This document is a collection of miscellaneous SCASM infos.

• Filenames:
  Filenames and parameter-strings for macros/includes can now contain blanc characters if the string is surrounded by quotation marks. The maximum length for filenames is 260 characters. However, macro parameter strings are limited to 36 characters.
   
• Precision:
  The precision of the positioning system has been increased in SCASM 2.50. In older versions the smallest positioning unit in north south direction was 1 meter. Now the smallest unit for north south direction is 1/128 meter (abt. 0.78cm or 5/16 inch). So if you recompile older sceneries with this new SCASM version you should (visually) check critical object positions. But not all BGL instructions are using the full format.

 

• Line buffer overflow:
  If you get a "line buffer overflow" message during compile time you can set a larger buffer size by using the -LB ## command line switch or better a Set() command which is available since SCASM 2.47. The normal size of the line buffer is 20kb. A larger buffer is only needed for commands with very long data lists like Points() or VecPoints() or VertexList().

 

• Buffers / Labels
  If you have problems with the scenery buffer size or with the maximum label number please see Set() command with the BUF or LABELS parameter.

 

• Using numbers for Labels:
  It is possible to enter any number value as a Label. This is usefull if you need a fix external reference. In .MDL files this is used to work with a reserved data space. The Format is : [<expression>]. Where <expression> is any valid math expression. The simplest expression is a number. The ":" is needed by SCASM to recognise "this is a place for a label". The "[...]" are needed to indicate that the value should not be taken from the internal symbol table but from this expression. Example: VarBase( :[ -1 ] )

 

• Calculating with Labels:
  Sometimes it usefull to calculate with Labels. The trick is to do it within "[...]". These are used to indicate to SCASM that there is something to calculate. You can use any label within expressions but it must be already defined in a previous line. Also you have to avoid to confuse SCASMs simple expresion evaluator so be sure the labels and operators are always separated by spaces. The result may be truncated to fit into the required data unit. Example:

  Dwx( [ :Label_2 - :Label_1] ) or
  Dwx( [ :Start_of_Table + [ $Length_of_Entry * 8] ] )
   

• Multiple error messages
  SCASM scanns the source files several times. There is one scan for every data section in the BGL file. For this reason SCASM sometimes recognises the same error again and again. Also it may happen that one error triggers several aditional error messages. In this case it may help to activate the SCAERROR.LOG file (-L command line parameter) to see them all.
  For example you may see tons of this error messages:
  

  > Error in include file exisland.txt line 90
  > -> EndA
  > -> Macro parameter count error

  This is not very helpfull. The reason for this is that an Area() - EndA block is not fully decoded during every scan and only formal errors are found then. But there is ONE message telling you the real problem:
  

  > Error in include file exisland.txt line 57
  > -> RefPoint( %7 : 1 54:11:13 342:55:00 )
  > -> Macro parameter count error
  

• FS2K and later uses Z-Buffering on polygon level wheras previous versions did this on object level. This is why you normally do not longer need VectorJumps() in objects to avoid bleed through effects. But it seems that single points and lines are not sorted in the Z-Buffer. If you have bleed through problems with these elements, try to solve them by using VectorJump() commands as we did it in the past.
   
• During the installation of new scenery to FS2K it sometimes happens that the file SCENERY.CFG was set to "write protected". The result is that this file cannot be updated and FS2K will not show the scenery. Use Windows Explorer/Properties to "uncheck" the "read only" file attribute.
   
• If you exclude visual scenery elements in CFS1 it seems that you are also excluding your ground elevation definition at least if they are defined with instructions I_A3() and/or I_A9(). If this happens you have to inlude a "flat replacement" for them in your scenery.
  You will recognise this problem by a messup of the screen display. Changeing the view to "up" and then return to the normal view will give you a correct screen display for a short moment.
   
• One of the new features of CFS1 is the ability to handle .BMP files. These must be uncompressed bitmaps with a color palette. The BMP's can have an individual color palette. We are not longer bound to an FS internal palette. Usual sizes of CFS bitmaps are:

  256	*	256
  128	*	128
  64	*	64
  32	*	32

  The Pixel coordinates for an 256 * 256 BMP are: 0, 0 lower left (sw) 255, 255 upper right (ne). The small bitmaps are internally expanded to 256 * 256.