SF#3575828: Ensure new track drawing uses track property line thickness

[andy/viking.git] / src / vikdemlayer.c

diff --git a/src/vikdemlayer.c b/src/vikdemlayer.c
index a594260859fa54fd875fff3d18ab94159a76d58d..52c0b3dad19c116ed418daf58242876e9196030f 100644 (file)
--- a/src/vikdemlayer.c
+++ b/src/vikdemlayer.c
@@ -63,18 +63,19 @@
 
 #define SRTM_CACHE_TEMPLATE "%ssrtm3-%s%s%c%02d%c%03d.hgt.zip"
 #define SRTM_HTTP_SITE "dds.cr.usgs.gov"
 
 #define SRTM_CACHE_TEMPLATE "%ssrtm3-%s%s%c%02d%c%03d.hgt.zip"
 #define SRTM_HTTP_SITE "dds.cr.usgs.gov"

-#define SRTM_HTTP_URI  "/srtm/version2_1/SRTM3/OLD/"
+#define SRTM_HTTP_URI  "/srtm/version2_1/SRTM3/"

 
 #ifdef VIK_CONFIG_DEM24K
 #define DEM24K_DOWNLOAD_SCRIPT "dem24k.pl"
 #endif
 
 
 #ifdef VIK_CONFIG_DEM24K
 #define DEM24K_DOWNLOAD_SCRIPT "dem24k.pl"
 #endif
 

+#define UNUSED_LINE_THICKNESS 3

 
 

+static const gchar* dem_layer_tooltip( VikDEMLayer *vdl );

 static void dem_layer_marshall( VikDEMLayer *vdl, guint8 **data, gint *len );
 static VikDEMLayer *dem_layer_unmarshall( guint8 *data, gint len, VikViewport *vvp );
 static void dem_layer_marshall( VikDEMLayer *vdl, guint8 **data, gint *len );
 static VikDEMLayer *dem_layer_unmarshall( guint8 *data, gint len, VikViewport *vvp );

-static gboolean dem_layer_set_param ( VikDEMLayer *vdl, guint16 id, VikLayerParamData data, VikViewport *vp );
-static VikLayerParamData dem_layer_get_param ( VikDEMLayer *vdl, guint16 id );
-static void dem_layer_update_gc ( VikDEMLayer *vdl, VikViewport *vp, const gchar *color );
+static gboolean dem_layer_set_param ( VikDEMLayer *vdl, guint16 id, VikLayerParamData data, VikViewport *vp, gboolean is_file_operation );
+static VikLayerParamData dem_layer_get_param ( VikDEMLayer *vdl, guint16 id, gboolean is_file_operation );

 static void dem_layer_post_read ( VikLayer *vl, VikViewport *vp, gboolean from_file );
 static void srtm_draw_existence ( VikViewport *vp );
 
 static void dem_layer_post_read ( VikLayer *vl, VikViewport *vp, gboolean from_file );
 static void srtm_draw_existence ( VikViewport *vp );
 


@@ -82,10 +83,10 @@ static void srtm_draw_existence ( VikViewport *vp );
 static void dem24k_draw_existence ( VikViewport *vp );
 #endif
 
 static void dem24k_draw_existence ( VikViewport *vp );
 #endif
 

+/* Upped upper limit incase units are feet */

 static VikLayerParamScale param_scales[] = {
 static VikLayerParamScale param_scales[] = {

-  { 1, 10000, 10, 1 },
-  { 1, 10000, 10, 1 },
-  { 1, 10, 1, 0 },
+  { 0, 30000, 10, 1 },
+  { 1, 30000, 10, 1 },

 };
 
 static gchar *params_source[] = {
 };
 
 static gchar *params_source[] = {


@@ -93,7 +94,6 @@ static gchar *params_source[] = {
 #ifdef VIK_CONFIG_DEM24K
        "USA 10m (USGS 24k)",
 #endif
 #ifdef VIK_CONFIG_DEM24K
        "USA 10m (USGS 24k)",
 #endif

-        "None",

        NULL
        };
 
        NULL
        };
 


@@ -107,7 +107,6 @@ enum { DEM_SOURCE_SRTM,
 #ifdef VIK_CONFIG_DEM24K
        DEM_SOURCE_DEM24K,
 #endif
 #ifdef VIK_CONFIG_DEM24K
        DEM_SOURCE_DEM24K,
 #endif

-       DEM_SOURCE_NONE,

      };
 
 enum { DEM_TYPE_HEIGHT = 0,
      };
 
 enum { DEM_TYPE_HEIGHT = 0,


@@ -118,30 +117,34 @@ enum { DEM_TYPE_HEIGHT = 0,
 static VikLayerParam dem_layer_params[] = {
   { "files", VIK_LAYER_PARAM_STRING_LIST, VIK_LAYER_GROUP_NONE, N_("DEM Files:"), VIK_LAYER_WIDGET_FILELIST },
   { "source", VIK_LAYER_PARAM_UINT, VIK_LAYER_GROUP_NONE, N_("Download Source:"), VIK_LAYER_WIDGET_RADIOGROUP_STATIC, params_source, NULL },
 static VikLayerParam dem_layer_params[] = {
   { "files", VIK_LAYER_PARAM_STRING_LIST, VIK_LAYER_GROUP_NONE, N_("DEM Files:"), VIK_LAYER_WIDGET_FILELIST },
   { "source", VIK_LAYER_PARAM_UINT, VIK_LAYER_GROUP_NONE, N_("Download Source:"), VIK_LAYER_WIDGET_RADIOGROUP_STATIC, params_source, NULL },

-  { "color", VIK_LAYER_PARAM_STRING, VIK_LAYER_GROUP_NONE, N_("Color:"), VIK_LAYER_WIDGET_ENTRY },
+  { "color", VIK_LAYER_PARAM_COLOR, VIK_LAYER_GROUP_NONE, N_("Min Elev Color:"), VIK_LAYER_WIDGET_COLOR, 0 },

