Roam and Wms optimizations

[aweather] / src / gis / wms.c

diff --git a/src/gis/wms.c b/src/gis/wms.c
index 51f69bc8ca8379189d134027cdf493b1f1bfab88..92a3476a8422c73e0422e84acaa330aa026ac884 100644 (file)
--- a/src/gis/wms.c
+++ b/src/gis/wms.c
@@ -79,7 +79,8 @@ gchar *wms_make_uri(WmsInfo *info, gdouble xmin, gdouble ymin, gdouble xmax, gdo
 /****************
  * WmsCacheNode *
  ****************/
-WmsCacheNode *wms_cache_node_new(gdouble xmin, gdouble ymin, gdouble xmax, gdouble ymax)
+WmsCacheNode *wms_cache_node_new(WmsCacheNode *parent,
+               gdouble xmin, gdouble ymin, gdouble xmax, gdouble ymax, gint width)
 {
        WmsCacheNode *self = g_new0(WmsCacheNode, 1);
        //g_debug("WmsCacheNode: new - %p %+7.3f,%+7.3f,%+7.3f,%+7.3f",
@@ -88,6 +89,11 @@ WmsCacheNode *wms_cache_node_new(gdouble xmin, gdouble ymin, gdouble xmax, gdoub
        self->latlon[1] = ymin;
        self->latlon[2] = xmax;
        self->latlon[3] = ymax;
+       self->parent    = parent;
+       if (ymin <= 0 && ymax >= 0)
+               self->res = ll2m(xmax-xmin, 0)/width;
+       else
+               self->res = ll2m(xmax-xmin, MIN(ABS(ymin),ABS(ymax)))/width;
        return self;
 }
 
@@ -125,10 +131,10 @@ WmsInfo *wms_info_new(WmsLoader loader, WmsFreeer freeer,
        self->width        = width;
        self->height       = height;
 
-       self->max_age      = 30;
+       self->max_age      = 60;
        self->atime        = time(NULL);
        self->gc_source    = g_timeout_add_seconds(1, (GSourceFunc)wms_info_gc, self);
-       self->cache_root   = wms_cache_node_new(-180, -90, 180, 90);
+       self->cache_root   = wms_cache_node_new(NULL, -180, -90, 180, 90, width);
        self->soup         = soup_session_async_new();
        return self;
 }
@@ -225,8 +231,8 @@ void wms_info_cache(WmsInfo *info, gdouble resolution, gdouble lat, gdouble lon,
                }
 
                /* Break if current resolution (m/px) is good enough */
-               if (ll2m(xdist, cur_lat)/info->width < resolution  ||
-                   ll2m(xdist, cur_lat)/info->width < info->resolution)
+               if (ll2m(xdist, cur_lat)/info->width <= resolution  ||
+                   ll2m(xdist, cur_lat)/info->width <= info->resolution)
                        break;
 
                /* Get locations for the correct sub-tile */
@@ -246,7 +252,8 @@ void wms_info_cache(WmsInfo *info, gdouble resolution, gdouble lat, gdouble lon,
                g_string_append_printf(target_path, "/%d%d", xpos, ypos);
                if (target_node->children[xpos][ypos] == NULL)
                        target_node->children[xpos][ypos] =
-                               wms_cache_node_new(xmin, ymin, xmax, ymax);
+                               wms_cache_node_new(target_node,
+                                       xmin, ymin, xmax, ymax, info->width);
                target_node = target_node->children[xpos][ypos];
        }
 
@@ -297,36 +304,46 @@ void wms_info_cache(WmsInfo *info, gdouble resolution, gdouble lat, gdouble lon,
                g_string_free(target_path, TRUE);
        }
 }
-WmsCacheNode *wms_info_fetch(WmsInfo *info, gdouble resolution, gdouble lat, gdouble lon,
+/* TODO:
+ *   - Store WmsCacheNode in point and then use parent pointers to go up/down
+ *   - If resolution doesn't change, tell caller to skip remaining calculations
+ */
+WmsCacheNode *wms_info_fetch(WmsInfo *info, WmsCacheNode *root,
+               gdouble resolution, gdouble lat, gdouble lon,
                gboolean *correct)
 {
+       if (root && root->data && !root->caching &&
+           root->latlon[0] <= lon && lon <= root->latlon[2] &&
+           root->latlon[1] <= lat && lat <= root->latlon[3] &&
+           root->res <= resolution &&
+           (!root->parent || root->parent->res > resolution)) {
+               *correct = TRUE;
+               info->atime = time(NULL);
+               root->atime = info->atime;
+               return root;
+       }
+
        if (info->cache_root == NULL) {
                *correct = FALSE;
                return NULL;
        }
        WmsCacheNode *node = info->cache_root;
        WmsCacheNode *best = (node && node->data ? node : NULL);
-       gdouble x=lon, y=lat;
-       gdouble xmin=-180, ymin=-90, xmax=180, ymax=90;
-       gdouble xdist = xmax - xmin;
-       gdouble ydist = ymax - ymin;
+       gdouble xmin=-180, ymin=-90, xmax=180, ymax=90, xdist=360, ydist=180;
        gdouble cur_lat = 0;
        int xpos=0, ypos=0;
-       while (ll2m(xdist, cur_lat)/info->width > resolution  &&
-              ll2m(xdist, cur_lat)/info->width > info->resolution) {
+       gdouble cur_res = ll2m(xdist, cur_lat)/info->width;
+       while (cur_res > resolution  &&
+              cur_res > info->resolution) {
 
