ROOT
6.06/09
Reference Guide
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Orthographic projection camera.
Currently limited to three types defined at construction time - kXOY, kXOZ, kZOY - where this refers to the viewport plane axis - e.g. kXOY has X axis horizontal, Y vertical - i.e. looking down Z axis with Y vertical.
The plane types restriction could easily be removed to supported arbitrary ortho projections along any axis/orientation with free rotations about them.
Definition at line 35 of file TGLOrthoCamera.h.
Public Types | |
enum | EType { kZOY, kXOZ, kXOY, kZnOY, kXnOZ, kXnOY } |
Public Types inherited from TGLCamera | |
enum | EFrustumPlane { kNear = 0, kLeft = 1, kRight = 2, kTop = 3, kBottom = 4, kFar = 5, kPlanesPerFrustum = 6 } |
Public Types inherited from TObject | |
enum | EStatusBits { kCanDelete = BIT(0), kMustCleanup = BIT(3), kObjInCanvas = BIT(3), kIsReferenced = BIT(4), kHasUUID = BIT(5), kCannotPick = BIT(6), kNoContextMenu = BIT(8), kInvalidObject = BIT(13) } |
enum | { kIsOnHeap = 0x01000000, kNotDeleted = 0x02000000, kZombie = 0x04000000, kBitMask = 0x00ffffff } |
enum | { kSingleKey = BIT(0), kOverwrite = BIT(1), kWriteDelete = BIT(2) } |
Public Member Functions | |
TGLOrthoCamera () | |
TGLOrthoCamera (EType type, const TGLVector3 &hAxis, const TGLVector3 &vAxis) | |
Construct orthographic camera. More... | |
virtual | ~TGLOrthoCamera () |
Destroy orthographic camera. More... | |
virtual Bool_t | IsOrthographic () const |
virtual void | Setup (const TGLBoundingBox &box, Bool_t reset=kTRUE) |
Setup camera limits suitable to view the world volume defined by 'box' and call Reset() to initialise camera. More... | |
virtual void | Reset () |
Reset the camera to defaults - trucking, zooming to reframe the world volume established in Setup(). More... | |
virtual Bool_t | Dolly (Int_t delta, Bool_t mod1, Bool_t mod2) |
Dolly the camera. More... | |
virtual Bool_t | Zoom (Int_t delta, Bool_t mod1, Bool_t mod2) |
Zoom the camera - 'adjust lens focal length, retaining camera position'. More... | |
virtual Bool_t | Truck (Int_t xDelta, Int_t yDelta, Bool_t mod1, Bool_t mod2) |
Truck the camera - 'move camera parallel to film plane'. More... | |
virtual Bool_t | Rotate (Int_t xDelta, Int_t yDelta, Bool_t mod1, Bool_t mod2) |
Rotate the camera - 'swivel round the view volume center'. More... | |
virtual void | Apply (const TGLBoundingBox &sceneBox, const TGLRect *pickRect=0) const |
Apply the camera to the current GL context, setting the viewport, projection and modelview matrices. More... | |
virtual void | Configure (Double_t zoom, Double_t dolly, Double_t center[3], Double_t hRotate, Double_t vRotate) |
Configure the camera state. More... | |
void | SetEnableRotate (Bool_t x) |
Bool_t | GetEnableRotate () const |
Double_t | GetZoomMin () const |
Double_t | GetZoomMax () const |
void | SetZoomMin (Double_t z) |
Set minimum zoom factor. More... | |
void | SetZoomMax (Double_t z) |
Set maximum zoom factor. More... | |
void | SetZoomMinMax (Double_t min, Double_t max) |
void | SetDollyToZoom (Bool_t x) |
Bool_t | GetDollyToZoom () const |
void | SetZoom (Double_t x) |
Double_t | GetZoom () const |
Public Member Functions inherited from TGLCamera | |
TGLCamera () | |
Default base camera constructor. More... | |
TGLCamera (const TGLVector3 &hAxis, const TGLVector3 &vAxis) | |
Default base camera constructor. More... | |
virtual | ~TGLCamera () |
Base camera destructor. More... | |
virtual Bool_t | IsPerspective () const |
const TGLMatrix & | RefModelViewMatrix () const |
Bool_t | IsCacheDirty () const |
void | IncTimeStamp () |
UInt_t | TimeStamp () const |
void | SetViewport (const TGLRect &viewport) |
Set viewport extents from passed 'viewport' rect. More... | |
TGLRect & | RefViewport () |
const TGLRect & | RefViewport () const |
virtual Bool_t | Truck (Double_t xDelta, Double_t yDelta) |
Truck the camera - 'move camera parallel to film plane'. More... | |
virtual Bool_t | RotateRad (Double_t hRotate, Double_t vRotate) |