   { "type", VIK_LAYER_PARAM_UINT, VIK_LAYER_GROUP_NONE, N_("Type:"), VIK_LAYER_WIDGET_RADIOGROUP_STATIC, params_type, NULL },
   { "min_elev", VIK_LAYER_PARAM_DOUBLE, VIK_LAYER_GROUP_NONE, N_("Min Elev:"), VIK_LAYER_WIDGET_SPINBUTTON, param_scales + 0 },
   { "max_elev", VIK_LAYER_PARAM_DOUBLE, VIK_LAYER_GROUP_NONE, N_("Max Elev:"), VIK_LAYER_WIDGET_SPINBUTTON, param_scales + 0 },
   { "type", VIK_LAYER_PARAM_UINT, VIK_LAYER_GROUP_NONE, N_("Type:"), VIK_LAYER_WIDGET_RADIOGROUP_STATIC, params_type, NULL },
   { "min_elev", VIK_LAYER_PARAM_DOUBLE, VIK_LAYER_GROUP_NONE, N_("Min Elev:"), VIK_LAYER_WIDGET_SPINBUTTON, param_scales + 0 },
   { "max_elev", VIK_LAYER_PARAM_DOUBLE, VIK_LAYER_GROUP_NONE, N_("Max Elev:"), VIK_LAYER_WIDGET_SPINBUTTON, param_scales + 0 },

-  { "line_thickness", VIK_LAYER_PARAM_UINT, VIK_LAYER_GROUP_NONE, N_("Line Thickness:"), VIK_LAYER_WIDGET_SPINBUTTON, param_scales + 1 },

 };
 
 
 };
 
 

-enum { PARAM_FILES=0, PARAM_SOURCE, PARAM_COLOR, PARAM_TYPE, PARAM_MIN_ELEV, PARAM_MAX_ELEV, PARAM_LINE_THICKNESS, NUM_PARAMS };
+enum { PARAM_FILES=0, PARAM_SOURCE, PARAM_COLOR, PARAM_TYPE, PARAM_MIN_ELEV, PARAM_MAX_ELEV, NUM_PARAMS };

 
 static gpointer dem_layer_download_create ( VikWindow *vw, VikViewport *vvp);
 static gboolean dem_layer_download_release ( VikDEMLayer *vdl, GdkEventButton *event, VikViewport *vvp );
 static gboolean dem_layer_download_click ( VikDEMLayer *vdl, GdkEventButton *event, VikViewport *vvp );
 
 static VikToolInterface dem_tools[] = {
 
 static gpointer dem_layer_download_create ( VikWindow *vw, VikViewport *vvp);
 static gboolean dem_layer_download_release ( VikDEMLayer *vdl, GdkEventButton *event, VikViewport *vvp );
 static gboolean dem_layer_download_click ( VikDEMLayer *vdl, GdkEventButton *event, VikViewport *vvp );
 
 static VikToolInterface dem_tools[] = {

-  { N_("DEM Download/Import"), (VikToolConstructorFunc) dem_layer_download_create, NULL, NULL, NULL,
+  { { "DEMDownload", "vik-icon-DEM Download", N_("_DEM Download"), NULL, N_("DEM Download"), 0 },
+    (VikToolConstructorFunc) dem_layer_download_create, NULL, NULL, NULL,

     (VikToolMouseFunc) dem_layer_download_click, NULL,  (VikToolMouseFunc) dem_layer_download_release,
     (VikToolMouseFunc) dem_layer_download_click, NULL,  (VikToolMouseFunc) dem_layer_download_release,

-    (VikToolKeyFunc) NULL, GDK_CURSOR_IS_PIXMAP, &cursor_demdl_pixbuf },
+    (VikToolKeyFunc) NULL,
+    FALSE,
+    GDK_CURSOR_IS_PIXMAP, &cursor_demdl_pixbuf },

 };
 
 
 };
 
 

-/*
+/* HEIGHT COLORS
+   The first entry is blue for a default 'sea' colour,
+   however the value used by the corresponding gc can be configured as part of the DEM layer properties.
+   The other colours, shaded from brown to white are used to give an indication of height.

 */
 */

-

 static gchar *dem_height_colors[] = {
 "#0000FF",
 "#9b793c", "#9c7d40", "#9d8144", "#9e8549", "#9f894d", "#a08d51", "#a29156", "#a3955a", "#a4995e", "#a69d63",
 static gchar *dem_height_colors[] = {
 "#0000FF",
 "#9b793c", "#9c7d40", "#9d8144", "#9e8549", "#9f894d", "#a08d51", "#a29156", "#a3955a", "#a4995e", "#a69d63",


@@ -164,7 +167,7 @@ static const guint DEM_N_HEIGHT_COLORS = sizeof(dem_height_colors)/sizeof(dem_he
 */
 
 static gchar *dem_gradient_colors[] = {
 */
 
 static gchar *dem_gradient_colors[] = {

-"#AAAAAA"
+"#AAAAAA",

 "#000000", "#000011", "#000022", "#000033", "#000044", "#00004c", "#000055", "#00005d", "#000066", "#00006e",
 "#000077", "#00007f", "#000088", "#000090", "#000099", "#0000a1", "#0000aa", "#0000b2", "#0000bb", "#0000c3",
 "#0000cc", "#0000d4", "#0000dd", "#0000e5", "#0000ee", "#0000f6", "#0000ff", "#0008f7", "#0011ee", "#0019e6",
 "#000000", "#000011", "#000022", "#000033", "#000044", "#00004c", "#000055", "#00005d", "#000066", "#00006e",
 "#000077", "#00007f", "#000088", "#000090", "#000099", "#0000a1", "#0000aa", "#0000b2", "#0000bb", "#0000c3",
 "#0000cc", "#0000d4", "#0000dd", "#0000e5", "#0000ee", "#0000f6", "#0000ff", "#0008f7", "#0011ee", "#0019e6",


@@ -181,7 +184,8 @@ static const guint DEM_N_GRADIENT_COLORS = sizeof(dem_gradient_colors)/sizeof(de
 
