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tileset.c
1187 lines (1087 loc) · 47 KB
/
tileset.c
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/******************************************************************************
* $Id$
*
* Project: MapServer
* Purpose: MapCache tile caching support file: high level tile access
* Author: Thomas Bonfort and the MapServer team.
*
******************************************************************************
* Copyright (c) 1996-2011 Regents of the University of Minnesota.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies of this Software or works derived from this Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*****************************************************************************/
#include "mapcache.h"
#include <apr_strings.h>
#include <apr_file_info.h>
#include <apr_file_io.h>
#include <math.h>
#ifdef _WIN32
#include <limits.h>
#endif
char* mapcache_tileset_tile_resource_key(mapcache_context *ctx, mapcache_tile *tile) {
char *lockname = apr_psprintf(ctx->pool,
"%d-%d-%d-%s",
tile->z,tile->y/tile->tileset->metasize_y,tile->x/tile->tileset->metasize_x,
tile->tileset->name);
/* if the tileset has multiple grids, add the name of the current grid to the lock key*/
if(tile->tileset->grid_links->nelts > 1) {
lockname = apr_pstrcat(ctx->pool,lockname,tile->grid_link->grid->name,NULL);
}
if(tile->dimensions && tile->dimensions->nelts>0) {
int i;
for(i=0; i<tile->dimensions->nelts; i++) {
mapcache_requested_dimension *rdim = APR_ARRAY_IDX(tile->dimensions,i,mapcache_requested_dimension*);
char *dimvalue = apr_pstrdup(ctx->pool,rdim->cached_value);
char *iter = dimvalue;
while(*iter) {
if(*iter == '/') *iter='_';
iter++;
}
lockname = apr_pstrcat(ctx->pool,lockname,dimvalue,NULL);
}
}
return lockname;
}
char* mapcache_tileset_metatile_resource_key(mapcache_context *ctx, mapcache_metatile *mt)
{
return mapcache_tileset_tile_resource_key(ctx,&mt->tiles[0]);
}
void mapcache_tileset_configuration_check(mapcache_context *ctx, mapcache_tileset *tileset)
{
/* check we have all we want */
if(tileset->_cache == NULL) {
/* TODO: we should allow tilesets with no caches */
ctx->set_error(ctx, 400, "tileset \"%s\" has no cache configured.", tileset->name);
return;
}
if(apr_is_empty_array(tileset->grid_links)) {
ctx->set_error(ctx, 400, "tileset \"%s\" has no grids configured", tileset->name);
return;
}
#ifdef USE_PROJ
/* not implemented yet, will be used to automatically calculate wgs84bbox with proj */
else if(tileset->wgs84bbox[0]>=tileset->wgs84bbox[2]) {
mapcache_grid_link *sgrid = APR_ARRAY_IDX(tileset->grid_links,0,mapcache_grid_link*);
double *extent = sgrid->grid->extent;
if(sgrid->restricted_extent) {
extent = sgrid->restricted_extent;
}
}
#endif
if(!tileset->format && tileset->source && tileset->source->type == MAPCACHE_SOURCE_GDAL) {
ctx->set_error(ctx,400, "tileset \"%s\" references a gdal source. <format> tag is missing and mandatory in this case",
tileset->name);
return;
}
if(tileset->metabuffer < 0 || tileset->metasize_x < 1 || tileset->metasize_y < 1) {
ctx->set_error(ctx,400,"tileset \"%s\" has invalid metasize %d,%d or metabuffer %d",
tileset->name,tileset->metasize_x,tileset->metasize_y,tileset->metabuffer);
return;
}
if(!tileset->format && (
tileset->metasize_x != 1 ||
tileset->metasize_y != 1 ||
tileset->metabuffer != 0 ||
tileset->watermark)) {
if(tileset->watermark) {
ctx->set_error(ctx,400,"tileset \"%s\" has no <format> configured, but it is needed for the watermark",
tileset->name);
return;
} else {
ctx->set_error(ctx,400,"tileset \"%s\" has no <format> configured, but it is needed for metatiling",
tileset->name);
return;
}
}
if(tileset->format && tileset->format->type == GC_RAW) {
if(tileset->metasize_x != 1 || tileset->metasize_y != 1 || tileset->metabuffer != 0) {
ctx->set_error(ctx, 400, "tileset \"%s\" references a RAW format type, metatiling is not supported for the \"%s\" format", tileset->name, tileset->format->name);
}
}
}
void mapcache_tileset_add_watermark(mapcache_context *ctx, mapcache_tileset *tileset, const char *filename)
{
apr_file_t *f;
apr_finfo_t finfo;
int rv;
mapcache_buffer *watermarkdata;
apr_size_t size;
if(apr_file_open(&f, filename, APR_FOPEN_READ|APR_FOPEN_BUFFERED|APR_FOPEN_BINARY,
APR_OS_DEFAULT, ctx->pool) != APR_SUCCESS) {
ctx->set_error(ctx,500, "failed to open watermark image %s",filename);
return;
}
rv = apr_file_info_get(&finfo, APR_FINFO_SIZE, f);
if(rv != APR_SUCCESS || !finfo.size) {
ctx->set_error(ctx, 500, "watermark %s has no data",filename);
