--- name: "lineIntersectsSurfaces" type: command status: ok groups: ["Math - Geometry"] arma3_since: "1.50" locality: {"argument": "global", "effect": null, "server_exec": false} source: https://community.bistudio.com/wiki/lineIntersectsSurfaces revid: 377700 updated: 2026-01-02T09:03:29Z --- # lineIntersectsSurfaces *Command · Math - Geometry · Arma 3 v1.50* Locality: arguments **global** ## Description Returns a list of intersections with surfaces and ground from *begPosASL* to *endPosASL*. Doesn't return intersection with sea surface. Works underwater, unlike [lineIntersects](../commands/lineIntersects.md). Hardcoded max distance: 5000m. > [!IMPORTANT] > - if *begPosASL* is under the ground and *endPosASL* is above it, the command will only return intersection with the ground, this is an engine limitation and none of the intersectXXX commands will work when initiated from under the ground. > - only a single LOD is checked for intersection. LOD2 will only be checked if LOD1 is unavailable. Since Arma 3 v2.20, there is an alternative syntax that does multiple checks in parallel, faster than multiple calls. ## Syntax ### Syntax 1 ```sqf lineIntersectsSurfaces [begPosASL, endPosASL, ignoreObj1, ignoreObj2, sortMode, maxResults, LOD1, LOD2, returnUnique] ``` **Parameters:** - `begPosASL`: [PositionASL](../topics/Position.md#positionasl) - virtual line start - `endPosASL`: [PositionASL](../topics/Position.md#positionasl) - virtual line end - `ignoreObj1`: [Object](../topics/Object.md) - (Optional, default [objNull](../commands/objNull.md)) first object to ignore - `ignoreObj2`: [Object](../topics/Object.md) - (Optional, default [objNull](../commands/objNull.md)) second object to ignore - `sortMode`: [Boolean](../topics/Boolean.md) - (Optional, default [true](../commands/true.md)) [true](../commands/true.md): closest to furthest, [false](../commands/false.md): furthest to closest - `maxResults`: [Number](../topics/Number.md) - (Optional, default 1) max results to return. -1 to return every result - `LOD1`: [String](../topics/String.md) - (Optional, default "VIEW") primary LOD to look for intersection. Can be one of: - "FIRE" - "VIEW" - "GEOM" - "IFIRE" - ("I" stands for Indirect, *almost* identical to "FIRE") - "NONE" - Arma 3 v2.02 "PHYSX" - PhysX geometry LOD - Arma 3 v2.08 "ROADWAY" - only works from the top *(since arma3 1.52)* - `LOD2`: [String](../topics/String.md) - (Optional, default "FIRE") secondary LOD to look for intersection. See *LOD1* for possible values *(since arma3 1.52)* - `returnUnique`: [Boolean](../topics/Boolean.md) - (Optional, default [true](../commands/true.md)) when [false](../commands/false.md), all intersections in the same object are included, otherwise only the first one *(since arma3 1.70)* **Returns:** [Array](../topics/Array.md) of [Array](../topics/Array.md)s with [intersectPosASL, surfaceNormal, intersectObj, parentObject, selectionNames, pathToBisurf] - intersectPosASL: [PositionASL](../topics/Position.md) - the actual position where line intersects surface - [surfaceNormal](../commands/surfaceNormal.md): [Vector](../topics/Vector3D.md) - a normal to the intersected surface - intersectObject: [Object](../topics/Object.md) - the object the surface belongs to (could be proxy object) - [objNull](../commands/objNull.md) if terrain - parentObject: [Object](../topics/Object.md) - the object proxy object belongs to (not always the same as intersect object) - [objNull](../commands/objNull.md) if terrain - Arma 3 v2.10 [selectionNames](../commands/selectionNames.md): [Array](../topics/Array.md) of [String](../topics/String.md)s - Names of the intersected selections (bones). Returns `[]` if there is no intersection with a selection. - Arma 3 v2.10 pathToBisurf: [String](../topics/String.md) - path to intersected surface properties (.bisurf) file. Returns `""` if surface has no special properties. Terrain surface properties begin with `1.