 
 VikLayerInterface vik_dem_layer_interface = {
 
 
 VikLayerInterface vik_dem_layer_interface = {

-  "DEM",
+  N_("DEM"),
+  "<control><shift>D",

   &vikdemlayer_pixbuf,
 
   dem_tools,
   &vikdemlayer_pixbuf,
 
   dem_tools,


@@ -211,6 +215,9 @@ VikLayerInterface vik_dem_layer_interface = {
 
   (VikLayerFuncSublayerRenameRequest)   NULL,
   (VikLayerFuncSublayerToggleVisible)   NULL,
 
   (VikLayerFuncSublayerRenameRequest)   NULL,
   (VikLayerFuncSublayerToggleVisible)   NULL,

+  (VikLayerFuncSublayerTooltip)         NULL,
+  (VikLayerFuncLayerTooltip)            dem_layer_tooltip,
+  (VikLayerFuncLayerSelected)           NULL,

 
   (VikLayerFuncMarshall)               dem_layer_marshall,
   (VikLayerFuncUnmarshall)             dem_layer_unmarshall,
 
   (VikLayerFuncMarshall)               dem_layer_marshall,
   (VikLayerFuncUnmarshall)             dem_layer_unmarshall,


@@ -222,22 +229,26 @@ VikLayerInterface vik_dem_layer_interface = {
   (VikLayerFuncWriteFileData)           NULL,
 
   (VikLayerFuncDeleteItem)              NULL,
   (VikLayerFuncWriteFileData)           NULL,
 
   (VikLayerFuncDeleteItem)              NULL,

+  (VikLayerFuncCutItem)                 NULL,

   (VikLayerFuncCopyItem)                NULL,
   (VikLayerFuncPasteItem)               NULL,
   (VikLayerFuncFreeCopiedItem)          NULL,
   (VikLayerFuncDragDropRequest)                NULL,
   (VikLayerFuncCopyItem)                NULL,
   (VikLayerFuncPasteItem)               NULL,
   (VikLayerFuncFreeCopiedItem)          NULL,
   (VikLayerFuncDragDropRequest)                NULL,

+
+  (VikLayerFuncSelectClick)             NULL,
+  (VikLayerFuncSelectMove)              NULL,
+  (VikLayerFuncSelectRelease)           NULL,
+  (VikLayerFuncSelectedViewportMenu)    NULL,

 };
 
 struct _VikDEMLayer {
   VikLayer vl;
 };
 
 struct _VikDEMLayer {
   VikLayer vl;

-  GdkGC *gc;

   GdkGC **gcs;
   GdkGC **gcsgradient;
   GList *files;
   gdouble min_elev;
   gdouble max_elev;
   GdkGC **gcs;
   GdkGC **gcsgradient;
   GList *files;
   gdouble min_elev;
   gdouble max_elev;

-  guint8 line_thickness;
-  gchar *color;
+  GdkGC *color;

   guint source;
   guint type;
 };
   guint source;
   guint type;
 };


@@ -266,6 +277,13 @@ GType vik_dem_layer_get_type ()
   return vdl_type;
 }
 
   return vdl_type;
 }
 

+static const gchar* dem_layer_tooltip( VikDEMLayer *vdl )
+{
+  static gchar tmp_buf[100];
+  g_snprintf (tmp_buf, sizeof(tmp_buf), _("Number of files: %d"), g_list_length (vdl->files));
+  return tmp_buf;
+}
+

 static void dem_layer_marshall( VikDEMLayer *vdl, guint8 **data, gint *len )
 {
   vik_layer_marshall_params ( VIK_LAYER(vdl), data, len );
 static void dem_layer_marshall( VikDEMLayer *vdl, guint8 **data, gint *len )
 {
   vik_layer_marshall_params ( VIK_LAYER(vdl), data, len );


@@ -278,31 +296,104 @@ static VikDEMLayer *dem_layer_unmarshall( guint8 *data, gint len, VikViewport *v
 
   /* TODO: share GCS between layers */
   for ( i = 0; i < DEM_N_HEIGHT_COLORS; i++ )
 
   /* TODO: share GCS between layers */
   for ( i = 0; i < DEM_N_HEIGHT_COLORS; i++ )

-    rv->gcs[i] = vik_viewport_new_gc ( vvp, dem_height_colors[i], rv->line_thickness );
+    rv->gcs[i] = vik_viewport_new_gc ( vvp, dem_height_colors[i], UNUSED_LINE_THICKNESS );

 
   for ( i = 0; i < DEM_N_GRADIENT_COLORS; i++ )
 
   for ( i = 0; i < DEM_N_GRADIENT_COLORS; i++ )

-    rv->gcsgradient[i] = vik_viewport_new_gc ( vvp, dem_gradient_colors[i], rv->line_thickness );
+    rv->gcsgradient[i] = vik_viewport_new_gc ( vvp, dem_gradient_colors[i], UNUSED_LINE_THICKNESS );

 
   vik_layer_unmarshall_params ( VIK_LAYER(rv), data, len, vvp );
   return rv;
 }
 
 
   vik_layer_unmarshall_params ( VIK_LAYER(rv), data, len, vvp );
   return rv;
 }
 

-gboolean dem_layer_set_param ( VikDEMLayer *vdl, guint16 id, VikLayerParamData data, VikViewport *vp )
+/* Structure for DEM data used in background thread */
+typedef struct {
+  VikDEMLayer *vdl;
+} dem_load_thread_data;
+
+/*
+ * Function for starting the DEM file loading as a background thread
+ */
+static int dem_layer_load_list_thread ( dem_load_thread_data *dltd, gpointer threaddata )
+{
+  int result = 0; // Default to good
+  // Actual Load
+  if ( a_dems_load_list ( &(dltd->vdl->files), threaddata ) ) {
+    // Thread cancelled
+    result = -1;
+  }
+
+  // ATM as each file is processed the screen is not updated (no mechanism exposed to a_dems_load_list)
+  // Thus force draw only at the end, as loading is complete/aborted
+  //gdk_threads_enter();
+  // Test is helpful to prevent Gtk-CRITICAL warnings if the program is exitted whilst loading
+  if ( IS_VIK_LAYER(dltd->vdl) )
+    vik_layer_emit_update ( VIK_LAYER(dltd->vdl), TRUE ); // Yes update from background thread
+  //gdk_threads_leave();
+
+  return result;
+}
+
+static void dem_layer_thread_data_free ( dem_load_thread_data *data )
+{
+  // Simple release
+  g_free ( data );
+}
+
+static void dem_layer_thread_cancel ( dem_load_thread_data *data )
+{
+  // Abort loading
+  // Instead of freeing the list, leave it as partially processed
+  // Thus we can see/use what was done
+}
+
+gboolean dem_layer_set_param ( VikDEMLayer *vdl, guint16 id, VikLayerParamData data, VikViewport *vp, gboolean is_file_operation )

