mirror of
https://git.dev.opencascade.org/repos/occt.git
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bf02aa7d7d
- Use two different FBOs for accumulating frames for left/right eye projection. - Added equality checks to camera modification methods to avoid camera updates when performing identity operations.
1270 lines
43 KiB
C++
1270 lines
43 KiB
C++
// Created on: 2013-05-29
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// Created by: Anton POLETAEV
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// Copyright (c) 1999-2014 OPEN CASCADE SAS
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//
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// This file is part of Open CASCADE Technology software library.
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//
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// This library is free software; you can redistribute it and/or modify it under
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// the terms of the GNU Lesser General Public License version 2.1 as published
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// by the Free Software Foundation, with special exception defined in the file
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// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
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// distribution for complete text of the license and disclaimer of any warranty.
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//
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// Alternatively, this file may be used under the terms of Open CASCADE
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// commercial license or contractual agreement.
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#include <gp_Pln.hxx>
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#include <Standard_ShortReal.hxx>
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#include <Graphic3d_Camera.hxx>
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#include <Graphic3d_Vec4.hxx>
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#include <Graphic3d_WorldViewProjState.hxx>
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#include <Standard_Atomic.hxx>
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#include <Standard_Assert.hxx>
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#include <NCollection_Sequence.hxx>
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namespace
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{
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// (degrees -> radians) * 0.5
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static const Standard_Real DTR_HALF = 0.5 * 0.0174532925;
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// default property values
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static const Standard_Real DEFAULT_ZNEAR = 0.001;
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static const Standard_Real DEFAULT_ZFAR = 3000.0;
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// atomic state counter
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static volatile Standard_Integer THE_STATE_COUNTER = 0;
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// minimum camera distance
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static const Standard_Real MIN_DISTANCE = Pow (0.1, ShortRealDigits() - 2);
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// z-range tolerance compatible with for floating point.
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static Standard_Real zEpsilon()
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{
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return FLT_EPSILON;
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}
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// relative z-range tolerance compatible with for floating point.
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static Standard_Real zEpsilon (const Standard_Real theValue)
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{
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Standard_Real anAbsValue = Abs (theValue);
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if (anAbsValue <= (double)FLT_MIN)
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{
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return FLT_MIN;
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}
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Standard_Real aLogRadix = Log10 (anAbsValue) / Log10 (FLT_RADIX);
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Standard_Real aExp = Floor (aLogRadix);
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return FLT_EPSILON * Pow (FLT_RADIX, aExp);
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};
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};
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// =======================================================================
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// function : Graphic3d_Camera
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// purpose :
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// =======================================================================
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Graphic3d_Camera::Graphic3d_Camera()
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: myUp (0.0, 1.0, 0.0),
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myEye (0.0, 0.0, -1500.0),
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myCenter (0.0, 0.0, 0.0),
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myAxialScale (1.0, 1.0, 1.0),
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myProjType (Projection_Orthographic),
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myFOVy (45.0),
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myZNear (DEFAULT_ZNEAR),
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myZFar (DEFAULT_ZFAR),
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myAspect (1.0),
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myScale (1000.0),
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myZFocus (1.0),
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myZFocusType (FocusType_Relative),
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myIOD (0.05),
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myIODType (IODType_Relative)
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{
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myWorldViewProjState.Initialize ((Standard_Size)Standard_Atomic_Increment (&THE_STATE_COUNTER),
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(Standard_Size)Standard_Atomic_Increment (&THE_STATE_COUNTER),
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this);
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}
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// =======================================================================
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// function : Graphic3d_Camera
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// purpose :
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// =======================================================================
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Graphic3d_Camera::Graphic3d_Camera (const Handle(Graphic3d_Camera)& theOther)
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{
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myWorldViewProjState.Initialize (this);
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Copy (theOther);
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}
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// =======================================================================
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// function : CopyMappingData
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::CopyMappingData (const Handle(Graphic3d_Camera)& theOtherCamera)
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{
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SetFOVy (theOtherCamera->FOVy());
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SetZRange (theOtherCamera->ZNear(), theOtherCamera->ZFar());
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SetAspect (theOtherCamera->Aspect());
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SetScale (theOtherCamera->Scale());
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SetZFocus (theOtherCamera->ZFocusType(), theOtherCamera->ZFocus());
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SetIOD (theOtherCamera->GetIODType(), theOtherCamera->IOD());
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SetProjectionType (theOtherCamera->ProjectionType());
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}
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// =======================================================================
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// function : CopyOrientationData
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::CopyOrientationData (const Handle(Graphic3d_Camera)& theOtherCamera)
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{
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SetUp (theOtherCamera->Up());
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SetEye (theOtherCamera->Eye());
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SetCenter (theOtherCamera->Center());
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SetAxialScale (theOtherCamera->AxialScale());
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}
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// =======================================================================
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// function : Copy
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::Copy (const Handle(Graphic3d_Camera)& theOther)
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{
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CopyMappingData (theOther);
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CopyOrientationData (theOther);
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}
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// =======================================================================
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// function : SetEye
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::SetEye (const gp_Pnt& theEye)
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{
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if (Eye().IsEqual (theEye, 0.0))
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{
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return;
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}
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myEye = theEye;
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InvalidateOrientation();
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}
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// =======================================================================
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// function : SetCenter
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::SetCenter (const gp_Pnt& theCenter)
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{
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if (Center().IsEqual (theCenter, 0.0))
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{
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return;
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}
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myCenter = theCenter;
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InvalidateOrientation();
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}
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// =======================================================================
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// function : SetUp
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::SetUp (const gp_Dir& theUp)
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{
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if (Up().IsEqual (theUp, 0.0))
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{
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return;
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}
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myUp = theUp;
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InvalidateOrientation();
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}
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// =======================================================================
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// function : SetAxialScale
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::SetAxialScale (const gp_XYZ& theAxialScale)
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{
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if (AxialScale().IsEqual (theAxialScale, 0.0))
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{
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return;
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}
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myAxialScale = theAxialScale;
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InvalidateOrientation();
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}
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// =======================================================================
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// function : SetDistance
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::SetDistance (const Standard_Real theDistance)
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{
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if (Distance() == theDistance)
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{
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return;
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}
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gp_Vec aCenter2Eye (Direction());
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aCenter2Eye.Reverse();
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// Camera should have non-zero distance.
