Pileus Git - grits/blob - src/plugins/srtm.c

   1 /*
   2  * Copyright (C) 2009 Andy Spencer <spenceal@rose-hulman.edu>
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include <gtk/gtkgl.h>
  19 #include <GL/gl.h>
  20
  21 #include <gis.h>
  22
  23 #include "srtm.h"
  24
  25 #define MAX_RESOLUTION 500
  26 #define TILE_WIDTH     1024
  27 #define TILE_HEIGHT    512
  28
  29 struct _TileData {
  30         /* OpenGL has to be first to make gis_opengl_render_tiles happy */
  31         guint      opengl;
  32         guint16   *bil;
  33 };
  34
  35 static gdouble _height_func(gdouble lat, gdouble lon, gpointer _self)
  36 {
  37         GisPluginSrtm *self = _self;
  38         if (!self) return 0;
  39
  40         GisTile *tile = gis_tile_find(self->tiles, lat, lon);
  41         if (!tile) return 0;
  42
  43         struct _TileData *data = tile->data;
  44         if (!data) return 0;
  45
  46         guint16 *bil  = data->bil;
  47         if (!bil)  return 0;
  48
  49         gint w = TILE_WIDTH;
  50         gint h = TILE_HEIGHT;
  51
  52         gdouble ymin  = tile->edge.s;
  53         gdouble ymax  = tile->edge.n;
  54         gdouble xmin  = tile->edge.w;
  55         gdouble xmax  = tile->edge.e;
  56
  57         gdouble xdist = xmax - xmin;
  58         gdouble ydist = ymax - ymin;
  59
  60         gdouble x =    (lon-xmin)/xdist  * w;
  61         gdouble y = (1-(lat-ymin)/ydist) * h;
  62
  63         gdouble x_rem = x - (int)x;
  64         gdouble y_rem = y - (int)y;
  65         guint x_flr = (int)x;
  66         guint y_flr = (int)y;
  67
  68         /* TODO: Fix interpolation at edges:
  69          *   - Pad these at the edges instead of wrapping/truncating
  70          *   - Figure out which pixels to index (is 0,0 edge, center, etc) */
  71         gint16 px00 = bil[MIN((y_flr  ),h-1)*w + MIN((x_flr  ),w-1)];
  72         gint16 px10 = bil[MIN((y_flr  ),h-1)*w + MIN((x_flr+1),w-1)];
  73         gint16 px01 = bil[MIN((y_flr+1),h-1)*w + MIN((x_flr  ),w-1)];
  74         gint16 px11 = bil[MIN((y_flr+1),h-1)*w + MIN((x_flr+1),w-1)];
  75
  76         gdouble elev =
  77                 px00 * (1-x_rem) * (1-y_rem) +
  78                 px10 * (  x_rem) * (1-y_rem) +
  79                 px01 * (1-x_rem) * (  y_rem) +
  80                 px11 * (  x_rem) * (  y_rem);
  81         return elev;
  82 }
  83
  84 /**********************
  85  * Loader and Freeers *
  86  **********************/
  87 #define LOAD_BIL    TRUE
  88 #define LOAD_OPENGL TRUE
  89 static guint16 *_load_bil(gchar *path)
  90 {
  91         gchar *data;
  92         g_file_get_contents(path, &data, NULL, NULL);
  93         g_debug("GisPluginSrtm: load_bil %p", data);
  94         return (guint16*)data;
  95 }
  96 static GdkPixbuf *_load_pixbuf(guint16 *bil)
  97 {
  98         GdkPixbuf *pixbuf = gdk_pixbuf_new(GDK_COLORSPACE_RGB, FALSE, 8, TILE_WIDTH, TILE_HEIGHT);
  99         guchar    *pixels = gdk_pixbuf_get_pixels(pixbuf);
 100         gint       stride = gdk_pixbuf_get_rowstride(pixbuf);
 101         gint       nchan  = gdk_pixbuf_get_n_channels(pixbuf);
 102
 103         for (int r = 0; r < TILE_HEIGHT; r++) {
 104                 for (int c = 0; c < TILE_WIDTH; c++) {
 105                         gint16 value = bil[r*TILE_WIDTH + c];
 106                         //guchar color = (float)(MAX(value,0))/8848 * 255;
 107                         guchar color = (float)value/8848 * 255;
