2 * Copyright (C) 2009-2010 Andy Spencer <andy753421@gmail.com>
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.
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.
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/>.
20 * @short_description: Elevation plugin
22 * #GritsPluginElev provides access to ground elevation. It does this in two ways:
23 * First, it provides a height function used by the viewer when drawing the
24 * world. Second, it can load the elevation data into an image and draw a
25 * greyscale elevation overlay on the planets surface.
28 #include <glib/gstdio.h>
35 #define MAX_RESOLUTION 500
36 #define TILE_WIDTH 1024
37 #define TILE_HEIGHT 512
38 #define TILE_SIZE (TILE_WIDTH*TILE_HEIGHT*sizeof(guint16))
41 /* OpenGL has to be first to make grits_opengl_render_tiles happy */
46 static gdouble _height_func(gdouble lat, gdouble lon, gpointer _elev)
48 GritsPluginElev *elev = _elev;
51 GritsTile *tile = grits_tile_find(elev->tiles, lat, lon);
54 struct _TileData *data = tile->data;
57 guint16 *bil = data->bil;
63 gdouble ymin = tile->edge.s;
64 gdouble ymax = tile->edge.n;
65 gdouble xmin = tile->edge.w;
66 gdouble xmax = tile->edge.e;
68 gdouble xdist = xmax - xmin;
69 gdouble ydist = ymax - ymin;
71 gdouble x = (lon-xmin)/xdist * w;
72 gdouble y = (1-(lat-ymin)/ydist) * h;
74 gdouble x_rem = x - (int)x;
75 gdouble y_rem = y - (int)y;
79 //if (lon == 180 || lon == -180)
80 // g_message("lon=%f w=%d min=%f max=%f dist=%f x=%f rem=%f flr=%d",
81 // lon, w, xmin, xmax, xdist, x, x_rem, x_flr);
83 /* TODO: Fix interpolation at edges:
84 * - Pad these at the edges instead of wrapping/truncating
85 * - Figure out which pixels to index (is 0,0 edge, center, etc) */
86 gint16 px00 = bil[MIN((y_flr ),h-1)*w + MIN((x_flr ),w-1)];
87 gint16 px10 = bil[MIN((y_flr ),h-1)*w + MIN((x_flr+1),w-1)];
88 gint16 px01 = bil[MIN((y_flr+1),h-1)*w + MIN((x_flr ),w-1)];
89 gint16 px11 = bil[MIN((y_flr+1),h-1)*w + MIN((x_flr+1),w-1)];
91 return px00 * (1-x_rem) * (1-y_rem) +
92 px10 * ( x_rem) * (1-y_rem) +
93 px01 * (1-x_rem) * ( y_rem) +
94 px11 * ( x_rem) * ( y_rem);
97 /**********************
98 * Loader and Freeers *
99 **********************/
100 #define LOAD_BIL TRUE
101 #define LOAD_OPENGL FALSE
102 struct _LoadTileData {
103 GritsPluginElev *elev;
107 struct _TileData *data;
109 static guint16 *_load_bil(gchar *path)
113 g_file_get_contents(path, &data, &len, NULL);
114 g_debug("GritsPluginElev: load_bil %p", data);
115 if (len != TILE_SIZE) {
116 g_warning("GritsPluginElev: _load_bil - unexpected tile size %d, != %d",
121 return (guint16*)data;
123 static GdkPixbuf *_load_pixbuf(guint16 *bil)
125 GdkPixbuf *pixbuf = gdk_pixbuf_new(GDK_COLORSPACE_RGB, FALSE, 8, TILE_WIDTH, TILE_HEIGHT);
126 guchar *pixels = gdk_pixbuf_get_pixels(pixbuf);
127 gint stride = gdk_pixbuf_get_rowstride(pixbuf);
128 gint nchan = gdk_pixbuf_get_n_channels(pixbuf);
130 for (int r = 0; r < TILE_HEIGHT; r++) {
131 for (int c = 0; c < TILE_WIDTH; c++) {
132 gint16 value = bil[r*TILE_WIDTH + c];
133 //guchar color = (float)(MAX(value,0))/8848 * 255;
134 guchar color = (float)value/8848 * 255;
135 pixels[r*stride + c*nchan + 0] = color;
136 pixels[r*stride + c*nchan + 1] = color;
137 pixels[r*stride + c*nchan + 2] = color;