return;
}
watermarkdata = mapcache_buffer_create(finfo.size,ctx->pool);
//manually add the data to our buffer
size = finfo.size;
apr_file_read(f,watermarkdata->buf,&size);
watermarkdata->size = size;
if(size != finfo.size) {
ctx->set_error(ctx, 500, "failed to copy watermark image data, got %d of %d bytes",(int)size, (int)finfo.size);
return;
}
apr_file_close(f);
tileset->watermark = mapcache_imageio_decode(ctx,watermarkdata);
}
void mapcache_tileset_tile_validate_z(mapcache_context *ctx, mapcache_tile *tile) {
if(tile->z < tile->grid_link->minz || tile->z >= tile->grid_link->maxz) {
ctx->set_error(ctx,404,"invalid tile z level");
}
}
void mapcache_tileset_tile_validate_x(mapcache_context *ctx, mapcache_tile *tile) {
mapcache_extent_i limits;
limits = tile->grid_link->grid_limits[tile->z];
if(tile->x<limits.minx || tile->x>=limits.maxx) {
ctx->set_error(ctx, 404, "tile x=%d not in [%d,%d[",
tile->x,limits.minx,limits.maxx);
}
}
void mapcache_tileset_tile_validate_y(mapcache_context *ctx, mapcache_tile *tile) {
mapcache_extent_i limits;
limits = tile->grid_link->grid_limits[tile->z];
if(tile->y<limits.miny || tile->y>=limits.maxy) {
ctx->set_error(ctx, 404, "tile y=%d not in [%d,%d[",
tile->y,limits.miny,limits.maxy);
}
}
void mapcache_tileset_tile_validate(mapcache_context *ctx, mapcache_tile *tile)
{
mapcache_extent_i limits;
if(tile->z < tile->grid_link->minz || tile->z >= tile->grid_link->maxz) {
ctx->set_error(ctx,404,"invalid tile z level");
return;
}
limits = tile->grid_link->grid_limits[tile->z];
if(tile->x<limits.minx || tile->x>=limits.maxx) {
ctx->set_error(ctx, 404, "tile x=%d not in [%d,%d[",
tile->x,limits.minx,limits.maxx);
return;
}
if(tile->y<limits.miny || tile->y>=limits.maxy) {
ctx->set_error(ctx, 404, "tile y=%d not in [%d,%d[",
tile->y,limits.miny,limits.maxy);
return;
}
}
void mapcache_tileset_get_map_tiles(mapcache_context *ctx, mapcache_tileset *tileset,
mapcache_grid_link *grid_link,
mapcache_extent *bbox, int width, int height,
int *ntiles,
mapcache_tile ***tiles,
mapcache_grid_link **effectively_used_grid_link)
{
double resolution;
int level;
int bl_x,bl_y,tr_x,tr_y;
int mx,my,Mx,My;
int x,y;
int i=0;
resolution = mapcache_grid_get_resolution(bbox, width, height);
*effectively_used_grid_link = mapcache_grid_get_closest_wms_level(ctx,grid_link,resolution,&level);
/* we don't want to assemble tiles that have already been reassembled from a lower level */
if((*effectively_used_grid_link)->outofzoom_strategy == MAPCACHE_OUTOFZOOM_REASSEMBLE && level > (*effectively_used_grid_link)->max_cached_zoom) {
level = (*effectively_used_grid_link)->max_cached_zoom;
}
mapcache_grid_get_xy(ctx,(*effectively_used_grid_link)->grid,bbox->minx,bbox->miny,level,&bl_x,&bl_y);
mapcache_grid_get_xy(ctx,(*effectively_used_grid_link)->grid,bbox->maxx,bbox->maxy,level,&tr_x,&tr_y);
Mx = MAPCACHE_MAX(MAPCACHE_MIN(MAPCACHE_MAX(tr_x,bl_x),(*effectively_used_grid_link)->grid_limits[level].maxx),(*effectively_used_grid_link)->grid_limits[level].minx);
My = MAPCACHE_MAX(MAPCACHE_MIN(MAPCACHE_MAX(tr_y,bl_y),(*effectively_used_grid_link)->grid_limits[level].maxy),(*effectively_used_grid_link)->grid_limits[level].miny);
mx = MAPCACHE_MIN(MAPCACHE_MAX(MAPCACHE_MIN(tr_x,bl_x),(*effectively_used_grid_link)->grid_limits[level].minx),(*effectively_used_grid_link)->grid_limits[level].maxx);
my = MAPCACHE_MIN(MAPCACHE_MAX(MAPCACHE_MIN(tr_y,bl_y),(*effectively_used_grid_link)->grid_limits[level].miny),(*effectively_used_grid_link)->grid_limits[level].maxy);
*ntiles = (Mx-mx+1)*(My-my+1);
i=0;
*tiles = (mapcache_tile**)apr_pcalloc(ctx->pool, *ntiles*sizeof(mapcache_tile*));
for(x=mx; x<=Mx; x++) {
for(y=my; y<=My; y++) {
mapcache_tile *tile = mapcache_tileset_tile_create(ctx->pool,tileset, (*effectively_used_grid_link));
tile->x = x;
tile->y = y;
tile->z = level;
mapcache_tileset_tile_validate(ctx,tile);
if(GC_HAS_ERROR(ctx)) {
//clear the error message
ctx->clear_errors(ctx);
} else {
(*tiles)[i++]=tile;
}
}
}
*ntiles = i;
}
mapcache_image* mapcache_tileset_assemble_map_tiles(mapcache_context *ctx, mapcache_tileset *tileset,
mapcache_grid_link *grid_link,
mapcache_extent *bbox, int width, int height,
int ntiles,
mapcache_tile **tiles,
mapcache_resample_mode mode)
{
double hresolution = mapcache_grid_get_horizontal_resolution(bbox, width);
double vresolution = mapcache_grid_get_vertical_resolution(bbox, height);
mapcache_extent tilebbox;
mapcache_tile *toplefttile=NULL;
int mx=INT_MAX,my=INT_MAX,Mx=INT_MIN,My=INT_MIN;
int i;
