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Reference Guide
TGLOrthoCamera.cxx
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1// @(#)root/gl:$Id$
2// Author: Richard Maunder 25/05/2005
3
4/*************************************************************************
5 * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers. *
6 * All rights reserved. *
7 * *
8 * For the licensing terms see $ROOTSYS/LICENSE. *
9 * For the list of contributors see $ROOTSYS/README/CREDITS. *
10 *************************************************************************/
11
12#include "TMath.h"
13
14#include "TGLOrthoCamera.h"
15#include "TGLIncludes.h"
16#include "TGLUtil.h"
17
18
19/** \class TGLOrthoCamera
20\ingroup opengl
21Orthographic projection camera. Currently limited to three types
22defined at construction time - kXOY, kXOZ, kZOY - where this refers
23to the viewport plane axis - e.g. kXOY has X axis horizontal, Y
24vertical - i.e. looking down Z axis with Y vertical.
25
26The plane types restriction could easily be removed to supported
27arbitrary ortho projections along any axis/orientation with free
28rotations about them.
29*/
30
32
34
35////////////////////////////////////////////////////////////////////////////////
36/// Construct kXOY orthographic camera.
37
39 TGLCamera(TGLVector3( 0.0, 0.0, 1.0), TGLVector3(0.0, 1.0, 0.0)),
40 fType(kXOY),
41 fEnableRotate(kFALSE), fDollyToZoom(kTRUE),
42 fZoomMin(0.001), fZoomDefault(0.78), fZoomMax(1000.0),
43 fVolume(TGLVertex3(-100.0, -100.0, -100.0), TGLVertex3(100.0, 100.0, 100.0)),
44 fZoom(1.0)
45{
46 Setup(TGLBoundingBox(TGLVertex3(-100,-100,-100), TGLVertex3(100,100,100)));
47}
48
49////////////////////////////////////////////////////////////////////////////////
50/// Construct orthographic camera.
51
53 TGLCamera(hAxis, vAxis),
54 fType(type),
55 fEnableRotate(kFALSE), fDollyToZoom(kTRUE),
56 fZoomMin(0.001), fZoomDefault(0.78), fZoomMax(1000.0),
57 fVolume(TGLVertex3(-100.0, -100.0, -100.0), TGLVertex3(100.0, 100.0, 100.0)),
58 fZoom(1.0)
59{
60 Setup(TGLBoundingBox(TGLVertex3(-100,-100,-100), TGLVertex3(100,100,100)));
61}
62
63////////////////////////////////////////////////////////////////////////////////
64/// Destroy orthographic camera.
65
67{
68}
69
70////////////////////////////////////////////////////////////////////////////////
71/// Setup camera limits suitable to view the world volume defined by 'box'
72/// and call Reset() to initialise camera.
73
75{
76 fVolume = box;
77
79 {
80 if (fFixDefCenter)
81 {
83 }
84 else
85 {
86 TGLVertex3 center = box.Center();
87 SetCenterVec(center.X(), center.Y(), center.Z());
88 }
89 }
90 if (reset)
91 Reset();
92}
93
94////////////////////////////////////////////////////////////////////////////////
95/// Reset the camera to defaults - trucking, zooming to reframe the world volume
96/// established in Setup(). Note: limits defined in Setup() are not adjusted.
97
99{
101 switch (fType) {
102 case kXOY:
103 case kXnOY:
104 {
105 // X -> X, Y -> Y, Z -> Z
106 fDefXSize = e.X(); fDefYSize = e.Y();
107 break;
108 }
109 case kXOZ:
110 case kXnOZ:
111 {
112 // X -> X, Z -> Y, Y -> Z
113 fDefXSize = e.X(); fDefYSize = e.Z();
114 break;
115 }
116
117 case kZOY:
118 case kZnOY:
119 {
120 // Z -> X, Y -> Y, X -> Z
121 fDefXSize = e.Z(); fDefYSize = e.Y();
122 break;
123 }
124 case kZOX:
125 case kZnOX:
126 {
127 // Z -> X, X -> Y, Y -> Z
128 fDefXSize = e.Z(); fDefYSize = e.X();
129 break;
130 }
131 }
132
133 fDollyDefault = 1.25*0.5*TMath::Sqrt(3)*fVolume.Extents().Mag();
138 IncTimeStamp();
139}
140
141////////////////////////////////////////////////////////////////////////////////
142/// Dolly the camera.
