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Process large shapes much more efficiently by subdividing them first.

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curt 1999-05-13 02:38:34 +00:00
parent 202d1bb6e6
commit 8407c3f47b
1 changed files with 73 additions and 9 deletions
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82
Tools/Prep/ShapeFile/shape.cxx
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@ -175,7 +175,7 @@ void add_to_shape(int count, double *coords, gpc_polygon *shape) {
// process shape (write polygon to all intersecting tiles)
void process_shape(string path, AreaType area, gpc_polygon *gpc_shape) {
void process_shape(string path, AreaType area, gpc_polygon *master_gpc_shape) {
point2d min, max;
long int index;
int i, j;
@ -184,10 +184,10 @@ void process_shape(string path, AreaType area, gpc_polygon *gpc_shape) {
max.x = max.y = -200.0;
// find min/max of polygon
for ( i = 0; i < gpc_shape->num_contours; i++ ) {
for ( j = 0; j < gpc_shape->contour[i].num_vertices; j++ ) {
double x = gpc_shape->contour[i].vertex[j].x;
double y = gpc_shape->contour[i].vertex[j].y;
for ( i = 0; i < master_gpc_shape->num_contours; i++ ) {
for ( j = 0; j < master_gpc_shape->contour[i].num_vertices; j++ ) {
double x = master_gpc_shape->contour[i].vertex[j].x;
double y = master_gpc_shape->contour[i].vertex[j].y;
if ( x < min.x ) { min.x = x; }
if ( y < min.y ) { min.y = y; }
@ -198,7 +198,7 @@ void process_shape(string path, AreaType area, gpc_polygon *gpc_shape) {
/*
FILE *sfp= fopen("shape", "w");
gpc_write_polygon(sfp, gpc_shape);
gpc_write_polygon(sfp, master_gpc_shape);
fclose(sfp);
exit(-1);
*/
@ -218,7 +218,7 @@ void process_shape(string path, AreaType area, gpc_polygon *gpc_shape) {
FG_LOG( FG_GENERAL, FG_INFO, " Bucket max = " << b_max );
if ( b_min == b_max ) {
clip_and_write_poly( path, index, area, b_min, gpc_shape );
clip_and_write_poly( path, index, area, b_min, master_gpc_shape );
} else {
FGBucket b_cur;
int dx, dy, i, j;
@ -229,17 +229,81 @@ void process_shape(string path, AreaType area, gpc_polygon *gpc_shape) {
FG_LOG( FG_GENERAL, FG_INFO, " dx = " << dx
<< " dy = " << dy );
if ( (dx > 100) || (dy > 100) ) {
if ( (dx > 200) || (dy > 200) ) {
FG_LOG( FG_GENERAL, FG_ALERT,
"somethings really wrong!!!!" );
exit(-1);
}
for ( j = 0; j <= dy; j++ ) {
// for performance reasons, we'll clip out just this
// horizontal row, and clip all the tiles in this row
// against the smaller shape
FG_LOG ( FG_GENERAL, FG_INFO,
"Generating clip row " << j << " of " << dy );
FGBucket b_clip = fgBucketOffset(min.x, min.y, 0, j);
gpc_polygon row, clip_row;
point2d c, clip_max, clip_min;
c.x = b_clip.get_center_lon();
c.y = b_clip.get_center_lat();
// calculate bucket clip_min.y and clip_max.y
if ( (c.y >= -89.0) && (c.y < 89.0) ) {
clip_min.y = c.y - FG_HALF_BUCKET_SPAN;
clip_max.y = c.y + FG_HALF_BUCKET_SPAN;
} else if ( c.y < -89.0) {
clip_min.y = -90.0;
clip_max.y = -89.0;
} else if ( c.y >= 89.0) {
clip_min.y = 89.0;
clip_max.y = 90.0;
} else {
FG_LOG ( FG_GENERAL, FG_ALERT,
"Out of range latitude in clip_and_write_poly() = "
<< c.y );
}
clip_min.x = -180.0;
clip_max.x = 180.0;
// set up clipping tile
v_list.vertex[0].x = clip_min.x;
v_list.vertex[0].y = clip_min.y;
v_list.vertex[1].x = clip_max.x;
v_list.vertex[1].y = clip_min.y;
v_list.vertex[2].x = clip_max.x;
v_list.vertex[2].y = clip_max.y;
v_list.vertex[3].x = clip_min.x;
v_list.vertex[3].y = clip_max.y;
v_list.num_vertices = 4;
row.num_contours = 0;
row.contour = NULL;
gpc_add_contour( &row, &v_list, 0 );
clip_row.num_contours = 0;
clip_row.contour = NULL;
gpc_polygon_clip(GPC_INT, &row, master_gpc_shape, &clip_row);
/* FILE *sfp = fopen("master_shape", "w");
gpc_write_polygon(sfp, 0, master_gpc_shape);
fclose(sfp);
sfp = fopen("clip_row", "w");
gpc_write_polygon(sfp, 0, &clip_row);
fclose(sfp); */
for ( i = 0; i <= dx; i++ ) {
b_cur = fgBucketOffset(min.x, min.y, i, j);
clip_and_write_poly( path, index, area, b_cur, gpc_shape );
clip_and_write_poly( path, index, area, b_cur, &clip_row );
}
gpc_free_polygon(&row);
gpc_free_polygon(&clip_row);
}
// string answer; cin >> answer;
}