Pileus Git - grits/blob - src/objects/grits-marker.c

   1 /*
   2  * Copyright (C) 2009-2011 Andy Spencer <andy753421@gmail.com>
   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 /**
  19  * SECTION:grits-marker
  20  * @short_description: Single point markers
  21  *
  22  * Each #GritsMarker represents some point on the earth with some form of
  23  * content. Commonly this is used to mark geographic features such as cities or
  24  * states.
  25  *
  26  * While markers represent a place in three dimensions somewhere on, below, or
  27  * above the surface of the earth, they are drawn in 2 dimensions so that they
  28  * look normal and readable by the user. Due to this, GritsObjects should almost
  29  * always be added to the GRITS_LEVEL_OVERLAY level so they are drawn "above" the
  30  * actual earth.
  31  */
  32
  33 #include <config.h>
  34 #include <math.h>
  35 #include "gtkgl.h"
  36 #include "grits-marker.h"
  37
  38 /* Texture setup functions */
  39 static void render_point(GritsMarker *marker)
  40 {
  41         /* Draw outline */
  42         cairo_set_line_join(marker->cairo, CAIRO_LINE_JOIN_ROUND);
  43         cairo_set_line_width(marker->cairo, marker->outline*2);
  44         cairo_set_source_rgba(marker->cairo, 0, 0, 0, 1);
  45
  46         cairo_arc(marker->cairo, marker->xoff, marker->yoff, marker->radius,
  47                   0, 2*G_PI);
  48         cairo_stroke(marker->cairo);
  49
  50         /* Draw filler */
  51         cairo_set_source_rgba(marker->cairo, 1, 1, 1, 1);
  52
  53         cairo_arc(marker->cairo, marker->xoff, marker->yoff, marker->radius,
  54                   0, 2*G_PI);
  55         cairo_fill(marker->cairo);
  56 }
  57
  58 static void render_label(GritsMarker *marker)
  59 {
  60         g_assert(marker->label);
  61
  62         /* Draw outline */
  63         cairo_set_line_join(marker->cairo, CAIRO_LINE_JOIN_ROUND);
  64         cairo_set_line_width(marker->cairo, marker->outline*2);
  65         cairo_set_source_rgba(marker->cairo, 0, 0, 0, 1);
  66         cairo_select_font_face(marker->cairo, "sans-serif",
  67                         CAIRO_FONT_SLANT_NORMAL, CAIRO_FONT_WEIGHT_BOLD);
  68         cairo_set_font_size(marker->cairo, 13);
  69         cairo_move_to(marker->cairo, marker->xoff + (marker->icon_width  / 2),
  70                                      marker->yoff - (marker->icon_height / 2));
  71         cairo_text_path(marker->cairo, marker->label);
  72         cairo_stroke(marker->cairo);
  73
  74         /* Draw filler */
  75         cairo_set_source_rgba(marker->cairo, 1, 1, 1, 1);
  76         cairo_move_to(marker->cairo, marker->xoff + (marker->icon_width  / 2),
  77                                      marker->yoff - (marker->icon_height / 2));
  78         cairo_show_text(marker->cairo, marker->label);
  79 }
  80
  81 static void render_icon(GritsMarker *marker)
  82 {
  83         g_assert(marker->icon_img != NULL);
  84
  85         /* move to marker location */
  86         cairo_translate(marker->cairo, marker->xoff, marker->yoff);
  87
  88         /* center image */
  89         cairo_translate(marker->cairo, -marker->icon_width/2,
  90                                        -marker->icon_height/2);
  91
  92         cairo_set_source_surface(marker->cairo, marker->icon_img, 0, 0);
  93
  94         cairo_paint(marker->cairo);
  95 }
  96
  97 static void render_all(GritsMarker *marker)
  98 {
  99         g_assert(marker);
 100         if (marker->display_mask & GRITS_MARKER_DMASK_ICON)
 101                 render_icon(marker);
 102
 103         if (marker->display_mask & GRITS_MARKER_DMASK_POINT)
 104                 render_point(marker);
 105
 106         if (marker->display_mask & GRITS_MARKER_DMASK_LABEL)
 107                 render_label(marker);
 108
 109         /* Load GL texture */
 110         glEnable(GL_TEXTURE_2D);
 111         glGenTextures(1, &marker->tex);
 112         glBindTexture(GL_TEXTURE_2D, marker->tex);
 113         glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 114         glPixelStorei(GL_PACK_ALIGNMENT, 1);
 115         glTexImage2D(GL_TEXTURE_2D, 0, 4, marker->width, marker->height,
 116                 0, GL_BGRA, GL_UNSIGNED_BYTE,
 117                 cairo_image_surface_get_data(cairo_get_target(marker->cairo)));
 118         glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 119         glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 120 }
 121
 122
 123 /* Constructors */
 124 /**
 125  * grits_marker_new:
 126  * @label: a short description of the marker
 127  *
 128  * Create a new GritsMarker which shows the given label when drawn.
