Code:

---

string file_name = "t";
string file_type = ".pcx";
string file;
string file_number;

panel transform_l01_normal
{
	flags = d3d, visible;
	layer = 11;
}

function random_panel()
{
  var i;
  i = int(random(3))+1;
  str_cpy(file,file_name);
  str_for_num(file_number,i);
  str_cat(file,file_number);
  str_cat(file,file_type);
  
  transform_l01_normal.bmap = file;
}

---

i have some files (t1.pcx, t2.pcx, t3.pcx,....).
where is the error?
the game crashes if i call this function...

transform_l01_normal.bmap = file; This is the problem. You're trying to assign a string to a bmap. Try this:
bmap* bmap_ptr; // define this outside of the function.

bmap_ptr = bmap_create(STRING* name);
transform_l01_normal.bmap = bmap_ptr;

error:
"non existing/empty function bmap_create"

and instead of "STRING* name" i have to write "file", as this is my filename-string. am i right?

Yes you are right. To use this instruction you'll need the 6.40 beta version I think.. You can find it in the updates & announcements forum.

isn't there another way? i don't really want to install a beta update.

you can do it the long ugly way. define all the panels seperately with the separate bitmaps and then use a random to view the different panels each time you call the panel.

long and ugly, but it'll do ya!

Yea, you could define all bitmaps and store their handles in an array. Something like this:

bmap t1 = <t1.bmp>;
bmap t2 = <t2.bmp>;
bmap t3 = <t3.bmp>;
var bitmap_array[3];
starter store_bmaps()
{
bitmap_array[0] = handle(t1);
bitmap_array[1] = handle(t2);
bitmap_array[2] = handle(t3);
}

then in the function use:
function random_panel()
{
var i;
i = int(random(3))+1;
bmap_ptr = ptr_for_handle(bitmap_array);
transform_l01_normal.bmap = bmap_ptr;
}