]> Pileus Git - grits/blobdiff - src/gis/gis-opengl.c
Lots of work on libGIS
[grits] / src / gis / gis-opengl.c
index bdcaf404bf0c59da1ce6a96cb154c1dc3d757fc7..e1abb07d6dcf24b70aa9cf49a6762be0c895315c 100644 (file)
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+/* Tessellation, "finding intersecting triangles" */
+/* http://research.microsoft.com/pubs/70307/tr-2006-81.pdf */
+/* http://www.opengl.org/wiki/Alpha_Blending */
+
 #include <config.h>
 #include <math.h>
 #include <gdk/gdkkeysyms.h>
 #include <GL/glu.h>
 
 #include "gis-opengl.h"
+#include "roam.h"
+#include "wms.h"
 
-/****************
- * GObject code *
- ****************/
-G_DEFINE_TYPE(GisOpenGL, gis_opengl, G_TYPE_OBJECT);
-static void gis_opengl_init(GisOpenGL *self)
-{
-       g_debug("GisOpenGL: init");
-}
-static GObject *gis_opengl_constructor(GType gtype, guint n_properties,
-               GObjectConstructParam *properties)
+#define FOV_DIST   2000.0
+#define MPPX(dist) (4*dist/FOV_DIST)
+
+
+/*************
+ * ROAM Code *
+ *************/
+void roam_queue_draw(WmsCacheNode *node, gpointer _self)
 {
-       g_debug("GisOpengl: constructor");
-       GObjectClass *parent_class = G_OBJECT_CLASS(gis_opengl_parent_class);
-       return  parent_class->constructor(gtype, n_properties, properties);
+       gtk_widget_queue_draw(GTK_WIDGET(_self));
 }
-static void gis_opengl_dispose(GObject *gobject)
+
+void roam_height_func(RoamPoint *point, gpointer _self)
 {
-       g_debug("GisOpenGL: dispose");
-       GisOpenGL *self = GIS_OPENGL(gobject);
-       if (self->world) {
-               g_object_unref(self->world);
-               self->world = NULL;
+       GisOpenGL *self = _self;
+
+       gdouble cam_lle[3], cam_xyz[3];
+       gis_view_get_location(self->view, &cam_lle[0], &cam_lle[1], &cam_lle[2]);
+       lle2xyz(cam_lle[0], cam_lle[1], cam_lle[2], &cam_xyz[0], &cam_xyz[1], &cam_xyz[2]);
+
+       gdouble lat, lon, elev;
+       xyz2lle(point->x, point->y, point->z, &lat, &lon, &elev);
+
+       gdouble res = MPPX(distd(cam_xyz, (double*)point));
+       //g_message("lat=%f, lon=%f, res=%f", lat, lon, res);
+
+       WmsCacheNode *node = wms_info_fetch_cache(self->srtm, res, lat, lon, NULL, roam_queue_draw, self);
+
+       if (node) {
+               WmsBil *bil = node->data;
+
+               gint w = bil->width;
+               gint h = bil->height;
+
+               gdouble xmin  = node->latlon[0];
+               gdouble ymin  = node->latlon[1];
+               gdouble xmax  = node->latlon[2];
+               gdouble ymax  = node->latlon[3];
+
+               gdouble xdist = xmax - xmin;
+               gdouble ydist = ymax - ymin;
+
+               gdouble x =    (lon-xmin)/xdist  * w;
+               gdouble y = (1-(lat-ymin)/ydist) * h;
+
+               gdouble x_rem = x - (int)x;
+               gdouble y_rem = y - (int)y;
+               guint x_flr = (int)x;
+               guint y_flr = (int)y;
+
+               /* TODO: Fix interpolation at edges:
+                *   - Pad these at the edges instead of wrapping/truncating
+                *   - Figure out which pixels to index (is 0,0 edge, center, etc) */
+               gint16 px00 = bil->data[MIN((y_flr  ),h-1)*w + MIN((x_flr  ),w-1)];
+                gint16 px10 = bil->data[MIN((y_flr  ),h-1)*w + MIN((x_flr+1),w-1)];
+                gint16 px01 = bil->data[MIN((y_flr+1),h-1)*w + MIN((x_flr  ),w-1)];
+                gint16 px11 = bil->data[MIN((y_flr+1),h-1)*w + MIN((x_flr+1),w-1)];
+
+               elev =  px00 * (1-x_rem) * (1-y_rem) +
+                       px10 * (  x_rem) * (1-y_rem) +
+                       px01 * (1-x_rem) * (  y_rem) +
+                       px11 * (  x_rem) * (  y_rem);
+               //g_message("elev=%f -- %hd %hd %hd %hd",
+               //      elev, px00, px10, px01, px11);
+       } else {
+               elev = 0;
        }
-       if (self->view) {
-               g_object_unref(self->view);
-               self->view = NULL;
-       }
-       if (self->drawing) {
-               g_object_unref(self->drawing);
-               self->drawing = NULL;
-       }
-       G_OBJECT_CLASS(gis_opengl_parent_class)->dispose(gobject);
-}
-static void gis_opengl_finalize(GObject *gobject)
-{
-       g_debug("GisOpenGL: finalize");
-       G_OBJECT_CLASS(gis_opengl_parent_class)->finalize(gobject);
-       gtk_main_quit();
 