Rotate camera around center. More... | |
virtual Bool_t | RotateArcBall (Int_t xDelta, Int_t yDelta, Bool_t mod1, Bool_t mod2) |
Rotate the camera round view volume center established in Setup(). More... | |
virtual Bool_t | RotateArcBallRad (Double_t hRotate, Double_t vRotate) |
Rotate camera around center. More... | |
Bool_t | AdjustAndClampVal (Double_t &val, Double_t min, Double_t max, Int_t screenShift, Int_t screenShiftRange, Bool_t mod1, Bool_t mod2) const |
Adjust a passed REFERENCE value 'val', based on screenShift delta. More... | |
Double_t | AdjustDelta (Double_t screenShift, Double_t deltaFactor, Bool_t mod1, Bool_t mod2) const |
Adjust a passed screen value and apply modifiers. More... | |
void | SetExternalCenter (Bool_t x) |
Set camera center diffrent than scene center, if enable is kTRUE. More... | |
Bool_t | GetExternalCenter () |
void | SetCenterVec (Double_t x, Double_t y, Double_t z) |
Set camera center vector. More... | |
void | SetCenterVecWarp (Double_t x, Double_t y, Double_t z) |
Set camera center vector and do not keep the same combined camera transformation matrix. More... | |
Double_t * | GetCenterVec () |
void | SetFixDefCenter (Bool_t x) |
void | SetFixDefCenterVec (Double_t x, Double_t y, Double_t z) |
Double_t * | GetFixDefCenterVec () |
Double_t | GetNearClip () const |
Double_t | GetFarClip () const |
const TGLMatrix & | GetCamBase () const |
const TGLMatrix & | GetCamTrans () const |
TGLMatrix & | RefCamBase () |
TGLMatrix & | RefCamTrans () |
Double_t | GetTheta () const |
Get angle between camera up axis. More... | |
TGLMatrix & | RefLastNoPickProjM () const |
TGLVertex3 | EyePoint () const |
Return the camera eye point (vertex) in world space Camera must have valid frustum cache - call Apply() after last modification, before using. More... | |
TGLVector3 | EyeDirection () const |
Extract the camera eye direction (vector), running from EyePoint() Camera must have valid frustum cache - call Apply() after last modification, before using. More... | |
TGLVertex3 | FrustumCenter () const |
Find the center of the camera frustum from intersection of planes This method will work even with parallel left/right & top/bottom and infinite eye point of ortho cameras Camera must have valid frustum cache - call Apply() after last modification, before using. More... | |
const TGLPlane & | FrustumPlane (EFrustumPlane plane) const |
Rgl::EOverlap | FrustumOverlap (const TGLBoundingBox &box) const |
Calculate overlap (kInside, kOutside, kPartial) of box with camera frustum Camera must have valid frustum cache - call Apply() after last modification, before using. More... | |
Rgl::EOverlap | ViewportOverlap (const TGLBoundingBox &box) const |
Calculate overlap (kInside, kOutside, kPartial) of box projection onto viewport (as rect) against the viewport rect. More... | |
TGLRect | ViewportRect (const TGLBoundingBox &box, TGLBoundingBox::EFace face) const |
Calculate viewport rectangle which just contains projection of single 'face' of world frame bounding box 'box' onto the viewport. More... | |
TGLRect | ViewportRect (const TGLBoundingBox &box, const TGLBoundingBox::EFace *face=0) const |
Calculate viewport rectangle which just contains projection of world frame bounding box 'box' onto the viewport. More... | |
TGLVertex3 | WorldToViewport (const TGLVertex3 &worldVertex, TGLMatrix *modviewMat=0) const |
Convert a 3D world vertex to '3D' viewport (screen) one. More... | |
TGLVector3 | WorldDeltaToViewport (const TGLVertex3 &worldRef, const TGLVector3 &worldDelta) const |
Convert a 3D vector worldDelta (shift) about vertex worldRef to a viewport (screen) '3D' vector. More... | |
TGLVertex3 | ViewportToWorld (const TGLVertex3 &viewportVertex, TGLMatrix *modviewMat=0) const |
Convert a '3D' viewport vertex to 3D world one. More... | |
TGLLine3 | ViewportToWorld (Double_t viewportX, Double_t viewportY) const |
Convert a 2D viewport position to 3D world line - the projection of the viewport point into 3D space. More... | |
