Refactoring towards SLD "painter's model" implementation

MapServer · Feb 20, 2020 · 2b80a45 · 2b80a45
1 parent 48cfca5
commit 2b80a45
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Showing 3 changed files with 34 additions and 21 deletions.
diff --git a/mapdraw.c b/mapdraw.c
@@ -928,6 +928,7 @@ int msDrawVectorLayer(mapObj *map, layerObj *layer, imageObj *image)
   char        cache=MS_FALSE;
   int         maxnumstyles=1;
   featureListNodeObjPtr shpcache=NULL, current=NULL;
+  int classindex = -1;
   int nclasses = 0;
   int *classgroup = NULL;
   double minfeaturesize = -1;
@@ -1004,9 +1005,6 @@ int msDrawVectorLayer(mapObj *map, layerObj *layer, imageObj *image)
     return MS_FAILURE;
   }
 
-  /* step through the target shapes */
-  msInitShape(&shape);
-
   nclasses = 0;
   classgroup = NULL;
   if(layer->classgroup && layer->numclasses > 0)
@@ -1015,24 +1013,34 @@ int msDrawVectorLayer(mapObj *map, layerObj *layer, imageObj *image)
   if(layer->minfeaturesize > 0)
     minfeaturesize = Pix2LayerGeoref(map, layer, layer->minfeaturesize);
 
-  while((status = msLayerNextShape(layer, &shape)) == MS_SUCCESS) {
 
-    /* Check if the shape size is ok to be drawn */
-    if((shape.type == MS_SHAPE_LINE || shape.type == MS_SHAPE_POLYGON) && (minfeaturesize > 0) && (msShapeCheckSize(&shape, minfeaturesize) == MS_FALSE)) {
-      if(layer->debug >= MS_DEBUGLEVEL_V)
-        msDebug("msDrawVectorLayer(): Skipping shape (%ld) because LAYER::MINFEATURESIZE is bigger than shape size\n", shape.index);
-      msFreeShape(&shape);
-      continue;
+  /* step through the target shapes and their classes */
+  msInitShape(&shape);
+  classindex = -1;
+  for (;;) {
+    if (classindex == -1) {
+      status = msLayerNextShape(layer, &shape);
+      if (status != MS_SUCCESS) {
+        break;
+      }
+
+      /* Check if the shape size is ok to be drawn */
+      if((shape.type == MS_SHAPE_LINE || shape.type == MS_SHAPE_POLYGON) && (minfeaturesize > 0) && (msShapeCheckSize(&shape, minfeaturesize) == MS_FALSE)) {
+        if(layer->debug >= MS_DEBUGLEVEL_V)
+          msDebug("msDrawVectorLayer(): Skipping shape (%ld) because LAYER::MINFEATURESIZE is bigger than shape size\n", shape.index);
+        continue;
+      }
     }
 
-    shape.classindex = msShapeGetClass(layer, map, &shape, classgroup, nclasses);
-    if((shape.classindex == -1) || (layer->class[shape.classindex]->status == MS_OFF)) {
-      msFreeShape(&shape);
+    classindex = msShapeGetNextClass(classindex, layer, map, &shape, classgroup, nclasses);
+    if((classindex == -1) || (layer->class[classindex]->status == MS_OFF)) {
       continue;
     }
+    shape.classindex = classindex;
+    classindex = -1; // This value indicates that no more class is to be
+                     // fetched from current shape
 
     if(maxfeatures >=0 && featuresdrawn >= maxfeatures) {
-      msFreeShape(&shape);
       status = MS_DONE;
       break;
     }
@@ -1055,14 +1063,12 @@ int msDrawVectorLayer(mapObj *map, layerObj *layer, imageObj *image)
       if(strcasecmp(layer->styleitem, "AUTO") == 0) {
         if(msLayerGetAutoStyle(map, layer, layer->class[shape.classindex], &shape) != MS_SUCCESS) {
           retcode = MS_FAILURE;
-          msFreeShape(&shape);
           break;
         }
       } else {
         /* Generic feature style handling as per RFC-61 */
         if(msLayerGetFeatureStyle(map, layer, layer->class[shape.classindex], &shape) != MS_SUCCESS) {
           retcode = MS_FAILURE;
-          msFreeShape(&shape);
           break;
         }
       }
@@ -1110,28 +1116,25 @@ int msDrawVectorLayer(mapObj *map, layerObj *layer, imageObj *image)
     else
       status = msDrawShape(map, layer, &shape, image, -1, drawmode); /* all styles  */
     if(status != MS_SUCCESS) {
-      msFreeShape(&shape);
       retcode = MS_FAILURE;
       break;
     }
 
     if(shape.numlines == 0) { /* once clipped the shape didn't need to be drawn */
-      msFreeShape(&shape);
       continue;
     }
 
     if(cache) {
       if(insertFeatureList(&shpcache, &shape) == NULL) {
-        msFreeShape(&shape);
         retcode = MS_FAILURE; /* problem adding to the cache */
         break;
       }
     }
 
     maxnumstyles = MS_MAX(maxnumstyles, layer->class[shape.classindex]->numstyles);
 
-    msFreeShape(&shape);
   }
+  msFreeShape(&shape);
 
   if (classgroup)
     msFree(classgroup);

diff --git a/mapserver.h b/mapserver.h
@@ -2680,6 +2680,7 @@ void msPopulateTextSymbolForLabelAndString(textSymbolObj *ts, labelObj *l, char
   MS_DLL_EXPORT int msEvalContext(mapObj *map, layerObj *layer, char *context);
   MS_DLL_EXPORT int msEvalExpression(layerObj *layer, shapeObj *shape, expressionObj *expression, int itemindex);
   MS_DLL_EXPORT int msShapeGetClass(layerObj *layer, mapObj *map, shapeObj *shape, int *classgroup, int numclasses);
+  MS_DLL_EXPORT int msShapeGetNextClass(int currentclass, layerObj *layer, mapObj *map, shapeObj *shape, int *classgroup, int numclasses);
   MS_DLL_EXPORT int msShapeCheckSize(shapeObj *shape, double minfeaturesize);
   MS_DLL_EXPORT char* msShapeGetLabelAnnotation(layerObj *layer, shapeObj *shape, labelObj *lbl);
   MS_DLL_EXPORT int msGetLabelStatus(mapObj *map, layerObj *layer, shapeObj *shape, labelObj *lbl);

diff --git a/maputil.c b/maputil.c
@@ -657,14 +657,23 @@ int *msAllocateValidClassGroups(layerObj *lp, int *nclasses)
 }
 
 int msShapeGetClass(layerObj *layer, mapObj *map, shapeObj *shape, int *classgroup, int numclasses)
+{
+  return msShapeGetNextClass(-1, layer, map, shape, classgroup, numclasses);
+}
+
+int msShapeGetNextClass(int currentclass, layerObj *layer, mapObj *map,
+    shapeObj *shape, int *classgroup, int numclasses)
 {
   int i, iclass;
 
+  if (currentclass < 0)
+    currentclass = -1;
+
   if (layer->numclasses > 0) {
     if (classgroup == NULL || numclasses <=0)
       numclasses = layer->numclasses;
 
-    for(i=0; i<numclasses; i++) {
+    for(i=currentclass+1; i<numclasses; i++) {
       if (classgroup)
         iclass = classgroup[i];
       else