 {
   switch ( id )
   {
 {
   switch ( id )
   {

-    case PARAM_COLOR: if ( vdl->color ) g_free ( vdl->color ); vdl->color = g_strdup ( data.s ); break;
+    case PARAM_COLOR: gdk_gc_set_rgb_fg_color ( vdl->gcs[0], &(data.c) ); break;

     case PARAM_SOURCE: vdl->source = data.u; break;
     case PARAM_TYPE: vdl->type = data.u; break;
     case PARAM_SOURCE: vdl->source = data.u; break;
     case PARAM_TYPE: vdl->type = data.u; break;

-    case PARAM_MIN_ELEV: vdl->min_elev = data.d; break;
-    case PARAM_MAX_ELEV: vdl->max_elev = data.d; break;
-    case PARAM_LINE_THICKNESS: if ( data.u >= 1 && data.u <= 15 ) vdl->line_thickness = data.u; break;
-    case PARAM_FILES: a_dems_load_list ( &(data.sl) ); a_dems_list_free ( vdl->files ); vdl->files = data.sl; break;
+    case PARAM_MIN_ELEV:
+      /* Convert to store internally
+         NB file operation always in internal units (metres) */
+      if (!is_file_operation && a_vik_get_units_height () == VIK_UNITS_HEIGHT_FEET )
+        vdl->min_elev = VIK_FEET_TO_METERS(data.d);
+      else
+        vdl->min_elev = data.d;
+      break;
+    case PARAM_MAX_ELEV:
+      /* Convert to store internally
+         NB file operation always in internal units (metres) */
+      if (!is_file_operation && a_vik_get_units_height () == VIK_UNITS_HEIGHT_FEET )
+        vdl->max_elev = VIK_FEET_TO_METERS(data.d);
+      else
+        vdl->max_elev = data.d;
+      break;
+    case PARAM_FILES:
+    {
+      // Clear out old settings - if any commonalities with new settings they will have to be read again
+      a_dems_list_free ( vdl->files );
+      // Set file list so any other intermediate screen drawing updates will show currently loaded DEMs by the working thread
+      vdl->files = data.sl;
+      // Thread Load
+      dem_load_thread_data *dltd = g_malloc ( sizeof(dem_load_thread_data) );
+      dltd->vdl = vdl;
+      dltd->vdl->files = data.sl;
+
+      a_background_thread ( VIK_GTK_WINDOW_FROM_WIDGET(vp),
+                           _("DEM Loading"),
+                           (vik_thr_func) dem_layer_load_list_thread,
+                           dltd,
+                           (vik_thr_free_func) dem_layer_thread_data_free,
+                           (vik_thr_free_func) dem_layer_thread_cancel,
+                           g_list_length ( data.sl ) ); // Number of DEM files
+      break;
+    }

   }
   return TRUE;
 }
 
   }
   return TRUE;
 }
 

-static VikLayerParamData dem_layer_get_param ( VikDEMLayer *vdl, guint16 id )
+static VikLayerParamData dem_layer_get_param ( VikDEMLayer *vdl, guint16 id, gboolean is_file_operation )

 {
   VikLayerParamData rv;
   switch ( id )
 {
   VikLayerParamData rv;
   switch ( id )


@@ -310,21 +401,30 @@ static VikLayerParamData dem_layer_get_param ( VikDEMLayer *vdl, guint16 id )
     case PARAM_FILES: rv.sl = vdl->files; break;
     case PARAM_SOURCE: rv.u = vdl->source; break;
     case PARAM_TYPE: rv.u = vdl->type; break;
     case PARAM_FILES: rv.sl = vdl->files; break;
     case PARAM_SOURCE: rv.u = vdl->source; break;
     case PARAM_TYPE: rv.u = vdl->type; break;

-    case PARAM_COLOR: rv.s = vdl->color ? vdl->color : ""; break;
-    case PARAM_MIN_ELEV: rv.d = vdl->min_elev; break;
-    case PARAM_MAX_ELEV: rv.d = vdl->max_elev; break;
-    case PARAM_LINE_THICKNESS: rv.i = vdl->line_thickness; break;
+    case PARAM_COLOR: vik_gc_get_fg_color ( vdl->gcs[0], &(rv.c) ); break;
+    case PARAM_MIN_ELEV:
+      /* Convert for display in desired units
+         NB file operation always in internal units (metres) */
+      if (!is_file_operation && a_vik_get_units_height () == VIK_UNITS_HEIGHT_FEET )
+        rv.d = VIK_METERS_TO_FEET(vdl->min_elev);
+      else
+        rv.d = vdl->min_elev;
+      break;
+    case PARAM_MAX_ELEV:
+      /* Convert for display in desired units
+         NB file operation always in internal units (metres) */
+      if (!is_file_operation && a_vik_get_units_height () == VIK_UNITS_HEIGHT_FEET )
+        rv.d = VIK_METERS_TO_FEET(vdl->max_elev);
+      else
+        rv.d = vdl->max_elev;
+      break;

   }
   return rv;
 }
 
 static void dem_layer_post_read ( VikLayer *vl, VikViewport *vp, gboolean from_file )
 {
   }
   return rv;
 }
 
 static void dem_layer_post_read ( VikLayer *vl, VikViewport *vp, gboolean from_file )
 {

-  VikDEMLayer *vdl = VIK_DEM_LAYER(vl);
-  if ( vdl->gc )
-    g_object_unref ( G_OBJECT(vdl->gc) );
-
-  vdl->gc = vik_viewport_new_gc ( vp, vdl->color, vdl->line_thickness );
+  /* nothing ATM, but keep in case it's needed the future */

