qgraphicsanchorlayout_p.cpp File Reference

#include <QtGui/qwidget.h>
#include <QtGui/qapplication.h>
#include <QtCore/qlinkedlist.h>
#include <QtCore/qstack.h>
#include <QtCore/qfile.h>
#include "qgraphicsanchorlayout_p.h"

Go to the source code of this file.

Enumerations
enum	slackType { Grower = -1, Shrinker = 1 }

Functions
static void	applySizePolicy (QSizePolicy::Policy policy, qreal minSizeHint, qreal prefSizeHint, qreal maxSizeHint, qreal *minSize, qreal *prefSize, qreal *maxSize)
static qreal	checkAdd (qreal a, qreal b)
static AnchorData *	createSequence (Graph< AnchorVertex, AnchorData > *graph, AnchorVertex *before, const QVector< AnchorVertex *> &vertices, AnchorVertex *after)
	Takes the sequence of vertices described by (before, vertices, after) and removes all anchors connected to the vertices in vertices, returning one simplified anchor between before and after. More...
static QPair< QSimplexVariable *, QSimplexConstraint * >	createSlack (QSimplexConstraint *sizeConstraint, qreal interval, slackType type)
static QPair< QGraphicsAnchorLayoutPrivate::Interval, qreal >	getFactor (qreal value, qreal min, qreal minPref, qreal pref, qreal maxPref, qreal max)
QList< AnchorData * >	getVariables (QList< QSimplexConstraint *> constraints)
static qreal	interpolate (const QPair< QGraphicsAnchorLayoutPrivate::Interval, qreal > &factor, qreal min, qreal minPref, qreal pref, qreal maxPref, qreal max)
static AnchorVertex *	replaceVertex_helper (AnchorData *data, AnchorVertex *oldV, AnchorVertex *newV)
static void	shiftConstraints (const QList< QSimplexConstraint *> &constraints, qreal amount)
	Shift all the constraints by a certain amount. More...

Variables
const qreal	g_offset = (sizeof(qreal) == sizeof(double)) ? QWIDGETSIZE_MAX : QWIDGETSIZE_MAX / 32

Enumeration Type Documentation

slackType

enum slackType

Enumerator
Grower
Shrinker

Definition at line 2916 of file qgraphicsanchorlayout_p.cpp.

{ Grower = -1, Shrinker = 1 };

Function Documentation

applySizePolicy()

static void applySizePolicy ( QSizePolicy::Policy  policy, qreal  minSizeHint, qreal  prefSizeHint, qreal  maxSizeHint, qreal *  minSize, qreal *  prefSize, qreal *  maxSize  )

static

Definition at line 131 of file qgraphicsanchorlayout_p.cpp.

Referenced by AnchorData::refreshSizeHints().

{
    // minSize, prefSize and maxSize are initialized
    // with item's preferred Size: this is QSizePolicy::Fixed.
    //
    // Then we check each flag to find the resultant QSizePolicy,
    // according to the following table:
    //
    //      constant               value
    // QSizePolicy::Fixed            0
    // QSizePolicy::Minimum       GrowFlag
    // QSizePolicy::Maximum       ShrinkFlag
    // QSizePolicy::Preferred     GrowFlag | ShrinkFlag
    // QSizePolicy::Ignored       GrowFlag | ShrinkFlag | IgnoreFlag

    if (policy & QSizePolicy::ShrinkFlag)
        *minSize = minSizeHint;
    else
        *minSize = prefSizeHint;

    if (policy & QSizePolicy::GrowFlag)
        *maxSize = maxSizeHint;
    else
        *maxSize = prefSizeHint;

    // Note that these two initializations are affected by the previous flags
    if (policy & QSizePolicy::IgnoreFlag)
        *prefSize = *minSize;
    else
        *prefSize = prefSizeHint;
}

checkAdd()

static qreal checkAdd ( qreal  a, qreal  b  )

inlinestatic

Warning

This function is not part of the public interface.

helper function in order to avoid overflowing anchor sizes the returned size will never be larger than FLT_MAX

Definition at line 670 of file qgraphicsanchorlayout_p.cpp.

