Render artefacts on top right of Hex Table

[Andrea]

I have just updated after a long time and realised there are some artefacts on the top right of the Hex panel.
That area is sometimes white sometimes with hex values.

I am still trying to figure out if there is anything specific that triggers it.

[Andrea]

It has something to do with another QT window below the Hex Viewer.
But it was not happening before at 2ad23ee.
Is the hex window fully repainted every time?

[Andrea]

Bisection points to this: d26bd46.

[Andrea]

It looks to be an off-by-one (or similar) around this logic

https://github.com/Dax89/QHexView/blob/master/qhexview.cpp#L249

It is not redrawing all necessary lines.

[Andrea]

    const int lineHeight = m_renderer->lineHeight();
    const qint64 first = firstvisible + std::max(0, (r.top() / lineHeight) - 1);
    const qint64 last = firstvisible + (r.bottom() / lineHeight) + 1;
    int count = static_cast<int>((last - first) + 1);

This fixes it, but I cannot yet pinpoint to the exact error.

[Andrea]

Here it is

    const quint64 firstVisible = this->firstVisibleLine();
    const int lineHeight = m_renderer->lineHeight();
    const int headerCount = m_renderer->headerLineCount();

    const int first = std::max(0, (r.top() / lineHeight) - headerCount);  // because all lines are moved down by header
    const int last = (r.bottom()  + lineHeight - 1) / lineHeight;  // round up for fractional line
    const int count = (last - first) + 1;

    m_renderer->render(&painter, firstVisible + first, count, firstVisible);

Will provide a PR.

[Andrea]

#42