File indexing completed on 2024-07-14 07:17:22

0001 /*
0002     SPDX-FileCopyrightText: 2007 James B. Bowlin <bowlin@mindspring.com>
0003     SPDX-License-Identifier: GPL-2.0-or-later
0004 */
0005 
0006 #pragma once
0007 
0008 #include <QPointF>
0009 #include <QString>
0010 
0011 class LineList;
0012 class Projector;
0013 class SkyLabeler;
0014 
0015 /**
0016     * @class LabelListIndex
0017     * An abstract parent class to be inherited by Ecliptic and Equator.
0018     *
0019     * @author James B. Bowlin
0020     * @version 0.1
0021     */
0022 class LineListLabel
0023 {
0024   public:
0025     explicit LineListLabel(const QString &text);
0026 
0027     enum
0028     {
0029         TopCandidate,
0030         BotCandidate,
0031         LeftCandidate,
0032         RightCandidate
0033     };
0034 
0035     /** @short prepare the context for selecting label position candidates. */
0036     void reset();
0037 
0038     /**
0039      * @short draw the label if any.  Is currently called at the bottom of draw() but that call could
0040      * be removed and it could be called externally AFTER draw() has been called so draw() can set
0041      * up the label position candidates.
0042      */
0043     void draw();
0044 
0045     void updateLabelCandidates(qreal x, qreal y, LineList *lineList, int i);
0046 
0047   private:
0048     /**
0049      * @short This routine does two things at once.  It returns the QPointF
0050      * corresponding to pointList[i] and also computes the angle using
0051      * pointList[i] and pointList[i-1] therefore you MUST ensure that:
0052      *
0053      *     1 <= i < pointList.size().
0054      */
0055     QPointF angleAt(const Projector *proj, LineList *list, int i, double *angle);
0056 
0057     const QString m_text;
0058     SkyLabeler *m_skyLabeler { nullptr };
0059 
0060     // these two arrays track/contain 4 candidate points
0061     int m_labIndex[4] { 0, 0, 0, 0 };
0062     LineList *m_labList[4] { nullptr, nullptr, nullptr, nullptr };
0063 
0064     float m_marginLeft { 0 };
0065     float m_marginRight { 0 };
0066     float m_marginTop { 0 };
0067     float m_marginBot { 0 };
0068     float m_farLeft { 0 };
0069     float m_farRight { 0 };
0070     float m_farTop { 0 };
0071     float m_farBot { 0 };
0072 };