Cleanup

src/HeightMap.cpp

@@ -1,7 +1,7 @@
 #include <gdal/cpl_conv.h>
 #include <iostream>
 #include <stdexcept>
-
+#include <omp.h>
 #include <gdal/gdal.h>
 #include "gdal/gdal_priv.h"
 #include <gdal/gdal_frmts.h>
@@ -49,3 +49,45 @@ float HeightMap::get_pixel(int x, int y)
     //std::cout << "  offset: " << offset << " " << x << ","<< y;
     return *(this->data + offset);
 }
+
+void HeightMap::blur(float standard_deviation)
+{
+    // standard_deviation does not do anything yet. This is currently a simple box blur
+    int kernel_height = 5;
+    int kernel_width = 5;
+    int kernel_size = kernel_height*kernel_width;
+    float* kernel = (float*) CPLMalloc(sizeof(float)*kernel_size);
+    for (int i=0; i<kernel_size; i++)
+    {
+        *(kernel + i) = 1.0;
+    }
+
+    float* blurred = (float *) CPLMalloc(sizeof(float)*this->width*this->height);
+    #pragma omp parallel
+    {
+    #pragma omp for
+    for (int i = 0; i < this->height * this->width; i++)
+    {
+        float blurred_pixel = 0;
+        for (int j = 0; j < kernel_size; j++)
+        {
+            int x = j%kernel_width - kernel_width/2 + i%this->width;
+            int y = j/kernel_width - kernel_height/2 + i/this->width;
+            if (x<0 || x>=this->width)
+            {
+                x = 0;
+            }
+            
+            if (y<0 || y>=this->height)
+            {
+                y = 0;
+            }
+            blurred_pixel += this->get_pixel(x, y);
+        }
+        *(blurred + i) = blurred_pixel/float(kernel_size);
+    }
+    }
+    free(this->data);
+    this->data = blurred;
+    blurred = nullptr;
+}

src/contour_creator.hh

@@ -19,6 +19,7 @@ class HeightMap
 
         HeightMap(const char* filepath);
         float get_pixel(int x,int y);
+        void blur(float standard_deviation);
 };
 
 /**

src/main.cpp

@@ -1,6 +1,9 @@
 #include "contour_creator.hh"
 #include <gdal/ogr_api.h>
 #include "ogrsf_frmts.h"
+#include <gdal/ogr_core.h>
+#include <gdal/ogr_feature.h>
+#include <gdal/ogr_geometry.h>
 #include <iostream>
 #include <ostream>
 #include <vector>
@@ -53,17 +56,36 @@ std::vector<CellMap> vector_cellmap(HeightMap* heightmap, int interval)
 std::tuple<double, double> local_to_projected(double* geotransform, int x, int y)
 {
     return {
-            geotransform[1] * x + geotransform[2] * y +
+        geotransform[1] * x + geotransform[2] * y +
-            geotransform[1] * 0.5 + geotransform[2] * 0.5 + geotransform[0],
+        geotransform[1] * 0.5 + geotransform[2] * 0.5 + geotransform[0],
-            geotransform[4] * x + geotransform[5] * y +
+        geotransform[4] * x + geotransform[5] * y +
-            geotransform[4] * 0.5 + geotransform[5] * 0.5 + geotransform[3]
+        geotransform[4] * 0.5 + geotransform[5] * 0.5 + geotransform[3]
-            };
+        };
 }
 
+constexpr std::tuple<double, double, double, double> marching_squares_lookup(int mcase)
+{
+    switch (mcase) {
+        case 1: return {0, 0.5, 0.5, 0};
+        case 2: return {1, 0.5, 0.5, 0};
+        case 3: return {0, 0.5, 1, 0};
+        case 4: return {0.5, 1, 1, 0.5};
+        case 5: return {0, 0, 0, 0}; //FIXME
+        case 6: return {0.5, 1, 0.5, 0};
+        case 7: return {0, 0.5, 0.5, 1};
+        case 8: return {0, 0.5, 0.5, 1};
+        case 9: return {0.5, 1, 0.5, 0};
+        case 10: return {0, 0, 0, 0}; //FIXME
+        case 11: return {0.5, 1, 1, 0.5};
+        case 12: return {0, 0.5, 1, 0.5};
+        case 13: return {0.5, 0, 1, 0.5};
+        case 14: return {0, 0.5, 0.5, 0};
+    };
+}
 void write_output_file(std::vector<CellMap> cellmaps, const char *filepath)
 {
 
-    const char *pszDriverName = "ESRI Shapefile";
+    const char *pszDriverName = "GeoJSON";
     GDALDriver *poDriver;
 
     GDALAllRegister();
@@ -86,7 +108,7 @@ void write_output_file(std::vector<CellMap> cellmaps, const char *filepath)
 