-}
-static void gis_opengl_class_init(GisOpenGLClass *klass)
-{
-       g_debug("GisOpenGL: class_init");
-       GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
-       gobject_class->constructor  = gis_opengl_constructor;
-       gobject_class->dispose      = gis_opengl_dispose;
-       gobject_class->finalize     = gis_opengl_finalize;
+       lle2xyz(lat, lon, elev, &point->x, &point->y, &point->z);
 }
 
-/*************
- * Callbacks *
- *************/
-gboolean on_button_press(GtkWidget *widget, GdkEventButton *event, GisOpenGL *self)
+void roam_tri_func(RoamTriangle *tri, gpointer _self)
 {
-       g_debug("GisOpenGL: on_drawing_button_press - Grabbing focus");
-       gtk_widget_grab_focus(GTK_WIDGET(self->drawing));
-       return TRUE;
+       GisOpenGL *self = _self;
+       if (tri->error < 0) return;
+
+       /* Get lat-lon min and maxes for the triangle */
+       gdouble lat[3], lon[3], elev[3];
+       xyz2lle(tri->p.r->x, tri->p.r->y, tri->p.r->z, &lat[0], &lon[0], &elev[0]);
+       xyz2lle(tri->p.m->x, tri->p.m->y, tri->p.m->z, &lat[1], &lon[1], &elev[1]);
+       xyz2lle(tri->p.l->x, tri->p.l->y, tri->p.l->z, &lat[2], &lon[2], &elev[2]);
+       gdouble lat_max = MAX(MAX(lat[0], lat[1]), lat[2]);
+       gdouble lat_min = MIN(MIN(lat[0], lat[1]), lat[2]);
+       gdouble lon_max = MAX(MAX(lon[0], lon[1]), lon[2]);
+       gdouble lon_min = MIN(MIN(lon[0], lon[1]), lon[2]);
+
+       /* Get target resolution */
+       gdouble cam_lle[3], cam_xyz[3];
+       gis_view_get_location(self->view, &cam_lle[0], &cam_lle[1], &cam_lle[2]);
+       lle2xyz(cam_lle[0], cam_lle[1], cam_lle[2], &cam_xyz[0], &cam_xyz[1], &cam_xyz[2]);
+       gdouble distr = distd(cam_xyz, (double*)tri->p.r);
+       gdouble distm = distd(cam_xyz, (double*)tri->p.m);
+       gdouble distl = distd(cam_xyz, (double*)tri->p.l);
+       double res = MPPX(MIN(MIN(distr, distm), distl));
+
+       /* TODO: 
+        *   - Fetch needed textures, not all corners
+        *   - Also fetch center textures that aren't touched by a corner
+        *   - Idea: send {lat,lon}{min,max} to fetch_cache and handle it in the recursion */
+       /* Fetch textures */
+       WmsCacheNode *textures[4] = {
+               wms_info_fetch_cache(self->bmng, res, lat_min, lon_min, NULL, roam_queue_draw, self),
+               wms_info_fetch_cache(self->bmng, res, lat_max, lon_min, NULL, roam_queue_draw, self),
+               wms_info_fetch_cache(self->bmng, res, lat_min, lon_max, NULL, roam_queue_draw, self),
+               wms_info_fetch_cache(self->bmng, res, lat_max, lon_max, NULL, roam_queue_draw, self),
+       };
+
+       /* Vertex color for hieght map viewing, 8848m == Everest */
+       gfloat colors[] = {
+               (elev[0]-EARTH_R)/8848,
+               (elev[1]-EARTH_R)/8848,
+               (elev[2]-EARTH_R)/8848,
+       };
+
+       /* Draw each texture */
+       /* TODO: Prevent double exposure when of hi-res textures on top of
+        * low-res textures when some high-res textures are not yet loaded. */
+       glBlendFunc(GL_ONE, GL_ZERO);
+       for (int i = 0; i < 4; i++) {
+               /* Skip missing textures */
+               if (textures[i] == NULL)
+                       continue;
+               /* Skip already drawn textures */
+               switch (i) {
+               case 3: if (textures[i] == textures[2]) continue;
+               case 2: if (textures[i] == textures[1]) continue;
