src/editmodes/abstractEditMode.cpp

/*
 *  LDForge: LDraw parts authoring CAD
 *  Copyright (C) 2013 - 2018 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 <QMouseEvent>
#include <stdexcept>
#include "abstractEditMode.h"
#include "selectMode.h"
#include "drawMode.h"
#include "rectangleMode.h"
#include "circleMode.h"
#include "magicWandMode.h"
#include "linePathMode.h"
#include "curvemode.h"
#include "../mainwindow.h"
#include "../glRenderer.h"
#include "../miscallenous.h"

ConfigOption(bool DrawLineLengths = true)
ConfigOption(bool DrawAngles = false)

AbstractEditMode::AbstractEditMode(GLRenderer* renderer) :
	QObject(renderer),
	HierarchyElement(renderer),
	m_renderer(renderer) {}

AbstractEditMode::~AbstractEditMode() {}

AbstractEditMode* AbstractEditMode::createByType(GLRenderer* renderer, EditModeType type)
{
	switch(type)
	{
	case EditModeType::Select: return new SelectMode(renderer);
	case EditModeType::Draw: return new DrawMode(renderer);
	case EditModeType::Rectangle: return new RectangleMode(renderer);
	case EditModeType::Circle: return new CircleMode(renderer);
	case EditModeType::MagicWand: return new MagicWandMode(renderer);
	case EditModeType::LinePath: return new LinePathMode(renderer);
	case EditModeType::Curve: return new CurveMode(renderer);
	}

	throw std::logic_error("bad type given to AbstractEditMode::createByType");
}

GLRenderer* AbstractEditMode::renderer() const
{
	return m_renderer;
}

AbstractDrawMode::AbstractDrawMode(GLRenderer* renderer) :
	AbstractEditMode(renderer),
	m_polybrush(QBrush(QColor(64, 192, 0, 128)))
{
	renderer->setContextMenuPolicy(Qt::NoContextMenu); // We need the right mouse button for removing vertices
	renderer->setCursor(Qt::CrossCursor);
	m_window->currentDocument()->clearSelection();
	m_window->updateSelection();
	m_drawedVerts.clear();
}

AbstractSelectMode::AbstractSelectMode(GLRenderer* renderer) :
	AbstractEditMode(renderer)
{
	renderer->unsetCursor();
	renderer->setContextMenuPolicy(Qt::DefaultContextMenu);
}

// =============================================================================
//
void AbstractDrawMode::addDrawnVertex(Vertex const& pos)
{
	if (preAddVertex(pos))
		return;

	m_drawedVerts << pos;
}

bool AbstractDrawMode::mouseReleased(MouseEventData const& data)
{
	if (Super::mouseReleased(data))
		return true;

	if ((data.releasedButtons & Qt::MidButton) and(m_drawedVerts.size() < 4) and(not data.mouseMoved))
	{
		// Find the closest vertex to our cursor
		double			minimumDistance = 1024.0;
		const Vertex*	closest = nullptr;
		Vertex			cursorPosition = renderer()->convert2dTo3d(data.ev->pos(), false);
		QPoint			cursorPosition2D(data.ev->pos());
		const Axis		relZ = renderer()->getRelativeZ();
		QVector<Vertex>	vertices = renderer()->document()->inlineVertices();

		// Sort the vertices in order of distance to camera
		std::sort(vertices.begin(), vertices.end(), [&](const Vertex& a, const Vertex& b) -> bool
		{
			if (renderer()->getFixedCamera(renderer()->camera()).negatedDepth)
				return a[relZ] > b[relZ];

			return a[relZ] < b[relZ];
		});

		for (const Vertex& vrt : vertices)
		{
			// If the vertex in 2d space is very close to the cursor then we use it regardless of depth.
			QPoint vect2d = renderer()->convert3dTo2d(vrt) - cursorPosition2D;
			const double distance2DSquared = std::pow(vect2d.x(), 2) + std::pow(vect2d.y(), 2);
			if (distance2DSquared < 16.0 * 16.0)
			{
				closest = &vrt;
				break;
			}

			// Check if too far away from the cursor.
			if (distance2DSquared > 64.0 * 64.0)
				continue;

