C++ query::resolution方法代码示例

feature_ptr rasterlite_featureset::get_feature(mapnik::query const& q)
{
    MAPNIK_LOG_DEBUG(rasterlite) << "rasterlite_featureset: Running get_feature";

    feature_ptr feature(feature_factory::create(ctx_,1));

    double x0, y0, x1, y1;
    rasterliteGetExtent (dataset_, &x0, &y0, &x1, &y1);

    box2d<double> raster_extent(x0, y0, x1, y1);
    box2d<double> intersect = raster_extent.intersect(q.get_bbox());

    const int width = static_cast<int>(std::get<0>(q.resolution()) * intersect.width() + 0.5);
    const int height = static_cast<int>(std::get<0>(q.resolution()) * intersect.height() + 0.5);

    const double pixel_size = (intersect.width() >= intersect.height()) ?
        (intersect.width() / (double) width) : (intersect.height() / (double) height);

    MAPNIK_LOG_DEBUG(rasterlite) << "rasterlite_featureset: Raster extent=" << raster_extent;
    MAPNIK_LOG_DEBUG(rasterlite) << "rasterlite_featureset: View extent=" << q.get_bbox();
    MAPNIK_LOG_DEBUG(rasterlite) << "rasterlite_featureset: Intersect extent=" << intersect;
    MAPNIK_LOG_DEBUG(rasterlite) << "rasterlite_featureset: Query resolution=" << std::get<0>(q.resolution())  << "," << std::get<1>(q.resolution());
    MAPNIK_LOG_DEBUG(rasterlite) << "rasterlite_featureset: Size=" << width << " " << height;
    MAPNIK_LOG_DEBUG(rasterlite) << "rasterlite_featureset: Pixel Size=" << pixel_size;

    if (width > 0 && height > 0)
    {
        int size = 0;
        void* raster = 0;

        if (rasterliteGetRawImageByRect(dataset_,
                                        intersect.minx(),
                                        intersect.miny(),
                                        intersect.maxx(),
                                        intersect.maxy(),
                                        pixel_size,
                                        width,
                                        height,
                                        GAIA_RGBA_ARRAY,
                                        &raster,
                                        &size) == RASTERLITE_OK)
        {
            if (size > 0)
            {
                mapnik::image_rgba8 image(width,height);
                unsigned char* raster_data = static_cast<unsigned char*>(raster);
                std::memcpy(image.bytes(), raster_data, size);
                feature->set_raster(std::make_shared<mapnik::raster>(intersect, std::move(image), 1.0));
                MAPNIK_LOG_DEBUG(rasterlite) << "rasterlite_featureset: Done";
            }
            else
            {
                MAPNIK_LOG_ERROR(rasterlite) << "Rasterlite Plugin: Error " << rasterliteGetLastError (dataset_);
            }
        }

        return feature;
    }
    return feature_ptr();
}

mapnik::featureset_ptr rasterizer_datasource::features(const mapnik::query& q) const
{
	std::clog << "Rasterizer::features"
			<< ", resolution_type=(" << q.resolution().head << "," << q.resolution().tail.head << ")"
			<< ", scale_denominator=" << q.scale_denominator()
			<< ", bbox=[" << q.get_bbox().minx() << "," << q.get_bbox().miny() << "," << q.get_bbox().maxx() << "," << q.get_bbox().maxy() << "]"
			<< std::endl;

	double	resx=q.resolution().head,
			resy=q.resolution().tail.head,
			bbox_width=q.get_bbox().width(),
			bbox_height=q.get_bbox().height();

	int 	pixel_width=round(bbox_width * resx),
			pixel_height=round(bbox_height * resy);

	if (pixel_width<=0 || pixel_height<=0) {
		std::clog << "Illegal rasterizer display metrics" << std::endl;
		return mapnik::featureset_ptr();
	}

	std::clog << "Rasterizer generating image of size (" << pixel_width << "," << pixel_height << ")" << std::endl;

	// Setup for render
	mapnik::feature_ptr feature(mapnik::feature_factory::create(1));
	mapnik::image_data_32 image(pixel_width, pixel_height);
	rasterize_params params(q, image);

	rasterize(params);

	// Prepare and return the raster feature
	feature->set_raster(boost::make_shared<mapnik::raster>(q.get_bbox(), image));
	return boost::make_shared<singleton_featureset>(singleton_featureset(feature));
}

feature_ptr gdal_featureset::get_feature(mapnik::query const& q)
{
    feature_ptr feature = feature_factory::create(ctx_,1);

    GDALRasterBand * red = 0;
    GDALRasterBand * green = 0;
    GDALRasterBand * blue = 0;
    GDALRasterBand * alpha = 0;
    GDALRasterBand * grey = 0;

    /*
#ifdef MAPNIK_LOG
      double tr[6];
      dataset_.GetGeoTransform(tr);

      const double dx = tr[1];
      const double dy = tr[5];
      MAPNIK_LOG_DEBUG(gdal) << "gdal_featureset: dx_=" << dx_ << " dx=" << dx << " dy_=" << dy_ << "dy=" << dy;
#endif
    */

    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);