{
    if (FLT_MAX - b  < a)
        return FLT_MAX;
    return a + b;
}

createSequence()

static AnchorData* createSequence ( Graph< AnchorVertex, AnchorData > *  graph, AnchorVertex *  before, const QVector< AnchorVertex *> &  vertices, AnchorVertex *  after  )

static

Takes the sequence of vertices described by (before, vertices, after) and removes all anchors connected to the vertices in vertices, returning one simplified anchor between before and after.

Warning

This function is not part of the public interface.

Note that this function doesn't add the created anchor to the graph. This should be done by the caller.

Definition at line 766 of file qgraphicsanchorlayout_p.cpp.

Referenced by QGraphicsAnchorLayoutPrivate::simplifyGraphIteration().

{
#if defined(QT_DEBUG) && 0
    QString strVertices;
    for (int i = 0; i < vertices.count(); ++i) {
        strVertices += QString::fromAscii("%1 - ").arg(vertices.at(i)->toString());
    }
    QString strPath = QString::fromAscii("%1 - %2%3").arg(before->toString(), strVertices, after->toString());
    qDebug("simplifying [%s] to [%s - %s]", qPrintable(strPath), qPrintable(before->toString()), qPrintable(after->toString()));
#endif

    AnchorVertex *prev = before;
    QVector<AnchorData *> edges;

    // Take from the graph, the edges that will be simplificated
    for (int i = 0; i < vertices.count(); ++i) {
        AnchorVertex *next = vertices.at(i);
        AnchorData *ad = graph->takeEdge(prev, next);
        Q_ASSERT(ad);
        edges.append(ad);
        prev = next;
    }

    // Take the last edge (not covered in the loop above)
    AnchorData *ad = graph->takeEdge(vertices.last(), after);
    Q_ASSERT(ad);
    edges.append(ad);

    // Create sequence
    SequentialAnchorData *sequence = new SequentialAnchorData(vertices, edges);
    sequence->from = before;
    sequence->to = after;

    sequence->calculateSizeHints();

    return sequence;
}

createSlack()

static QPair<QSimplexVariable *, QSimplexConstraint *> createSlack ( QSimplexConstraint *  sizeConstraint, qreal  interval, slackType  type  )

static

Definition at line 2917 of file qgraphicsanchorlayout_p.cpp.

Referenced by QGraphicsAnchorLayoutPrivate::solvePreferred().

{
    QSimplexVariable *slack = new QSimplexVariable;
    sizeConstraint->variables.insert(slack, type);

    QSimplexConstraint *limit = new QSimplexConstraint;
    limit->variables.insert(slack, 1.0);
    limit->ratio = QSimplexConstraint::LessOrEqual;
    limit->constant = interval;

    return qMakePair(slack, limit);
}

getFactor()

static QPair<QGraphicsAnchorLayoutPrivate::Interval, qreal> getFactor ( qreal  value, qreal  min, qreal  minPref, qreal  pref, qreal  maxPref, qreal  max  )

static

Warning

This function is not part of the public interface. returns the factor in the interval [-1, 1]. -1 is at Minimum 0 is at Preferred 1 is at Maximum

Definition at line 415 of file qgraphicsanchorlayout_p.cpp.

Referenced by QGraphicsAnchorLayoutPrivate::setupEdgesInterpolation(), and SequentialAnchorData::updateChildrenSizes().

{
    QGraphicsAnchorLayoutPrivate::Interval interval;
    qreal lower;
    qreal upper;

    if (value < minPref) {
        interval = QGraphicsAnchorLayoutPrivate::MinimumToMinPreferred;
        lower = min;
        upper = minPref;
    } else if (value < pref) {
        interval = QGraphicsAnchorLayoutPrivate::MinPreferredToPreferred;
        lower = minPref;
        upper = pref;
    } else if (value < maxPref) {
        interval = QGraphicsAnchorLayoutPrivate::PreferredToMaxPreferred;
        lower = pref;
        upper = maxPref;
    } else {
        interval = QGraphicsAnchorLayoutPrivate::MaxPreferredToMaximum;
        lower = maxPref;
        upper = max;
    }

    qreal progress;
    if (upper == lower) {
        progress = 0;
    } else {
        progress = (value - lower) / (upper - lower);
    }

    return qMakePair(interval, progress);
}

getVariables()

QList<AnchorData *> getVariables

(

QList< QSimplexConstraint *>

constraints

)

Definition at line 2098 of file qgraphicsanchorlayout_p.cpp.

