pfm-resize-quick, and let pfm-resize-gaussian default to false

panda/src/pnmimage/config_pnmimage.cxx

@@ -37,12 +37,19 @@ ConfigVariableBool pfm_reverse_dimensions
           "on input.  Does not affect output, which is always written width height."));
 
 ConfigVariableBool pfm_resize_gaussian
-("pfm-resize-gaussian", true,
+("pfm-resize-gaussian", false,
  PRC_DESC("Specify true to implement PfmFile::resize() with a higher-quality "
           "Gaussian filter, or false to implement it with a faster box "
           "filter.  This just controls the behavior of resize(); you can "
           "always call box_filter() or gaussian_filter() explicitly."));
 
+ConfigVariableBool pfm_resize_quick
+("pfm-resize-quick", true,
+ PRC_DESC("If pfm-resize-gaussian is false, set this true to allow the "
+          "so-called \"quick\" filter when the pfm is being downscaled.  This "
+          "is even faster than the normal box filter.  In some cases it "
+          "may also be more precise, though it may be more aliased."));
+
 ConfigVariableDouble pfm_resize_radius
 ("pfm-resize-radius", 1.0,
  PRC_DESC("Specify the default filter radius for PfmFile::resize().  "

panda/src/pnmimage/config_pnmimage.h

@@ -25,6 +25,7 @@ NotifyCategoryDecl(pnmimage, EXPCL_PANDA_PNMIMAGE, EXPTP_PANDA_PNMIMAGE);
 extern ConfigVariableBool pfm_force_littleendian;
 extern ConfigVariableBool pfm_reverse_dimensions;
 extern ConfigVariableBool pfm_resize_gaussian;
+extern ConfigVariableBool pfm_resize_quick;
 extern ConfigVariableDouble pfm_resize_radius;
 
 extern EXPCL_PANDA_PNMIMAGE void init_libpnmimage();

panda/src/pnmimage/pfmFile.cxx

@@ -992,7 +992,7 @@ resize(int new_x_size, int new_y_size) {
   if (pfm_resize_gaussian) {
     result.gaussian_filter_from(pfm_resize_radius, *this);
   } else {
-    if (new_x_size <= _x_size && new_y_size <= _y_size) {
+    if (pfm_resize_quick && new_x_size <= _x_size && new_y_size <= _y_size) {
       // If we're downscaling, we can use quick_filter, which is faster.
       result.quick_filter_from(*this);