Text rendering algorithm improvements

This commit is contained in:
Martin Tůma 2018-11-03 19:16:08 +01:00
parent f0a8b5c05e
commit a4089f9a29
5 changed files with 60 additions and 30 deletions

View File

@ -22,9 +22,9 @@ private:
class FunctionC {
public:
FunctionC(const QColor &deflt = QColor())
FunctionC(const QColor &deflt = QColor(Qt::black))
: _default(deflt), _base(1.0) {}
FunctionC(const QJsonObject &json, const QColor &dflt = QColor());
FunctionC(const QJsonObject &json, const QColor &dflt = QColor(Qt::black));
QColor value(qreal x) const;

View File

@ -141,11 +141,14 @@ Style::Layer::Paint::Paint(const QJsonObject &json)
_fillOpacity = FunctionF(json["fill-opacity"].toDouble());
else if (json.contains("fill-opacity") && json["fill-opacity"].isObject())
_fillOpacity = FunctionF(json["fill-opacity"].toObject());
if (json.contains("fill-color") && json["fill-color"].isString())
if (json.contains("fill-color") && json["fill-color"].isString()) {
_fillColor = FunctionC(Color::fromJsonString(
json["fill-color"].toString()));
if (json.contains("fill-color") && json["fill-color"].isObject())
_fillOutlineColor = _fillColor;
} else if (json.contains("fill-color") && json["fill-color"].isObject()) {
_fillColor = FunctionC(json["fill-color"].toObject());
_fillOutlineColor = _fillColor;
}
if (json.contains("fill-outline-color")
&& json["fill-outline-color"].isString())
_fillOutlineColor = FunctionC(Color::fromJsonString(
@ -155,6 +158,11 @@ Style::Layer::Paint::Paint(const QJsonObject &json)
_fillOutlineColor = FunctionC(json["fill-outline-color"].toObject());
if (json.contains("fill-antialias") && json["fill-antialias"].isBool())
_fillAntialias = json["fill-antialias"].toBool();
if (json.contains("fill-pattern")) {
_fillColor = FunctionC(QColor());
_fillOutlineColor = FunctionC(QColor());
}
if (json.contains("line-color") && json["line-color"].isString())
_lineColor = FunctionC(Color::fromJsonString(json["line-color"]
@ -208,11 +216,6 @@ QPen Style::Layer::Paint::pen(Type type, int zoom) const
color = _fillOutlineColor.value(zoom);
if (color.isValid())
pen = QPen(color);
else {
color = _fillColor.value(zoom);
if (color.isValid())
pen = QPen(color);
}
break;
case Symbol:
color = _textColor.value(zoom);
@ -267,8 +270,8 @@ bool Style::Layer::Paint::antialias(Layer::Type type) const
}
Style::Layer::Layout::Layout(const QJsonObject &json)
: _textSize(16), _textMaxWidth(10), _textMaxAngle(45), _lineCap(Qt::FlatCap),
_lineJoin(Qt::MiterJoin), _capitalize(false)
: _textSize(16), _textMaxWidth(10), _textMaxAngle(45), _symbolSpacing(250),
_lineCap(Qt::FlatCap), _lineJoin(Qt::MiterJoin), _capitalize(false)
{
if (!(json.contains("text-field") && json["text-field"].isString()))
return;
@ -296,6 +299,11 @@ Style::Layer::Layout::Layout(const QJsonObject &json)
else if (json.contains("text-max-angle") && json["text-max-angle"].isDouble())
_textMaxWidth = json["text-max-angle"].toDouble();
if (json.contains("symbol-spacing") && json["symbol-spacing"].isObject())
_symbolSpacing = json["symbol-spacing"].toObject();
else if (json.contains("symbol-spacing") && json["symbol-spacing"].isDouble())
_symbolSpacing = json["symbol-spacing"].toDouble();
if (json.contains("text-transform") && json["text-transform"].isString())
_capitalize = json["text-transform"].toString() == "uppercase";
@ -409,7 +417,7 @@ void Style::Layer::drawSymbol(int zoom, const QPainterPath &path,
_layout.maxTextWidth(zoom));
else
tile.text().addLabel(text.trimmed(), path, font, pen,
_layout.maxTextAngle(zoom));
_layout.maxTextAngle(zoom), _layout.symbolSpacing(zoom));
}
bool Style::load(const QString &fileName)