+               case 1: if (textures[i] == textures[0]) continue;
+               }
+
+               WmsCacheNode *node = textures[i];
+
+               if (node->latlon[0] == -180) {
+                       if (lon[0] < -90 || lon[1] < -90 || lon[2] < -90) {
+                               if (lon[0] > 90) lon[0] -= 360;
+                               if (lon[1] > 90) lon[1] -= 360;
+                               if (lon[2] > 90) lon[2] -= 360;
+                       }
+               } else if (node->latlon[2] == 180.0) {
+                       if (lon[0] < -90) lon[0] += 360;
+                       if (lon[1] < -90) lon[1] += 360;
+                       if (lon[2] < -90) lon[2] += 360;
+               }
+
+               gdouble xmin  = node->latlon[0];
+               gdouble ymin  = node->latlon[1];
+               gdouble xmax  = node->latlon[2];
+               gdouble ymax  = node->latlon[3];
+
+               gdouble xdist = xmax - xmin;
+               gdouble ydist = ymax - ymin;
+
+               gdouble xy[][3] = {
+                       {(lon[0]-xmin)/xdist, 1-(lat[0]-ymin)/ydist},
+                       {(lon[1]-xmin)/xdist, 1-(lat[1]-ymin)/ydist},
+                       {(lon[2]-xmin)/xdist, 1-(lat[2]-ymin)/ydist},
+               };
+
+               glBindTexture(GL_TEXTURE_2D, *(guint*)node->data);
+
+               glBegin(GL_TRIANGLES);
+               glColor3fv(colors); glNormal3dv(tri->p.r->norm); glTexCoord2dv(xy[0]); glVertex3dv((double*)tri->p.r); 
+               glColor3fv(colors); glNormal3dv(tri->p.m->norm); glTexCoord2dv(xy[1]); glVertex3dv((double*)tri->p.m); 
+               glColor3fv(colors); glNormal3dv(tri->p.l->norm); glTexCoord2dv(xy[2]); glVertex3dv((double*)tri->p.l); 
+               glEnd();
+               glBlendFunc(GL_ONE, GL_ONE);
+       }
 }
-gboolean on_key_press(GtkWidget *widget, GdkEventKey *event, GisOpenGL *self)
+
+static void set_camera(GisOpenGL *self)
 {
-       g_debug("GisOpenGL: on_drawing_key_press - key=%x, state=%x, plus=%x",
-                       event->keyval, event->state, GDK_plus);
-       double x,y,z;
-       gis_view_get_location(self->view, &x, &y, &z);
-       guint kv = event->keyval;
-       if      (kv == GDK_Left  || kv == GDK_h) gis_view_pan(self->view, -z/10, 0, 0);
-       else if (kv == GDK_Down  || kv == GDK_j) gis_view_pan(self->view, 0, -z/10, 0);
-       else if (kv == GDK_Up    || kv == GDK_k) gis_view_pan(self->view, 0,  z/10, 0);
-       else if (kv == GDK_Right || kv == GDK_l) gis_view_pan(self->view,  z/10, 0, 0);
-       else if (kv == GDK_minus || kv == GDK_o) gis_view_zoom(self->view, 10./9);
-       else if (kv == GDK_plus  || kv == GDK_i) gis_view_zoom(self->view, 9./10);
-       else if (kv == GDK_H                   ) gis_view_rotate(self->view,  0, -10, 0);
-       else if (kv == GDK_J                   ) gis_view_rotate(self->view,  10,  0, 0);
-       else if (kv == GDK_K                   ) gis_view_rotate(self->view, -10,  0, 0);
-       else if (kv == GDK_L                   ) gis_view_rotate(self->view,  0,  10, 0);
-       return TRUE;
+       glMatrixMode(GL_MODELVIEW);
+       glLoadIdentity();
+       double lat, lon, elev, rx, ry, rz;
+       gis_view_get_location(self->view, &lat, &lon, &elev);
+       gis_view_get_rotation(self->view, &rx, &ry, &rz);
+       glRotatef(rx, 1, 0, 0);
+       glRotatef(rz, 0, 0, 1);
+       glTranslatef(0, 0, -elev2rad(elev));
+       glRotatef(lat, 1, 0, 0);
+       glRotatef(-lon, 0, 1, 0);
 }
 
