QueryPhysicsRay ( query,x#,y#,z#,dx#,dy#,dz#[,all_hits] )
Parameters
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query - query handle x# - world-space centre/origin X, in metres y# - world-space centre/origin Y, in metres z# - world-space centre/origin Z, in metres dx# - world X translation, end minus start dy# - world Y translation, end minus start dz# - world Z translation, end minus start all_hits (optional) - True for one nearest hit per eligible owning shape; False for only the closest hit (optional; 0) (default) |
Description
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Casts a ray from the supplied world origin and returns the hit count. The translation is end minus start, not an endpoint or velocity. It must be finite, non-zero and representable. all_hits=False returns the closest eligible hit; True returns the nearest intersection with each eligible owning shape, not every triangle, compound child, entry and exit within a shape. Results sort by increasing fraction, then wrapper shape handle, child and triangle indices. Native zero-fraction hits are ignored, matching the legacy closest-ray convention. Use an explicit overlap query to find starting intersections. Mesh/terrain shapes are triangle surfaces, not filled volumes. Queries use two-sided category/mask filtering in the existing 32-bit domain, plus optional ignored-body, sensor and target rules. Collision groups and joints do not override query masks. Disabled bodies are absent from world queries. Existing shape filters default to all category bits; assign explicit shape categories when separating groups. Results are copied. They survive StepPhysics and other queries until this query runs successfully again or is freed. Failed runs preserve the previous results. Freeing the owning world frees its queries. Invalid/stale/wrong-kind handles and invalid hit indices raise runtime errors. Requires Extended mode. See also: CreatePhysicsQuery, PhysicsQueryFilter, PhysicsQueryTarget, QueryPhysicsSphere, PhysicsQueryLimit. |
Example
; QueryPhysicsRay Example ; ----------------------- ; Requires Extended mode. Graphics3D 640,480,0,2 SetBuffer BackBuffer() Const PHYSICS_STATIC=0 Const PHYSICS_DYNAMIC=2 camera=CreateCamera() PositionEntity camera,0,7,-8 RotateEntity camera,40,0,0 light=CreateLight() RotateEntity light,45,-30,0 AmbientLight 60,60,60 ; An independent Box3D world with standard gravity world=CreatePhysicsWorld() ; Blue static floor ground=CreateCube() ScaleEntity ground,6,0.5,6 PositionEntity ground,0,-0.5,0 EntityColor ground,80,160,255 ground_body=CreatePhysicsBody(world,ground,PHYSICS_STATIC) ground_shape=PhysicsBodyBox(ground_body,12,1,12) ; A ring of crates to aim at For i=1 To 8 crate=CreateCube() ScaleEntity crate,0.5,0.5,0.5 PositionEntity crate,Cos(i*45)*4,0.5,Sin(i*45)*4 EntityColor crate,255,120,70 crate_body=CreatePhysicsBody(world,crate,PHYSICS_STATIC) crate_shape=PhysicsBodyBox(crate_body,1,1,1) Next ; A query object runs searches and keeps a copy of their results query=CreatePhysicsQuery(world) ; Start aimed at a crate angle#=45 While Not KeyDown(1) ; A and D sweep the ray around the centre If KeyDown(30) Then angle=angle+1.5 If KeyDown(32) Then angle=angle-1.5 dx#=Cos(angle)*6 dz#=Sin(angle)*6 StepPhysics world,1.0/60.0,4 ; Cast a ray 6 m out from the centre, half a metre above the floor hits=QueryPhysicsRay(query,0,0.5,0,dx,0,dz) ; Arrow keys move the camera If KeyDown(200) Then MoveEntity camera,0,0,0.1 If KeyDown(208) Then MoveEntity camera,0,0,-0.1 If KeyDown(203) Then TurnEntity camera,0,1,0 If KeyDown(205) Then TurnEntity camera,0,-1,0 RenderWorld ; Draw the ray from the centre to the first hit, or to its full length CameraProject camera,0,0.5,0 start_x=ProjectedX() start_y=ProjectedY() If hits>0 CameraProject camera,PhysicsQueryX(query,1),PhysicsQueryY(query,1),PhysicsQueryZ(query,1) Else CameraProject camera,dx,0.5,dz EndIf Line start_x,start_y,ProjectedX(),ProjectedY() Text 0,0,"Arrow keys: move camera A / D: sweep the ray Esc: exit" Text 0,20,"QueryPhysicsRay(query,0,0.5,0,"+dx+",0,"+dz+") = "+hits Text 0,40,"(1 when the ray hits a crate, 0 when it misses)" Flip Wend FreePhysicsWorld world End
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