View File

@ -79,13 +79,17 @@ private:
class Layout {
public:
Layout() : _textSize(16), _textMaxWidth(10), _textMaxAngle(45),
_lineCap(Qt::FlatCap), _lineJoin(Qt::MiterJoin),
_capitalize(false) {}
_symbolSpacing(250), _lineCap(Qt::FlatCap),
_lineJoin(Qt::MiterJoin), _capitalize(false) {}
Layout(const QJsonObject &json);
bool capitalize() const {return _capitalize;}
qreal maxTextWidth(int zoom) const {return _textMaxWidth.value(zoom);}
qreal maxTextAngle(int zoom) const {return _textMaxAngle.value(zoom);}
qreal maxTextWidth(int zoom) const
{return _textMaxWidth.value(zoom);}
qreal maxTextAngle(int zoom) const
{return _textMaxAngle.value(zoom);}
qreal symbolSpacing(int zoom) const
{return _symbolSpacing.value(zoom);}
const QString &field() const {return _textField;}
const QStringList &keys() const {return _keys;}
QFont font(int zoom) const;
@ -98,6 +102,7 @@ private:
FunctionF _textSize;
FunctionF _textMaxWidth;
FunctionF _textMaxAngle;
FunctionF _symbolSpacing;
Qt::PenCapStyle _lineCap;
Qt::PenJoinStyle _lineJoin;
bool _capitalize;

View File

@ -6,43 +6,60 @@
#include "textpathitem.h"
static QPainterPath subpath(const QPainterPath &path, int start, int end)
static QPainterPath subpath(const QPainterPath &path, int start, int end,
qreal cut)
{
QPainterPath p(path.elementAt(start));
for (int i = start + 1; i <= end; i++)
for (int i = start + 1; i < end; i++)
p.lineTo(path.elementAt(i));
QLineF l(path.elementAt(end - 1), path.elementAt(end));
l.setLength(l.length() - cut);
p.lineTo(l.p2());
return p;
}
static QList<QPainterPath> segments(const QPainterPath &path, qreal pathLimit,
qreal maxAngle, qreal charWidth, const QRectF &tileRect)
static QList<QPainterPath> segments(const QPainterPath &path, qreal textLength,
qreal maxAngle, qreal charWidth, int symbolSpacing, const QRectF &tileRect)
{
QList<QPainterPath> list;
int start = 0;
qreal length = 0;
qreal angle = -1;
qreal dist = symbolSpacing;
for (int i = 1; i < path.elementCount(); i++) {
QLineF l(path.elementAt(i-1), path.elementAt(i));
qreal a = l.angle();
qreal sl = l.length();
if (dist < symbolSpacing) {
dist += sl;
start++;
continue;
}
qreal a = l.angle();
if (angle < 0)
angle = a;
if (!tileRect.contains(path.elementAt(i))
|| sl < charWidth || qAbs(angle - a) > maxAngle
|| length > pathLimit) {
if (length > pathLimit)
list.append(subpath(path, start, i - 1));
|| length > textLength) {
if (length > textLength) {
list.append(subpath(path, start, i - 1, length - textLength - 1));
dist = 0;
}
start = i;
length = 0;
} else
length += sl;
dist += sl;
angle = a;
}
if (length > pathLimit)
list.append(subpath(path, start, path.elementCount() - 1));
return list;
}
@ -76,7 +93,7 @@ void Text::addLabel(const QString &text, const QPointF &pos, const QFont &font,
}
void Text::addLabel(const QString &text, const QPainterPath &path,
const QFont &font, const QPen &pen, qreal maxAngle)
const QFont &font, const QPen &pen, qreal maxAngle, qreal symbolSpacing)
{
if (path.elementCount() < 2 || !path.elementAt(0).isMoveTo())
return;
@ -90,7 +107,7 @@ void Text::addLabel(const QString &text, const QPainterPath &path,
return;
QList<QPainterPath> list(segments(path, textWidth, maxAngle,
fm.averageCharWidth(), sceneRect()));
fm.averageCharWidth(), symbolSpacing, sceneRect()));
for (int i = 0; i < list.size(); i++) {
const QPainterPath &segment = list.at(i);
TextPathItem *pi = new TextPathItem(text, reverse(segment)

View File

@ -12,7 +12,7 @@ public:
void addLabel(const QString &text, const QPointF &pos, const QFont &font,
const QPen &pen, qreal maxTextWidth);
void addLabel(const QString &text, const QPainterPath &path,
const QFont &font, const QPen &pen, qreal maxAngle);
const QFont &font, const QPen &pen, qreal maxAngle, qreal symbolSpacing);
};
#endif // TEXT_H