TGLLine3 | ViewportToWorld (const TPoint &viewport) const |
Convert a 2D viewport position to 3D world line - the projection of the viewport point into 3D space. More... | |
TGLVector3 | ViewportDeltaToWorld (const TGLVertex3 &worldRef, Double_t viewportXDelta, Double_t viewportYDelta, TGLMatrix *modviewMat=0) const |
Apply a 2D viewport delta (shift) to the projection of worldRef onto viewport, returning the resultant world vector which equates to it. More... | |
std::pair< Bool_t, TGLVertex3 > | ViewportPlaneIntersection (Double_t viewportX, Double_t viewportY, const TGLPlane &worldPlane) const |
Find the intersection of projection of supplied viewport point (a 3D world line - see ViewportToWorld) with supplied world plane. More... | |
std::pair< Bool_t, TGLVertex3 > | ViewportPlaneIntersection (const TPoint &viewport, const TGLPlane &worldPlane) const |
Find the intersection of projection of supplied viewport TPoint (a 3D world line - see ViewportToWorld) with supplied world plane. More... | |
void | WindowToViewport (Int_t &, Int_t &y) const |
void | WindowToViewport (TPoint &point) const |
void | WindowToViewport (TGLRect &rect) const |
void | WindowToViewport (TGLVertex3 &vertex) const |
Float_t | GetVAxisMinAngle () |
void | SetVAxisMinAngle (Float_t x) |
Bool_t | OfInterest (const TGLBoundingBox &box, Bool_t ignoreSize) const |
Calculate if the an object defined by world frame bounding box is 'of interest' to the camera. More... | |
Bool_t | UpdateInterest (Bool_t force) |
Update the internal interest box (fInterestBox) of the camera. More... | |
void | ResetInterest () |
Clear out the existing interest box. More... | |
void | DrawDebugAids () const |
Draw out some debugging aids for the camera: More... | |
ClassDef (TGLCamera, 1) | |
Public Member Functions inherited from TObject | |
TObject () | |
TObject (const TObject &object) | |
TObject copy ctor. More... | |
TObject & | operator= (const TObject &rhs) |
TObject assignment operator. More... | |
virtual | ~TObject () |
TObject destructor. More... | |
virtual void | AppendPad (Option_t *option="") |
Append graphics object to current pad. More... | |
virtual void | Browse (TBrowser *b) |
Browse object. May be overridden for another default action. More... | |
virtual const char * | ClassName () const |
Returns name of class to which the object belongs. More... | |
virtual void | Clear (Option_t *="") |
virtual TObject * | Clone (const char *newname="") const |
Make a clone of an object using the Streamer facility. More... | |
virtual Int_t | Compare (const TObject *obj) const |
Compare abstract method. More... | |
virtual void | Copy (TObject &object) const |
Copy this to obj. More... | |
virtual void | Delete (Option_t *option="") |
Delete this object. More... | |
virtual Int_t | DistancetoPrimitive (Int_t px, Int_t py) |
Computes distance from point (px,py) to the object. More... | |
virtual void | Draw (Option_t *option="") |
Default Draw method for all objects. More... | |
virtual void | DrawClass () const |
Draw class inheritance tree of the class to which this object belongs. More... | |
virtual TObject * | DrawClone (Option_t *option="") const |
Draw a clone of this object in the current pad. More... | |
virtual void | Dump () const |
Dump contents of object on stdout. More... | |
virtual void | Execute (const char *method, const char *params, Int_t *error=0) |
Execute method on this object with the given parameter string, e.g. More... | |
virtual void | Execute (TMethod *method, TObjArray *params, Int_t *error=0) |
Execute method on this object with parameters stored in the TObjArray. More... | |
virtual void | ExecuteEvent (Int_t event, Int_t px, Int_t py) |
Execute action corresponding to an event at (px,py). More... | |
virtual TObject * | FindObject (const char *name) const |
Must be redefined in derived classes. More... | |
virtual TObject * | FindObject (const TObject *obj) const |
Must be redefined in derived classes. More... | |
virtual Option_t * | GetDrawOption () const |
