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git-svn-id: http://svn.code.sf.net/p/netpbm/code/trunk@4252 9d0c8265-081b-0410-96cb-a4ca84ce46f8

1 files changed, 9 insertions, 0 deletions

diff --git a/analyzer/pgmtexture.c b/analyzer/pgmtexture.c
index c69643e7..72f660f1 100644
--- a/analyzer/pgmtexture.c
+++ b/analyzer/pgmtexture.c
@@ -49,7 +49,16 @@ static bool const sortit = FALSE;
 static float *
 vector(unsigned int const nl,
        unsigned int const nh) {
+/*----------------------------------------------------------------------------
+  Allocate a float vector with range [nl..nh]
+
+  We do some seedy C here, subtracting an arbitrary integer from a pointer and
+  calling the result a pointer.  It normally works because the only way we'll
+  use that pointer is by adding that same integer or something greater to it.
 
+  The point of this is not to allocate memory for vector elements that will
+  never be referenced (component < nl).
+-----------------------------------------------------------------------------*/
     float * v;
 
     assert(nh >= nl);