Tweak the ambience/crosfade layer to fade in regardless of another sample being there

Fix music not being looped sometimes
Prevent channel less than 0 from being passed
Set up a new music display element with an attached music name, it displays a scrolling text of the currently playing music
Fix music packet processing issues
Make SFX slider responsible for all music channels besides 0 (actual music)

scrolltext.cpp code recipe was taken from https://stackoverflow.com/questions/10651514/text-scrolling-marquee-in-qlabel - thanks to leemes for that one, I only adapted it for newer C++ version and tweaked some stuff.

1 files changed, 134 insertions, 0 deletions

diff --git a/src/scrolltext.cpp b/src/scrolltext.cpp
new file mode 100644
index 00000000..6cf075d2
--- /dev/null
+++ b/src/scrolltext.cpp
@@ -0,0 +1,134 @@
+#include "scrolltext.h"
+
+
+ScrollText::ScrollText(QWidget *parent) :
+    QWidget(parent), scrollPos(0)
+{
+    staticText.setTextFormat(Qt::PlainText);
+
+//    setFixedHeight(fontMetrics().height()*2); //The theme sets this
+    leftMargin = height() / 3;
+
+    setSeparator("   ---   ");
+
+    connect(&timer, SIGNAL(timeout()), this, SLOT(timer_timeout()));
+    timer.setInterval(50);
+}
+
+QString ScrollText::text() const
+{
+    return _text;
+}
+
+void ScrollText::setText(QString text)
+{
+    _text = text;
+    updateText();
+    update();
+}
+
+QString ScrollText::separator() const
+{
+    return _separator;
+}
+
+void ScrollText::setSeparator(QString separator)
+{
+    _separator = separator;
+    updateText();
+    update();
+}
+
+void ScrollText::updateText()
+{
+    timer.stop();
+
+    singleTextWidth = fontMetrics().horizontalAdvance(_text);
+    scrollEnabled = (singleTextWidth > width() - leftMargin*2);
+
+    if(scrollEnabled)
+    {
+        scrollPos = -64;
+        staticText.setText(_text + _separator);
+        timer.start();
+    }
+    else
+        staticText.setText(_text);
+
+    staticText.prepare(QTransform(), font());
+    wholeTextSize = QSize(fontMetrics().horizontalAdvance(staticText.text()), fontMetrics().height());
+}
+
+void ScrollText::paintEvent(QPaintEvent*)
+{
+    QPainter p(this);
+
+    if(scrollEnabled)
+    {
+        buffer.fill(qRgba(0, 0, 0, 0));
+        QPainter pb(&buffer);
+        pb.setPen(p.pen());
+        pb.setFont(p.font());
+
+        int x = qMin(-scrollPos, 0) + leftMargin;
+        while(x < width())
+        {
+            pb.drawStaticText(QPointF(x, (height() - wholeTextSize.height()) / 2), staticText);
+            x += wholeTextSize.width();
+        }
+
+        //Apply Alpha Channel
+        pb.setCompositionMode(QPainter::CompositionMode_DestinationIn);
+        pb.setClipRect(width() - 15, 0, 15, height());
+        pb.drawImage(0, 0, alphaChannel);
+        pb.setClipRect(0, 0, 15, height());
+        //initial situation: don't apply alpha channel in the left half of the image at all; apply it more and more until scrollPos gets positive
+        if(scrollPos < 0)
+            pb.setOpacity(static_cast<qreal>((qMax(-8, scrollPos) + 8) / 8.0));
+        pb.drawImage(0, 0, alphaChannel);
+
+        //pb.end();
+        p.drawImage(0, 0, buffer);
+    }
+    else
+    {
+        p.drawStaticText(QPointF(leftMargin, (height() - wholeTextSize.height()) / 2), staticText);
+    }
+}
+
+void ScrollText::resizeEvent(QResizeEvent*)
+{
+    //When the widget is resized, we need to update the alpha channel.
+
+    alphaChannel = QImage(size(), QImage::Format_ARGB32_Premultiplied);
+    buffer = QImage(size(), QImage::Format_ARGB32_Premultiplied);
+
+    //Create Alpha Channel:
+    if(width() > 64)
+    {
+        //create first scanline
+        QRgb* scanline1 = reinterpret_cast<QRgb*>(alphaChannel.scanLine(0));
+        for(int x = 1; x < 16; ++x)
+            scanline1[x - 1] = scanline1[width() - x] = qRgba(0, 0, 0, x << 4);
+        for(int x = 15; x < width() - 15; ++x)
+            scanline1[x] = qRgb(0, 0, 0);
+        //copy scanline to the other ones
+        for(int y = 1; y < height(); ++y)
+            memcpy(alphaChannel.scanLine(y), scanline1, static_cast<uint>(width() * 4));
+    }
+    else
+        alphaChannel.fill(qRgb(0, 0, 0));
+
+
+    //Update scrolling state
+    bool newScrollEnabled = (singleTextWidth > width() - leftMargin);
+    if(newScrollEnabled != scrollEnabled)
+        updateText();
+}
+
+void ScrollText::timer_timeout()
+{
+    scrollPos = (scrollPos + 2)
+                % wholeTextSize.width();
+    update();
+}