mapnik/plugins/input/gdal/gdal_featureset.cpp

483 lines
18 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2007 Artem Pavlenko
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*****************************************************************************/
//$Id$
#include "gdal_featureset.hpp"
#include <gdal_priv.h>
// boost
#include <boost/format.hpp>
using mapnik::query;
using mapnik::coord2d;
using mapnik::box2d;
using mapnik::Feature;
using mapnik::feature_ptr;
using mapnik::CoordTransform;
using mapnik::geometry_type;
using mapnik::datasource_exception;
gdal_featureset::gdal_featureset(GDALDataset & dataset, int band, gdal_query q,
mapnik::box2d<double> extent, double width, double height, int nbands,
double dx, double dy, double filter_factor)
: dataset_(dataset),
band_(band),
gquery_(q),
raster_extent_(extent),
raster_width_(width),
raster_height_(height),
dx_(dx),
dy_(dy),
nbands_(nbands),
filter_factor_(filter_factor),
first_(true)
{
}
gdal_featureset::~gdal_featureset()
{
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: closing dataset = " << &dataset_ << std::endl;
#endif
GDALClose(&dataset_);
}
feature_ptr gdal_featureset::next()
{
if (first_)
{
first_ = false;
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: featureset, dataset = " << &dataset_ << std::endl;
#endif
query *q = boost::get<query>(&gquery_);
if(q) {
return get_feature(*q);
} else {
coord2d *p = boost::get<coord2d>(&gquery_);
if(p) {
return get_feature_at_point(*p);
}
}
// should never reach here
}
return feature_ptr();
}
feature_ptr gdal_featureset::get_feature(mapnik::query const& q)
{
feature_ptr feature(new Feature(1));
GDALRasterBand * red = 0;
GDALRasterBand * green = 0;
GDALRasterBand * blue = 0;
GDALRasterBand * alpha = 0;
GDALRasterBand * grey = 0;
/*
double tr[6];
dataset_.GetGeoTransform(tr);
double dx = tr[1];
double dy = tr[5];
std::clog << "dx_: " << dx_ << " dx: " << dx << " dy_: " << dy_ << "dy: " << dy << "\n";
*/
CoordTransform t(raster_width_,raster_height_,raster_extent_,0,0);
box2d<double> intersect = raster_extent_.intersect(q.get_bbox());
box2d<double> box = t.forward(intersect);
//size of resized output pixel in source image domain
double margin_x = 1.0/(fabs(dx_)*boost::get<0>(q.resolution()));
double margin_y = 1.0/(fabs(dy_)*boost::get<1>(q.resolution()));
if (margin_x < 1)
margin_x = 1.0;
if (margin_y < 1)
margin_y = 1.0;
//select minimum raster containing whole box
int x_off = rint(box.minx() - margin_x);
int y_off = rint(box.miny() - margin_y);
int end_x = rint(box.maxx() + margin_x);
int end_y = rint(box.maxy() + margin_y);
//clip to available data
if (x_off < 0)
x_off = 0;
if (y_off < 0)
y_off = 0;
if (end_x > (int)raster_width_)
end_x = raster_width_;
if (end_y > (int)raster_height_)
end_y = raster_height_;
int width = end_x - x_off;
int height = end_y - y_off;
// don't process almost invisible data
if (box.width() < 0.5)
width = 0;
if (box.height() < 0.5)
height = 0;
//calculate actual box2d of returned raster
box2d<double> feature_raster_extent(x_off, y_off, x_off+width, y_off+height);
intersect = t.backward(feature_raster_extent);
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: Raster extent=" << raster_extent_ << std::endl;
std::clog << "GDAL Plugin: View extent=" << intersect << std::endl;
std::clog << "GDAL Plugin: Query resolution=" << boost::get<0>(q.resolution()) << "," << boost::get<1>(q.resolution()) << std::endl;
std::clog << boost::format("GDAL Plugin: StartX=%d StartY=%d Width=%d Height=%d") % x_off % y_off % width % height << std::endl;
#endif
if (width > 0 && height > 0)
{
double width_res = boost::get<0>(q.resolution());
double height_res = boost::get<1>(q.resolution());
int im_width = int(width_res * intersect.width() + 0.5);
int im_height = int(height_res * intersect.height() + 0.5);
// if layer-level filter_factor is set, apply it
if (filter_factor_)
{
im_width *= filter_factor_;
im_height *= filter_factor_;
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: applying layer filter_factor: " << filter_factor_ << "\n";
#endif
}
// otherwise respect symbolizer level factor applied to query, default of 1.0
else
{
double sym_downsample_factor = q.get_filter_factor();