 }
 
 VikDEMLayer *vik_dem_layer_new ( )
 }
 
 VikDEMLayer *vik_dem_layer_new ( )


@@ -335,9 +435,6 @@ VikDEMLayer *vik_dem_layer_new ( )
 
   vdl->files = NULL;
 
 
   vdl->files = NULL;
 

-
-  vdl->gc = NULL;
-

   vdl->gcs = g_malloc(sizeof(GdkGC *)*DEM_N_HEIGHT_COLORS);
   vdl->gcsgradient = g_malloc(sizeof(GdkGC *)*DEM_N_GRADIENT_COLORS);
   /* make new gcs only if we need it (copy layer -> use old) */
   vdl->gcs = g_malloc(sizeof(GdkGC *)*DEM_N_HEIGHT_COLORS);
   vdl->gcsgradient = g_malloc(sizeof(GdkGC *)*DEM_N_GRADIENT_COLORS);
   /* make new gcs only if we need it (copy layer -> use old) */


@@ -346,20 +443,25 @@ VikDEMLayer *vik_dem_layer_new ( )
   vdl->max_elev = 1000.0;
   vdl->source = DEM_SOURCE_SRTM;
   vdl->type = DEM_TYPE_HEIGHT;
   vdl->max_elev = 1000.0;
   vdl->source = DEM_SOURCE_SRTM;
   vdl->type = DEM_TYPE_HEIGHT;

-  vdl->line_thickness = 3;
-  vdl->color = NULL;

   return vdl;
 }
 
 
   return vdl;
 }
 
 

+static inline guint16 get_height_difference(gint16 elev, gint16 new_elev)
+{
+  if(new_elev == VIK_DEM_INVALID_ELEVATION)
+    return 0;
+  else
+    return abs(new_elev - elev);
+}
+

 
 static void vik_dem_layer_draw_dem ( VikDEMLayer *vdl, VikViewport *vp, VikDEM *dem )
 {
 
 static void vik_dem_layer_draw_dem ( VikDEMLayer *vdl, VikViewport *vp, VikDEM *dem )
 {

-  VikDEMColumn *column;
-  VikDEMColumn *nextcolumn;
+  VikDEMColumn *column, *prevcolumn, *nextcolumn;

 
   struct LatLon dem_northeast, dem_southwest;
 
   struct LatLon dem_northeast, dem_southwest;

-  gdouble max_lat, max_lon, min_lat, min_lon;  
+  gdouble max_lat, max_lon, min_lat, min_lon;

 
   /**** Check if viewport and DEM data overlap ****/
 
 
   /**** Check if viewport and DEM data overlap ****/
 


@@ -436,7 +538,7 @@ static void vik_dem_layer_draw_dem ( VikDEMLayer *vdl, VikViewport *vp, VikDEM *
 
     gint16 elev;
 
 
     gint16 elev;
 

-    guint skip_factor = ceil ( vik_viewport_get_xmpp(vp) / 40 ); /* todo: smarter calculation. */
+    guint skip_factor = ceil ( vik_viewport_get_xmpp(vp) / 80 ); /* todo: smarter calculation. */

 
     gdouble nscale_deg = dem->north_scale / ((gdouble) 3600);
     gdouble escale_deg = dem->east_scale / ((gdouble) 3600);
 
     gdouble nscale_deg = dem->north_scale / ((gdouble) 3600);
     gdouble escale_deg = dem->east_scale / ((gdouble) 3600);


@@ -457,96 +559,126 @@ static void vik_dem_layer_draw_dem ( VikDEMLayer *vdl, VikViewport *vp, VikDEM *
     end_lon   = ceil (end_lon_as / dem->east_scale) * escale_deg;
 
     vik_dem_east_north_to_xy ( dem, start_lon_as, start_lat_as, &start_x, &start_y );
     end_lon   = ceil (end_lon_as / dem->east_scale) * escale_deg;
 
     vik_dem_east_north_to_xy ( dem, start_lon_as, start_lat_as, &start_x, &start_y );

+    guint gradient_skip_factor = 1;
+    if(vdl->type == DEM_TYPE_GRADIENT)
+           gradient_skip_factor = skip_factor;

 
     /* verify sane elev interval */
     if ( vdl->max_elev <= vdl->min_elev )
       vdl->max_elev = vdl->min_elev + 1;
 
 
     /* verify sane elev interval */
     if ( vdl->max_elev <= vdl->min_elev )
       vdl->max_elev = vdl->min_elev + 1;
 

-    for ( x=start_x, counter.lon = start_lon; counter.lon <= end_lon; counter.lon += escale_deg * skip_factor, x += skip_factor ) {
-      if ( x > 0 && x < dem->n_columns ) {
+    for ( x=start_x, counter.lon = start_lon; counter.lon <= end_lon+escale_deg*skip_factor; counter.lon += escale_deg * skip_factor, x += skip_factor ) {
+      // NOTE: ( counter.lon <= end_lon + ESCALE_DEG*SKIP_FACTOR ) is neccessary so in high zoom modes,
+      // the leftmost column does also get drawn, if the center point is out of viewport.
+      if ( x >= 0 && x < dem->n_columns ) {

         column = g_ptr_array_index ( dem->columns, x );
         column = g_ptr_array_index ( dem->columns, x );

-       if(x+1 == dem->n_columns) {
-         nextcolumn = g_ptr_array_index ( dem->columns, x-1);
-       } else {
-         nextcolumn = g_ptr_array_index ( dem->columns, x+1);
-       }
+        // get previous and next column. catch out-of-bound.
+       gint32 new_x = x;
+       new_x -= gradient_skip_factor;
+        if(new_x < 1)
+          prevcolumn = g_ptr_array_index ( dem->columns, x+1);
+        else
+          prevcolumn = g_ptr_array_index ( dem->columns, new_x);
+       new_x = x;
+       new_x += gradient_skip_factor;
+        if(new_x >= dem->n_columns)
+          nextcolumn = g_ptr_array_index ( dem->columns, x-1);
+        else
+          nextcolumn = g_ptr_array_index ( dem->columns, new_x);

 
         for ( y=start_y, counter.lat = start_lat; counter.lat <= end_lat; counter.lat += nscale_deg * skip_factor, y += skip_factor ) {
           if ( y > column->n_points )
             break;
 
         for ( y=start_y, counter.lat = start_lat; counter.lat <= end_lat; counter.lat += nscale_deg * skip_factor, y += skip_factor ) {
           if ( y > column->n_points )
             break;