Referenced by QGraphicsAnchorLayoutPrivate::calculateGraphs(), and QGraphicsAnchorLayoutPrivate::solveMinMax().

{
    QSet<AnchorData *> variableSet;
    for (int i = 0; i < constraints.count(); ++i) {
        const QSimplexConstraint *c = constraints.at(i);
        foreach (QSimplexVariable *var, c->variables.keys()) {
            variableSet += static_cast<AnchorData *>(var);
        }
    }
    return variableSet.toList();
}

interpolate()

static qreal interpolate ( const QPair< QGraphicsAnchorLayoutPrivate::Interval, qreal > &  factor, qreal  min, qreal  minPref, qreal  pref, qreal  maxPref, qreal  max  )

static

Definition at line 451 of file qgraphicsanchorlayout_p.cpp.

Referenced by QGraphicsAnchorLayoutPrivate::interpolateEdge(), and SequentialAnchorData::updateChildrenSizes().

{
    qreal lower = 0;
    qreal upper = 0;

    switch (factor.first) {
    case QGraphicsAnchorLayoutPrivate::MinimumToMinPreferred:
        lower = min;
        upper = minPref;
        break;
    case QGraphicsAnchorLayoutPrivate::MinPreferredToPreferred:
        lower = minPref;
        upper = pref;
        break;
    case QGraphicsAnchorLayoutPrivate::PreferredToMaxPreferred:
        lower = pref;
        upper = maxPref;
        break;
    case QGraphicsAnchorLayoutPrivate::MaxPreferredToMaximum:
        lower = maxPref;
        upper = max;
        break;
    }

    return lower + factor.second * (upper - lower);
}

replaceVertex_helper()

static AnchorVertex* replaceVertex_helper ( AnchorData *  data, AnchorVertex *  oldV, AnchorVertex *  newV  )

static

Definition at line 891 of file qgraphicsanchorlayout_p.cpp.

Referenced by QGraphicsAnchorLayoutPrivate::replaceVertex(), and QGraphicsAnchorLayoutPrivate::restoreVertices().

{
    AnchorVertex *other;
    if (data->from == oldV) {
        data->from = newV;
        other = data->to;
    } else {
        data->to = newV;
        other = data->from;
    }
    return other;
}

shiftConstraints()

static void shiftConstraints ( const QList< QSimplexConstraint *> &  constraints, qreal  amount  )

static

Shift all the constraints by a certain amount.

Warning

This function is not part of the public interface.

This allows us to deal with negative values in the linear program if they are bounded by a certain limit. Functions should be careful to call it again with a negative amount, to shift the constraints back.

Definition at line 2228 of file qgraphicsanchorlayout_p.cpp.

Referenced by QGraphicsAnchorLayoutPrivate::calculateNonTrunk(), and QGraphicsAnchorLayoutPrivate::calculateTrunk().

{
    for (int i = 0; i < constraints.count(); ++i) {
        QSimplexConstraint *c = constraints.at(i);
        qreal multiplier = 0;
        foreach (qreal v, c->variables.values()) {
            multiplier += v;
        }
        c->constant += multiplier * amount;
    }
}

Variable Documentation

g_offset

const qreal g_offset = (sizeof(qreal) == sizeof(double)) ? QWIDGETSIZE_MAX : QWIDGETSIZE_MAX / 32

Definition at line 62 of file qgraphicsanchorlayout_p.cpp.

Referenced by QGraphicsAnchorLayoutPrivate::calculateNonTrunk(), QGraphicsAnchorLayoutPrivate::calculateTrunk(), QGraphicsAnchorLayoutPrivate::constraintsFromSizeHints(), QGraphicsAnchorLayoutPrivate::solveMinMax(), and QGraphicsAnchorLayoutPrivate::solvePreferred().