139 pixels[r*stride + c*nchan + 3] = 128;
142 g_debug("GritsPluginElev: load_pixbuf %p", pixbuf);
145 static guint _load_opengl(GdkPixbuf *pixbuf)
148 guchar *pixels = gdk_pixbuf_get_pixels(pixbuf);
149 gint alpha = gdk_pixbuf_get_has_alpha(pixbuf);
150 gint nchan = 4; // gdk_pixbuf_get_n_channels(pixbuf);
151 gint width = gdk_pixbuf_get_width(pixbuf);
152 gint height = gdk_pixbuf_get_height(pixbuf);
156 glGenTextures(1, &opengl);
157 glBindTexture(GL_TEXTURE_2D, opengl);
159 glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
160 glPixelStorei(GL_PACK_ALIGNMENT, 1);
161 glTexImage2D(GL_TEXTURE_2D, 0, nchan, width, height, 0,
162 (alpha ? GL_RGBA : GL_RGB), GL_UNSIGNED_BYTE, pixels);
163 glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
164 glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
165 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
166 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
168 g_debug("GritsPluginElev: load_opengl %d", opengl);
171 static gboolean _load_tile_cb(gpointer _load)
173 struct _LoadTileData *load = _load;
174 g_debug("GritsPluginElev: _load_tile_cb: %s", load->path);
175 GritsPluginElev *elev = load->elev;
176 GritsTile *tile = load->tile;
177 GdkPixbuf *pixbuf = load->pixbuf;
178 struct _TileData *data = load->data;
183 data->opengl = _load_opengl(pixbuf);
187 /* Do necessasairy processing */
188 /* TODO: Lock this and move to thread, can remove elev from _load then */
190 grits_viewer_set_height_func(elev->viewer, &tile->edge,
191 _height_func, elev, TRUE);
193 /* Cleanup unneeded things */
197 g_object_unref(pixbuf);
201 static void _load_tile(GritsTile *tile, gpointer _elev)
203 GritsPluginElev *elev = _elev;
205 struct _LoadTileData *load = g_new0(struct _LoadTileData, 1);
206 load->path = grits_wms_fetch(elev->wms, tile, GRITS_ONCE, NULL, NULL);
207 g_debug("GritsPluginElev: _load_tile: %s", load->path);
210 load->data = g_new0(struct _TileData, 1);
211 if (LOAD_BIL || LOAD_OPENGL) {
212 load->data->bil = _load_bil(load->path);
213 if (!load->data->bil) {
214 g_remove(load->path);
222 load->pixbuf = _load_pixbuf(load->data->bil);
225 g_idle_add_full(G_PRIORITY_LOW, _load_tile_cb, load, NULL);
228 static gboolean _free_tile_cb(gpointer _data)
230 struct _TileData *data = _data;
234 glDeleteTextures(1, &data->opengl);
238 static void _free_tile(GritsTile *tile, gpointer _elev)
240 g_debug("GritsPluginElev: _free_tile: %p", tile->data);
242 g_idle_add_full(G_PRIORITY_LOW, _free_tile_cb, tile->data, NULL);
245 static gpointer _update_tiles(gpointer _elev)
247 GritsPluginElev *elev = _elev;
248 if (!g_mutex_trylock(elev->mutex))
251 grits_viewer_get_location(elev->viewer, &eye.lat, &eye.lon, &eye.elev);
252 grits_tile_update(elev->tiles, &eye,
253 MAX_RESOLUTION, TILE_WIDTH, TILE_WIDTH,
255 grits_tile_gc(elev->tiles, time(NULL)-10,
257 g_mutex_unlock(elev->mutex);
264 static void _on_location_changed(GritsViewer *viewer,
265 gdouble lat, gdouble lon, gdouble elevation, GritsPluginElev *elev)
267 g_thread_create(_update_tiles, elev, FALSE, NULL);
270 static gpointer _threaded_init(GritsPluginElev *elev)
272 _load_tile(elev->tiles, elev);
281 * grits_plugin_elev_new:
282 * @viewer: the #GritsViewer to use for drawing
284 * Create a new instance of the elevation plugin.
