CameraCamerasarethedevicesthatcaptureanddisplaytheworldtotheplayer.ClearflagEachCamerastorescoloranddepthinformationwhenitrendersitsview.solidcolor.AnyemptyportionsofthescreenwilldisplaythecurrentCamera’sBackgroundColor.Skybox,BackgroundWithSolidColorselectedasyourClearFlagsproperty,youcanusetheBackgroundpropertytoselectacolorthatindicatesscreenareasremainingafterthegameelementshavedrawn.DepthWecancreatemultipleCameras.CamerasaredrawnfromlowDepthtohighDepth,withthelowestvaluebeingthebottom,renderedfirst.SeeEditor…..Forexample,aCamerawithaDepthof2willbedrawnontopofaCamerawithadepthof1.seeEditor….ViewportRect:seetheeditor…CullingMaskusedforselectivelyrenderinggroupsofobjectsusingLayers.Layersareusedtogroupobjects….Youmayonlywantacertainlayerofobjectstoberenderedbyonecamera,whileotherlayresarerenderedbyanother.CameraProjectioncamera

projectionsFieldofView(FOV)Theverticalviewingangleofthecamera,indegrees.ClippingplanesNote,onlyobjectsbetweentheclippingplanesthatfallwithinthevolumeofthefrustumwillberendered!!!ChangetheprojectionmatrixGetthecurrentcamera,Cameracam=GetComponent<Camera>();jectMatrix=mat;cam.ResetProjectMatrix();//updatescreenspace(pixelwidth,height)pixel(x,y)

(0,0)ViewportRectAtwo-dimensionalareaonthescreen,withanormalizedcoordinatescale.bottom-left:(0,0),top-right:(1,1),zisthedepthofthecamera.camera.rect=newRect();camera.pixelRect=newRect(x0,y0,w,h);Camera.pixelWidth,camera.pixelHeightReferenceforcameraFormoreadvancedpropertiesofacamera,clickonthebluebook….SeeDemoFirstpersonview,seetextbook…WritecodestoControlcamera….Camera類獲取或設(shè)置相機(jī)視口的寬高比PublicMatrix4x4cameraToWorldMatrix此屬性是返回相機(jī)的局部坐標(biāo)系到世界坐標(biāo)系的變換矩陣，只讀。NotethatcameraspacematchesOpenGLconvention:camera'sforwardisthenegativeZaxis.ThisisdifferentfromUnity'sconvention,whereforwardisthepositiveZaxis.PublicMatrix4x4worldToCameraMatrixMatrixthattransformsfromworldtocameraspace.Usethistocalculatethecameraspacepositionofobjectsortoprovidecustomcamera'slocationthatisnotbasedonthetransform.Ifyouchangethismatrix,thecameranolongerupdatesitsrenderingbasedonits

Transform.Thislastsuntilyoucall

ResetWorldToCameraMatrix.PublicMatrix4x4projectMatrixIfyouchangethismatrix,thecameranolongerupdatesitsrenderingbasedonitsfieldOfView.ThislastsuntilyoucallResetProjectionMatrix.PublicVector3ViewportToWorldPoint(Vector3pos);Transforms

position

fromviewportspaceintoworldspace.Viewportspaceisnormalizedandrelativetothecamera.Thebottom-leftoftheviewportis(0,0);thetop-rightis(1,1).Thezpositionisinworldunitsfromthecamera.PublicVector3WorldToViewportPoint(Vector3pos)Transforms

position

fromworldspaceintoviewportspace.Viewportspaceisnormalizedandrelativetothecamera.Thebottom-leftofthecamerais(0,0);thetop-rightis(1,1).Thezpositionisinworldunitsfromthecamera.PublicVector3WorldToScreenPoint(Vectr3pos)Transforms

position

fromworldspaceintoscreenspace.Screenspaceisdefinedinpixels.Thebottom-leftofthescreenis(0,0);theright-topis(pixelWidth,pixelHeight).Thezpositionisinworldunitsfromthecamera.PublicRayScreenPointToRay(Vector3pos)Returnsaraygoingfromcamerathroughascreenpoint.Resultingrayisinworldspace,startingonthenearplaneofthecameraandgoingthroughposition's(x,y)pixelcoordinatesonthescreen(position.zisignored).Screenspaceisdefinedinpixels.Thebottom-leftofthescreenis(0,0);theright-topis(pixelWidth

-1,pixelHeight

-1).PublicRayViewportPointToRay(Vector3pos)RayRay(Vector3origin,Vector3direction);Rayx=newRay(Vector3.zero,Vector3.right);RaycastAstaticfunctioninPhysics(組件).Castsaray,fromapoint,inadirection,oflength

maxDistance,againstallcolliders（組件，碰撞器）

inthescene.bool

TrueiftherayintersectswithaCollider,otherwisefalse.staticbool

Raycast(Ray

ray,float

maxDistance

=Mathf.Infinity…

staticbool

Raycast(Ray

ray,

out

RaycastHit

hitInfo,,float

maxDistance

=Mathf.Infinity,staticbool

Raycast(Vector3

origin,

Vector3

direction,out

RaycastHit

hitInfo,

float

maxDistance,

….RaycastHit

Structureusedtogetinformationbackfromaraycast.鼠標(biāo)拾取物體的原理

1、聲明一個(gè)觀察的攝像機(jī)、一個(gè)從攝像機(jī)原點(diǎn)出發(fā)的射線Ray以及一個(gè)用于檢測碰撞的RaycastHit；2、將射線Ray定義為從攝像機(jī)原點(diǎn)出發(fā)并且指向當(dāng)前鼠標(biāo)所在的坐標(biāo)(屏幕坐標(biāo))；3、定義碰撞RaycastHit為射線Ray與有碰撞屬性的物體的碰撞點(diǎn)。publicclasscamera:MonoBehaviour{publicCameraca;privateRayra;privateRaycastHithit;//UsethisforinitializationvoidStart(){}//UpdateiscalledonceperframevoidUpdate(){ra=ca