-
-gboolean on_map(GtkWidget *drawing, GdkEventConfigure *event, GisOpenGL *self)
+static void set_visuals(GisOpenGL *self)
 {
-       g_debug("GisOpenGL: on_map");
+       /* Lighting */
+       glMatrixMode(GL_MODELVIEW);
+       glLoadIdentity();
+       float light_ambient[]  = {0.2f, 0.2f, 0.2f, 1.0f};
+       float light_diffuse[]  = {5.0f, 5.0f, 5.0f, 1.0f};
+       float light_position[] = {-13*EARTH_R, 1*EARTH_R, 3*EARTH_R, 1.0f};
+       glLightfv(GL_LIGHT0, GL_AMBIENT,  light_ambient);
+       glLightfv(GL_LIGHT0, GL_DIFFUSE,  light_diffuse);
+       glLightfv(GL_LIGHT0, GL_POSITION, light_position);
+       glEnable(GL_LIGHT0);
+       glEnable(GL_LIGHTING);
+
+       float material_ambient[]  = {0.2, 0.2, 0.2, 1.0};
+       float material_diffuse[]  = {0.8, 0.8, 0.8, 1.0};
+       float material_specular[] = {0.0, 0.0, 0.0, 1.0};
+       float material_emission[] = {0.0, 0.0, 0.0, 1.0};
+       glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT,  material_ambient);
+       glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE,  material_diffuse);
+       glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, material_specular);
+       glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, material_emission);
+       glDisable(GL_TEXTURE_2D);
+       glDisable(GL_COLOR_MATERIAL);
+
+       /* Camera */
+       set_camera(self);
 
        /* Misc */
-       glEnable(GL_BLEND);
+       gdouble lat, lon, elev;
+       gis_view_get_location(self->view, &lat, &lon, &elev);
+       gdouble rg   = MAX(0, 1-(elev/20000));
+       gdouble blue = MAX(0, 1-(elev/50000));
+       glClearColor(MIN(0.8,rg), MIN(0.8,rg), MIN(1,blue), 1.0f);
+
+       glDisable(GL_ALPHA_TEST);
+
        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
-       glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
+       glEnable(GL_BLEND);
 