`, and the surface properties are defined in `CfgSurfaces`. For example, if it returns `1. GdtVRsurface01`, properties are defined in: `configFile >> "CfgSurfaces" >> "GdtVRsurface01"` ### Syntax 2 *since arma3 2.20* ```sqf lineIntersectsSurfaces [[element1, element2, ...]] ``` **Parameters:** - `elementN`: [Array](../topics/Array.md) with [begPosASL, endPosASL, ignoreObj1, ignoreObj2, sortMode, maxResults, LOD1, LOD2, returnUnique] - begPosASL: [PositionASL](../topics/Position.md#positionasl) - virtual line start - endPosASL: [PositionASL](../topics/Position.md#positionasl) - virtual line end - ignoreObj1: [Object](../topics/Object.md) - (Optional, default [objNull](../commands/objNull.md)) first object to ignore - ignoreObj2: [Object](../topics/Object.md) - (Optional, default [objNull](../commands/objNull.md)) second object to ignore - sortMode: [Boolean](../topics/Boolean.md) - (Optional, default [true](../commands/true.md)) [true](../commands/true.md): closest to furthest, [false](../commands/false.md): furthest to closest - maxResults: [Number](../topics/Number.md) - (Optional, default 1) max results to return. -1 to return every result - LOD1: [String](../topics/String.md) - (Optional, default "VIEW") primary LOD to look for intersection. Can be one of: - "FIRE" - "VIEW" - "GEOM" - "IFIRE" - ("I" stands for Indirect, *almost* identical to "FIRE") - "NONE" - "PHYSX" - PhysX geometry LOD - "ROADWAY" - only works from the top - LOD2: [String](../topics/String.md) - (Optional, default "FIRE") secondary LOD to look for intersection. See *LOD1* for possible values - returnUnique: [Boolean](../topics/Boolean.md) - (Optional, default [true](../commands/true.md)) when [false](../commands/false.md), all intersections in the same object are included, otherwise only the first one **Returns:** [Array](../topics/Array.md) of [Array](../topics/Array.md)s with [intersectPosASL, surfaceNormal, intersectObj, parentObject, selectionNames, pathToBisurf] - intersectPosASL: [PositionASL](../topics/Position.md) - the actual position where line intersects surface - [surfaceNormal](../commands/surfaceNormal.md): [Vector](../topics/Vector3D.md) - a normal to the intersected surface - intersectObject: [Object](../topics/Object.md) - the object the surface belongs to (could be proxy object) - [objNull](../commands/objNull.md) if terrain - parentObject: [Object](../topics/Object.md) - the object proxy object belongs to (not always the same as intersect object) - [objNull](../commands/objNull.md) if terrain - [selectionNames](../commands/selectionNames.md): [Array](../topics/Array.md) of [String](../topics/String.md)s - Names of the intersected selections (bones). Returns `[]` if there is no intersection with a selection. - pathToBisurf: [String](../topics/String.md) - path to intersected surface properties (.bisurf) file. Returns `""` if surface has no special properties. Terrain surface properties begin with `1.`, and the surface properties are defined in `CfgSurfaces`. For example, if it returns `1. GdtVRsurface01`, properties are defined in: `configFile >> "CfgSurfaces" >> "GdtVRsurface01"` ## Examples ### Example 1 ```sqf _intersections = lineIntersectsSurfaces [eyePos player, aimPos chopper, player, chopper, true, -1]; ``` ### Example 2 ```sqf arrow = "Sign_Arrow_F" createVehicle [0,0,0]; onEachFrame { _ins = lineIntersectsSurfaces [ AGLToASL positionCameraToWorld [0,0,0], AGLToASL positionCameraToWorld [0,0,1000], player ]; if (count _ins == 0) exitWith { arrow setPosASL [0,0,0] }; arrow setPosASL (_ins select 0 select 0); arrow setVectorUp (_ins select 0 select 1); hintSilent str _ins; }; ``` ### Example 3 This should detect glass windows and wire fences (since Arma 3 v1.52): ```sqf wirefence = "Land_New_WiredFence_5m_F" createVehicle position player; arrow = "Sign_Arrow_F" createVehicle [0,0,0]; onEachFrame { _ins = lineIntersectsSurfaces [ AGLToASL positionCameraToWorld [0,0,0], AGLToASL positionCameraToWorld [0,0,1000], player, objNull, true, 1, "GEOM", "NONE" ]; if (count _ins == 0) exitWith { arrow setPosASL [0,0,0] }; arrow setPosASL (_ins select 0 select 0); arrow setVectorUp (_ins select 0 select 1); hintSilent str _ins; }; ``` ### Example 4 Alternative syntax to check intersections in parallel. Will draw a redline to the first intersecting object between the player and unit: ```sqf private _handle = addMissionEventHandler ["Draw3D", { private _enemies = units opfor; private _enemyDataArray = _enemies apply { [eyePos player, eyePos _x, player, _x] }; private _intersections = lineIntersectsSurfaces [_enemyDataArray]; { // No intersections found, draw green '+' icon at unit if (_x isEqualTo []) then { drawIcon3D [ "\a3\ui_f\data\gui\cfg\cursors\add_gs.paa", [0, 1, 0, 1], ASLToAGL (eyePos (_enemies#_forEachIndex)), 0.5, 0.5, 0, str (_enemies#_forEachIndex) ]; } else { private _firstIntersection = _x#0; // Draw red line and '+' icon to first intersecting object drawIcon3D [ "\a3\ui_f\data\gui\cfg\cursors\add_gs.paa", [1, 0, 0, 1], ASLToAGL (_firstIntersection#0), 0.5, 0.5, 0, str (_enemies#_forEachIndex) + "- Blocked by " + str (_firstIntersection#2) ]; drawLine3D [ ASLToAGL (eyePos player), ASLToAGL (_firstIntersection#0), [1, 0, 0, 1], 5 ]; }; } forEach _intersections; }]; ``` ## See also [lineIntersectsObjs](../commands/lineIntersectsObjs.md) · [lineIntersectsWith](../commands/lineIntersectsWith.md) · [lineIntersects](../commands/lineIntersects.md) · [terrainIntersectASL](../commands/terrainIntersectASL.md) · [terrainIntersectAtASL](../commands/terrainIntersectAtASL.md) · [terrainIntersect](../commands/terrainIntersect.md) · [intersect](../commands/intersect.md) · [cursorObject](../commands/cursorObject.md) · [cursorTarget](../commands/cursorTarget.md) · [checkVisibility](../commands/checkVisibility.md) ## Community notes **Killzone_Kid** — 2015-08-27 Fast check if the player is in a house: ```sqf KK_fnc_inHouse = { lineIntersectsSurfaces [ getPosWorld _this, getPosWorld _this vectorAdd [0, 0, 50], _this, objNull, true, 1, "GEOM", "NONE" ] select 0 params ["","","","_house"]; if (_house isKindOf "House") exitWith { true }; false }; onEachFrame { hintSilent str (player call KK_fnc_inHouse) }; ``` --- **Pierre MGI** — 2016-01-30 This command is useful to place weaponholder (and then spawned weapons) on floor of houses, correcting the spawn position (can_collide) to intersect with floor: ```sqf MGI_fnc_setPosAGLS = { params ["_obj", "_pos"]; _wh_pos = getPosASL _obj; _pos set [2, (ATLToASL _pos select 2) - 10]; _ins = lineIntersectsSurfaces [_wh_pos, _pos,_obj, objNull, true, 1, "VIEW", "FIRE"]; _surface_distance = if (count _ins > 0) then [{ (_ins select 0 select 0) distance _wh_pos }, { 0 }]; _wh_pos set [2, (getPosASL _obj select 2) - (_surface_distance)]; _weaponholder setPosASL _wh_pos; }; ``` After the position (_pos) obtained in BIS_fnc_buidingPositions array: ```sqf private _weaponHolder = createVehicle ["groundWeaponHolder", _pos, [], 0, "CAN_COLLIDE"]; [_weaponHolder, _pos] call MGI_fnc_setPosAGLS; ``` Then fill your weapon holder. --- **Tankbuster** — 2024-01-06 Note that dome_big and dome_small objects have glass roof panels which this function can't see if it intersects those windows Source: [BI Community Wiki — lineIntersectsSurfaces](https://community.bistudio.com/wiki/lineIntersectsSurfaces) (revision 377700).