 108                         pixels[r*stride + c*nchan + 0] = color;
 109                         pixels[r*stride + c*nchan + 1] = color;
 110                         pixels[r*stride + c*nchan + 2] = color;
 111                         if (nchan == 4)
 112                                 pixels[r*stride + c*nchan + 3] = 128;
 113                 }
 114         }
 115         g_debug("GisPluginSrtm: load_pixbuf %p", pixbuf);
 116         return pixbuf;
 117 }
 118 static guint _load_opengl(GdkPixbuf *pixbuf)
 119 {
 120         /* Load image */
 121         guchar *pixels = gdk_pixbuf_get_pixels(pixbuf);
 122         gint    alpha  = gdk_pixbuf_get_has_alpha(pixbuf);
 123         gint    nchan  = 4; // gdk_pixbuf_get_n_channels(pixbuf);
 124         gint    width  = gdk_pixbuf_get_width(pixbuf);
 125         gint    height = gdk_pixbuf_get_height(pixbuf);
 126
 127         /* Create Texture */
 128         guint opengl;
 129         glGenTextures(1, &opengl);
 130         glBindTexture(GL_TEXTURE_2D, opengl);
 131
 132         glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 133         glPixelStorei(GL_PACK_ALIGNMENT, 1);
 134         glTexImage2D(GL_TEXTURE_2D, 0, nchan, width, height, 0,
 135                         (alpha ? GL_RGBA : GL_RGB), GL_UNSIGNED_BYTE, pixels);
 136         glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 137         glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 138         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
 139         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
 140
 141         g_debug("GisPluginSrtm: load_opengl %d", opengl);
 142         return opengl;
 143 }
 144 static void _load_tile(GisTile *tile, gpointer _self)
 145 {
 146         GisPluginSrtm *self = _self;
 147         g_debug("GisPluginSrtm: _load_tile");
 148
 149         struct _TileData *data = g_new0(struct _TileData, 1);
 150         gchar *path = gis_wms_make_local(self->wms, tile);
 151         if (LOAD_BIL || LOAD_OPENGL)
 152                 data->bil = _load_bil(path);
 153         g_free(path);
 154         if (LOAD_OPENGL) {
 155                 GdkPixbuf *pixbuf = _load_pixbuf(data->bil);
 156                 data->opengl = _load_opengl(pixbuf);
 157                 g_object_unref(pixbuf);
 158         }
 159
 160         /* Do necessasairy processing */
 161         if (LOAD_BIL)
 162                 gis_opengl_set_height_func(self->opengl, tile,
 163                         _height_func, self, TRUE);
 164
 165         /* Cleanup unneeded things */
 166         if (!LOAD_BIL)
 167                 g_free(data->bil);
 168
 169         tile->data = data;
 170 }
 171
 172 static void _free_tile(GisTile *tile, gpointer _self)
 173 {
 174         GisPluginSrtm *self = _self;
 175         struct _TileData *data = tile->data;
 176         g_debug("GisPluginSrtm: _free_tile: %p=%d", data, data->opengl);
 177         if (LOAD_BIL)
 178                 g_free(data->bil);
 179         if (LOAD_OPENGL)
 180                 glDeleteTextures(1, &data->opengl);
 181         g_free(data);
 182 }
 183
 184 static gpointer _update_tiles(gpointer _self)
 185 {
 186         GisPluginSrtm *self = _self;
 187         gdouble lat, lon, elev;
 188         gis_view_get_location(self->view, &lat, &lon, &elev);
 189         gis_tile_update(self->tiles,
 190                         MAX_RESOLUTION, TILE_WIDTH, TILE_WIDTH,
 191                         lat, lon, elev,
 192                         _load_tile, self);
