Applies To:
  • CitectSCADA 3.00

I have a bitmap, CYCLONE.BMP, in the project directory and I displayed it at AN 25 on a page using the following cicode: DspBmp(25, "CYCLONE.BMP", 0). While still running Citect I switched to paintbrush and edited CYCLONE.BMP and the new version was saved over the existing one. When I tried to display the new bitmap in Citect it displayed the old one instead. Why? 

In Citect bitmaps are used extensively in animations. To speed up the displaying of bitmaps Citect will cache the bitmaps. That is, when a particular bitmap is needed it will be loaded into memory but when it is no longer needed it will remain in memory provided that enough memory is available. Only if memory resources become scarce, will unused bitmaps be discarded. So in the example given the first time CYCLONE.BMP is displayed it is loaded into the cache. The next time you call DspBmp to display CYCLONE.BMP Citect will check to see if the bitmap is on the cache and if it is will take it from there. Hence even though the physical file has changed the old bitmap image is still displayed.