    MAPNIK_LOG_DEBUG(gdal) << "gdal_featureset: Raster extent=" << raster_extent_;
    MAPNIK_LOG_DEBUG(gdal) << "gdal_featureset: View extent=" << intersect;
    MAPNIK_LOG_DEBUG(gdal) << "gdal_featureset: Query resolution=" << boost::get<0>(q.resolution()) << "," << boost::get<1>(q.resolution());
    MAPNIK_LOG_DEBUG(gdal) << "gdal_featureset: StartX=" << x_off << " StartY=" << y_off << " Width=" << width << " Height=" << height;

    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_;

            MAPNIK_LOG_DEBUG(gdal) << "gdal_featureset: Applying layer filter_factor=" << filter_factor_;
        }
        // otherwise respect symbolizer level factor applied to query, default of 1.0
        else
        {
//.........这里部分代码省略.........

feature_ptr gdal_featureset::get_feature(mapnik::query const& q)
{
    feature_ptr feature = feature_factory::create(ctx_,1);
    int raster_has_nodata = 0;
    double raster_nodata = 0;
    GDALRasterBand * red = 0;
    GDALRasterBand * green = 0;
    GDALRasterBand * blue = 0;
    GDALRasterBand * alpha = 0;
    GDALRasterBand * grey = 0;
    CPLErr raster_io_error = CE_None;

    /*
#ifdef MAPNIK_LOG
      double tr[6];
      dataset_.GetGeoTransform(tr);

      const double dx = tr[1];
      const double dy = tr[5];
      MAPNIK_LOG_DEBUG(gdal) << "gdal_featureset: dx_=" << dx_ << " dx=" << dx << " dy_=" << dy_ << "dy=" << dy;
#endif
    */

    view_transform 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 / (std::fabs(dx_) * std::get<0>(q.resolution()));
    double margin_y = 1.0 / (std::fabs(dy_) * std::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);

    MAPNIK_LOG_DEBUG(gdal) << "gdal_featureset: Raster extent=" << raster_extent_;
    MAPNIK_LOG_DEBUG(gdal) << "gdal_featureset: View extent=" << intersect;
    MAPNIK_LOG_DEBUG(gdal) << "gdal_featureset: Query resolution=" << std::get<0>(q.resolution()) << "," << std::get<1>(q.resolution());
    MAPNIK_LOG_DEBUG(gdal) << "gdal_featureset: StartX=" << x_off << " StartY=" << y_off << " Width=" << width << " Height=" << height;

    if (width > 0 && height > 0)
    {
        double width_res = std::get<0>(q.resolution());
        double height_res = std::get<1>(q.resolution());
        int im_width = int(width_res * intersect.width() + 0.5);
        int im_height = int(height_res * intersect.height() + 0.5);

        double filter_factor = q.get_filter_factor();
        im_width = int(im_width * filter_factor + 0.5);
        im_height = int(im_height * filter_factor + 0.5);

        // 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;
//.........这里部分代码省略.........

feature_ptr rasterlite_featureset::get_feature(mapnik::query const& q)
{
#ifdef MAPNIK_DEBUG
   std::clog << "Rasterlite Plugin: get_feature" << "\n";
#endif

   feature_ptr feature(new Feature(1));

   double x0, y0, x1, y1;
   rasterliteGetExtent (dataset_, &x0, &y0, &x1, &y1);

   box2d<double> raster_extent(x0,y0,x1,y1); 
   box2d<double> intersect = raster_extent.intersect(q.get_bbox());

   int width = static_cast<int>(q.resolution() * intersect.width() + 0.5);
   int height = static_cast<int>(q.resolution() * intersect.height() + 0.5);

   double pixel_size = (intersect.width() >= intersect.height()) ?
       (intersect.width() / (double) width) : (intersect.height() / (double) height);

#ifdef MAPNIK_DEBUG         
   std::clog << "Rasterlite Plugin: Raster extent=" << raster_extent << "\n";
   std::clog << "Rasterlite Plugin: View extent=" << q.get_bbox() << "\n";
   std::clog << "Rasterlite Plugin: Intersect extent=" << intersect << "\n";
   std::clog << "Rasterlite Plugin: Query resolution=" << q.resolution() << "\n";
   std::clog << "Rasterlite Plugin: Size=" << width << " " << height << "\n";
   std::clog << "Rasterlite Plugin: Pixel Size=" << pixel_size << "\n";
#endif

   if (width > 0 && height > 0)
   {
      int size;
      void *raster;

      if (rasterliteGetRawImageByRect(dataset_,
            intersect.minx(), intersect.miny(), intersect.maxx(), intersect.maxy(),
            pixel_size, width, height, GAIA_RGBA_ARRAY, &raster, &size) == RASTERLITE_OK)
      {
          if (size > 0)
          {
              mapnik::image_data_32 image(width, height);
              image.set(0xffffffff);

              unsigned char* raster_data = static_cast<unsigned char*>(raster);
              unsigned char* image_data = image.getBytes();

              memcpy (image_data, raster_data, size);

              feature->set_raster(mapnik::raster_ptr(new mapnik::raster(intersect,image)));

              free (raster);

#ifdef MAPNIK_DEBUG         
              std::clog << "Rasterlite Plugin: Done" << "\n";
#endif
          }
          else
          {
#ifdef MAPNIK_DEBUG         
              std::clog << "Rasterlite Plugin: Error=" << rasterliteGetLastError (dataset_) << "\n";
#endif
          }
      }
      
      return feature;
   }
   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_;
        }
        // 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
//.........这里部分代码省略.........