mapcache_image *image;
mapcache_image *srcimage;
double tileresolution, dstminx, dstminy, hf, vf;
#ifdef DEBUG
/* we know at least one tile contains data */
for(i=0; i<ntiles; i++) {
if(!tiles[i]->nodata) {
break;
}
}
if(i==ntiles) {
ctx->set_error(ctx,500,"###BUG#### mapcache_tileset_assemble_map_tiles called with no tiles containing data");
return NULL;
}
#endif
image = mapcache_image_create_with_data(ctx,width,height);
if(ntiles == 0) {
image->has_alpha = MC_ALPHA_YES;
image->is_blank = MC_EMPTY_YES;
return image;
}
/* compute the number of tiles horizontally and vertically */
for(i=0; i<ntiles; i++) {
mapcache_tile *tile = tiles[i];
if(tile->x < mx) mx = tile->x;
if(tile->y < my) my = tile->y;
if(tile->x > Mx) Mx = tile->x;
if(tile->y > My) My = tile->y;
}
/* create image that will contain the unscaled tiles data */
srcimage = mapcache_image_create_with_data(ctx,
(Mx-mx+1)*tiles[0]->grid_link->grid->tile_sx,
(My-my+1)*tiles[0]->grid_link->grid->tile_sy);
/* copy the tiles data into the src image */
for(i=0; i<ntiles; i++) {
int ox,oy; /* the offset from the start of the src image to the start of the tile */
mapcache_image fakeimg;
mapcache_tile *tile = tiles[i];
switch(grid_link->grid->origin) {
case MAPCACHE_GRID_ORIGIN_BOTTOM_LEFT:
if(tile->x == mx && tile->y == My) {
toplefttile = tile;
}
ox = (tile->x - mx) * tile->grid_link->grid->tile_sx;
oy = (My - tile->y) * tile->grid_link->grid->tile_sy;
break;
case MAPCACHE_GRID_ORIGIN_TOP_LEFT:
if(tile->x == mx && tile->y == my) {
toplefttile = tile;
}
ox = (tile->x - mx) * tile->grid_link->grid->tile_sx;
oy = (tile->y - my) * tile->grid_link->grid->tile_sy;
break;
case MAPCACHE_GRID_ORIGIN_BOTTOM_RIGHT:
if(tile->x == Mx && tile->y == My) {
toplefttile = tile;
}
ox = (Mx - tile->x) * tile->grid_link->grid->tile_sx;
oy = (My - tile->y) * tile->grid_link->grid->tile_sy;
break;
case MAPCACHE_GRID_ORIGIN_TOP_RIGHT:
if(tile->x == Mx && tile->y == my) {
toplefttile = tile;
}
ox = (Mx - tile->x) * tile->grid_link->grid->tile_sx;
oy = (tile->y - my) * tile->grid_link->grid->tile_sy;
break;
default:
ctx->set_error(ctx,500,"BUG: invalid grid origin");
return NULL;
}
if(tile->nodata) continue;
fakeimg.stride = srcimage->stride;
fakeimg.data = &(srcimage->data[oy*srcimage->stride+ox*4]);
if(!tile->raw_image) {
mapcache_imageio_decode_to_image(ctx,tile->encoded_data,&fakeimg);
} else {
int r;
unsigned char *srcptr = tile->raw_image->data;
unsigned char *dstptr = fakeimg.data;
for(r=0; r<tile->raw_image->h; r++) {
memcpy(dstptr,srcptr,tile->raw_image->stride);
srcptr += tile->raw_image->stride;
dstptr += fakeimg.stride;
}
}
}
assert(toplefttile);
/* copy/scale the srcimage onto the destination image */
tileresolution = toplefttile->grid_link->grid->levels[toplefttile->z]->resolution;
mapcache_grid_get_tile_extent(ctx,toplefttile->grid_link->grid,
toplefttile->x, toplefttile->y, toplefttile->z, &tilebbox);
/*compute the pixel position of top left corner*/
dstminx = (tilebbox.minx-bbox->minx)/hresolution;
dstminy = (bbox->maxy-tilebbox.maxy)/vresolution;
hf = tileresolution/hresolution;
vf = tileresolution/vresolution;
if(fabs(hf-1)<0.0001 && fabs(vf-1)<0.0001) {
//use nearest resampling if we are at the resolution of the tiles
mapcache_image_copy_resampled_nearest(ctx,srcimage,image,dstminx,dstminy,hf,vf);
} else {
switch(mode) {
case MAPCACHE_RESAMPLE_BILINEAR:
mapcache_image_copy_resampled_bilinear(ctx,srcimage,image,dstminx,dstminy,hf,vf,0);
break;
default:
mapcache_image_copy_resampled_nearest(ctx,srcimage,image,dstminx,dstminy,hf,vf);
break;
}
}
/* free the memory of the temporary source image */
apr_pool_cleanup_run(ctx->pool, srcimage->data, (void*)free) ;
return image;
}
/*
* compute the metatile that should be rendered for the given tile
*/
mapcache_metatile* mapcache_tileset_metatile_get(mapcache_context *ctx, mapcache_tile *tile)
{
mapcache_metatile *mt = (mapcache_metatile*)apr_pcalloc(ctx->pool, sizeof(mapcache_metatile));
int i,j,blx,bly;
mapcache_tileset *tileset = tile->tileset;
mapcache_grid *grid = tile->grid_link->grid;
double res = grid->levels[tile->z]->resolution;
double gbuffer,gwidth,gheight,fullgwidth,fullgheight;
mt->map.tileset = tileset;
mt->map.grid_link = tile->grid_link;
mt->z = tile->z;
mt->x = tile->x / tileset->metasize_x;
if(tile->x < 0)
mt->x --;
mt->y = tile->y / tileset->metasize_y;
if(tile->y < 0)
mt->y --;
blx = mt->x * tileset->metasize_x;
bly = mt->y * tileset->metasize_y;
/* adjust the size of the the metatile so it does not extend past the grid limits.