Get option used by the graphics system to draw this object. More... | |
virtual UInt_t | GetUniqueID () const |
Return the unique object id. More... | |
virtual const char * | GetName () const |
Returns name of object. More... | |
virtual const char * | GetIconName () const |
Returns mime type name of object. More... | |
virtual Option_t * | GetOption () const |
virtual char * | GetObjectInfo (Int_t px, Int_t py) const |
Returns string containing info about the object at position (px,py). More... | |
virtual const char * | GetTitle () const |
Returns title of object. More... | |
virtual Bool_t | HandleTimer (TTimer *timer) |
Execute action in response of a timer timing out. More... | |
virtual ULong_t | Hash () const |
Return hash value for this object. More... | |
virtual Bool_t | InheritsFrom (const char *classname) const |
Returns kTRUE if object inherits from class "classname". More... | |
virtual Bool_t | InheritsFrom (const TClass *cl) const |
Returns kTRUE if object inherits from TClass cl. More... | |
virtual void | Inspect () const |
Dump contents of this object in a graphics canvas. More... | |
virtual Bool_t | IsFolder () const |
Returns kTRUE in case object contains browsable objects (like containers or lists of other objects). More... | |
virtual Bool_t | IsEqual (const TObject *obj) const |
Default equal comparison (objects are equal if they have the same address in memory). More... | |
virtual Bool_t | IsSortable () const |
Bool_t | IsOnHeap () const |
Bool_t | IsZombie () const |
virtual Bool_t | Notify () |
This method must be overridden to handle object notification. More... | |
virtual void | ls (Option_t *option="") const |
The ls function lists the contents of a class on stdout. More... | |
virtual void | Paint (Option_t *option="") |
This method must be overridden if a class wants to paint itself. More... | |
virtual void | Pop () |
Pop on object drawn in a pad to the top of the display list. More... | |
virtual void | Print (Option_t *option="") const |
This method must be overridden when a class wants to print itself. More... | |
virtual Int_t | Read (const char *name) |
Read contents of object with specified name from the current directory. More... | |
virtual void | RecursiveRemove (TObject *obj) |
Recursively remove this object from a list. More... | |
virtual void | SaveAs (const char *filename="", Option_t *option="") const |
Save this object in the file specified by filename. More... | |
virtual void | SavePrimitive (std::ostream &out, Option_t *option="") |
Save a primitive as a C++ statement(s) on output stream "out". More... | |
virtual void | SetDrawOption (Option_t *option="") |
Set drawing option for object. More... | |
virtual void | SetUniqueID (UInt_t uid) |
Set the unique object id. More... | |
virtual void | UseCurrentStyle () |
Set current style settings in this object This function is called when either TCanvas::UseCurrentStyle or TROOT::ForceStyle have been invoked. More... | |
virtual Int_t | Write (const char *name=0, Int_t option=0, Int_t bufsize=0) |
Write this object to the current directory. More... | |
virtual Int_t | Write (const char *name=0, Int_t option=0, Int_t bufsize=0) const |
Write this object to the current directory. More... | |
void * | operator new (size_t sz) |
void * | operator new[] (size_t sz) |
void * | operator new (size_t sz, void *vp) |
void * | operator new[] (size_t sz, void *vp) |
void | operator delete (void *ptr) |
Operator delete. More... | |
void | operator delete[] (void *ptr) |
Operator delete []. More... | |
void | SetBit (UInt_t f, Bool_t set) |
Set or unset the user status bits as specified in f. More... | |
void | SetBit (UInt_t f) |
void | ResetBit (UInt_t f) |
Bool_t | TestBit (UInt_t f) const |
Int_t | TestBits (UInt_t f) const |
void | InvertBit (UInt_t f) |
virtual void | Info (const char *method, const char *msgfmt,...) const |
Issue info message. More... | |
virtual void | Warning (const char *method, const char *msgfmt,...) const |
