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         return marker;
 152 }
 153
 154 /**
 155  * grits_marker_icon_new:
 156  * @label:        The label to display if GRITS_MARKER_DMASK_LABEL is set
 157  * @filename:     The filename of the icon
 158  * @angle:        The angle to rotate the icon (0 is north)
 159  * @flip:         Whether to flip the image so that it's never upside down.
 160  *                Useful for non-symmetric icons which have an "up".
 161  * @display_mask: A bitmask which specifies which items to display.
 162  *
 163  * Create a new marker with a label, point, icon (png), or any
 164  * combination of the above.
 165  *
 166  * Returns: the new #GritsMarker
 167  */
 168 GritsMarker *grits_marker_icon_new(const gchar *label, const gchar *filename,
 169     guint angle, gboolean flip, guint display_mask)
 170 {
 171         GritsMarker *marker = g_object_new(GRITS_TYPE_MARKER, NULL);
 172
 173         marker->label = g_strdup(label);
 174         marker->angle = angle;
 175         marker->flip = flip;
 176         marker->display_mask = display_mask;
 177
 178         if (display_mask & GRITS_MARKER_DMASK_ICON) {
 179                 g_assert(filename != NULL);
 180                 g_debug("GritsMarker: marker_icon_new - marker image %s",
 181                         filename);
 182                 marker->icon_img = cairo_image_surface_create_from_png(filename);
 183                 if (cairo_surface_status(marker->icon_img)) {
 184                         g_warning("GritsMarker: marker_icon_new - "
 185                                   "error reading file %s", filename);
 186                         /* convert it to a point, better than nothing */
 187                         marker->display_mask &= ~GRITS_MARKER_DMASK_ICON;
 188                         marker->display_mask |=  GRITS_MARKER_DMASK_POINT;
 189                         marker->icon_width = 4;
 190                         marker->icon_height = 8;
 191
 192                 } else {
 193                         marker->icon_width =
 194                             cairo_image_surface_get_width(marker->icon_img);
 195                         marker->icon_height =
 196                             cairo_image_surface_get_height(marker->icon_img);
 197                 }
 198         } else {
 199                 marker->icon_img = NULL;
 200                 marker->icon_width = 4; /* room for the point if there is one */
 201                 marker->icon_height = 8;
 202         }
 203         g_debug("GritsMarker: marker_icon_new - width = %d, height = %d",
 204                 marker->icon_width, marker->icon_height);
 205
 206         marker->outline =   2;
 207         marker->radius  =   3;
 208
 209         /* this is the surface size, a guess really */
 210         marker->width   = marker->icon_width  + 128;
 211         marker->height  = marker->icon_height + 64;
 212
 213         marker->xoff  = marker->width/2;
 214         marker->yoff  = marker->height/2;
 215         marker->cairo = cairo_create(cairo_image_surface_create(
 216                         CAIRO_FORMAT_ARGB32, marker->width, marker->height));
 217
 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->tex)
 245                 render_all(marker);
 246
 247         if (marker->ortho) {
 248                 gdouble px, py, pz;
 249                 grits_viewer_project(GRITS_VIEWER(opengl),
 250                                 point->lat, point->lon, point->elev,
 251                                 &px, &py, &pz);
 252
 253                 gint win_width  = GTK_WIDGET(opengl)->allocation.width;
 254                 gint win_height = GTK_WIDGET(opengl)->allocation.height;
 255                 if (pz > 1)
 256                         return;
 257
 258                 glMatrixMode(GL_PROJECTION); glLoadIdentity();
 259                 glMatrixMode(GL_MODELVIEW);  glLoadIdentity();
 260                 glOrtho(0, win_width, win_height, 0, 1, -1);
 261                 glTranslated(px, win_height-py, 0);
 262                 glRotatef(marker->angle, 0, 0, -1);
 263                 glTranslated(-marker->xoff, -marker->yoff, 0);
 264         } else {
 265                 gdouble scale, eye[3], pos[3] =
 266                         {point->lat, point->lon, point->elev};
 267                 grits_viewer_get_location(GRITS_VIEWER(opengl),
 268                        &eye[0], &eye[1], &eye[2]);
 269                 lle2xyz(eye[0],  eye[1],  eye[2],
 270                        &eye[0], &eye[1], &eye[2]);
 271                 lle2xyz(pos[0],  pos[1],  pos[2],
 272                        &pos[0], &pos[1], &pos[2]);
 273                 scale = MPPX(distd(eye, pos));
 274
 275                 glRotatef(marker->angle, 0, 0, -1);
 276                 glRotatef(180, 1, 0, 0);
 277                 glScalef(scale, scale, 1);
 278                 glTranslated(-marker->xoff, -marker->yoff, 0);
 279         }
 280
 281         //g_debug("GritsOpenGL: draw_marker - %s pz=%f ", marker->label, pz);
 282
 283         glDisable(GL_LIGHTING);
 284         glDisable(GL_COLOR_MATERIAL);
 285         glDisable(GL_DEPTH_TEST);
 286         glEnable(GL_TEXTURE_2D);
 287         glBindTexture(GL_TEXTURE_2D, marker->tex);
 288         glDisable(GL_CULL_FACE);
 289         glBegin(GL_QUADS);
 290         glTexCoord2f(1, 0); glVertex3f(width, 0     , 0); // 0 - 3    0
 291         glTexCoord2f(1, 1); glVertex3f(width, height, 0); // 1 - |    |
 292         glTexCoord2f(0, 1); glVertex3f(0    , height, 0); // 2 - |    |
 293         glTexCoord2f(0, 0); glVertex3f(0    , 0     , 0); // 3 - 2----1
 294         glEnd();
 295 }
 296
 297
 298 /* GObject code */
 299 G_DEFINE_TYPE(GritsMarker, grits_marker, GRITS_TYPE_OBJECT);
 300 static void grits_marker_init(GritsMarker *marker)
 301 {
 302         marker->ortho = TRUE;
 303 }
 304
 305 static void grits_marker_finalize(GObject *_marker)
 306 {
 307         //g_debug("GritsMarker: finalize - %s", marker->label);
 308         GritsMarker *marker = GRITS_MARKER(_marker);
 309         if (marker->tex)
 310                 glDeleteTextures(1, &marker->tex);
 311         if (marker->cairo) {
 312                 cairo_surface_t *surface = cairo_get_target(marker->cairo);
 313                 cairo_surface_destroy(surface);
 314                 cairo_destroy(marker->cairo);
 315         }
 316         g_free(marker->label);
 317 }
 318
 319 static void grits_marker_class_init(GritsMarkerClass *klass)
 320 {
 321         g_debug("GritsMarker: class_init");
 322         GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 323         gobject_class->finalize = grits_marker_finalize;
 324
 325         GritsObjectClass *object_class = GRITS_OBJECT_CLASS(klass);
 326         object_class->draw = grits_marker_draw;
 327 }