c_rotate

c_rotate(ENTITY* entity, ANGLE* angle, var mode)

Performs a collision detection of the given entity against its environment while rotating it by the given Euler angle. When using the OBB collision system and obstacles are nearby, use this function to rotate an entity rather than directly modifying its angles. Otherwise the entity could end up within another object on rotation.

Parameters:

entity	Entity to be rotated
angle	Rotation angle
mode	Collision and rotation mode, see below.

The following mode combinations are available:

IGNORE_YOU	ignores the you entity on collision detection.
IGNORE_PASSABLE	ignores all passable blocks and entities
IGNORE_PASSENTS	ignores passable model and sprite entities
IGNORE_WORLD	Ignores all level blocks and terrains.
IGNORE_MAPS	ignores all map entities.
IGNORE_MODELS	ignores all models.
IGNORE_SPRITES	ignores all sprites.
IGNORE_PUSH	ignores all entities with lower push values.
USE_AXIS USE_AXISR	does not rotate about world coordinates, but about the entities' coordinate system . USE_AXIS rotates the entity angle by the angle parameter (like ang_add), USE_AXISR rotates the angle parameter by the entity angle (like ang_rotate). This is required for rotating an arbitrarily orientated object, like an airplane or a spaceship, with collision detection. See ang_add for details.
USE_AABB	Use the old AABB rather than the new ellipsoid collision system. The AABB collision system does not require collision detection on rotation, so the entity is just rotated.

Returns:

>0 - Rotation successful.
0 - Entity was blocked by obstacles and could not be rotated.

Modifies:

entity.pan entity.tilt entity.roll	Angles of the entity
normal	Normal vector of hit polygon
bounce	Bounce vector of hit polygon
in_passable	1 if the rotation ended up in a passable block
in_solid	1 if the rotation ended up in a non passable block
event_type	Type of event

Remarks:

On collision, c_rotate can trigger collision events just like c_move.
For using relative rather than absolute rotation, use USE_AXIS or USE_AXISR. This however reduces the speed of the function.
If an entities' collision ellipsoid is symmetrical in x and y direction (like for most actors), performing collision detection on rotation about the pan axis is not necessary. Therefore, USE_AABB (or setting the pan angle directly) can be used to speed up the function.
Gliding along walls is always activated. Otherwise the entity could easily become stuck on rotation.
IGNORE_YOU can be used to prevent detection of a certain entity. !! A usual beginner's mistake is setting the IGNORE_YOU flag but not setting the you pointer. This causes the collision detection to fail randomly because you is modified by many functions (including this one).

Speed:

Fast if USE_AABB is set and USE_AXIS / USE_AXISR is not set; otherwise slow.

Example:

c_rotate (me, vector(time_step,0,0), IGNORE_YOU);