Function agg2RenderPolygonHatched

mapagg.cpp:922–967

}

int agg2RenderPolygonHatched(imageObj *img, shapeObj *poly, double spacing, double width, double angle, colorObj *color) {
   
   msComputeBounds(poly);

   /* 
    * we create a hatch pattern that is the size of the shapeObj's bounds, expanded by the width 
    * of the stroke we want to apply to the lines to account for end-caps artifacts
    */
   int pw=(int)(poly->bounds.maxx-poly->bounds.minx+width*2)+1;
   int ph=(int)(poly->bounds.maxy-poly->bounds.miny+width*2)+1;

   //create a rectangular hatch of size pw,ph starting at 0,0
   //the created hatch is of the size of the shape's bounding box
   mapserver::path_storage hatch = createHatch(pw,ph,angle,spacing);
   
   //translate the hatch so it overlaps the current shape
   hatch.transform(mapserver::trans_affine_translation(poly->bounds.minx-width,poly->bounds.miny-width));



   //render the hatch clipped by the shape
   mapserver::conv_stroke <mapserver::path_storage > stroke(hatch);
   stroke.width(width);
   stroke.line_cap(mapserver::butt_cap);
   
   polygon_adaptor polygons(poly);
   
	AGG2Renderer *r = AGG_RENDERER(img);
   
   mapserver::rasterizer_scanline_aa<> ras1,ras2;
   mapserver::scanline_storage_aa8 storage;
   mapserver::scanline_storage_aa8 storage1;
   mapserver::scanline_storage_aa8 storage2;
   mapserver::scanline_p8 sl1,sl2;
   ras1.filling_rule(mapserver::fill_non_zero);
   ras1.add_path(stroke);                    
   mapserver::render_scanlines(ras1, r->sl_line, storage1);
   ras2.filling_rule(mapserver::fill_even_odd);
   ras2.add_path(polygons);
   mapserver::render_scanlines(ras2,r->sl_poly,storage2);
   mapserver::sbool_combine_shapes_aa(mapserver::sbool_and, storage1, storage2, sl1, sl2, r->sl_line, storage);
   r->m_renderer_scanline.color(aggColor(color));
   mapserver::render_scanlines ( storage, r->sl_poly, r->m_renderer_scanline );
   return MS_SUCCESS;

}

int msHatchPolygon(imageObj *img, shapeObj *poly, double spacing, double width, double angle, colorObj *color) {
   assert(MS_RENDERER_PLUGIN(img->format));