-       /* Tessellation, "finding intersecting triangles" */
-       /* http://research.microsoft.com/pubs/70307/tr-2006-81.pdf */
-       /* http://www.opengl.org/wiki/Alpha_Blending */
-       glAlphaFunc(GL_GREATER,0.1);
-       glEnable(GL_ALPHA_TEST);
+       glCullFace(GL_BACK);
+       glEnable(GL_CULL_FACE);
 
-       /* Depth test */
        glClearDepth(1.0);
        glDepthFunc(GL_LEQUAL);
        glEnable(GL_DEPTH_TEST);
 
-       gis_opengl_end(self);
-       return FALSE;
+       glEnable(GL_LINE_SMOOTH);
+
+       glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
+       //glShadeModel(GL_FLAT);
 }
 
-gboolean on_configure(GtkWidget *drawing, GdkEventConfigure *event, GisOpenGL *self)
+
+/*************
+ * Callbacks *
+ *************/
+static void on_realize(GisOpenGL *self, gpointer _)
+{
+       set_visuals(self);
+}
+static gboolean on_configure(GisOpenGL *self, GdkEventConfigure *event, gpointer _)
 {
        g_debug("GisOpenGL: on_confiure");
        gis_opengl_begin(self);
 
-       double x, y, z;
-       gis_view_get_location(self->view, &x, &y, &z);
-
-       /* Window is at 500 m from camera */
-       double width  = GTK_WIDGET(self->drawing)->allocation.width;
-       double height = GTK_WIDGET(self->drawing)->allocation.height;
-
+       double width  = GTK_WIDGET(self)->allocation.width;
+       double height = GTK_WIDGET(self)->allocation.height;
        glViewport(0, 0, width, height);
 
-       /* Perspective */
        glMatrixMode(GL_PROJECTION);
        glLoadIdentity();
-       double ang = atan((height/2)/500);
+       double ang = atan(height/FOV_DIST);
+       gluPerspective(rad2deg(ang)*2, width/height, 1, 20*EARTH_R);
 
-       //gluPerspective(r2d(ang)*2, width/height, -z-20, -z+20);
-       gluPerspective(r2d(ang)*2, width/height, 1, 500*1000);
+       if (self->sphere)
+               roam_sphere_update_errors(self->sphere);
 
        gis_opengl_end(self);
        return FALSE;
 }
 
-gboolean on_expose(GtkWidget *drawing, GdkEventExpose *event, GisOpenGL *self)
+static void on_expose_plugin(GisPlugin *plugin, gchar *name, GisOpenGL *self)
+{
+       set_visuals(self);
+       glMatrixMode(GL_PROJECTION); glPushMatrix();
+       glMatrixMode(GL_MODELVIEW);  glPushMatrix();
+       gis_plugin_expose(plugin);
+       glMatrixMode(GL_PROJECTION); glPopMatrix();
+       glMatrixMode(GL_MODELVIEW);  glPopMatrix();
+}
+static gboolean on_expose(GisOpenGL *self, GdkEventExpose *event, gpointer _)
 {
        g_debug("GisOpenGL: on_expose - begin");
        gis_opengl_begin(self);
 
-       double lx, ly, lz;
-       double rx, ry, rz;
-       gis_view_get_location(self->view, &lx, &ly, &lz);
-       gis_view_get_rotation(self->view, &rx, &ry, &rz);
+       glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
-       glMatrixMode(GL_MODELVIEW);
-       glLoadIdentity();
-       glTranslatef(lx, ly, lz);
-       glRotatef(rx, 1, 0, 0);
-       glRotatef(ry, 0, 1, 0);
-       glRotatef(rz, 0, 0, 1);
+       set_visuals(self);
+       glEnable(GL_TEXTURE_2D);
+       roam_sphere_draw(self->sphere);
 
