void XShape::load(shapefileObj* shpfile, int i) {
msInitShape(&shape);
msSHPReadShape(shpfile->hSHP, i, &shape);
}
XShape::XShape(shapefileObj *shpfile, int i, int label_field)
:label(NULL)
{
#ifdef ENABLE_OPENGL
for (unsigned l=0; l < THINNING_LEVELS; l++)
index_count[l] = indices[l] = NULL;
#endif
shapeObj shape;
msInitShape(&shape);
msSHPReadShape(shpfile->hSHP, i, &shape);
bounds = GeoBounds(GeoPoint(Angle::Degrees(fixed(shape.bounds.minx)),
Angle::Degrees(fixed(shape.bounds.maxy))),
GeoPoint(Angle::Degrees(fixed(shape.bounds.maxx)),
Angle::Degrees(fixed(shape.bounds.miny))));
#ifdef ENABLE_OPENGL
center = bounds.GetCenter();
#endif
type = shape.type;
num_lines = 0;
const int min_points = min_points_for_type(shape.type);
if (min_points < 0) {
/* not supported, leave an empty XShape object */
points = NULL;
msFreeShape(&shape);
return;
}
const unsigned input_lines = std::min((unsigned)shape.numlines,
(unsigned)MAX_LINES);
unsigned num_points = 0;
for (unsigned l = 0; l < input_lines; ++l) {
if (shape.line[l].numpoints < min_points)
/* malformed shape */
continue;
lines[num_lines] = std::min(shape.line[l].numpoints, 16384);
num_points += lines[num_lines];
++num_lines;
}
#ifdef ENABLE_OPENGL
/* OpenGL:
* Convert all points of all lines to ShapePoints, using a projection
* that assumes the center of the screen is also the center of the shape.
* Resolution is set to 1m per pixel. This enables us to use a simple matrix
* multiplication to draw the shape.
* This approximation should work well with shapes of limited size
* (<< 400km). Perceivable distortion will only happen, when the latitude of
* the actual center of the screen is far away from the latitude of the
* center of the shape and the shape has a big vertical size.
*/
points = new ShapePoint[num_points];
ShapePoint *p = points;
#else // !ENABLE_OPENGL
/* convert all points of all lines to GeoPoints */
points = new GeoPoint[num_points];
GeoPoint *p = points;
#endif
for (unsigned l = 0; l < num_lines; ++l) {
const pointObj *src = shape.line[l].point;
num_points = lines[l];
for (unsigned j = 0; j < num_points; ++j, ++src)
#ifdef ENABLE_OPENGL
*p++ = geo_to_shape(GeoPoint(Angle::Degrees(fixed(src->x)),
Angle::Degrees(fixed(src->y))));
#else
*p++ = GeoPoint(Angle::Degrees(fixed(src->x)),
Angle::Degrees(fixed(src->y)));
#endif
}
if (label_field >= 0) {
const char *src = msDBFReadStringAttribute(shpfile->hDBF, i, label_field);
label = import_label(src);
}
msFreeShape(&shape);
}