* If we don't do this, we end up with cut labels on the edges of the tile grid
*/
if(blx+tileset->metasize_x-1 >= grid->levels[tile->z]->maxx) {
mt->metasize_x = grid->levels[tile->z]->maxx - blx;
} else {
mt->metasize_x = tileset->metasize_x;
}
if(bly+tileset->metasize_y-1 >= grid->levels[tile->z]->maxy) {
mt->metasize_y = grid->levels[tile->z]->maxy - bly;
} else {
mt->metasize_y = tileset->metasize_y;
}
mt->ntiles = mt->metasize_x * mt->metasize_y;
mt->tiles = (mapcache_tile*)apr_pcalloc(ctx->pool, mt->ntiles * sizeof(mapcache_tile));
mt->map.width = mt->metasize_x * grid->tile_sx + 2 * tileset->metabuffer;
mt->map.height = mt->metasize_y * grid->tile_sy + 2 * tileset->metabuffer;
mt->map.dimensions = tile->dimensions;
/* buffer in geographical units */
gbuffer = res * tileset->metabuffer;
/* adjusted metatile size in geographical units */
gwidth = res * mt->metasize_x * grid->tile_sx;
gheight = res * mt->metasize_y * grid->tile_sy;
/* configured metatile size in geographical units */
fullgwidth = res * tileset->metasize_x * grid->tile_sx;
fullgheight = res * tileset->metasize_y * grid->tile_sy;
switch(grid->origin) {
case MAPCACHE_GRID_ORIGIN_BOTTOM_LEFT:
mt->map.extent.minx = grid->extent.minx + mt->x * fullgwidth - gbuffer;
mt->map.extent.miny = grid->extent.miny + mt->y * fullgheight - gbuffer;
mt->map.extent.maxx = mt->map.extent.minx + gwidth + 2 * gbuffer;
mt->map.extent.maxy = mt->map.extent.miny + gheight + 2 * gbuffer;
break;
case MAPCACHE_GRID_ORIGIN_TOP_LEFT:
mt->map.extent.minx = grid->extent.minx + mt->x * fullgwidth - gbuffer;
mt->map.extent.maxy = grid->extent.maxy - mt->y * fullgheight + gbuffer;
mt->map.extent.maxx = mt->map.extent.minx + gwidth + 2 * gbuffer;
mt->map.extent.miny = mt->map.extent.maxy - gheight - 2 * gbuffer;
break;
case MAPCACHE_GRID_ORIGIN_BOTTOM_RIGHT:
case MAPCACHE_GRID_ORIGIN_TOP_RIGHT:
ctx->set_error(ctx,500,"origin not implemented");
return NULL;
}
for(i=0; i<mt->metasize_x; i++) {
for(j=0; j<mt->metasize_y; j++) {
mapcache_tile *t = &(mt->tiles[i*mt->metasize_y+j]);
t->dimensions = tile->dimensions;
t->grid_link = tile->grid_link;
t->z = tile->z;
t->x = blx + i;
t->y = bly + j;
t->tileset = tile->tileset;
}
}
return mt;
}
/*
* do the actual rendering and saving of a metatile:
* - query the datasource for the image data
* - split the resulting image along the metabuffer / metatiles
* - save each tile to cache
*/
void mapcache_tileset_render_metatile(mapcache_context *ctx, mapcache_metatile *mt)
{
mapcache_tileset *tileset = mt->map.tileset;
if(!tileset->source || tileset->read_only) {
ctx->set_error(ctx,500,"tileset_render_metatile called on tileset with no source or that is read-only");
return;
}
mapcache_source_render_map(ctx, tileset->source, &mt->map);
GC_CHECK_ERROR(ctx);
mapcache_image_metatile_split(ctx, mt);
GC_CHECK_ERROR(ctx);
mapcache_cache_tile_multi_set(ctx, tileset->_cache, mt->tiles, mt->ntiles);
}
/*
* allocate and initialize a new tileset
*/
mapcache_tileset* mapcache_tileset_create(mapcache_context *ctx)
{
mapcache_tileset* tileset = (mapcache_tileset*)apr_pcalloc(ctx->pool, sizeof(mapcache_tileset));
tileset->metasize_x = tileset->metasize_y = 1;
tileset->metabuffer = 0;
tileset->expires = 300; /*set a reasonable default to 5 mins */
tileset->auto_expire = 0;
tileset->read_only = 0;
tileset->metadata = apr_table_make(ctx->pool,3);
tileset->dimensions = NULL;
tileset->format = NULL;
tileset->grid_links = NULL;
tileset->config = NULL;
tileset->store_dimension_assemblies = 1;
tileset->dimension_assembly_type = MAPCACHE_DIMENSION_ASSEMBLY_NONE;
tileset->subdimension_read_only = 0;
return tileset;
}
mapcache_tileset* mapcache_tileset_clone(mapcache_context *ctx, mapcache_tileset *src)
{
mapcache_tileset* dst = (mapcache_tileset*)apr_pcalloc(ctx->pool, sizeof(mapcache_tileset));
dst->metasize_x = src->metasize_x;
dst->metasize_y = src->metasize_y;
dst->metabuffer = src->metabuffer;
dst->expires = src->expires;
dst->auto_expire = src->auto_expire;
dst->metadata = src->metadata;
dst->dimensions = src->dimensions;
dst->format = src->format;
dst->grid_links = src->grid_links;
dst->config = src->config;
dst->name = src->name;
dst->_cache = src->_cache;
dst->source = src->source;
dst->watermark = src->watermark;
dst->wgs84bbox = src->wgs84bbox;
dst->format = src->format;
dst->store_dimension_assemblies = src->store_dimension_assemblies;
dst->dimension_assembly_type = src->dimension_assembly_type;
dst->subdimension_read_only = src->subdimension_read_only;