-       /* Expose plugins */
-       gis_plugins_foreach(self->plugins, G_CALLBACK(gis_plugin_expose), NULL);
+       //glDisable(GL_TEXTURE_2D);
+       //glEnable(GL_COLOR_MATERIAL);
+       //glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
+       //roam_sphere_draw(self->sphere);
 
+       //glColor4f(0.0, 0.0, 9.0, 0.6);
+       //glDisable(GL_TEXTURE_2D);
+       //glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
+       //roam_sphere_draw(self->sphere);
+
+       gis_plugins_foreach(self->plugins, G_CALLBACK(on_expose_plugin), self);
+
+       set_visuals(self);
        gis_opengl_end(self);
        gis_opengl_flush(self);
        g_debug("GisOpenGL: on_expose - end\n");
        return FALSE;
 }
 
-void on_state_changed(GisView *view,
-               gdouble x, gdouble y, gdouble z, GisOpenGL *self)
+static gboolean on_button_press(GisOpenGL *self, GdkEventButton *event, gpointer _)
 {
-       /* Reset clipping area and redraw */
-       on_configure(NULL, NULL, self);
+       g_debug("GisOpenGL: on_button_press - Grabbing focus");
+       gtk_widget_grab_focus(GTK_WIDGET(self));
+       return TRUE;
+}
+
+static gboolean on_key_press(GisOpenGL *self, GdkEventKey *event, gpointer _)
+{
+       g_debug("GisOpenGL: on_key_press - key=%x, state=%x, plus=%x",
+                       event->keyval, event->state, GDK_plus);
+
+       double lat, lon, elev, pan;
+       gis_view_get_location(self->view, &lat, &lon, &elev);
+       pan = MIN(elev/(EARTH_R/2), 30);
+       guint kv = event->keyval;
+       if      (kv == GDK_Left  || kv == GDK_h) gis_view_pan(self->view,  0,  -pan, 0);
+       else if (kv == GDK_Down  || kv == GDK_j) gis_view_pan(self->view, -pan, 0,   0);
+       else if (kv == GDK_Up    || kv == GDK_k) gis_view_pan(self->view,  pan, 0,   0);
+       else if (kv == GDK_Right || kv == GDK_l) gis_view_pan(self->view,  0,   pan, 0);
+       else if (kv == GDK_minus || kv == GDK_o) gis_view_zoom(self->view, 10./9);
+       else if (kv == GDK_plus  || kv == GDK_i) gis_view_zoom(self->view, 9./10);
+       else if (kv == GDK_H                   ) gis_view_rotate(self->view,  0,  0, -10);
+       else if (kv == GDK_J                   ) gis_view_rotate(self->view,  10, 0,  0);
+       else if (kv == GDK_K                   ) gis_view_rotate(self->view, -10, 0,  0);
+       else if (kv == GDK_L                   ) gis_view_rotate(self->view,  0,  0,  10);
+       return TRUE;
+}
+
+static void on_view_changed(GisView *view,
+               gdouble _1, gdouble _2, gdouble _3, GisOpenGL *self)
+{
+       gis_opengl_begin(self);
+       set_visuals(self);
+       roam_sphere_update_errors(self->sphere);
        gis_opengl_redraw(self);
+       gis_opengl_end(self);
+}
+
+static gboolean on_idle(GisOpenGL *self)
+{
+       gis_opengl_begin(self);
+       if (roam_sphere_split_merge(self->sphere))
+               gis_opengl_redraw(self);
+       gis_opengl_end(self);
+       return TRUE;
 }
 
+
 /***********
  * Methods *
  ***********/
-GisOpenGL *gis_opengl_new(GisWorld *world, GisView *view, GtkDrawingArea *drawing)
+GisOpenGL *gis_opengl_new(GisWorld *world, GisView *view, GisPlugins *plugins)
 {
        g_debug("GisOpenGL: new");
        GisOpenGL *self = g_object_new(GIS_TYPE_OPENGL, NULL);
        self->world   = world;
        self->view    = view;
-       self->drawing = drawing;
+       self->plugins = plugins;
        g_object_ref(world);
        g_object_ref(view);
-       g_object_ref(drawing);
 
