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