143/// By default the dolly is reinterpreted to zoom, but it can be
144/// changed by modifying the fDollyToZoom data-member.
145
147{
148 if (fDollyToZoom) {
149 return Zoom(delta, mod1, mod2);
150 } else {
151 return TGLCamera::Dolly(delta, mod1, mod2);
152 }
153}
154
155////////////////////////////////////////////////////////////////////////////////
156/// Zoom the camera - 'adjust lens focal length, retaining camera position'.
157/// Arguments are:
158///
159/// - 'delta' - mouse viewport delta (pixels) - +ive zoom in, -ive zoom out
160/// - 'mod1' / 'mod2' - sensitivity modifiers - see TGLCamera::AdjustAndClampVal()
161///
162/// For an orthographic camera dollying and zooming are identical and both equate
163/// logically to a rescaling of the viewport limits - without center shift.
164/// There is no perspective foreshortening or lens 'focal length'.
165///
166/// Returns kTRUE is redraw required (camera change), kFALSE otherwise.
167
169{
170 if (AdjustAndClampVal(fZoom, fZoomMin, fZoomMax, -delta*2, fgZoomDeltaSens, mod1, mod2))
171 {
172 IncTimeStamp();
173 return kTRUE;
174 }
175 else
176 {
177 return kFALSE;
178 }
179}
180
181////////////////////////////////////////////////////////////////////////////////
182/// Set minimum zoom factor. If current zoom is less than z it is
183/// set to z.
184
186{
187 fZoomMin = z;
188 if (fZoom < fZoomMin) {
189 fZoom = fZoomMin;
190 IncTimeStamp();
191 }
192}
193
194////////////////////////////////////////////////////////////////////////////////
195/// Set maximum zoom factor. If current zoom is greater than z it
196/// is set to z.
197
199{
200 fZoomMax = z;
201 if (fZoom > fZoomMax) {
202 fZoom = fZoomMax;
203 IncTimeStamp();
204 }
205}
206
207////////////////////////////////////////////////////////////////////////////////
208/// Truck the camera - 'move camera parallel to film plane'.
209/// Returns kTRUE is redraw required (camera change), kFALSE otherwise.
210
212{
213 Double_t xstep = 2.0 * xDelta / fProjM[0] / fViewport.Width();
214 Double_t ystep = 2.0 * yDelta / fProjM[5] / fViewport.Height();
215
216 xstep = AdjustDelta(xstep, 1.0, mod1, mod2);
217 ystep = AdjustDelta(ystep, 1.0, mod1, mod2);
218
219 return Truck(-xstep, -ystep);
220}
221
222////////////////////////////////////////////////////////////////////////////////
223/// Rotate the camera - 'swivel round the view volume center'.
224/// Returns kTRUE is redraw required (camera change), kFALSE otherwise.
225
227{
228 if (fEnableRotate)
229 return TGLCamera::Rotate(xDelta, yDelta, mod1, mod2);
230 else
231 return kFALSE;
232}
233
234////////////////////////////////////////////////////////////////////////////////
235/// Apply the camera to the current GL context, setting the viewport, projection
236/// and modelview matrices. After this vertices etc can be directly entered
237/// in the world frame. This also updates the cached frustum values, enabling
238/// all the projection, overlap tests etc defined in TGLCamera to be used.
239///
240/// Arguments are:
241/// - 'box' - view volume box - ignored for ortho camera. Assumed to be same
242/// as one passed to Setup().
243/// - 'pickRect' - optional picking rect. If non-null, restrict drawing to this
244/// viewport rect.