return dst;
}
/*
* allocate and initialize a tile for a given tileset
*/
mapcache_tile* mapcache_tileset_tile_create(apr_pool_t *pool, mapcache_tileset *tileset, mapcache_grid_link *grid_link)
{
mapcache_tile *tile = (mapcache_tile*)apr_pcalloc(pool, sizeof(mapcache_tile));
tile->tileset = tileset;
if(tileset->auto_expire) {
tile->expires = tileset->auto_expire;
} else {
tile->expires = tileset->expires;
}
tile->grid_link = grid_link;
if(tileset->dimensions) {
int i;
tile->dimensions = apr_array_make(pool,tileset->dimensions->nelts,sizeof(mapcache_requested_dimension*));
for(i=0; i<tileset->dimensions->nelts; i++) {
mapcache_dimension *dimension = APR_ARRAY_IDX(tileset->dimensions,i,mapcache_dimension*);
mapcache_requested_dimension *rdim = apr_pcalloc(pool,sizeof(mapcache_requested_dimension));
rdim->requested_value = dimension->default_value;
rdim->cached_value = NULL;
rdim->dimension = dimension;
APR_ARRAY_PUSH(tile->dimensions,mapcache_requested_dimension*) = rdim;
}
}
return tile;
}
mapcache_tile* mapcache_tileset_tile_clone(apr_pool_t *pool, mapcache_tile *src)
{
mapcache_tile *tile = (mapcache_tile*)apr_pcalloc(pool, sizeof(mapcache_tile));
tile->tileset = src->tileset;
tile->expires = src->expires;
tile->grid_link = src->grid_link;
tile->dimensions = mapcache_requested_dimensions_clone(pool, src->dimensions);
tile->x = src->x;
tile->y = src->y;
tile->z = src->z;
tile->allow_redirect = src->allow_redirect;
return tile;
}
mapcache_map* mapcache_tileset_map_clone(apr_pool_t *pool, mapcache_map *src)
{
mapcache_map *map = (mapcache_map*)apr_pcalloc(pool, sizeof(mapcache_map));
map->tileset = src->tileset;
map->expires = src->expires;
map->grid_link = src->grid_link;
map->dimensions = mapcache_requested_dimensions_clone(pool, src->dimensions);
map->height = src->height;
map->width = src->width;
map->extent = src->extent;
return map;
}
/*
* allocate and initialize a map for a given tileset
*/
mapcache_map* mapcache_tileset_map_create(apr_pool_t *pool, mapcache_tileset *tileset, mapcache_grid_link *grid_link)
{
mapcache_map *map = (mapcache_map*)apr_pcalloc(pool, sizeof(mapcache_map));
map->tileset = tileset;
map->grid_link = grid_link;
if(tileset->dimensions) {
int i;
map->dimensions = apr_array_make(pool,tileset->dimensions->nelts,sizeof(mapcache_requested_dimension*));
for(i=0; i<tileset->dimensions->nelts; i++) {
mapcache_dimension *dimension = APR_ARRAY_IDX(tileset->dimensions,i,mapcache_dimension*);
mapcache_requested_dimension *rdim = apr_pcalloc(pool,sizeof(mapcache_requested_dimension));
rdim->requested_value = dimension->default_value;
rdim->cached_value = NULL;
rdim->dimension = dimension;
APR_ARRAY_PUSH(map->dimensions,mapcache_requested_dimension*) = rdim;
}
}
return map;
}
/*
* allocate and initialize a feature_info for a given tileset
*/
mapcache_feature_info* mapcache_tileset_feature_info_create(apr_pool_t *pool, mapcache_tileset *tileset,
mapcache_grid_link *grid_link)
{
mapcache_feature_info *fi = (mapcache_feature_info*)apr_pcalloc(pool, sizeof(mapcache_feature_info));
fi->map.tileset = tileset;
fi->map.grid_link = grid_link;
if(tileset->dimensions) {
int i;
fi->map.dimensions = apr_array_make(pool,tileset->dimensions->nelts,sizeof(mapcache_requested_dimension*));
for(i=0; i<tileset->dimensions->nelts; i++) {
mapcache_dimension *dimension = APR_ARRAY_IDX(tileset->dimensions,i,mapcache_dimension*);
mapcache_requested_dimension *rdim = apr_pcalloc(pool,sizeof(mapcache_requested_dimension));
rdim->requested_value = dimension->default_value;
rdim->cached_value = NULL;
rdim->dimension = dimension;
APR_ARRAY_PUSH(fi->map.dimensions,mapcache_requested_dimension*) = rdim;
}
}
return fi;
}
void mapcache_tileset_assemble_out_of_zoom_tile(mapcache_context *ctx, mapcache_tile *tile) {
mapcache_extent tile_bbox;
double shrink_x, shrink_y, scalefactor;
int x[4],y[4];
int i, n=1;
mapcache_tile *childtile;
assert(tile->grid_link->outofzoom_strategy == MAPCACHE_OUTOFZOOM_REASSEMBLE);
/* we have at most 4 tiles composing the requested tile */
mapcache_grid_get_tile_extent(ctx,tile->grid_link->grid,tile->x,tile->y,tile->z, &tile_bbox);
/*
shrink the extent so we do not fall exactly on a tile boundary, to avoid rounding
errors when computing the x,y of the lower level tile(s) we will need
*/
shrink_x = (tile_bbox.maxx - tile_bbox.minx) / (tile->grid_link->grid->tile_sx * 1000); /* 1/1000th of a pixel */
shrink_y = (tile_bbox.maxy - tile_bbox.miny) / (tile->grid_link->grid->tile_sy * 1000); /* 1/1000th of a pixel */
