// Create and return a new layer instance.
simplet_layer_t*
simplet_layer_new(const char *datastring){
simplet_layer_t *layer;
if(!(layer = malloc(sizeof(*layer))))
return NULL;
memset(layer, 0, sizeof(*layer));
layer->source = simplet_copy_string(datastring);
layer->error.status = SIMPLET_OK;
if(!(layer->filters = simplet_list_new())){
free(layer);
return NULL;
}
return layer;
}
// Create and return a new layer instance.
simplet_layer_t*
simplet_layer_new(const char *datastring){
simplet_layer_t *layer;
if(!(layer = malloc(sizeof(*layer))))
return NULL;
memset(layer, 0, sizeof(*layer));
layer->source = simplet_copy_string(datastring);
layer->status = SIMPLET_OK;
if(!(layer->queries = simplet_list_new())){
free(layer);
return NULL;
}
simplet_retain((simplet_retainable_t *)layer);
return layer;
}
// Create and add a placement to the current lithograph if it doesn't overlap
// with current labels.
void
simplet_lithograph_add_placement(simplet_lithograph_t *litho,
OGRFeatureH feature, simplet_list_t *styles, cairo_t *proj_ctx) {
simplet_style_t *field = simplet_lookup_style(styles, "text-field");
if(!field) return;
OGRFeatureDefnH defn;
if(!(defn = OGR_F_GetDefnRef(feature))) return;
int idx = OGR_FD_GetFieldIndex(defn, (const char*) field->arg);
if(idx < 0) return;
// Find the largest sub geometry of a particular multi-geometry.
OGRGeometryH super = OGR_F_GetGeometryRef(feature);
OGRGeometryH geom = super;
double area = 0.0;
switch(wkbFlatten(OGR_G_GetGeometryType(super))) {
case wkbMultiPolygon:
case wkbGeometryCollection:
for(int i = 0; i < OGR_G_GetGeometryCount(super); i++) {
OGRGeometryH subgeom = OGR_G_GetGeometryRef(super, i);
if(subgeom == NULL) continue;
double ar = OGR_G_Area(subgeom);
if(ar > area) {
geom = subgeom;
area = ar;
}
}
break;
default:
;
}
// Find the center of our geometry. This sometimes throws an invalid geometry
// error, so there is a slight bug here somehow.
OGRGeometryH center;
if(!(center = OGR_G_CreateGeometry(wkbPoint))) return;
if(OGR_G_Centroid(geom, center) == OGRERR_FAILURE) {
OGR_G_DestroyGeometry(center);
return;
}
// Turn font hinting off
cairo_font_options_t *opts;
if(!(opts = cairo_font_options_create())){
OGR_G_DestroyGeometry(center);
return;
}
cairo_font_options_set_hint_style(opts, CAIRO_HINT_STYLE_NONE);
cairo_font_options_set_hint_metrics(opts, CAIRO_HINT_METRICS_OFF);
pango_cairo_context_set_font_options(litho->pango_ctx, opts);
cairo_font_options_destroy(opts);
// Get the field containing the text for the label.
char *txt = simplet_copy_string(OGR_F_GetFieldAsString(feature, idx));
PangoLayout *layout = pango_layout_new(litho->pango_ctx);
pango_layout_set_text(layout, txt, -1);
free(txt);
// Grab the font to use and apply tracking.
simplet_style_t *font = simplet_lookup_style(styles, "font");
simplet_apply_styles(layout, styles, "letter-spacing", NULL);
const char *font_family;
if(!font)
font_family = "helvetica 12px";
else
font_family = font->arg;
PangoFontDescription *desc = pango_font_description_from_string(font_family);
pango_layout_set_font_description(layout, desc);
pango_font_description_free(desc);
double x = OGR_G_GetX(center, 0), y = OGR_G_GetY(center, 0);
cairo_user_to_device(proj_ctx, &x, &y);
// Finally try the placement and test for overlaps.
try_and_insert_placement(litho, layout, x, y);
OGR_G_DestroyGeometry(center);
}
// Set a copy of this source as this layers datasource string.
void
simplet_layer_set_source(simplet_layer_t *layer, char *source){
char *src = simplet_copy_string(source);
if(!src) set_error(layer, SIMPLET_OOM, "out of memory setting source");
layer->source = src;
}
// Get the datasource string for this layer.
void
simplet_layer_get_source(simplet_layer_t *layer, char **source){
*source = simplet_copy_string(layer->source);
}