245
247 const TGLRect * pickRect) const
248{
249 glViewport(fViewport.X(), fViewport.Y(), fViewport.Width(), fViewport.Height());
250
251 if(fViewport.Width() == 0 || fViewport.Height() == 0)
252 {
253 glMatrixMode(GL_PROJECTION);
254 glLoadIdentity();
255 glMatrixMode(GL_MODELVIEW);
256 glLoadIdentity();
257 return;
258 }
259
260 glMatrixMode(GL_PROJECTION);
261 glLoadIdentity();
262
263 // Load up any picking rect
264 if (pickRect)
265 {
266 TGLRect rect(*pickRect);
267 WindowToViewport(rect);
268 gluPickMatrix(rect.X(), rect.Y(), rect.Width(), rect.Height(),
269 (Int_t*) fViewport.CArr());
270 }
271
272 Double_t halfRangeX, halfRangeY;
274 halfRangeY = 0.5 *fDefYSize;
275 halfRangeX = halfRangeY*fViewport.Width()/fViewport.Height();
276 } else {
277 halfRangeX = 0.5 *fDefXSize;
278 halfRangeY = halfRangeX*fViewport.Height()/fViewport.Width();
279 }
280
281 halfRangeX /= fZoom;
282 halfRangeY /= fZoom;
283
286 glOrtho(-halfRangeX, halfRangeX,
287 -halfRangeY, halfRangeY,
289
290 if (!pickRect) glGetDoublev(GL_PROJECTION_MATRIX, fLastNoPickProjM.Arr());
291
292 // ii) setup modelview
293 glMatrixMode(GL_MODELVIEW);
294 glLoadIdentity();
296 TGLVector3 pos = mx.GetTranslation();
297 TGLVector3 fwd = mx.GetBaseVec(1);
298 TGLVector3 center = pos - fwd;
299 TGLVector3 up = mx.GetBaseVec(3);
300
301 gluLookAt(pos[0], pos[1], pos[2],
302 center[0], center[1], center[2],
303 up[0], up[1], up[2]);
304
306}
307
308////////////////////////////////////////////////////////////////////////////////
309/// Configure the camera state.
310/// - zoom - set directly (default = 0.78);
311/// - dolly - additional move along the camera forward direction;
312/// - center - new camera center (can be 0 for no change);
313/// - hRotate - additional "up/down" rotation in radians;
314/// - vRotate - additional "left/right" rotation in radians.
315
317 Double_t hRotate, Double_t vRotate)
318{
319 fZoom = zoom;
320
321 if (center)
322 SetCenterVec(center[0], center[1], center[2]);
323
324 fCamTrans.MoveLF(1, dolly);
325 RotateRad(hRotate, vRotate);
326
327 IncTimeStamp();
328}
#define e(i)
Definition: RSha256.hxx:103
int Int_t
Definition: RtypesCore.h:45
unsigned int UInt_t
Definition: RtypesCore.h:46
const Bool_t kFALSE
Definition: RtypesCore.h:101
bool Bool_t
Definition: RtypesCore.h:63
double Double_t
Definition: RtypesCore.h:59
const Bool_t kTRUE
Definition: RtypesCore.h:100
#define ClassImp(name)
Definition: Rtypes.h:364
int type
Definition: TGX11.cxx:121
Concrete class describing an orientated (free) or axis aligned box of 8 vertices.
TGLVector3 Extents() const
Abstract base camera class - concrete classes for orthographic and perspective cameras derive from it...
Definition: TGLCamera.h:44
TGLMatrix fLastNoPickProjM
timestamp
Definition: TGLCamera.h:97
virtual Bool_t RotateRad(Double_t hRotate, Double_t vRotate)
Rotate camera around center.
Definition: TGLCamera.cxx:927
Bool_t fCacheDirty
Definition: TGLCamera.h:95
virtual Bool_t Dolly(Int_t delta, Bool_t mod1, Bool_t mod2)
Dolly the camera - 'move camera along eye line, retaining lens focal length'.
Definition: TGLCamera.cxx:1046
TGLMatrix fCamBase
Definition: TGLCamera.h:76
void IncTimeStamp()
Definition: TGLCamera.h:124
Double_t fNearClip
current camera center
Definition: TGLCamera.h:86
TGLMatrix fCamTrans
Definition: TGLCamera.h:77
TGLMatrix fProjM
no-pick projection matrix (cached)
Definition: TGLCamera.h:98
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.