tile_bbox.maxx -= shrink_x;
tile_bbox.maxy -= shrink_y;
tile_bbox.minx += shrink_x;
tile_bbox.miny += shrink_y;
/* compute the x,y of the lower level tiles we'll use for reassembling (we take them from the grid_link->max_cached_zoom,
* which is the closest level were we can consume tiles from the cache
*/
mapcache_grid_get_xy(ctx,tile->grid_link->grid,tile_bbox.minx, tile_bbox.miny, tile->grid_link->max_cached_zoom, &x[0], &y[0]);
mapcache_grid_get_xy(ctx,tile->grid_link->grid,tile_bbox.maxx, tile_bbox.maxy, tile->grid_link->max_cached_zoom, &x[1], &y[1]);
if(x[0] != x[1] || y[0] != y[1]) {
/* no use computing these if the first two were identical */
n = 4;
mapcache_grid_get_xy(ctx,tile->grid_link->grid,tile_bbox.minx, tile_bbox.maxy, tile->grid_link->max_cached_zoom, &x[2], &y[2]);
mapcache_grid_get_xy(ctx,tile->grid_link->grid,tile_bbox.maxx, tile_bbox.miny, tile->grid_link->max_cached_zoom, &x[3], &y[3]);
}
tile_bbox.maxx += shrink_x;
tile_bbox.maxy += shrink_y;
tile_bbox.minx -= shrink_x;
tile_bbox.miny -= shrink_y;
childtile = mapcache_tileset_tile_clone(ctx->pool,tile);
childtile->z = tile->grid_link->max_cached_zoom;
scalefactor = childtile->grid_link->grid->levels[childtile->z]->resolution/tile->grid_link->grid->levels[tile->z]->resolution;
tile->nodata = 1;
for(i=0;i<n;i++) {
mapcache_extent childtile_bbox;
double dstminx,dstminy;
childtile->x = x[i];
childtile->y = y[i];
mapcache_tileset_tile_get(ctx,childtile);
GC_CHECK_ERROR(ctx);
if(childtile->nodata) {
/* silently skip empty tiles */
childtile->nodata = 0; /* reset flag */
continue;
}
if(!childtile->raw_image) {
childtile->raw_image = mapcache_imageio_decode(ctx, childtile->encoded_data);
GC_CHECK_ERROR(ctx);
}
if(tile->nodata) {
/* we defer the creation of the actual image bytes, no use allocating before knowing
that one of the child tiles actually contains data*/
tile->raw_image = mapcache_image_create_with_data(ctx,tile->grid_link->grid->tile_sx, tile->grid_link->grid->tile_sy);
tile->nodata = 0;
}
/* now copy/scale the srcimage onto the destination image */
mapcache_grid_get_tile_extent(ctx,childtile->grid_link->grid,
childtile->x, childtile->y, childtile->z, &childtile_bbox);
/*compute the pixel position of top left corner*/
dstminx = (childtile_bbox.minx-tile_bbox.minx)/tile->grid_link->grid->levels[tile->z]->resolution;
dstminy = (tile_bbox.maxy-childtile_bbox.maxy)/tile->grid_link->grid->levels[tile->z]->resolution;
/*
* ctx->log(ctx, MAPCACHE_DEBUG, "factor: %g. start: %g,%g (im size: %g)",scalefactor,dstminx,dstminy,scalefactor*256);
*/
if(scalefactor <= tile->grid_link->grid->tile_sx/2) /*FIXME: might fail for non-square tiles, also check tile_sy */
mapcache_image_copy_resampled_bilinear(ctx,childtile->raw_image,tile->raw_image,dstminx,dstminy,scalefactor,scalefactor,1);
else {
/* no use going through bilinear resampling if the requested scalefactor maps less than 4 pixels onto the
* resulting tile, plus pixman has some rounding bugs in this case, see
* https://bugs.freedesktop.org/show_bug.cgi?id=46277 */
unsigned int row,col;
unsigned char *srcpixptr;
unsigned char *row_ptr;
unsigned int dstminxi = - dstminx / scalefactor;
unsigned int dstminyi = - dstminy / scalefactor;
srcpixptr = &(childtile->raw_image->data[dstminyi * childtile->raw_image->stride + dstminxi * 4]);
/*
ctx->log(ctx, MAPCACHE_WARN, "factor: %g. pixel: %d,%d (val:%d)",scalefactor,dstminxi,dstminyi,*((unsigned int*)srcpixptr));
*/
row_ptr = tile->raw_image->data;
for(row=0;row<tile->raw_image->h;row++) {
unsigned char *pix_ptr = row_ptr;
for(col=0;col<tile->raw_image->w;col++) {
*((unsigned int*)pix_ptr) = *((unsigned int*)srcpixptr);
pix_ptr += 4;
}
row_ptr += tile->raw_image->stride;
}
}
/* do some cleanup, a bit in advance as we won't be using this tile's data anymore */
apr_pool_cleanup_run(ctx->pool,childtile->raw_image->data,(void*)free);
childtile->raw_image = NULL;
childtile->encoded_data = NULL;
}
}
void mapcache_tileset_outofzoom_get(mapcache_context *ctx, mapcache_tile *tile) {
assert(tile->grid_link->outofzoom_strategy != MAPCACHE_OUTOFZOOM_NOTCONFIGURED);
if(tile->grid_link->outofzoom_strategy == MAPCACHE_OUTOFZOOM_REASSEMBLE) {
mapcache_tileset_assemble_out_of_zoom_tile(ctx, tile);
} else {/* if(tile->grid_link->outofzoom_strategy == MAPCACHE_OUTOFZOOM_PROXY) */
if(ctx->config->non_blocking) {
ctx->set_error(ctx,404,"cannot proxy out-of-zoom tile, I'm configured in non-blocking mode");
return;