 129  *
 130  * Returns: the new #GritsMarker.
 131  */
 132 GritsMarker *grits_marker_new(const gchar *label)
 133 {
 134         GritsMarker *marker = g_object_new(GRITS_TYPE_MARKER, NULL);
 135
 136         GRITS_OBJECT(marker)->skip = GRITS_SKIP_CENTER;
 137
 138         marker->display_mask = GRITS_MARKER_DMASK_POINT |
 139                                GRITS_MARKER_DMASK_LABEL;
 140
 141         //g_debug("GritsMarker: new - %s", label);
 142         /* specify size of point and size of surface */
 143         marker->outline =   2;
 144         marker->radius  =   3;
 145         marker->width   = 128;
 146         marker->height  =  32;
 147         marker->icon_width  = marker->radius * 2;
 148         marker->icon_height = marker->radius * 3;
 149
 150         marker->xoff  = marker->radius+marker->outline;
 151         marker->yoff  = marker->height-(marker->radius+marker->outline);
 152         marker->cairo = cairo_create(cairo_image_surface_create(
 153                         CAIRO_FORMAT_ARGB32, marker->width, marker->height));
 154
 155         marker->label = g_strdup(label);
 156
 157         return marker;
 158 }
 159
 160 /**
 161  * grits_marker_icon_new:
 162  * @label:        The label to display if GRITS_MARKER_DMASK_LABEL is set
 163  * @filename:     The filename of the icon
 164  * @angle:        The angle to rotate the icon (0 is north)
 165  * @flip:         Whether to flip the image so that it's never upside down.
 166  *                Useful for non-symmetric icons which have an "up".
 167  * @display_mask: A bitmask which specifies which items to display.
 168  *
 169  * Create a new marker with a label, point, icon (png), or any
 170  * combination of the above.
 171  *
 172  * Returns: the new #GritsMarker
 173  */
 174 GritsMarker *grits_marker_icon_new(const gchar *label, const gchar *filename,
 175     guint angle, gboolean flip, guint display_mask)
 176 {
 177         GritsMarker *marker = g_object_new(GRITS_TYPE_MARKER, NULL);
 178
 179         marker->label = g_strdup(label);
 180         marker->angle = angle;
 181         marker->flip = flip;
 182         marker->display_mask = display_mask;
 183
 184         if (display_mask & GRITS_MARKER_DMASK_ICON) {
 185                 g_assert(filename != NULL);
 186                 g_debug("GritsMarker: marker_icon_new - marker image %s",
 187                         filename);
 188                 marker->icon_img = cairo_image_surface_create_from_png(filename);
 189                 if (cairo_surface_status(marker->icon_img)) {
 190                         g_warning("GritsMarker: marker_icon_new - "
 191                                   "error reading file %s", filename);
 192                         /* convert it to a point, better than nothing */
 193                         marker->display_mask &= ~GRITS_MARKER_DMASK_ICON;
 194                         marker->display_mask |=  GRITS_MARKER_DMASK_POINT;
 195                         marker->icon_width = 4;
 196                         marker->icon_height = 8;
 197
 198                 } else {
 199                         marker->icon_width =
 200                             cairo_image_surface_get_width(marker->icon_img);
 201                         marker->icon_height =
 202                             cairo_image_surface_get_height(marker->icon_img);
 203                 }
 204         } else {
 205                 marker->icon_img = NULL;
 206                 marker->icon_width = 4; /* room for the point if there is one */
 207                 marker->icon_height = 8;
 208         }
 209         g_debug("GritsMarker: marker_icon_new - width = %d, height = %d",
 210                 marker->icon_width, marker->icon_height);
 211
 212         marker->outline =   2;
 213         marker->radius  =   3;
 214
 215         /* this is the surface size, a guess really */
 216         marker->width   = marker->icon_width  + 128;
 217         marker->height  = marker->icon_height + 64;
 218
 219         marker->xoff  = marker->width/2;
 220         marker->yoff  = marker->height/2;
 221         marker->cairo = cairo_create(cairo_image_surface_create(
 222                         CAIRO_FORMAT_ARGB32, marker->width, marker->height));
 223
 224         /* clear the surface just in case */
