Obj.in.box

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The obj.in.box command returns TRUE if the entire bottom row of pixels of the screen object is within a specified region.

Syntax

obj.in.box(obj oA, byt X1, byt Y1, byt X2, byt Y2)

Remarks

Test commands are only valid in an if statement.

The position test commands (posn, center.posn, right.posn, and obj.in.box are used to determine if a screen object's position is within a certain area.

The obj.in.box command checks for the entire baseline (bottom row of the current cel) of screen object oA to be within a bounded area, instead of just a single reference pixel, like the other position test commands.

The region to be tested is bounded by (X1, Y1) - (X2, Y2). The test returns TRUE if the entire baseline of screen object oA is >= X1 AND <= X2 AND >= Y1 AND <= Y2.

This test command can be combined with the NOT operator to test if an object is NOT in a specified region.

Possible Errors

AGI does not check that object number oA is a valid screen object. If it is not, the obj.in.box command will access invalid memory and the result of the test will be meaningless.

AGI expects the coordinates to be in upper-left to lower-right format. X1 must be less than or equal to X2 and Y1 must be less than or equal to Y2, or the test will always fail.

Example

Code:

<syntaxhighlight lang="agi"> if(obj.in.box(o1, 0, 120, 60, 130))

 { 
 print("the object's entire bottom row is in the box");
 }

</syntaxhighlight>

Technical Information

Required Interpreter Version: Available in all AGI versions.
Byte-Code Value: 16 (0x10 hex)

See Also

Test Commands
posn
right.posn
center.posn