}
ctx->set_error(ctx,500,"Proxying out of zoom tiles not implemented");
}
}
int mapcache_tileset_tile_get_readonly(mapcache_context *ctx, mapcache_tile *tile) {
int ret = mapcache_cache_tile_get(ctx, tile->tileset->_cache, tile);
if(GC_HAS_ERROR(ctx))
return ret;
if(ret == MAPCACHE_SUCCESS && tile->tileset->auto_expire && tile->mtime && tile->tileset->source && !tile->tileset->read_only) {
/* the cache is in auto-expire mode, and can return the tile modification date,
* and there is a source configured so we can possibly update it,
* so we check to see if it is stale */
apr_time_t now = apr_time_now();
apr_time_t stale = tile->mtime + apr_time_from_sec(tile->tileset->auto_expire);
if(stale<now) {
mapcache_tileset_tile_delete(ctx,tile,0);
if(ctx->get_error(ctx) == 404) {
ctx->clear_errors(ctx);
}
ret = MAPCACHE_CACHE_MISS;
}
}
return ret;
}
typedef struct {
mapcache_tile *tile;
int cache_status;
} mapcache_subtile;
static void mapcache_tileset_tile_get_without_subdimensions(mapcache_context *ctx, mapcache_tile *tile, int read_only);
void mapcache_tileset_tile_set_get_with_subdimensions(mapcache_context *ctx, mapcache_tile *tile) {
apr_array_header_t *subtiles;
mapcache_extent extent;
mapcache_subtile st;
mapcache_image *assembled_image = NULL;
mapcache_buffer *assembled_buffer = NULL;
int i,j,k,n_subtiles = 1,assembled_nodata = 1;
/* we can be here in two cases:
* - either we didn't look up the tile directly (need to split dimension into sub-dimension and reassemble dynamically)
* - either the direct lookup failed and we need to render/assemble the tiles from subdimensions
*/
subtiles = apr_array_make(ctx->pool,1,sizeof(mapcache_subtile));
st.tile = tile;
APR_ARRAY_PUSH(subtiles,mapcache_subtile) = st;
mapcache_grid_get_tile_extent(ctx,tile->grid_link->grid,tile->x,tile->y,tile->z,&extent);
if(GC_HAS_ERROR(ctx)) goto cleanup;
for(i=0;i<tile->dimensions->nelts; i++) {
mapcache_requested_dimension *rdim = APR_ARRAY_IDX(tile->dimensions,i,mapcache_requested_dimension*);
apr_array_header_t *single_subdimension = mapcache_dimension_get_entries_for_value(ctx,rdim->dimension,rdim->requested_value,
tile->tileset, &extent, tile->grid_link->grid);
if(GC_HAS_ERROR(ctx)) /* invalid dimension given */
goto cleanup;
#ifdef DEBUG
{
char *dims = "";
int i;
for(i=0;i<single_subdimension->nelts;i++)
dims = apr_pstrcat(ctx->pool,dims,APR_ARRAY_IDX(single_subdimension,i,char*)," ",NULL);
ctx->log(ctx,MAPCACHE_DEBUG,"tile (%d,%d,%d) dimension (%s) returned: %s",
tile->z,tile->y,tile->x,rdim->dimension->name,dims);
}
#endif
if(single_subdimension->nelts == 0) {
/* not an error, but no subdimension was found: we need to return an empty tile */
tile->nodata = 1;
if(tile->tileset->store_dimension_assemblies) {
tile->raw_image = mapcache_image_create_with_data(ctx,tile->grid_link->grid->tile_sx, tile->grid_link->grid->tile_sy);
tile->raw_image->has_alpha = MC_ALPHA_YES;
tile->raw_image->is_blank = MC_EMPTY_YES;
tile->encoded_data = tile->tileset->format->write(ctx, tile->raw_image, tile->tileset->format);
/* set the key for the dimension so it can be stored with the requested dimension */
for(j=0;j<tile->dimensions->nelts;j++) {
mapcache_requested_dimension *dim = APR_ARRAY_IDX(tile->dimensions,j,mapcache_requested_dimension*);
dim->cached_value = dim->requested_value;
}
mapcache_cache_tile_set(ctx, tile->tileset->_cache, tile);
GC_CHECK_ERROR(ctx);
}
return;
} else {
for(j=0;j<n_subtiles;j++) {
/* clone the existing subtiles if we have more than one sub-dimension to assemble for the the current dimension */
for(k=1;k<single_subdimension->nelts;k++) {
st.tile = mapcache_tileset_tile_clone(ctx->pool,APR_ARRAY_IDX(subtiles,j,mapcache_subtile).tile);
APR_ARRAY_PUSH(subtiles,mapcache_subtile)=st;
}
}
n_subtiles *= single_subdimension->nelts;
/* foreach of the subtiles, now set the actual subdimension we are going to be using
the "j%nelts" part takes care of looping over and over through the individual subdimensions */
for(j=0;j<n_subtiles;j++) {
mapcache_tile_set_cached_dimension(ctx,APR_ARRAY_IDX(subtiles,j,mapcache_subtile).tile,rdim->dimension->name,
APR_ARRAY_IDX(single_subdimension,j%single_subdimension->nelts,char*));
}
}
}
/* our subtiles array now contains a list of tiles with subdimensions split up, we now need to fetch them from the cache */
/* note that subtiles[0].tile == tile */
for(i=subtiles->nelts-1; i>=0; i--) {
mapcache_tile *subtile = APR_ARRAY_IDX(subtiles,i,mapcache_subtile).tile;
