avoid drawing lines where two points are in the same spot. this mai be confusing...

git-svn-id: svn://svn.oetiker.ch/rrdtool/branches/1.2@667 a5681a0c-68f1-0310-ab6d-d61299d08faa

diff --git a/program/src/rrd_graph.c b/program/src/rrd_graph.c
index bb31289e3df9a07415c97d090fe1d5cb9be870f6..2a13cb54e8ed62bf461b1914b3be57d31fcad833 100644 (file)
--- a/program/src/rrd_graph.c
+++ b/program/src/rrd_graph.c
@@ -2472,31 +2472,35 @@ graph_paint(image_desc_t *im, char ***calcpr)
       if (im->gdes[i].col != 0x0){   
         /* GF_LINE and friend */
         if(stack_gf == GF_LINE ){
+          double last_y=0;
           node = NULL;
-          for(ii=1;ii<im->xsize;ii++){     
+          for(ii=1;ii<im->xsize;ii++){
            if (isnan(im->gdes[i].p_data[ii]) || (im->slopemode==1 && isnan(im->gdes[i].p_data[ii-1]))){
                node = NULL;
                continue;
            }
             if ( node == NULL ) {
+               last_y = ytr(im,im->gdes[i].p_data[ii]);
                if ( im->slopemode == 0 ){
                   node = gfx_new_line(im->canvas,
-                                    ii-1+im->xorigin,ytr(im,im->gdes[i].p_data[ii]),
-                                    ii+im->xorigin,ytr(im,im->gdes[i].p_data[ii]),
+                                    ii-1+im->xorigin,last_y,
+                                    ii+im->xorigin,last_y,
                                     im->gdes[i].linewidth,
                                     im->gdes[i].col);
                } else {
                   node = gfx_new_line(im->canvas,
                                     ii-1+im->xorigin,ytr(im,im->gdes[i].p_data[ii-1]),
-                                    ii+im->xorigin,ytr(im,im->gdes[i].p_data[ii]),
+                                    ii+im->xorigin,last_y,
                                     im->gdes[i].linewidth,
                                     im->gdes[i].col);
                }
              } else {
-              if ( im->slopemode==0 ){
-                   gfx_add_point(node,ii-1+im->xorigin,ytr(im,im->gdes[i].p_data[ii]));
+               double new_y = ytr(im,im->gdes[i].p_data[ii]);
+              if ( im->slopemode==0 && new_y != last_y){
+                   gfx_add_point(node,ii-1+im->xorigin,new_y);
+                   last_y = new_y;
               };
-               gfx_add_point(node,ii+im->xorigin,ytr(im,im->gdes[i].p_data[ii]));
+               gfx_add_point(node,ii+im->xorigin,new_y);
              };
 
           }