 },
+		{ 2, 0, 0, 0, 0, 2, 0, 1, 0 },
+		{ 0, 1, 0, 2, 0, 0, 0, 0, 2 },
+	};
+
+	Matrix transform = templates[renderer()->camera() % 3];
+
+	for (int i = 0; i < 9; ++i)
+	{
+		if (transform[i] == 2)
+			transform[i] = scale;
+		elif (transform[i] == 1 and renderer()->camera() >= 3)
+			transform[i] = -1;
+	}
+
+	return transform;
+}
+
+void CircleMode::buildCircle()
+{
+	LDObjectList objs;
+	const int segments (g_win->ringToolSegments());
+	const int divisions (g_win->ringToolHiRes() ? HighResolution : LowResolution);
+	double dist0 (getCircleDrawDist (0));
+	double dist1 (getCircleDrawDist (1));
+	LDDocumentPtr refFile;
+	Matrix transform;
+	bool circleOrDisc = false;
+
+	if (dist1 < dist0)
+		qSwap (dist0, dist1);
+
+	if (dist0 == dist1)
+	{
+		// If the radii are the same, there's no ring space to fill. Use a circle.
+		refFile = GetPrimitive (::Circle, segments, divisions, 0);
+		transform = getCircleDrawMatrix (dist0);
+		circleOrDisc = true;
+	}
+	elif (dist0 == 0 or dist1 == 0)
+	{
+		// If either radii is 0, use a disc.
+		refFile = GetPrimitive (::Disc, segments, divisions, 0);
+		transform = getCircleDrawMatrix ((dist0 != 0) ? dist0 : dist1);
+		circleOrDisc = true;
+	}
+	elif (g_RingFinder.findRings (dist0, dist1))
+	{
+		// The ring finder found a solution, use that. Add the component rings to the file.
+		for (const RingFinder::Component& cmp : g_RingFinder.bestSolution()->getComponents())
+		{
+			refFile = GetPrimitive (::Ring, segments, divisions, cmp.num);
+			LDSubfilePtr ref = LDSpawn<LDSubfile>();
+			ref->setFileInfo (refFile);
+			ref->setTransform (getCircleDrawMatrix (cmp.scale));
+			ref->setPosition (m_drawedVerts[0]);
+			ref->setColor (MainColor());
+			objs << ref;
+		}
+	}
+	else
+	{
+		// Ring finder failed, last resort: draw the ring with quads
+		QList<QLineF> c0, c1;
+		Axis localx, localy, localz;
+		renderer()->getRelativeAxes (localx, localy);
+		localz = (Axis) (3 - localx - localy);
+		double x0 (m_drawedVerts[0][localx]);
+		double y0 (m_drawedVerts[0][localy]);
+
+		Vertex templ;
+		templ.setCoordinate (localx, x0);
+		templ.setCoordinate (localy, y0);
+		templ.setCoordinate (localz, renderer()->getDepthValue());
+
+		// Calculate circle coords
+		MakeCircle (segments, divisions, dist0, c0);
+		MakeCircle (segments, divisions, dist1, c1);
+
+		for (int i = 0; i < segments; ++i)
+		{
+			Vertex v0, v1, v2, v3;
+			v0 = v1 = v2 = v3 = templ;
+			v0.setCoordinate (localx, v0[localx] + c0[i].x1());
+			v0.setCoordinate (localy, v0[localy] + c0[i].y1());
+			v1.setCoordinate (localx, v1[localx] + c0[i].x2());
+			v1.setCoordinate (localy, v1[localy] + c0[i].y2());
+			v2.setCoordinate (localx, v2[localx] + c1[i].x2());
+			v2.setCoordinate (localy, v2[localy] + c1[i].y2());
+			v3.setCoordinate (localx, v3[localx] + c1[i].x1());
+			v3.setCoordinate (localy, v3[localy] + c1[i].y1());
+
+			LDQuadPtr quad (LDSpawn<LDQuad> (v0, v1, v2, v3));
+			quad->setColor (MainColor());
+
+			// Ensure the quads always are BFC-front towards the camera
+			if (renderer()->camera() % 3 <= 0)
+				quad->invert();
+
+			objs << quad;
+		}
+	}
+
+	if (circleOrDisc and refFile != null)
+	{
+		LDSubfilePtr ref = LDSpawn<LDSubfile>();
+		ref->setFileInfo (refFile);
+		ref->setTransform (transform);
+		ref->setPosition (m_drawedVerts[0]);
+		ref->setColor (MainColor());
+		objs << ref;
+	}
+
+	unless (objs.isEmpty())
+	{
+		Axis relZ = renderer()->getRelativeZ();;
+		const int l (relZ == X ? 1 : 0);
+		const int m (relZ == Y ? 1 : 0);
+		const int n (relZ == Z ? 1 : 0);
+		RotateObjects (l, m, n, -m_angleOffset, objs);
+	}
+
+	finishDraw (objs);
+}
+
+double CircleMode::getAngleOffset() const
+{
+	if (m_drawedVerts.isEmpty())
+		return 0.0;
+
+	const int divisions (g_win->ringToolHiRes() ? HighResolution : LowResolution);
+	QPointF originspot (renderer()->coordconv3_2 (m_drawedVerts.first()));
+	QLineF bearing (originspot, renderer()->mousePositionF());
+	QLineF bearing2 (originspot, QPointF (originspot.x(), 0.0));
+	double angleoffset (-bearing.angleTo (bearing2) + 90);
+	angleoffset /= (360.0 / divisions); // convert angle to 0-16 scale
+	angleoffset = round (angleoffset); // round to nearest 16th
+	angleoffset *= ((2 * Pi) / divisions); // convert to radians
+	angleoffset *= renderer()->depthNegateFactor(); // negate based on camera
+	return angleoffset;
+}
+
+void CircleMode::render (QPainter& painter) const
+{
+	QFontMetrics metrics = QFontMetrics (QFont());
+
+	// If we have not specified the center point of the circle yet, preview it on the screen.