mapcache_tileset_tile_get_without_subdimensions(ctx, subtile, (tile->tileset->subdimension_read_only||!tile->tileset->source)?1:0); /* creates the tile from the source, takes care of metatiling */
if(GC_HAS_ERROR(ctx))
goto cleanup;
if(!subtile->nodata) {
assembled_nodata = 0;
if(!assembled_buffer && !assembled_image) {
/* first "usable" subtile */
assembled_buffer = subtile->encoded_data;
assembled_image = subtile->raw_image;
} else {
/* need to merge current assembled tile over this subtile */
if(!assembled_image) {
assembled_image = mapcache_imageio_decode(ctx,assembled_buffer);
if(GC_HAS_ERROR(ctx))
goto cleanup;
assembled_buffer = NULL; /* the image data went stale as we're merging something */
}
if(!subtile->raw_image) {
subtile->raw_image = mapcache_imageio_decode(ctx,subtile->encoded_data);
if(GC_HAS_ERROR(ctx))
goto cleanup;
}
mapcache_image_merge(ctx, subtile->raw_image, assembled_image);
assembled_image = subtile->raw_image;
assembled_image->has_alpha = MC_ALPHA_UNKNOWN; /* we've merged two images, we now have no idea if it's transparent or not */
if(GC_HAS_ERROR(ctx))
goto cleanup;
}
if ((mapcache_imageio_alpha_sniff(ctx,subtile->encoded_data) == MC_ALPHA_NO) ||
(subtile->raw_image && subtile->raw_image->has_alpha == MC_ALPHA_NO)) {
/* the returned image is fully opaque, we don't need to get/decode/merge any further subtiles */
if(assembled_image)
assembled_image->has_alpha = MC_ALPHA_NO;
break;
}
}
}
tile->encoded_data = assembled_buffer;
tile->raw_image = assembled_image;
tile->nodata = assembled_nodata;
/* TODO: how should the no data case be handled generically?
* uncomment the following block if this nodata state should be returned to
* the requester immediately, without this info being stored to the cache.
* Leaving this uncommented will cause a no-data tile to be (maybe, depending
* on the cache's actual configuration) written to the cache
*/
/*
if(tile->nodata) {
goto cleanup;
}
*/
if(!tile->nodata && !tile->encoded_data) {
tile->encoded_data = tile->tileset->format->write(ctx, tile->raw_image, tile->tileset->format);
GC_CHECK_ERROR(ctx);
}
if(tile->tileset->store_dimension_assemblies) {
int already_stored = 1; /*depending on the type of dimension, we may have no nead to store the resulting tile*/
if(n_subtiles != 1)
already_stored = 0; /*if we had to merge multiple subdimensions, then we always have to store the resulting assembly*/
/* set the key for the dimension so it can be stored with the requested dimension */
for(j=0;j<tile->dimensions->nelts;j++) {
mapcache_requested_dimension *dim = APR_ARRAY_IDX(tile->dimensions,j,mapcache_requested_dimension*);
if(strcmp(dim->cached_value,dim->requested_value)) {
already_stored = 0; /*the subdimension is different than the requested dimension, we need to store the resulting tile*/
}
dim->cached_value = dim->requested_value;
}
if(!already_stored) {
if(tile->nodata) {
tile->raw_image = mapcache_image_create_with_data(ctx,tile->grid_link->grid->tile_sx, tile->grid_link->grid->tile_sy);
tile->raw_image->has_alpha = MC_ALPHA_YES;
tile->raw_image->is_blank = MC_EMPTY_YES;
tile->encoded_data = tile->tileset->format->write(ctx, tile->raw_image, tile->tileset->format);
GC_CHECK_ERROR(ctx);
}
mapcache_cache_tile_set(ctx, tile->tileset->_cache, tile);
GC_CHECK_ERROR(ctx);
}
}
cleanup:
return;
}
void mapcache_tileset_tile_get_with_subdimensions(mapcache_context *ctx, mapcache_tile *tile) {
int i,ret;
assert(tile->dimensions);
if(tile->tileset->store_dimension_assemblies) {
for(i=0;i<tile->dimensions->nelts;i++) {
mapcache_requested_dimension *dim = APR_ARRAY_IDX(tile->dimensions,i,mapcache_requested_dimension*);
dim->cached_value = dim->requested_value;
}
ret = mapcache_tileset_tile_get_readonly(ctx,tile);
GC_CHECK_ERROR(ctx);
if(ret == MAPCACHE_SUCCESS) {
/* update the tile expiration time */
if(tile->tileset->auto_expire && tile->mtime) {
apr_time_t now = apr_time_now();
apr_time_t expire_time = tile->mtime + apr_time_from_sec(tile->tileset->auto_expire);
tile->expires = apr_time_sec(expire_time-now);
}
return;
}
for(i=0;i<tile->dimensions->nelts;i++) {
/* unset the cached dimension we setup earlier on */
mapcache_requested_dimension *dim = APR_ARRAY_IDX(tile->dimensions,i,mapcache_requested_dimension*);
dim->cached_value = NULL;
}
}
return mapcache_tileset_tile_set_get_with_subdimensions(ctx,tile);
}
/**
* \brief return the image data for a given tile
* this call uses a global (interprocess+interthread) mutex if the tile was not found
* in the cache.