 225         cairo_set_operator(marker->cairo, CAIRO_OPERATOR_SOURCE);
 226         //cairo_set_source_rgba(marker->cairo, 1.0, 0.0, 0.0, 0.3); // debug
 227         cairo_set_source_rgba(marker->cairo, 1.0, 0.0, 0.0, 0.0);
 228         cairo_paint(marker->cairo);
 229         cairo_set_operator(marker->cairo, CAIRO_OPERATOR_OVER);
 230
 231         render_all(marker);
 232
 233         if (marker->icon_img)
 234                 cairo_surface_destroy(marker->icon_img);
 235
 236         return marker;
 237 }
 238
 239
 240 /* Drawing */
 241 static void grits_marker_draw(GritsObject *_marker, GritsOpenGL *opengl)
 242 {
 243         GritsMarker *marker = GRITS_MARKER(_marker);
 244         GritsPoint  *point  = grits_object_center(marker);
 245
 246         cairo_surface_t *surface = cairo_get_target(marker->cairo);
 247         gdouble width  = cairo_image_surface_get_width(surface);
 248         gdouble height = cairo_image_surface_get_height(surface);
 249
 250         if (!marker->tex)
 251                 render_all(marker);
 252
 253         if (marker->ortho) {
 254                 gdouble px, py, pz;
 255                 grits_viewer_project(GRITS_VIEWER(opengl),
 256                                 point->lat, point->lon, point->elev,
 257                                 &px, &py, &pz);
 258
 259                 if (pz > 1)
 260                         return;
 261
 262                 GtkAllocation alloc;
 263                 gtk_widget_get_allocation(GTK_WIDGET(opengl), &alloc);
 264                 glTranslated(px, alloc.height-py, 0);
 265                 glRotatef(marker->angle, 0, 0, -1);
 266                 glTranslated(-marker->xoff, -marker->yoff, 0);
 267         } else {
 268                 gdouble scale, eye[3], pos[3] =
 269                         {point->lat, point->lon, point->elev};
 270                 grits_viewer_get_location(GRITS_VIEWER(opengl),
 271                        &eye[0], &eye[1], &eye[2]);
 272                 lle2xyz(eye[0],  eye[1],  eye[2],
 273                        &eye[0], &eye[1], &eye[2]);
 274                 lle2xyz(pos[0],  pos[1],  pos[2],
 275                        &pos[0], &pos[1], &pos[2]);
 276                 scale = MPPX(distd(eye, pos));
 277
 278                 glRotatef(marker->angle, 0, 0, -1);
 279                 glRotatef(180, 1, 0, 0);
 280                 glScalef(scale, scale, 1);
 281                 glTranslated(-marker->xoff, -marker->yoff, 0);
 282         }
 283
 284         //g_debug("GritsOpenGL: draw_marker - %s pz=%f ", marker->label, pz);
 285
 286         glDisable(GL_LIGHTING);
 287         glDisable(GL_COLOR_MATERIAL);
 288         glDisable(GL_DEPTH_TEST);
 289         glEnable(GL_TEXTURE_2D);
 290         glBindTexture(GL_TEXTURE_2D, marker->tex);
 291         glDisable(GL_CULL_FACE);
 292         glBegin(GL_QUADS);
 293         glTexCoord2f(1, 0); glVertex3f(width, 0     , 0); // 0 - 3    0
 294         glTexCoord2f(1, 1); glVertex3f(width, height, 0); // 1 - |    |
 295         glTexCoord2f(0, 1); glVertex3f(0    , height, 0); // 2 - |    |
 296         glTexCoord2f(0, 0); glVertex3f(0    , 0     , 0); // 3 - 2----1
 297         glEnd();
 298 }
 299
 300
 301 /* GObject code */
 302 G_DEFINE_TYPE(GritsMarker, grits_marker, GRITS_TYPE_OBJECT);
 303 static void grits_marker_init(GritsMarker *marker)
 304 {
 305         marker->ortho = TRUE;
 306 }
 307
 308 static void grits_marker_finalize(GObject *_marker)
 309 {
 310         //g_debug("GritsMarker: finalize - %s", marker->label);
 311         GritsMarker *marker = GRITS_MARKER(_marker);
 312         if (marker->tex)
 313                 glDeleteTextures(1, &marker->tex);
 314         if (marker->cairo) {
 315                 cairo_surface_t *surface = cairo_get_target(marker->cairo);
 316                 cairo_surface_destroy(surface);
 317                 cairo_destroy(marker->cairo);
 318         }
 319         g_free(marker->label);
 320 }
 321
 322 static void grits_marker_class_init(GritsMarkerClass *klass)
 323 {
 324         g_debug("GritsMarker: class_init");
 325         GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 326         gobject_class->finalize = grits_marker_finalize;
 327
 328         GritsObjectClass *object_class = GRITS_OBJECT_CLASS(klass);
 329         object_class->draw = grits_marker_draw;
 330 }