-       /* OpenGL setup */
-       GdkGLConfig *glconfig = gdk_gl_config_new_by_mode(
-                       GDK_GL_MODE_RGBA   | GDK_GL_MODE_DEPTH |
-                       GDK_GL_MODE_DOUBLE | GDK_GL_MODE_ALPHA);
-       if (!glconfig)
-               g_error("Failed to create glconfig");
-       if (!gtk_widget_set_gl_capability(GTK_WIDGET(self->drawing),
-                               glconfig, NULL, TRUE, GDK_GL_RGBA_TYPE))
-               g_error("GL lacks required capabilities");
+       g_signal_connect(self->view, "location-changed", G_CALLBACK(on_view_changed), self);
+       g_signal_connect(self->view, "rotation-changed", G_CALLBACK(on_view_changed), self);
 
-       g_signal_connect(self->view, "location-changed", G_CALLBACK(on_state_changed), self);
-       g_signal_connect(self->view, "rotation-changed", G_CALLBACK(on_state_changed), self);
+       /* TODO: update point eights sometime later so we have heigh-res heights for them */
+       self->sphere = roam_sphere_new(roam_tri_func, roam_height_func, self);
 
-       g_signal_connect(self->drawing, "map-event",       G_CALLBACK(on_map),       self);
-       g_signal_connect(self->drawing, "configure-event", G_CALLBACK(on_configure), self);
-       g_signal_connect(self->drawing, "expose-event",    G_CALLBACK(on_expose),    self);
+       return g_object_ref(self);
+}
 
-       g_signal_connect(self->drawing, "button-press-event", G_CALLBACK(on_button_press), self);
-       g_signal_connect(self->drawing, "enter-notify-event", G_CALLBACK(on_button_press), self);
-       g_signal_connect(self->drawing, "key-press-event",    G_CALLBACK(on_key_press),    self);
-       return self;
+void gis_opengl_center_position(GisOpenGL *self, gdouble lat, gdouble lon, gdouble elev)
+{
+       set_camera(self);
+       glRotatef(lon, 0, 1, 0);
+       glRotatef(-lat, 1, 0, 0);
+       glTranslatef(0, 0, elev2rad(elev));
 }
 
 void gis_opengl_redraw(GisOpenGL *self)
 {
        g_debug("GisOpenGL: gl_redraw");
-       gtk_widget_queue_draw(GTK_WIDGET(self->drawing));
+       gtk_widget_queue_draw(GTK_WIDGET(self));
 }
 void gis_opengl_begin(GisOpenGL *self)
 {
        g_assert(GIS_IS_OPENGL(self));
 
-       GdkGLContext   *glcontext  = gtk_widget_get_gl_context(GTK_WIDGET(self->drawing));
-       GdkGLDrawable  *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(self->drawing));
+       GdkGLContext   *glcontext  = gtk_widget_get_gl_context(GTK_WIDGET(self));
+       GdkGLDrawable  *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(self));
 