im_width *= sym_downsample_factor;
im_height *= sym_downsample_factor;
}
// case where we need to avoid upsampling so that the
// image can be later scaled within raster_symbolizer
if (im_width >= width || im_height >= height)
{
im_width = width;
im_height = height;
}
if (im_width > 0 && im_height > 0)
{
mapnik::image_data_32 image(im_width, im_height);
image.set(0xffffffff);
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: Image Size=(" << im_width << "," << im_height << ")" << std::endl;
std::clog << "GDAL Plugin: Reading band " << band_ << std::endl;
#endif
typedef std::vector<int,int> pallete;
if (band_ > 0) // we are querying a single band
{
if (band_ > nbands_)
throw datasource_exception((boost::format("GDAL Plugin: '%d' is an invalid band, dataset only has '%d' bands\n") % band_ % nbands_).str());
float *imageData = (float*)image.getBytes();
GDALRasterBand * band = dataset_.GetRasterBand(band_);
int hasNoData;
double nodata = band->GetNoDataValue(&hasNoData);
band->RasterIO(GF_Read, x_off, y_off, width, height,
imageData, image.width(), image.height(),
GDT_Float32, 0, 0);
feature->set_raster(mapnik::raster_ptr(new mapnik::raster(intersect,image)));
if (hasNoData)
feature->props()["NODATA"]=nodata;
}
else // working with all bands
{
for (int i = 0; i < nbands_; ++i)
{
GDALRasterBand * band = dataset_.GetRasterBand(i+1);
#ifdef MAPNIK_DEBUG
get_overview_meta(band);
#endif
GDALColorInterp color_interp = band->GetColorInterpretation();
switch (color_interp)
{
case GCI_RedBand:
red = band;
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: Found red band" << std::endl;
#endif
break;
case GCI_GreenBand:
green = band;
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: Found green band" << std::endl;
#endif
break;
case GCI_BlueBand:
blue = band;
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: Found blue band" << std::endl;
#endif
break;
case GCI_AlphaBand:
alpha = band;
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: Found alpha band" << std::endl;
#endif
break;
case GCI_GrayIndex:
grey = band;
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: Found gray band" << std::endl;
#endif
break;
case GCI_PaletteIndex:
{
grey = band;
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: Found gray band, and colortable..." << std::endl;
#endif
GDALColorTable *color_table = band->GetColorTable();
if ( color_table)
{
int count = color_table->GetColorEntryCount();
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: Color Table count = " << count << std::endl;
#endif
for (int j = 0; j < count; j++)
{
const GDALColorEntry *ce = color_table->GetColorEntry (j);
if (! ce) continue;
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: Color entry RGB (" << ce->c1 << "," <<ce->c2 << "," << ce->c3 << ")" << std::endl;
#endif
}
}
break;
}
case GCI_Undefined:
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: Found undefined band (assumming gray band)" << std::endl;
#endif
grey = band;
break;
default:
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: band type unknown!" << std::endl;
#endif
break;
}
}
if (red && green && blue)
{
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: processing rgb bands..." << std::endl;
#endif
int hasNoData;
float nodata = red->GetNoDataValue(&hasNoData);
GDALColorTable *color_table = red->GetColorTable();
if (!alpha && hasNoData && !color_table)
{
// first read the data in and create an alpha channel from the nodata values
float *imageData = (float*)image.getBytes();
red->RasterIO(GF_Read, x_off, y_off, width, height,
imageData, image.width(), image.height(),
GDT_Float32, 0, 0);
int len = image.width() * image.height();
for (int i=0; i<len; ++i)
{
if (nodata == imageData[i])
*reinterpret_cast<unsigned *> (&imageData[i]) = 0;
else
*reinterpret_cast<unsigned *> (&imageData[i]) = 0xFFFFFFFF;
}
}
red->RasterIO(GF_Read,x_off,y_off,width,height,image.getBytes() + 0,
image.width(),image.height(),GDT_Byte,4,4*image.width());
green->RasterIO(GF_Read,x_off,y_off,width,height,image.getBytes() + 1,
image.width(),image.height(),GDT_Byte,4,4*image.width());
blue->RasterIO(GF_Read,x_off,y_off,width,height,image.getBytes() + 2,
image.width(),image.height(),GDT_Byte,4,4*image.width());
}
