QImage QwtPlotRasterItem::compose(
const QwtScaleMap &xMap, const QwtScaleMap &yMap,
const QRectF &imageArea, const QRectF &paintRect,
const QSize &imageSize, bool doCache) const
{
QImage image;
if ( imageArea.isEmpty() || paintRect.isEmpty() || imageSize.isEmpty() )
return image;
if ( doCache )
{
if ( !d_data->cache.image.isNull()
&& d_data->cache.area == imageArea
&& d_data->cache.size == paintRect.size() )
{
image = d_data->cache.image;
}
}
if ( image.isNull() )
{
double dx = 0.0;
if ( paintRect.toRect().width() > imageSize.width() )
dx = imageArea.width() / imageSize.width();
const QwtScaleMap xxMap =
imageMap(Qt::Horizontal, xMap, imageArea, imageSize, dx);
double dy = 0.0;
if ( paintRect.toRect().height() > imageSize.height() )
dy = imageArea.height() / imageSize.height();
const QwtScaleMap yyMap =
imageMap(Qt::Vertical, yMap, imageArea, imageSize, dy);
image = renderImage( xxMap, yyMap, imageArea, imageSize );
if ( doCache )
{
d_data->cache.area = imageArea;
d_data->cache.size = paintRect.size();
d_data->cache.image = image;
}
}
if ( d_data->alpha >= 0 && d_data->alpha < 255 )
image = toRgba( image, d_data->alpha );
return image;
}
/*!
\brief Draw the raster data
\param painter Painter
\param xMap X-Scale Map
\param yMap Y-Scale Map
\param canvasRect Contents rect of the plot canvas
*/
void QwtPlotRasterItem::draw(QPainter *painter,
const QwtScaleMap &xMap, const QwtScaleMap &yMap,
const QRect &canvasRect) const
{
if ( canvasRect.isEmpty() || d_data->alpha == 0 )
return;
QwtDoubleRect area = invTransform(xMap, yMap, canvasRect);
if ( boundingRect().isValid() )
area &= boundingRect();
const QRect paintRect = transform(xMap, yMap, area);
if ( !paintRect.isValid() )
return;
QImage image;
bool doCache = true;
if ( painter->device()->devType() == QInternal::Printer
|| painter->device()->devType() == QInternal::Picture )
{
doCache = false;
}
if ( !doCache || d_data->cache.policy == NoCache )
{
image = renderImage(xMap, yMap, area);
if ( d_data->alpha >= 0 && d_data->alpha < 255 )
image = toRgba(image, d_data->alpha);
}
else if ( d_data->cache.policy == PaintCache )
{
if ( d_data->cache.image.isNull() || d_data->cache.rect != area
|| d_data->cache.size != paintRect.size() )
{
d_data->cache.image = renderImage(xMap, yMap, area);
d_data->cache.rect = area;
d_data->cache.size = paintRect.size();
}
image = d_data->cache.image;
if ( d_data->alpha >= 0 && d_data->alpha < 255 )
image = toRgba(image, d_data->alpha);
}
else if ( d_data->cache.policy == ScreenCache )
{
const QSize screenSize =
QApplication::desktop()->screenGeometry().size();
if ( paintRect.width() > screenSize.width() ||
paintRect.height() > screenSize.height() )
{
image = renderImage(xMap, yMap, area);
}
else
{
if ( d_data->cache.image.isNull() || d_data->cache.rect != area )
{
QwtScaleMap cacheXMap = xMap;
cacheXMap.setPaintInterval( 0, screenSize.width());
QwtScaleMap cacheYMap = yMap;
cacheYMap.setPaintInterval(screenSize.height(), 0);
d_data->cache.image = renderImage(
cacheXMap, cacheYMap, area);
d_data->cache.rect = area;
d_data->cache.size = paintRect.size();
}
image = d_data->cache.image;
}
image = toRgba(image, d_data->alpha);
}
painter->drawImage(paintRect, image);
}
void DistanceGrid::convertToSdf(const u8 *pImageDataIn, u8 *pImageDataOut) {
fromRgba(pImageDataIn);
computeSdf(m_gridInside);
computeSdf(m_gridOutside);
toRgba(pImageDataOut);
}