Definition: TGLCamera.cxx:722
virtual Bool_t Rotate(Int_t xDelta, Int_t yDelta, Bool_t mod1, Bool_t mod2)
Rotate the camera round view volume center established in Setup().
Definition: TGLCamera.cxx:916
TGLRect fViewport
frustum planes (cached)
Definition: TGLCamera.h:103
Double_t fDollyDefault
last applied far-clip
Definition: TGLCamera.h:90
void WindowToViewport(Int_t &, Int_t &y) const
Definition: TGLCamera.h:198
Double_t fDollyDistance
Definition: TGLCamera.h:91
void UpdateCache() const
largest box diagonal seen in OfInterest() - used when bootstrapping interest box
Definition: TGLCamera.cxx:108
Bool_t fExternalCenter
Definition: TGLCamera.h:78
Bool_t fFixDefCenter
Definition: TGLCamera.h:79
void SetCenterVec(Double_t x, Double_t y, Double_t z)
Set camera center vector.
Definition: TGLCamera.cxx:847
Double_t fFarClip
last applied near-clip
Definition: TGLCamera.h:87
Double_t AdjustDelta(Double_t screenShift, Double_t deltaFactor, Bool_t mod1, Bool_t mod2) const
Adjust a passed screen value and apply modifiers.
Definition: TGLCamera.cxx:762
TGLVector3 fFDCenter
Definition: TGLCamera.h:83
16 component (4x4) transform matrix - column MAJOR as per GL.
Definition: TGLUtil.h:598
void MoveLF(Int_t ai, Double_t amount)
Translate in local frame.
Definition: TGLUtil.cxx:813
void SetIdentity()
Set matrix to identity.
Definition: TGLUtil.cxx:765
Double_t * Arr()
Definition: TGLUtil.h:665
TGLVector3 GetBaseVec(Int_t b) const
Definition: TGLUtil.h:754
TGLVector3 GetTranslation() const
Return the translation component of matrix.
Definition: TGLUtil.cxx:794
Orthographic projection camera.
Double_t fDefYSize
virtual void Reset()
Reset the camera to defaults - trucking, zooming to reframe the world volume established in Setup().
void SetZoomMax(Double_t z)
Set maximum zoom factor.
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'.
Double_t fZoom
x, y size of scene from camera view
virtual Bool_t Dolly(Int_t delta, Bool_t mod1, Bool_t mod2)
Dolly the camera.
Double_t fZoomMax
virtual ~TGLOrthoCamera()
Destroy orthographic camera.
TGLBoundingBox fVolume
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...
Double_t fZoomMin
static UInt_t fgZoomDeltaSens
virtual Bool_t Zoom(Int_t delta, Bool_t mod1, Bool_t mod2)
Zoom the camera - 'adjust lens focal length, retaining camera position'.
virtual void Configure(Double_t zoom, Double_t dolly, Double_t center[3], Double_t hRotate, Double_t vRotate)
Configure the camera state.
TGLOrthoCamera()
Construct kXOY orthographic camera.
Double_t fDefXSize
scene volume
void SetZoomMin(Double_t z)
Set minimum zoom factor.
Double_t fZoomDefault
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.
Bool_t fEnableRotate
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'.
Viewport (pixel base) 2D rectangle class.
Definition: TGLUtil.h:422
Int_t Y() const
Definition: TGLUtil.h:448
const Int_t * CArr() const
Definition: TGLUtil.h:443
Int_t Height() const
Definition: TGLUtil.h:452
Int_t Width() const
Definition: TGLUtil.h:450
Int_t X() const
Definition: TGLUtil.h:446
3 component (x/y/z) vector class.
Definition: TGLUtil.h:248
Double_t Mag() const
Definition: TGLUtil.h:298
3 component (x/y/z) vertex class.
Definition: TGLUtil.h:84
Double_t X() const
Definition: TGLUtil.h:119
Double_t Z() const
Definition: TGLUtil.h:123
Double_t Y() const
Definition: TGLUtil.h:121
void box(Int_t pat, Double_t x1, Double_t y1, Double_t x2, Double_t y2)
Definition: fillpatterns.C:1
Double_t Sqrt(Double_t x)
Definition: TMath.h:641