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Hi,<br>this is a message/question for grads developers...<br><br>A short while back I saw some messages go by regarding the mysterious 'memory allocation errors' in gxhpng when drawing large shapefiles and using printim.<br>I ran into this problem yesterday when trying to draw gshhs shapefiles (using the new, built-in 'draw shp' command).<br><br>I dug into the source code and did some debugging.<br>It turns out that the grads metabuffer is based on using short (16-bit) integers.<br>So, regardless of the amount of memory your system has, the maximum number of polygon vertices that can be stored in the buffer is 32,767.<br><br>In my case, the gshhs shapefile I was trying to draw had about 40,000 vertices. <br>Since this value couldnt be stored in the metabuffer, I was getting a 'junk' negative value for the polygon vertext count, and this was causing the memory allocation to fail.<br><br>My quick&dirty workaround was to upgrade the metabuffer's 'short ints' to regular 'gaint' datatypes.<br>I guess this effectively doubles the memory usage of the metabuffer & grads in general.<br>However, it solved the problem...<br><br>I didnt try converting to 'unsigned short' integers in the metabuffer read/write routines, <br>but perhaps this could be implemented instead of being forced to use long integers?<br><br>pablo<br> </body>
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