        if (!gdk_gl_drawable_gl_begin(gldrawable, glcontext))
                g_assert_not_reached();
-
-       glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 }
 void gis_opengl_end(GisOpenGL *self)
 {
        g_assert(GIS_IS_OPENGL(self));
-       GdkGLDrawable *gldrawable = gdk_gl_drawable_get_current();
+       GdkGLDrawable *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(self));
        gdk_gl_drawable_gl_end(gldrawable);
 }
 void gis_opengl_flush(GisOpenGL *self)
 {
        g_assert(GIS_IS_OPENGL(self));
-       GdkGLDrawable *gldrawable = gdk_gl_drawable_get_current();
+       GdkGLDrawable *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(self));
        if (gdk_gl_drawable_is_double_buffered(gldrawable))
                gdk_gl_drawable_swap_buffers(gldrawable);
        else
                glFlush();
        gdk_gl_drawable_gl_end(gldrawable);
 }
+
+
+/****************
+ * GObject code *
+ ****************/
+G_DEFINE_TYPE(GisOpenGL, gis_opengl, GTK_TYPE_DRAWING_AREA);
+static void gis_opengl_init(GisOpenGL *self)
+{
+       g_debug("GisOpenGL: init");
+       self->bmng = wms_info_new_for_bmng(NULL, NULL);
+       self->srtm = wms_info_new_for_srtm(NULL, NULL);
+
+       /* OpenGL setup */
+       GdkGLConfig *glconfig = gdk_gl_config_new_by_mode(
+                       GDK_GL_MODE_RGBA   | GDK_GL_MODE_DEPTH |
+                       GDK_GL_MODE_DOUBLE | GDK_GL_MODE_ALPHA);
+       if (!glconfig)
+               g_error("Failed to create glconfig");
+       if (!gtk_widget_set_gl_capability(GTK_WIDGET(self),
+                               glconfig, NULL, TRUE, GDK_GL_RGBA_TYPE))
+               g_error("GL lacks required capabilities");
+       g_object_unref(glconfig);
+
+       gtk_widget_set_size_request(GTK_WIDGET(self), 600, 550);
+       gtk_widget_set_events(GTK_WIDGET(self),
+                       GDK_BUTTON_PRESS_MASK |
+                       GDK_ENTER_NOTIFY_MASK |
+                       GDK_KEY_PRESS_MASK);
+       g_object_set(self, "can-focus", TRUE, NULL);
+
+       self->sm_source = g_timeout_add(10, (GSourceFunc)on_idle, self);
+
+       g_signal_connect(self, "realize",            G_CALLBACK(on_realize),      NULL);
+       g_signal_connect(self, "configure-event",    G_CALLBACK(on_configure),    NULL);
+       g_signal_connect(self, "expose-event",       G_CALLBACK(on_expose),       NULL);
+
+       g_signal_connect(self, "button-press-event", G_CALLBACK(on_button_press), NULL);
+       g_signal_connect(self, "enter-notify-event", G_CALLBACK(on_button_press), NULL);
+       g_signal_connect(self, "key-press-event",    G_CALLBACK(on_key_press),    NULL);
+}
+static GObject *gis_opengl_constructor(GType gtype, guint n_properties,
+               GObjectConstructParam *properties)
+{
+       g_debug("GisOpengl: constructor");
+       GObjectClass *parent_class = G_OBJECT_CLASS(gis_opengl_parent_class);
+       return parent_class->constructor(gtype, n_properties, properties);
+}
+static void gis_opengl_dispose(GObject *_self)
+{
+       g_debug("GisOpenGL: dispose");
+       GisOpenGL *self = GIS_OPENGL(_self);
+       if (self->sm_source) {
+               g_source_remove(self->sm_source);
+               self->sm_source = 0;
+       }
+       if (self->sphere) {
+               roam_sphere_free(self->sphere);
+               self->sphere = NULL;
+       }
+       if (self->world) {
+               g_object_unref(self->world);
+               self->world = NULL;
+       }
+       if (self->view) {
+               g_object_unref(self->view);
+               self->view = NULL;
+       }
+       G_OBJECT_CLASS(gis_opengl_parent_class)->dispose(_self);
+}
+static void gis_opengl_finalize(GObject *_self)
+{
+       g_debug("GisOpenGL: finalize");
+       GisOpenGL *self = GIS_OPENGL(_self);
+       wms_info_free(self->bmng);
+       wms_info_free(self->srtm);
+       G_OBJECT_CLASS(gis_opengl_parent_class)->finalize(_self);
+}
+static void gis_opengl_class_init(GisOpenGLClass *klass)
+{
+       g_debug("GisOpenGL: class_init");
+       GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
+       gobject_class->constructor  = gis_opengl_constructor;
+       gobject_class->dispose      = gis_opengl_dispose;
+       gobject_class->finalize     = gis_opengl_finalize;
+}