+

           elev = column->points[y];
 
           elev = column->points[y];
 

-         if(vdl->type == DEM_TYPE_HEIGHT) {
-                 if ( elev != VIK_DEM_INVALID_ELEVATION && elev < vdl->min_elev )
-                   elev=vdl->min_elev;
-                 if ( elev != VIK_DEM_INVALID_ELEVATION && elev > vdl->max_elev )
-                   elev=vdl->max_elev;
-         }
+         // calculate bounding box for drawing
+         gint box_x, box_y, box_width, box_height;
+         struct LatLon box_c;
+         box_c = counter;
+         box_c.lat += (nscale_deg * skip_factor)/2;
+          box_c.lon -= (escale_deg * skip_factor)/2;
+         vik_coord_load_from_latlon(&tmp, vik_viewport_get_coord_mode(vp), &box_c);
+         vik_viewport_coord_to_screen(vp, &tmp, &box_x, &box_y);
+         // catch box at borders
+         if(box_x < 0)
+                 box_x = 0;
+         if(box_y < 0)
+                 box_y = 0;
+          box_c.lat -= nscale_deg * skip_factor;
+         box_c.lon += escale_deg * skip_factor;
+         vik_coord_load_from_latlon(&tmp, vik_viewport_get_coord_mode(vp), &box_c);
+         vik_viewport_coord_to_screen(vp, &tmp, &box_width, &box_height);
+         box_width -= box_x;
+         box_height -= box_y;
+          // catch box at borders
+         if(box_width < 0 || box_height < 0)
+                 continue; // skip this. this is out of our viewport anyway. FIXME: why?
+
+         gboolean below_minimum = FALSE;
+          if(vdl->type == DEM_TYPE_HEIGHT) {
+            if ( elev != VIK_DEM_INVALID_ELEVATION && elev < vdl->min_elev ) {
+              // Prevent 'elev - vdl->min_elev' from being negative so can safely use as array index
+              elev = ceil ( vdl->min_elev );
+             below_minimum = TRUE;
+           }
+            if ( elev != VIK_DEM_INVALID_ELEVATION && elev > vdl->max_elev )
+              elev = vdl->max_elev;
+          }

 
           {
 
           {

-            gint a, b;
-
-            vik_coord_load_from_latlon(&tmp, vik_viewport_get_coord_mode(vp), &counter);
-            vik_viewport_coord_to_screen(vp, &tmp, &a, &b);
-           if(vdl->type == DEM_TYPE_GRADIENT) {
-                   if( elev == VIK_DEM_INVALID_ELEVATION ) {
-                           /* don't draw it */
-                   } else {
-                           // calculate gradient, but only in two orthogonal directions.
-                           gint16 change = 0;
-                           gint16 newelev;
-
-                           // down
-                           if(y+1 == column->n_points)
-                                   newelev = column->points[y-1];
-                           else
-                                   newelev = column->points[y+1];
-                           if(newelev != VIK_DEM_INVALID_ELEVATION)
-                                   change += abs(newelev - elev);
-
-                           // down + right
-                           if(y+1 == nextcolumn->n_points)
-                                   newelev = nextcolumn->points[y-1];
-                           else
-                                   newelev = nextcolumn->points[y+1];
-                           if(newelev != VIK_DEM_INVALID_ELEVATION)
-                                   change += abs(newelev - elev);
-
-                           // right
-                           newelev = nextcolumn->points[y];
-                           if(newelev != VIK_DEM_INVALID_ELEVATION)
-                                   change += abs(newelev - elev);
-
-                           // up + right
-                           if(y <= 1)
-                                   newelev = nextcolumn->points[y+1];
-                           else
-                                   newelev = nextcolumn->points[y-1];
-                           if(newelev != VIK_DEM_INVALID_ELEVATION)
-                                   change += abs(newelev - elev);
-
-                           change = log(change) * log(change) * log(change);
-
-                           if(change < vdl->min_elev)
-                                   change = vdl->min_elev;
-
-                           if(change > vdl->max_elev)
-                                   change = vdl->max_elev;
-
-                           // void vik_viewport_draw_rectangle ( VikViewport *vvp, GdkGC *gc, gboolean filled, gint x1, gint y1, gint x2, gint y2 );
-                           vik_viewport_draw_rectangle(vp, vdl->gcsgradient[(gint)floor((change - vdl->min_elev)/(vdl->max_elev - vdl->min_elev)*(DEM_N_GRADIENT_COLORS-2))+1], TRUE, a-2, b-2, 4, 4 );
-                   }
+           if(box_width < 0 || box_height < 0) // FIXME: why does this happen?
+              continue;
+
+            if(vdl->type == DEM_TYPE_GRADIENT) {
+              if( elev == VIK_DEM_INVALID_ELEVATION ) {
+                /* don't draw it */
+              } else {
+                // calculate and sum gradient in all directions
+                gint16 change = 0;
+               gint32 new_y;
+
+               // calculate gradient from height points all around the current one
+               new_y = y - gradient_skip_factor;
+               if(new_y < 0)
+                       new_y = y;
+               change += get_height_difference(elev, prevcolumn->points[new_y]);
+               change += get_height_difference(elev, column->points[new_y]);
+               change += get_height_difference(elev, nextcolumn->points[new_y]);
+
+               change += get_height_difference(elev, prevcolumn->points[y]);
+               change += get_height_difference(elev, nextcolumn->points[y]);
+
+               new_y = y + gradient_skip_factor;
+               if(new_y >= column->n_points)
+                       new_y = y;
+               change += get_height_difference(elev, prevcolumn->points[new_y]);
+               change += get_height_difference(elev, column->points[new_y]);
+               change += get_height_difference(elev, nextcolumn->points[new_y]);
+
+               change = change / ((skip_factor > 1) ? log(skip_factor) : 0.55); // FIXME: better calc.
+
+                if(change < vdl->min_elev)
+                  // Prevent 'change - vdl->min_elev' from being negative so can safely use as array index
+                  change = ceil ( vdl->min_elev );
+
+                if(change > vdl->max_elev)
+                  change = vdl->max_elev;
+
+                // void vik_viewport_draw_rectangle ( VikViewport *vvp, GdkGC *gc, gboolean filled, gint x1, gint y1, gint x2, gint y2 );
+                vik_viewport_draw_rectangle(vp, vdl->gcsgradient[(gint)floor(((change - vdl->min_elev)/(vdl->max_elev - vdl->min_elev))*(DEM_N_GRADIENT_COLORS-2))+1], TRUE, box_x, box_y, box_width, box_height);
+              }