     OGRLayer *poLayer;
 
-    poLayer = poDS->CreateLayer( "contours", &(cellmaps[0]).reference_system, wkbPoint, NULL );
+    poLayer = poDS->CreateLayer( "contours", &(cellmaps[0]).reference_system, wkbLineString, NULL );
     if( poLayer == NULL )
     {
         printf( "Layer creation failed.\n" );
@@ -105,53 +127,44 @@ void write_output_file(std::vector<CellMap> cellmaps, const char *filepath)
     for (int j = 0; j < cellmaps.size(); j++)
     {
         CellMap* cellmap = &cellmaps[j];
-        for (int i = 0; i<cellmap->height*cellmap->width; i++) {
+
+        for (int i = 0; i < cellmap->height*cellmap->width; i++) 
+        {
             if (*(cellmap->cells + i) != 0 && *(cellmap->cells + i) != 15)
             {
-                OGRFeature *poFeature;
+                OGRFeature *feature;
-                poFeature = OGRFeature::CreateFeature( poLayer->GetLayerDefn() );
+                OGRLineString *geometry = new OGRLineString();
-                poFeature->SetField( "Name", *(cellmap->cells + i) );
+                feature = OGRFeature::CreateFeature( poLayer->GetLayerDefn() );
-
+                feature->SetField( "Name", j );
-                //OGRSpatialReference local;
-
-                //auto poCT = OGRCreateCoordinateTransformation( &local, &cellmap->reference_system );
-                
-                /*
-                if( poCT == NULL || !poCT->Transform( 1, &x, &y ) )
-                    printf( "Transformation failed.\n" );
-                */
-                OGRPoint pt;
-
                 int x_raw = i%cellmap->width;
                 int y_raw = i/cellmap->width;
                 auto [x, y] = local_to_projected(cellmap->geotransform, x_raw, y_raw);
+                auto [x_bl, y_bl, x_tr, y_tr] = marching_squares_lookup(*(cellmap->cells + i) );
+                //std::cout << x << ", " << y << "  ";
+                geometry->setPoint( geometry->getNumPoints(), x+x_tr*0.25, y+y_tr*0.25 ); 
+                geometry->setPoint( geometry->getNumPoints(), x+x_bl*0.25, y+y_bl*0.25 ); 
                 
-                pt.setX( x );
-                pt.setY( y );
 
-                poFeature->SetGeometry( &pt );
+                if ( feature->SetGeometry(geometry) != OGRERR_NONE)
-
+                {
-                if( poLayer->CreateFeature( poFeature ) != OGRERR_NONE )
+                    printf( "Failed to set geometry.\n" );
+                    exit( 1 );
+                }
+                OGRGeometryFactory::destroyGeometry(geometry);
+                if( poLayer->CreateFeature( feature ) != OGRERR_NONE )
                 {
                     printf( "Failed to create feature in shapefile.\n" );
                     exit( 1 );
                 }
+                OGRFeature::DestroyFeature( feature );  
+                    }
             
-                OGRFeature::DestroyFeature( poFeature );
-            }
         }
+        
+
     }
 
     GDALClose( poDS );
-    /*
-    OGRDataSourceH datasource = OGR_Dr_CreateDataSource(OGRGetDriverByName("GeoJSON"), "contour.geojson", new char*);
-    OGRSpatialReference reference_system = cellmap->reference_system;
-    OGRLayerH layer = OGR_DS_CreateLayer(datasource, "contour", &reference_system, wkbLineString25D, new char*);
-    
-    auto feature = OGR_F_Create(OGR_L_GetLayerDefn(static_cast<OGRLayerH>(layer)));
-
-    OGRGeometryH geometry = OGR_G_CreateGeometry(wkbLineString25D);
-    */
 }
 
 int main(int argc, const char* argv[])
@@ -162,20 +175,10 @@ int main(int argc, const char* argv[])
     std::cout << "x: " << map.width << "    y: " << map.height << "\n";
     std::cout << "max: " << map.max << "    min: " << map.min << "\n";
 
+    map.blur(0.8);
+    
     auto cellmap = produce_cellmap(&map, 40);
-    /*
-    for (int y = 0; y < cellmap.height; y++)
-    {
-        for (int x = 0; x < cellmap.width; x++)
-        {
-            if (cellmap.get_cell(x, y) && cellmap.get_cell(x, y)!=15) {
-                std::cout << x << ","<< y << "=" << cellmap.get_cell(x, y) << " ";
-            }
-        }
-       //std::cout << "\n";
-    }
-    */
     
     auto cellmaps = vector_cellmap(&map, 5);
-    write_output_file(cellmaps, "out.shp");
+    write_output_file(cellmaps, "out.geojson");
 }