Difference between revisions of "Gamevar operators"

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m (Reverted edits by Rasmusthorup (talk) to last revision by Helixhorned)
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For example:
For example:


  setvar temp 3 // assigns a value of 1 to the gamevar ''temp''. Am i reading this wrong? Rasmusthorup.
  setvar temp 3 // assigns a value of 1 to the gamevar ''temp''.
   
   
  addvar temp 1 // adds 1 to ''temp'', causing its value to become 2.
  addvar temp 1 // adds 1 to ''temp'', causing its value to become 2.

Revision as of 15:42, 18 April 2012

<operator>var <gamevar> <value>
<operator>varvar <gamevar> <value>

Gamevar operators are commands that perform various mathematical and bitwise logical operations on gamevars. The first argument must be a writable gamevar and is taken as the destination as well and the first operand (2-address code).

For example:

setvar temp 3 // assigns a value of 1 to the gamevar temp.

addvar temp 1 // adds 1 to temp, causing its value to become 2.

mulvar temp 2 // multiplies temp by 2, causing its value to become 4.
Operator C/C++ Math Description Notes
set = = assignment
add + + addition
sub - subtraction
mul * × multiplication
div / ÷ division with rounding toward 0 Ensure that <value> does not equal 0 at any time.
mod % modulo, remainder Ensure that <value> does not equal 0 at any time; It is undefined whether the sign of the result follows the divisor or the dividend (for now). sign of the result is that of left hand side operand
and & bitwise AND The bits in the result are set only if they were set in both of the values being operated on. Ex.:

01001010 AND
11110100 is
01000000

or | bitwise OR The bits in the result are set only if they were set in either of the values being operated on. Ex.:

01001010 OR
11110100 is
11111110

xor ^ bitwise XOR The bits in the result are set if only one of the values being operated on has those bits set. Ex.:

01001010 XOR
11110100 is
10111110

Commands with an additional "var" suffix take gamevars rather than constants or defined labels for their inputs. As an alternate short form, "varvar" can be dropped from these commands; for example ife serves an an alias for ifvarvare.