             } else {
             } else {

-                   if(vdl->type == DEM_TYPE_HEIGHT) {
-                           if ( elev == VIK_DEM_INVALID_ELEVATION )
-                             ; /* don't draw it */
-                           else if ( elev <= 0 )
-                             vik_viewport_draw_rectangle(vp, vdl->gcs[0], TRUE, a-2, b-2, 4, 4 );
-                           else
-                             vik_viewport_draw_rectangle(vp, vdl->gcs[(gint)floor((elev - vdl->min_elev)/(vdl->max_elev - vdl->min_elev)*(DEM_N_HEIGHT_COLORS-2))+1], TRUE, a-2, b-2, 4, 4 );
-                   }
-           }
-
+              if(vdl->type == DEM_TYPE_HEIGHT) {
+                if ( elev == VIK_DEM_INVALID_ELEVATION )
+                  ; /* don't draw it */
+                else if ( elev <= 0 || below_minimum )
+                 /* If 'sea' colour or below the defined mininum draw in the configurable colour */
+                  vik_viewport_draw_rectangle(vp, vdl->gcs[0], TRUE, box_x, box_y, box_width, box_height);
+                else
+                  vik_viewport_draw_rectangle(vp, vdl->gcs[(gint)floor(((elev - vdl->min_elev)/(vdl->max_elev - vdl->min_elev))*(DEM_N_HEIGHT_COLORS-2))+1], TRUE, box_x, box_y, box_width, box_height);
+              }
+            }

           }
         } /* for y= */
       }
           }
         } /* for y= */
       }


@@ -628,9 +760,9 @@ static void vik_dem_layer_draw_dem ( VikDEMLayer *vdl, VikViewport *vp, VikDEM *
             if ( elev == VIK_DEM_INVALID_ELEVATION )
               ; /* don't draw it */
             else if ( elev <= 0 )
             if ( elev == VIK_DEM_INVALID_ELEVATION )
               ; /* don't draw it */
             else if ( elev <= 0 )

-              vik_viewport_draw_rectangle(vp, vdl->gcs[0], TRUE, a-2, b-2, 4, 4 );
+              vik_viewport_draw_rectangle(vp, vdl->gcs[0], TRUE, a-1, b-1, 2, 2 );

             else
             else

-              vik_viewport_draw_rectangle(vp, vdl->gcs[(gint)floor((elev - vdl->min_elev)/(vdl->max_elev - vdl->min_elev)*(DEM_N_HEIGHT_COLORS-2))+1], TRUE, a-2, b-2, 4, 4 );
+              vik_viewport_draw_rectangle(vp, vdl->gcs[(gint)floor((elev - vdl->min_elev)/(vdl->max_elev - vdl->min_elev)*(DEM_N_HEIGHT_COLORS-2))+1], TRUE, a-1, b-1, 2, 2 );

           }
         } /* for y= */
       }
           }
         } /* for y= */
       }


@@ -695,11 +827,8 @@ void vik_dem_layer_draw ( VikDEMLayer *vdl, gpointer data )
 void vik_dem_layer_free ( VikDEMLayer *vdl )
 {
   gint i;
 void vik_dem_layer_free ( VikDEMLayer *vdl )
 {
   gint i;

-  if ( vdl->gc != NULL )
-    g_object_unref ( G_OBJECT(vdl->gc) );
-

   if ( vdl->color != NULL )
   if ( vdl->color != NULL )

-    g_free ( vdl->color );
+    g_object_unref ( vdl->color );

 
   if ( vdl->gcs )
     for ( i = 0; i < DEM_N_HEIGHT_COLORS; i++ )
 
   if ( vdl->gcs )
     for ( i = 0; i < DEM_N_HEIGHT_COLORS; i++ )


@@ -714,19 +843,6 @@ void vik_dem_layer_free ( VikDEMLayer *vdl )
   a_dems_list_free ( vdl->files );
 }
 
   a_dems_list_free ( vdl->files );
 }
 

-static void dem_layer_update_gc ( VikDEMLayer *vdl, VikViewport *vp, const gchar *color )
-{
-  if ( vdl->color )
-    g_free ( vdl->color );
-
-  vdl->color = g_strdup ( color );
-
-  if ( vdl->gc )
-    g_object_unref ( G_OBJECT(vdl->gc) );
-
-  vdl->gc = vik_viewport_new_gc ( vp, vdl->color, vdl->line_thickness );
-}
-

 VikDEMLayer *vik_dem_layer_create ( VikViewport *vp )
 {
   VikDEMLayer *vdl = vik_dem_layer_new ();
 VikDEMLayer *vik_dem_layer_create ( VikViewport *vp )
 {
   VikDEMLayer *vdl = vik_dem_layer_new ();


@@ -734,12 +850,11 @@ VikDEMLayer *vik_dem_layer_create ( VikViewport *vp )
 
   /* TODO: share GCS between layers */
   for ( i = 0; i < DEM_N_HEIGHT_COLORS; i++ )
 
   /* TODO: share GCS between layers */
   for ( i = 0; i < DEM_N_HEIGHT_COLORS; i++ )