+	if (m_drawedVerts.isEmpty())
+	{
+		renderer()->drawBlip (painter, renderer()->coordconv3_2 (renderer()->position3D()));
+		return;
+	}
+
+	QVector<Vertex> innerverts, outerverts;
+	QVector<QPointF> innerverts2d, outerverts2d;
+	const double innerdistance (getCircleDrawDist (0));
+	const double outerdistance (m_drawedVerts.size() >= 2 ? getCircleDrawDist (1) : -1);
+	const int divisions (g_win->ringToolHiRes() ? HighResolution : LowResolution);
+	const int segments (g_win->ringToolSegments());
+	const double angleUnit (2 * Pi / divisions);
+	Axis relX, relY;
+	renderer()->getRelativeAxes (relX, relY);
+	const double angleoffset (m_drawedVerts.size() < 3 ? getAngleOffset() : m_angleOffset);
+
+	// Calculate the preview positions of vertices
+	for (int i = 0; i < segments + 1; ++i)
+	{
+		const double sinangle (sin (angleoffset + i * angleUnit));
+		const double cosangle (cos (angleoffset + i * angleUnit));
+		Vertex v (Origin);
+		v.setCoordinate (relX, m_drawedVerts[0][relX] + (cosangle * innerdistance));
+		v.setCoordinate (relY, m_drawedVerts[0][relY] + (sinangle * innerdistance));
+		innerverts << v;
+		innerverts2d << renderer()->coordconv3_2 (v);
+
+		if (outerdistance != -1)
+		{
+			v.setCoordinate (relX, m_drawedVerts[0][relX] + (cosangle * outerdistance));
+			v.setCoordinate (relY, m_drawedVerts[0][relY] + (sinangle * outerdistance));
+			outerverts << v;
+			outerverts2d << renderer()->coordconv3_2 (v);
+		}
+	}
+
+	QVector<QLineF> lines (segments);
+
+	if (outerdistance != -1 and outerdistance != innerdistance)
+	{
+		painter.setBrush (m_polybrush);
+		painter.setPen (Qt::NoPen);
+
+		// Compile polygons
+		for (int i = 0; i < segments; ++i)
+		{
+			QVector<QPointF> points;
+			points << innerverts2d[i]
+				<< innerverts2d[i + 1]
+				<< outerverts2d[i + 1]
+				<< outerverts2d[i];
+			painter.drawPolygon (QPolygonF (points));
+			lines << QLineF (innerverts2d[i], innerverts2d[i + 1]);
+			lines << QLineF (outerverts2d[i], outerverts2d[i + 1]);
+		}
+
+		// Add bordering edges for unclosed rings/discs
+		if (segments != divisions)
+		{
+			lines << QLineF (innerverts2d.first(), outerverts2d.first());
+			lines << QLineF (innerverts2d.last(), outerverts2d.last());
+		}
+	}
+	else
+	{
+		for (int i = 0; i < segments; ++i)
+			lines << QLineF (innerverts2d[i], innerverts2d[i + 1]);
+	}
+
+	// Draw a green blips at where the points are
+	for (QPointF const& point : innerverts2d + outerverts2d)
+		renderer()->drawBlip (painter, point);
+
+	// Draw edge lines
+	painter.setPen (renderer()->linePen());
+	painter.drawLines (lines);
+
+	// Draw the current radius in the middle of the circle.
+	QPoint origin = renderer()->coordconv3_2 (m_drawedVerts[0]);
+	QString label = QString::number (innerdistance);
+	painter.setPen (renderer()->textPen());
+	painter.drawText (origin.x() - (metrics.width (label) / 2), origin.y(), label);
+
+	if (m_drawedVerts.size() >= 2)
+	{
+		painter.drawText (origin.x() - (metrics.width (label) / 2),
+			origin.y() + metrics.height(), QString::number (outerdistance));
+	}
+}
+
+bool CircleMode::mouseReleased (MouseEventData const& data)
+{
+	if (Super::mouseReleased (data))
+		return true;
+
+	if (data.releasedButtons & Qt::LeftButton)
+	{
+		if (m_drawedVerts.size() < 3)
+			addDrawnVertex (renderer()->position3D());
+		else
+			buildCircle();
+
+		return true;
+	}
+
+	return false;
+}
+
+bool CircleMode::preAddVertex (const Vertex&)
+{
+	m_angleOffset = getAngleOffset();
+	return false;
+}