CountCollisions ( entity )
Parameters
| entity - entity handle |
Description
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Returns how many collisions an entity was involved in during the last UpdateWorld. This is the gateway to the whole Collision family: loop the index from 1 to CountCollisions( entity ) and read each collision's details with CollisionEntity, CollisionX/Y/Z, CollisionNX/NY/NZ and CollisionTime. Both sides of a collision count it: the moving entity and the entity it hit each record one. A result of 0 simply means nothing touched the entity that step. The list is wiped and rebuilt by every UpdateWorld, so check it each frame after UpdateWorld - collision results do not accumulate across frames. See also: CollisionEntity, EntityCollided, CollisionX, CollisionNX, CollisionTime, UpdateWorld. |
Example
; CountCollisions Example ; ----------------------- Graphics3D 640,480,0,2 SetBuffer BackBuffer() ; Collision type ids type_player=1 type_scenery=2 ; NOTE: fixed overhead camera - the arrow keys steer the PLAYER, not the camera camera=CreateCamera() PositionEntity camera,0,13,-13 RotateEntity camera,45,0,0 light=CreateLight() RotateEntity light,60,30,0 floor=CreatePlane() EntityColor floor,70,110,70 ; The player ball is the collision SOURCE, so it needs an ellipsoid radius player=CreateSphere() EntityColor player,220,60,60 PositionEntity player,0,1,0 EntityRadius player,1 EntityType player,type_player ; Two walls meeting in a corner, plus a crate wall1=CreateCube() ScaleEntity wall1,7,1.5,0.5 PositionEntity wall1,0,1.5,7 EntityColor wall1,150,150,160 EntityType wall1,type_scenery wall2=CreateCube() ScaleEntity wall2,0.5,1.5,7 PositionEntity wall2,7,1.5,0 EntityColor wall2,150,150,160 EntityType wall2,type_scenery crate=CreateCube() ScaleEntity crate,1.2,1.2,1.2 PositionEntity crate,-4,1.2,3 EntityColor crate,200,160,60 EntityType crate,type_scenery ; Ellipsoid-to-polygon collisions with a sliding response Collisions type_player,type_scenery,2,2 While Not KeyDown(1) ; Arrow keys steer the player ball If KeyDown(200) Then MoveEntity player,0,0,0.1 If KeyDown(208) Then MoveEntity player,0,0,-0.1 If KeyDown(203) Then MoveEntity player,-0.1,0,0 If KeyDown(205) Then MoveEntity player,0.1,0,0 ; UpdateWorld performs the collision checks and the slide response UpdateWorld RenderWorld Text 0,0,"Arrow keys: drive the ball into the walls and crate Esc: exit" ; CountCollisions: how many contacts did the last UpdateWorld find? Text 0,20,"CountCollisions(player) = "+CountCollisions(player) Text 0,40,"Push into the corner where the two walls meet to score 2 at once" Flip Wend End
Index