Issue warning message. More... | |
virtual void | Error (const char *method, const char *msgfmt,...) const |
Issue error message. More... | |
virtual void | SysError (const char *method, const char *msgfmt,...) const |
Issue system error message. More... | |
virtual void | Fatal (const char *method, const char *msgfmt,...) const |
Issue fatal error message. More... | |
void | AbstractMethod (const char *method) const |
Use this method to implement an "abstract" method that you don't want to leave purely abstract. More... | |
void | MayNotUse (const char *method) const |
Use this method to signal that a method (defined in a base class) may not be called in a derived class (in principle against good design since a child class should not provide less functionality than its parent, however, sometimes it is necessary). More... | |
void | Obsolete (const char *method, const char *asOfVers, const char *removedFromVers) const |
Use this method to declare a method obsolete. More... | |
Private Attributes | |
EType | fType |
Bool_t | fEnableRotate |
Bool_t | fDollyToZoom |
Double_t | fZoomMin |
Double_t | fZoomDefault |
Double_t | fZoomMax |
TGLBoundingBox | fVolume |
Double_t | fDefXSize |
scene volume More... | |
Double_t | fDefYSize |
Double_t | fZoom |
x, y size of scene from camera view More... | |
Static Private Attributes | |
static UInt_t | fgZoomDeltaSens |
Additional Inherited Members | |
Static Public Member Functions inherited from TObject | |
static Long_t | GetDtorOnly () |
Return destructor only flag. More... | |
static void | SetDtorOnly (void *obj) |
Set destructor only flag. More... | |
static Bool_t | GetObjectStat () |
Get status of object stat flag. More... | |
static void | SetObjectStat (Bool_t stat) |
Turn on/off tracking of objects in the TObjectTable. More... | |
Protected Member Functions inherited from TGLCamera | |
void | UpdateCache () const |
largest box diagonal seen in OfInterest() - used when bootstrapping interest box More... | |
Protected Member Functions inherited from TObject | |
void | MakeZombie () |
virtual void | DoError (int level, const char *location, const char *fmt, va_list va) const |
Interface to ErrorHandler (protected). More... | |
Protected Attributes inherited from TGLCamera | |
TGLMatrix | fCamBase |
TGLMatrix | fCamTrans |
Bool_t | fExternalCenter |
Bool_t | fFixDefCenter |
Bool_t | fWasArcBalled |
TGLVector3 | fExtCenter |
TGLVector3 | fDefCenter |
TGLVector3 | fFDCenter |
TGLVector3 * | fCenter |
Double_t | fNearClip |
current camera center More... | |
Double_t | fFarClip |
last applied near-clip More... | |
Double_t | fDollyDefault |
last applied far-clip More... | |
Double_t | fDollyDistance |
Float_t | fVAxisMinAngle |
Bool_t | fCacheDirty |
UInt_t | fTimeStamp |
cached items dirty? More... | |
TGLMatrix | fLastNoPickProjM |
timestamp More... | |
TGLMatrix | fProjM |
no-pick projection matrix (cached) More... | |
TGLMatrix | fModVM |
projection matrix (cached) More... | |
TGLMatrix | fClipM |
modelView matrix (cached) More... | |
TGLPlane | fFrustumPlanes [kPlanesPerFrustum] |
object space clip matrix (cached) More... | |
TGLRect | fViewport |
frustum planes (cached) More... | |
TGLBoundingBox | fInterestBox |
viewport (GL coords - origin bottom left) More... | |
Double_t | fLargestSeen |
the interest box - created in UpdateInterest() More... | |
Static Protected Attributes inherited from TGLCamera | |
static UInt_t | fgDollyDeltaSens |
#include <TGLOrthoCamera.h>
Enumerator | |
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kZOY | |
kXOZ | |
kXOY | |
kZnOY | |
kXnOZ | |
kXnOY |
Definition at line 38 of file TGLOrthoCamera.h.
TGLOrthoCamera::TGLOrthoCamera | ( | ) |
TGLOrthoCamera::TGLOrthoCamera | ( | EType | type, |
const TGLVector3 & | hAxis, | ||
const TGLVector3 & | vAxis | ||
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Construct orthographic camera.
Definition at line 52 of file TGLOrthoCamera.cxx.
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Destroy orthographic camera.
