/**
* \todo TODO: do stretching histogram
*/
bool LinearStretchOperation::stretch(IRasterCoverage toStretch)
{
NumericStatistics& statistics = _inputRaster->statistics();
// TODO: separate histogram into own class (and move
// certain operations to it
SPNumericRange rng = _inputRaster->datadef().range<NumericRange>();
double valueRange = rng->distance();
PixelIterator iterInput(_inputRaster);
std::for_each(begin(_outputRaster), end(_outputRaster), [&](double& v) {
double vin = *iterInput;
if(vin >= _limits.first && vin <= _limits.second) {
v = statistics.stretchLinear(vin, valueRange);
}
++iterInput;
});
return true;
}
void RasterValueImage::setTextureData(ValueTexture *tex, const unsigned int offsetX, const unsigned int offsetY, unsigned int texSizeX, unsigned int texSizeY, unsigned int zoomFactor)
{
long imageWidth = _raster->size().xsize();
long imageHeight = _raster->size().ysize();
long sizeX = texSizeX; // the size of the input (pixeliterator)
long sizeY = texSizeY;
if (offsetX + sizeX > imageWidth)
sizeX = imageWidth - offsetX;
if (offsetY + sizeY > imageHeight)
sizeY = imageHeight - offsetY;
if (sizeX == 0 || sizeY == 0)
return;
const long xSizeOut = (long)ceil((double)sizeX / ((double)zoomFactor)); // the size until which the pixels vector will be filled (this is commonly the same as texSizeX, except the rightmost / bottommost textures, as raster-images seldom have as size of ^2)
texSizeX /= zoomFactor; // the actual size of the texture (commonly 256 or maxtexturesize, but smaller texture sizes may be allocated for the rightmost or bottommost textures)
texSizeY /= zoomFactor;
BoundingBox bb(Pixel(offsetX, offsetY), Pixel(offsetX + sizeX - 1, offsetY + sizeY - 1));
// the "pixels" array must be made 32-bit aligned (32-bit-alignment is required by QImage)
int xl = (quint32)texSizeX % 4 == 0 ? texSizeX : ((texSizeX / 4) + 1) * 4;
int rest = xl - texSizeX;
quint32 size = xl * texSizeY;
std::vector<quint8> * pixels = new std::vector<quint8> ();
pixels->resize(size);
PixelIterator pixIter(_raster, bb); // This iterator runs through bb. The corners of bb are "inclusive".
SPNumericRange numrange = _raster->datadef().range<NumericRange>();
if (!numrange->isValid())
_raster->statistics(NumericStatistics::pBASIC);
auto end = pixIter.end();
quint32 position = 0;
while(pixIter != end){
double value = *pixIter;
int index = isNumericalUndef2(value,_raster) ? 0 : 1 + (_colorTable.size() - 2) * (value - numrange->min()) / numrange->distance();
(*pixels)[position] = index; // int32 to quint8 conversion (do we want this?)
pixIter += zoomFactor;
if ( pixIter.ychanged()) {
position += (rest + texSizeX - xSizeOut);
if (zoomFactor > 1)
pixIter += sizeX * (zoomFactor - 1) - ((zoomFactor - (sizeX % zoomFactor)) % zoomFactor);
}
++position;
}
const uchar *datablock = (const uchar *)pixels->data();
QImage * image = new QImage(datablock, xl, texSizeY, QImage::Format_Indexed8);
image->setColorTable(_colorTable);
tex->setQImage(image, pixels); // carry over the image and the data-buffer to the texture object (see QImage documentation: the data-buffer must exist throughout the existence of the QImage)
}