 193         gis_tile_gc(self->tiles, time(NULL)-10,
 194                         _free_tile, self);
 195         return NULL;
 196 }
 197
 198 /*************
 199  * Callbacks *
 200  *************/
 201 static void _on_location_changed(GisView *view, gdouble lat, gdouble lon, gdouble elev,
 202                 GisPluginSrtm *self)
 203 {
 204         _update_tiles(self);
 205 }
 206
 207 /***********
 208  * Methods *
 209  ***********/
 210 GisPluginSrtm *gis_plugin_srtm_new(GisWorld *world, GisView *view, GisOpenGL *opengl)
 211 {
 212         g_debug("GisPluginSrtm: new");
 213         GisPluginSrtm *self = g_object_new(GIS_TYPE_PLUGIN_SRTM, NULL);
 214         self->view   = view;
 215         self->opengl = opengl;
 216
 217         /* Load initial tiles */
 218         _load_tile(self->tiles, self);
 219         _update_tiles(self);
 220
 221         /* Connect signals */
 222         g_signal_connect(view, "location-changed", G_CALLBACK(_on_location_changed), self);
 223
 224         return self;
 225 }
 226
 227 static void gis_plugin_srtm_expose(GisPlugin *_self)
 228 {
 229         GisPluginSrtm *self = GIS_PLUGIN_SRTM(_self);
 230         g_debug("GisPluginSrtm: expose tiles=%p data=%p",
 231                 self->tiles, self->tiles->data);
 232         if (LOAD_OPENGL)
 233                 gis_opengl_render_tiles(self->opengl, self->tiles);
 234 }
 235
 236
 237 /****************
 238  * GObject code *
 239  ****************/
 240 /* Plugin init */
 241 static void gis_plugin_srtm_plugin_init(GisPluginInterface *iface);
 242 G_DEFINE_TYPE_WITH_CODE(GisPluginSrtm, gis_plugin_srtm, G_TYPE_OBJECT,
 243                 G_IMPLEMENT_INTERFACE(GIS_TYPE_PLUGIN,
 244                         gis_plugin_srtm_plugin_init));
 245 static void gis_plugin_srtm_plugin_init(GisPluginInterface *iface)
 246 {
 247         g_debug("GisPluginSrtm: plugin_init");
 248         /* Add methods to the interface */
 249         iface->expose = gis_plugin_srtm_expose;
 250 }
 251 /* Class/Object init */
 252 static void gis_plugin_srtm_init(GisPluginSrtm *self)
 253 {
 254         g_debug("GisPluginSrtm: init");
 255         /* Set defaults */
 256         self->tiles = gis_tile_new(NULL, NORTH, SOUTH, EAST, WEST);
 257         self->wms   = gis_wms_new(
 258                 "http://www.nasa.network.com/elev", "srtm30", "application/bil",
 259                 "srtm", ".bil", TILE_WIDTH, TILE_HEIGHT);
 260 }
 261 static void gis_plugin_srtm_dispose(GObject *gobject)
 262 {
 263         g_debug("GisPluginSrtm: dispose");
 264         GisPluginSrtm *self = GIS_PLUGIN_SRTM(gobject);
 265         /* Drop references */
 266         G_OBJECT_CLASS(gis_plugin_srtm_parent_class)->dispose(gobject);
 267 }
 268 static void gis_plugin_srtm_finalize(GObject *gobject)
 269 {
 270         g_debug("GisPluginSrtm: finalize");
 271         GisPluginSrtm *self = GIS_PLUGIN_SRTM(gobject);
 272         /* Free data */
 273         gis_tile_free(self->tiles, _free_tile, self);
 274         gis_wms_free(self->wms);
 275         G_OBJECT_CLASS(gis_plugin_srtm_parent_class)->finalize(gobject);
 276
 277 }
 278 static void gis_plugin_srtm_class_init(GisPluginSrtmClass *klass)
 279 {
 280         g_debug("GisPluginSrtm: class_init");
 281         GObjectClass *gobject_class = (GObjectClass*)klass;
 282         gobject_class->dispose  = gis_plugin_srtm_dispose;
 283         gobject_class->finalize = gis_plugin_srtm_finalize;
 284 }