286 * Returns: the new #GritsPluginElev
288 GritsPluginElev *grits_plugin_elev_new(GritsViewer *viewer)
290 g_debug("GritsPluginElev: new");
291 GritsPluginElev *elev = g_object_new(GRITS_TYPE_PLUGIN_ELEV, NULL);
292 elev->viewer = g_object_ref(viewer);
294 /* Load initial tiles */
295 g_thread_create((GThreadFunc)_threaded_init, elev, FALSE, NULL);
297 /* Connect signals */
298 elev->sigid = g_signal_connect(elev->viewer, "location-changed",
299 G_CALLBACK(_on_location_changed), elev);
303 grits_viewer_add(viewer, GRITS_OBJECT(elev->tiles), GRITS_LEVEL_WORLD, 0);
313 static void grits_plugin_elev_plugin_init(GritsPluginInterface *iface);
314 G_DEFINE_TYPE_WITH_CODE(GritsPluginElev, grits_plugin_elev, G_TYPE_OBJECT,
315 G_IMPLEMENT_INTERFACE(GRITS_TYPE_PLUGIN,
316 grits_plugin_elev_plugin_init));
317 static void grits_plugin_elev_plugin_init(GritsPluginInterface *iface)
319 g_debug("GritsPluginElev: plugin_init");
320 /* Add methods to the interface */
322 /* Class/Object init */
323 static void grits_plugin_elev_init(GritsPluginElev *elev)
325 g_debug("GritsPluginElev: init");
327 elev->mutex = g_mutex_new();
328 elev->tiles = grits_tile_new(NULL, NORTH, SOUTH, EAST, WEST);
329 elev->wms = grits_wms_new(
330 "http://www.nasa.network.com/elev", "srtm30", "application/bil",
331 "srtm/", "bil", TILE_WIDTH, TILE_HEIGHT);
333 static void grits_plugin_elev_dispose(GObject *gobject)
335 g_debug("GritsPluginElev: dispose");
336 GritsPluginElev *elev = GRITS_PLUGIN_ELEV(gobject);
337 /* Drop references */
340 grits_viewer_clear_height_func(elev->viewer);
342 grits_viewer_remove(elev->viewer, elev->tiles);
343 g_signal_handler_disconnect(elev->viewer, elev->sigid);
344 g_object_unref(elev->viewer);
347 G_OBJECT_CLASS(grits_plugin_elev_parent_class)->dispose(gobject);
349 static void grits_plugin_elev_finalize(GObject *gobject)
351 g_debug("GritsPluginElev: finalize");
352 GritsPluginElev *elev = GRITS_PLUGIN_ELEV(gobject);
354 grits_tile_free(elev->tiles, _free_tile, elev);
355 grits_wms_free(elev->wms);
356 g_mutex_lock(elev->mutex);
357 g_mutex_unlock(elev->mutex);
358 g_mutex_free(elev->mutex);
359 G_OBJECT_CLASS(grits_plugin_elev_parent_class)->finalize(gobject);
362 static void grits_plugin_elev_class_init(GritsPluginElevClass *klass)
364 g_debug("GritsPluginElev: class_init");
365 GObjectClass *gobject_class = (GObjectClass*)klass;
366 gobject_class->dispose = grits_plugin_elev_dispose;
367 gobject_class->finalize = grits_plugin_elev_finalize;