-    vdl->gcs[i] = vik_viewport_new_gc ( vp, dem_height_colors[i], vdl->line_thickness );
+    vdl->gcs[i] = vik_viewport_new_gc ( vp, dem_height_colors[i], UNUSED_LINE_THICKNESS );

 
   for ( i = 0; i < DEM_N_GRADIENT_COLORS; i++ )
 
   for ( i = 0; i < DEM_N_GRADIENT_COLORS; i++ )

-    vdl->gcsgradient[i] = vik_viewport_new_gc ( vp, dem_gradient_colors[i], vdl->line_thickness );
+    vdl->gcsgradient[i] = vik_viewport_new_gc ( vp, dem_gradient_colors[i], UNUSED_LINE_THICKNESS );

 
 

-  dem_layer_update_gc ( vdl, vp, "red" );

   return vdl;
 }
 /**************************************************************
   return vdl;
 }
 /**************************************************************


@@ -782,7 +897,7 @@ static void srtm_dem_download_thread ( DEMDownloadParams *p, gpointer threaddata
                (intlon >= 0) ? 'E' : 'W',
                ABS(intlon) );
 
                (intlon >= 0) ? 'E' : 'W',
                ABS(intlon) );
 

-  static DownloadOptions options = { 0, NULL, 0, a_check_map_file };
+  static DownloadMapOptions options = { FALSE, FALSE, NULL, 0, a_check_map_file };

   a_http_download_get_url ( SRTM_HTTP_SITE, src_fn, p->dest, &options, NULL );
   g_free ( src_fn );
 }
   a_http_download_get_url ( SRTM_HTTP_SITE, src_fn, p->dest, &options, NULL );
   g_free ( src_fn );
 }


@@ -867,6 +982,7 @@ static void dem24k_dem_download_thread ( DEMDownloadParams *p, gpointer threadda
        ceil(p->lon*8)/8 );
   /* FIX: don't use system, use execv or something. check for existence */
   system(cmdline);
        ceil(p->lon*8)/8 );
   /* FIX: don't use system, use execv or something. check for existence */
   system(cmdline);

+  g_free ( cmdline );

 }
 
 static gchar *dem24k_lat_lon_to_dest_fn ( gdouble lat, gdouble lon )
 }
 
 static gchar *dem24k_lat_lon_to_dest_fn ( gdouble lat, gdouble lon )


@@ -957,7 +1073,6 @@ static gboolean dem_layer_add_file ( VikDEMLayer *vdl, const gchar *full_path )
       vdl->files = g_list_prepend ( vdl->files, duped_path );
       a_dems_load ( duped_path );
       g_debug("%s: %s", __FUNCTION__, duped_path);
       vdl->files = g_list_prepend ( vdl->files, duped_path );
       a_dems_load ( duped_path );
       g_debug("%s: %s", __FUNCTION__, duped_path);

-      vik_layer_emit_update ( VIK_LAYER(vdl) );

     }
     return TRUE;
   } else
     }
     return TRUE;
   } else


@@ -972,17 +1087,19 @@ static void dem_download_thread ( DEMDownloadParams *p, gpointer threaddata )
   else if ( p->source == DEM_SOURCE_DEM24K )
     dem24k_dem_download_thread ( p, threaddata );
 #endif
   else if ( p->source == DEM_SOURCE_DEM24K )
     dem24k_dem_download_thread ( p, threaddata );
 #endif

+  else
+    return;

 
 

-  gdk_threads_enter();
+  //gdk_threads_enter();

   g_mutex_lock ( p->mutex );
   if ( p->vdl ) {
     g_object_weak_unref ( G_OBJECT(p->vdl), weak_ref_cb, p );
 
     if ( dem_layer_add_file ( p->vdl, p->dest ) )
   g_mutex_lock ( p->mutex );
   if ( p->vdl ) {
     g_object_weak_unref ( G_OBJECT(p->vdl), weak_ref_cb, p );
 
     if ( dem_layer_add_file ( p->vdl, p->dest ) )

-      vik_layer_emit_update ( VIK_LAYER(p->vdl) );
+      vik_layer_emit_update ( VIK_LAYER(p->vdl), TRUE ); // Yes update from background thread

   }
   g_mutex_unlock ( p->mutex );
   }
   g_mutex_unlock ( p->mutex );

-  gdk_threads_leave();
+  //gdk_threads_leave();

 }
 
 
 }
 
 


@@ -1007,9 +1124,6 @@ static gboolean dem_layer_download_release ( VikDEMLayer *vdl, GdkEventButton *e
   gchar *full_path;
   gchar *dem_file = NULL;
 
   gchar *full_path;
   gchar *dem_file = NULL;
 

-  if ( vdl->source == DEM_SOURCE_NONE )
-    a_dialog_error_msg ( VIK_GTK_WINDOW_FROM_LAYER(vdl), _("No download source selected. Edit layer properties.") );
-

   vik_viewport_screen_to_coord ( vvp, event->x, event->y, &coord );
   vik_coord_to_latlon ( &coord, &ll );
 
   vik_viewport_screen_to_coord ( vvp, event->x, event->y, &coord );
   vik_coord_to_latlon ( &coord, &ll );
 


@@ -1044,7 +1158,11 @@ static gboolean dem_layer_download_release ( VikDEMLayer *vdl, GdkEventButton *e
     a_background_thread ( VIK_GTK_WINDOW_FROM_LAYER(vdl), tmp,
                (vik_thr_func) dem_download_thread, p,
                (vik_thr_free_func) free_dem_download_params, NULL, 1 );
     a_background_thread ( VIK_GTK_WINDOW_FROM_LAYER(vdl), tmp,
                (vik_thr_func) dem_download_thread, p,
                (vik_thr_free_func) free_dem_download_params, NULL, 1 );

+
+    g_free ( tmp );

   }
   }

+  else
+    vik_layer_emit_update ( VIK_LAYER(vdl), FALSE );

 
   g_free ( dem_file );
   g_free ( full_path );
 
   g_free ( dem_file );
   g_free ( full_path );