else if (grey)
{
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: processing gray band..." << std::endl;
#endif
int hasNoData;
float nodata = grey->GetNoDataValue(&hasNoData);
GDALColorTable *color_table = grey->GetColorTable();
if (hasNoData && !color_table)
{
#ifdef MAPNIK_DEBUG
std::clog << "\tno data value for layer: " << nodata << std::endl;
#endif
// first read the data in and create an alpha channel from the nodata values
float *imageData = (float*)image.getBytes();
grey->RasterIO(GF_Read, x_off, y_off, width, height,
imageData, image.width(), image.height(),
GDT_Float32, 0, 0);
int len = image.width() * image.height();
for (int i=0; i<len; ++i)
{
if (nodata == imageData[i])
*reinterpret_cast<unsigned *> (&imageData[i]) = 0;
else
*reinterpret_cast<unsigned *> (&imageData[i]) = 0xFFFFFFFF;
}
}
grey->RasterIO(GF_Read,x_off,y_off,width,height,image.getBytes() + 0,
image.width(),image.height(),GDT_Byte, 4, 4 * image.width());
grey->RasterIO(GF_Read,x_off,y_off,width,height,image.getBytes() + 1,
image.width(),image.height(),GDT_Byte, 4, 4 * image.width());
grey->RasterIO(GF_Read,x_off,y_off,width,height,image.getBytes() + 2,
image.width(),image.height(),GDT_Byte, 4, 4 * image.width());
if (color_table)
{
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: Loading colour table..." << std::endl;
#endif
for (unsigned y = 0; y < image.height(); ++y)
{
unsigned int* row = image.getRow(y);
for (unsigned x = 0; x < image.width(); ++x)
{
unsigned value = row[x] & 0xff;
const GDALColorEntry *ce = color_table->GetColorEntry ( value );
if (ce ){
// TODO - big endian support
row[x] = (ce->c4 << 24)| (ce->c3 << 16) | (ce->c2 << 8) | (ce->c1) ;
}
}
}
}
}
if (alpha)
{
#ifdef MAPNIK_DEBUG
std::clog << "GDAL Plugin: processing alpha band..." << std::endl;
#endif
alpha->RasterIO(GF_Read,x_off,y_off,width,height,image.getBytes() + 3,
image.width(),image.height(),GDT_Byte,4,4*image.width());
}
feature->set_raster(mapnik::raster_ptr(new mapnik::raster(intersect,image)));
}
return feature;
}
}
return feature_ptr();
}
feature_ptr gdal_featureset::get_feature_at_point(mapnik::coord2d const& pt)
{
if (band_ > 0)
{
unsigned raster_xsize = dataset_.GetRasterXSize();
unsigned raster_ysize = dataset_.GetRasterYSize();
double gt[6];
dataset_.GetGeoTransform(gt);
double det = gt[1]*gt[5] - gt[2]*gt[4];
// subtract half a pixel width & height because gdal coord reference
// is the top-left corner of a pixel, not the center.
double X = pt.x - gt[0] - gt[1]/2;
double Y = pt.y - gt[3] - gt[5]/2;
double det1 = gt[1]*Y + gt[4]*X;
double det2 = gt[2]*Y + gt[5]*X;
unsigned x = det2/det, y = det1/det;
if (x < raster_xsize && y < raster_ysize)
{
#ifdef MAPNIK_DEBUG
std::clog << boost::format("GDAL Plugin: pt.x=%f pt.y=%f") % pt.x % pt.y << std::endl;
std::clog << boost::format("GDAL Plugin: x=%f y=%f") % x % y << std::endl;
#endif
GDALRasterBand * band = dataset_.GetRasterBand(band_);
int hasNoData;
double nodata = band->GetNoDataValue(&hasNoData);
double value;
band->RasterIO(GF_Read, x, y, 1, 1, &value, 1, 1, GDT_Float64, 0, 0);
if (! hasNoData || value != nodata)
{
// construct feature
feature_ptr feature(new Feature(1));
geometry_type * point = new geometry_type(mapnik::Point);
point->move_to(pt.x, pt.y);
feature->add_geometry(point);
(*feature)["value"] = value;
return feature;
}
}
}
return feature_ptr();
}
#ifdef MAPNIK_DEBUG
void gdal_featureset::get_overview_meta(GDALRasterBand * band)
{
int band_overviews = band->GetOverviewCount();
if (band_overviews > 0)
{
std::clog << "GDAL Plugin: "<< band_overviews << " overviews found!" << std::endl;
for (int b = 0; b < band_overviews; b++)
{
GDALRasterBand * overview = band->GetOverview (b);
std::clog << boost::format("GDAL Plugin: Overview=%d Width=%d Height=%d")
% b % overview->GetXSize() % overview->GetYSize() << std::endl;
}
}
else
{
std::clog << "GDAL Plugin: No overviews found!" << std::endl;
}
int bsx,bsy;
double scale;
band->GetBlockSize(&bsx,&bsy);
scale = band->GetScale();
std::clog << boost::format("GDAL Plugin: Block=%dx%d Scale=%f Type=%s Color=%s") % bsx % bsy % scale
% GDALGetDataTypeName(band->GetRasterDataType())
% GDALGetColorInterpretationName(band->GetColorInterpretation()) << std::endl;
}
#endif