-               xpos = (int)(((x - xmin) / xdist) * 4);
-               ypos = (int)(((y - ymin) / ydist) * 4);
-               //g_message("%d = (int)(((%f - %f) / %f) * 4)",
-               //              xpos, x, xmin, xdist);
+               xpos = ((lon - xmin) / xdist) * 4;
+               ypos = ((lat - ymin) / ydist) * 4;
                if (xpos == 4) xpos--;
                if (ypos == 4) ypos--;
                xdist /= 4;
                ydist /= 4;
                xmin = xmin + xdist*(xpos+0);
                ymin = ymin + ydist*(ypos+0);
-               xmax = xmin + xdist;
-               ymax = ymin + ydist; 
                cur_lat = MIN(ABS(ymin), ABS(ymax));
 
                node = node->children[xpos][ypos];
@@ -334,6 +351,8 @@ WmsCacheNode *wms_info_fetch(WmsInfo *info, gdouble resolution, gdouble lat, gdo
                        break;
                if (node->data)
                        best = node;
+
+               cur_res = ll2m(xdist, cur_lat)/info->width;
        }
        if (correct)
                *correct = (node && node == best);
@@ -343,13 +362,19 @@ WmsCacheNode *wms_info_fetch(WmsInfo *info, gdouble resolution, gdouble lat, gdo
        return best;
 }
 
-WmsCacheNode *wms_info_fetch_cache(WmsInfo *info, gdouble res, gdouble lat, gdouble lon,
+WmsCacheNode *wms_info_fetch_cache(WmsInfo *info, WmsCacheNode *root,
+               gdouble res, gdouble lat, gdouble lon,
                WmsChunkCallback chunk_callback, WmsDoneCallback done_callback, gpointer user_data)
 {
+       /* Fetch a node, if it isn't cached, cache it, also keep it's parent cached */
        gboolean correct;
-       WmsCacheNode *node = wms_info_fetch(info, res, lat, lon, &correct);
+       WmsCacheNode *node = wms_info_fetch(info, root, res, lat, lon, &correct);
        if (!node || !correct)
                wms_info_cache(info, res, lat, lon, chunk_callback, done_callback, user_data);
+       //else if (node->parent && node->parent->data == NULL)
+       //      wms_info_cache(info, node->parent->res, lat, lon, chunk_callback, done_callback, user_data);
+       //else if  (node->parent)
+       //      node->parent->atime = node->atime;
        return node;
 }
 
@@ -357,8 +382,8 @@ WmsCacheNode *wms_info_fetch_cache(WmsInfo *info, gdouble res, gdouble lat, gdou
 static WmsCacheNode *wms_info_gc_cb(WmsInfo *self, WmsCacheNode *node)
 {
        gboolean empty = FALSE;
-       if (node->data && !node->caching &&
-           self->atime - node->atime > self->max_age) {
+       if (self->atime - node->atime > self->max_age &&
+           node->data && node != self->cache_root && !node->caching) {
                g_debug("WmsInfo: gc - expired node %p", node);
                self->freeer(node);
                node->data = NULL;
@@ -373,8 +398,13 @@ static WmsCacheNode *wms_info_gc_cb(WmsInfo *self, WmsCacheNode *node)
                        }
        if (empty) {
                g_debug("WmsInfo: gc - empty branch %p", node);
+               /* 
+                * TODO: Don't prune nodes while we're caching WmsCacheNodes in the Roam triangles
+                * and points
                g_free(node);
                return NULL;
+               */
+               return node;
        } else {
                return node;
        }