			// Not very close to the cursor. Compare using true distance,
			// including depth.
			const double distanceSquared = (vrt - cursorPosition).lengthSquared();

			if (distanceSquared < minimumDistance)
			{
				minimumDistance = distanceSquared;
				closest = &vrt;
			}
		}

		if (closest)
			addDrawnVertex(*closest);

		return true;
	}

	if ((data.releasedButtons & Qt::RightButton) and(not m_drawedVerts.isEmpty()))
	{
		// Remove the last vertex
		m_drawedVerts.removeLast();
		return true;
	}

	if (data.releasedButtons & Qt::LeftButton)
	{
		if (maxVertices() and m_drawedVerts.size() >= maxVertices())
		{
			endDraw();
			return true;
		}

		addDrawnVertex(getCursorVertex());
		return true;
	}

	return false;
}

void AbstractDrawMode::finishDraw(LDObjectList const& objs)
{
	int pos = m_window->suggestInsertPoint();

	if (objs.size() > 0)
	{
		for (LDObject* obj : objs)
		{
			renderer()->document()->insertObj(pos++, obj);
			renderer()->compileObject(obj);
		}

		m_window->refresh();
		m_window->endAction();
	}

	m_drawedVerts.clear();
}

void AbstractDrawMode::drawLength(QPainter &painter, const Vertex &v0, const Vertex &v1,
	const QPointF& v0p, const QPointF& v1p) const
{
	if (not config->drawLineLengths())
		return;

	const QString label = QString::number((v1 - v0).length());
	QPoint origin = QLineF(v0p, v1p).pointAt(0.5).toPoint();
	painter.drawText(origin, label);
}

void AbstractDrawMode::renderPolygon(QPainter& painter, const QVector<Vertex>& poly3d,
	bool withlengths, bool withangles) const
{
	QVector<QPoint> poly(poly3d.size());
	QFontMetrics metrics = QFontMetrics(QFont());

	// Convert to 2D
	for (int i = 0; i < poly3d.size(); ++i)
		poly[i] = renderer()->convert3dTo2d(poly3d[i]);

	// Draw the polygon-to-be
	painter.setBrush(m_polybrush);
	painter.drawPolygon(QPolygonF(poly));

	// Draw vertex blips
	for (int i = 0; i < poly3d.size(); ++i)
	{
		renderer()->drawBlip(painter, poly[i]);
		renderer()->drawBlipCoordinates(painter, poly3d[i], poly[i]);
	}

	// Draw line lenghts and angle info if appropriate
	if (poly3d.size() >= 2 and(withlengths or withangles))
	{
		painter.setPen(renderer()->textPen());

		for (int i = 0; i < poly3d.size(); ++i)
		{
			const int j = (i + 1) % poly3d.size();
			const int h = (i - 1 >= 0) ?(i - 1) :(poly3d.size() - 1);

			if (withlengths)
				drawLength(painter, poly3d[i], poly3d[j], poly[i], poly[j]);

			if (withangles and config->drawAngles())
			{
				QLineF l0(poly[h], poly[i]),
					l1(poly[i], poly[j]);

				double angle = 180 - l0.angleTo(l1);

				if (angle < 0)
					angle = 180 - l1.angleTo(l0);

				QString label = QString::number(angle) + QString::fromUtf8(QByteArray("\302\260"));
				QPoint pos = poly[i];
				pos.setY(pos.y() + metrics.height());

				painter.drawText(pos, label);
			}
		}
	}
}

bool AbstractDrawMode::keyReleased(QKeyEvent *ev)
{
	if (Super::keyReleased(ev))
		return true;

	if (not m_drawedVerts.isEmpty() and ev->key() == Qt::Key_Backspace)
	{
		m_drawedVerts.removeLast();
		return true;
	}

	return false;
}

template<typename T>
T intervalClamp(T a, T interval)
{
	T remainder = a % interval;

	if (remainder >= float(interval / 2))
		a += interval;

	a -= remainder;
	return a;
}

Vertex AbstractDrawMode::getCursorVertex() const
{
	Vertex result = renderer()->position3D();

	if (renderer()->keyboardModifiers() & Qt::ControlModifier
		and not m_drawedVerts.isEmpty())
	{
		Vertex const& v0 = m_drawedVerts.last();
		Vertex const& v1 = result;
		Axis relX, relY;

		renderer()->getRelativeAxes(relX, relY);
		QLineF ln(v0[relX], v0[relY], v1[relX], v1[relY]);
		ln.setAngle(intervalClamp<int>(ln.angle(), 45));
		result.setCoordinate(relX, Grid::Snap(ln.x2(), Grid::Coordinate));
		result.setCoordinate(relY, Grid::Snap(ln.y2(), Grid::Coordinate));
	}

	return result;
}