Definition at line 66 of file TGLOrthoCamera.cxx.
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Apply the camera to the current GL context, setting the viewport, projection and modelview matrices.
After this vertices etc can be directly entered in the world frame. This also updates the cached frustum values, enabling all the projection, overlap tests etc defined in TGLCamera to be used.
Arguments are:
Implements TGLCamera.
Definition at line 239 of file TGLOrthoCamera.cxx.
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Configure the camera state.
Implements TGLCamera.
Definition at line 309 of file TGLOrthoCamera.cxx.
Referenced by TEveLegoEventHandler::Rotate(), and TGLViewer::SetOrthoCamera().
Dolly the camera.
By default the dolly is reinterpreted to zoom, but it can be changed by modifying the fDollyToZoom data-member.
Reimplemented from TGLCamera.
Definition at line 139 of file TGLOrthoCamera.cxx.
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Definition at line 90 of file TGLOrthoCamera.h.
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Definition at line 81 of file TGLOrthoCamera.h.
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Definition at line 93 of file TGLOrthoCamera.h.
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Definition at line 84 of file TGLOrthoCamera.h.
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Definition at line 83 of file TGLOrthoCamera.h.
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Reimplemented from TGLCamera.
Definition at line 63 of file TGLOrthoCamera.h.
Rotate the camera - 'swivel round the view volume center'.
Returns kTRUE is redraw required (camera change), kFALSE otherwise.
Reimplemented from TGLCamera.
Definition at line 219 of file TGLOrthoCamera.cxx.
Definition at line 89 of file TGLOrthoCamera.h.
Referenced by TGLSAViewer::ToggleOrthoDolly().
Definition at line 80 of file TGLOrthoCamera.h.
Referenced by TGLSAViewer::ToggleOrthoRotate().
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Setup camera limits suitable to view the world volume defined by 'box' and call Reset() to initialise camera.
Implements TGLCamera.
Definition at line 74 of file TGLOrthoCamera.cxx.
Referenced by TEveLegoEventHandler::Rotate(), TGLViewer::SetupCameras(), and TGLOrthoCamera().
Definition at line 92 of file TGLOrthoCamera.h.
Set maximum zoom factor.
If current zoom is greater than z it is set to z.
Definition at line 191 of file TGLOrthoCamera.cxx.
Referenced by SetZoomMinMax().
Set minimum zoom factor.
If current zoom is less than z it is set to z.
Definition at line 178 of file TGLOrthoCamera.cxx.
Referenced by SetZoomMinMax().
Definition at line 87 of file TGLOrthoCamera.h.
Truck the camera - 'move camera parallel to film plane'.
Returns kTRUE is redraw required (camera change), kFALSE otherwise.
Implements TGLCamera.
Definition at line 204 of file TGLOrthoCamera.cxx.
Referenced by TEveLegoEventHandler::Rotate().
Zoom the camera - 'adjust lens focal length, retaining camera position'.
Arguments are:
For an orthographic camera dollying and zooming are identical and both equate logically to a rescaling of the viewport limits - without center shift. There is no perspective foreshortening or lens 'focal length'.
Returns kTRUE is redraw required (camera change), kFALSE otherwise.
Implements TGLCamera.
Definition at line 161 of file TGLOrthoCamera.cxx.
Referenced by Dolly().
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Definition at line 53 of file TGLOrthoCamera.h.
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Definition at line 44 of file TGLOrthoCamera.h.
Referenced by Dolly(), and GetDollyToZoom().
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Definition at line 43 of file TGLOrthoCamera.h.
Referenced by GetEnableRotate(), and Rotate().
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staticprivate |
Definition at line 56 of file TGLOrthoCamera.h.
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Definition at line 42 of file TGLOrthoCamera.h.
Referenced by Reset().
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Definition at line 50 of file TGLOrthoCamera.h.
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x, y size of scene from camera view
Definition at line 54 of file TGLOrthoCamera.h.
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Definition at line 48 of file TGLOrthoCamera.h.
Referenced by Reset().
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Definition at line 49 of file TGLOrthoCamera.h.
Referenced by GetZoomMax(), and SetZoomMax().
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Definition at line 47 of file TGLOrthoCamera.h.
Referenced by GetZoomMin(), and SetZoomMin().