Left 4 Dead 2/Script Functions/TraceLine

Function Description

bool TraceLine(table traceTable)

Does a raycast along a line specified by two vectors, returning the first entity or geometry hit along the way. Script version of UTIL_TraceLine().

Parameters

Type	Name	Description
table	traceTable	Table used for both input and output.

Returns

bool - Whether the trace is successful. This only indicates that the trace was done, not whether it hit anything.

Example

traceTable <-
{
	start = Vector( 0,0,0 )
	end =  Vector( 0,0,256 )
}

if(TraceLine(traceTable))
{
	if(traceTable.hit)
	{
		printl("Trace hit!")
	}
	else
	{
		printl("Trace missed!")
	}
}
else
{
	printl("Trace failed!")
}

Input Parameters

Passed to the parameters table to set up the trace. The only required information to make the trace is providing the start and end point.

Type	Name	Description
Vector	start	Global vector where to start the trace.
Vector	end	Global vector where to end the trace.
int	mask	Optional collision type bitmask. Masks: TRACE_MASK_VISIBLE_AND_NPCS (default), TRACE_MASK_ALL, TRACE_MASK_VISION, TRACE_MASK_SHOT, TRACE_MASK_PLAYER_SOLID,
CBaseEntity	ignore	Optional entity to ignore when tracing.

Output parameters

Output written by the function to the parameters table.

Note: These parameters may not exist if the trace does not hit. Check that the key exists before using.

Type	Name	Description
Vector	pos	World space vector where the trace hit.
float	fraction	Fraction from the start to end where the trace hit.
bool	hit	Whether the trace hit something. Always present.
CBaseEntity	enthit	Handle of the entity the trace hit.
bool	startsolid	Whether the trace started inside something. Note: This parameter is not set if it is false