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aCenter2Eye.Scale (Max (theDistance, MIN_DISTANCE));
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SetEye (Center().Translated (aCenter2Eye));
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}
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// =======================================================================
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// function : Distance
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// purpose :
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// =======================================================================
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Standard_Real Graphic3d_Camera::Distance() const
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{
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return myEye.Distance (myCenter);
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}
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// =======================================================================
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// function : SetDirection
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::SetDirection (const gp_Dir& theDir)
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{
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if (Direction().IsEqual (theDir, 0.0))
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{
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return;
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}
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gp_Vec aScaledDir (theDir);
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aScaledDir.Scale (Distance());
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aScaledDir.Reverse();
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SetEye (Center().Translated (aScaledDir));
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}
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// =======================================================================
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// function : Direction
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// purpose :
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// =======================================================================
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gp_Dir Graphic3d_Camera::Direction() const
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{
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return gp_Dir (gp_Vec (myEye, myCenter));
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}
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// =======================================================================
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// function : SetScale
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::SetScale (const Standard_Real theScale)
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{
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if (Scale() == theScale)
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{
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return;
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}
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myScale = theScale;
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switch (myProjType)
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{
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case Projection_Perspective :
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case Projection_Stereo :
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case Projection_MonoLeftEye :
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case Projection_MonoRightEye :
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{
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Standard_Real aDistance = theScale * 0.5 / Tan(myFOVy * M_PI / 360.0);
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SetDistance (aDistance);
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}
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default :
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break;
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}
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InvalidateProjection();
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}
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// =======================================================================
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// function : Scale
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// purpose :
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// =======================================================================
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Standard_Real Graphic3d_Camera::Scale() const
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{
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switch (myProjType)
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{
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case Projection_Orthographic :
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return myScale;
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// case Projection_Perspective :
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// case Projection_Stereo :
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// case Projection_MonoLeftEye :
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// case Projection_MonoRightEye :
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default :
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return Distance() * 2.0 * Tan (myFOVy * M_PI / 360.0);
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}
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}
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// =======================================================================
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// function : SetProjectionType
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::SetProjectionType (const Projection theProjectionType)
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{
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Projection anOldType = ProjectionType();
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if (anOldType == theProjectionType)
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{
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return;
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}
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if (anOldType == Projection_Orthographic)
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{
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if (myZNear <= RealEpsilon())
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{
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myZNear = DEFAULT_ZNEAR;
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}
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if (myZFar <= RealEpsilon())
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{
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myZFar = DEFAULT_ZFAR;
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}
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}
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myProjType = theProjectionType;
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InvalidateProjection();
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}
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// =======================================================================
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// function : SetFOVy
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::SetFOVy (const Standard_Real theFOVy)
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{
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if (FOVy() == theFOVy)
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{
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return;
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}
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myFOVy = theFOVy;
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InvalidateProjection();
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}
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// =======================================================================
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// function : SetZRange
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::SetZRange (const Standard_Real theZNear,
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const Standard_Real theZFar)
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{
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Standard_ASSERT_RAISE (theZFar > theZNear, "ZFar should be greater than ZNear");
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if (!IsOrthographic())
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{
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Standard_ASSERT_RAISE (theZNear > 0.0, "Only positive Z-Near is allowed for perspective camera");
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Standard_ASSERT_RAISE (theZFar > 0.0, "Only positive Z-Far is allowed for perspective camera");
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}
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if (ZNear() == theZNear
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&& ZFar () == theZFar)
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{
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return;
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}
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myZNear = theZNear;
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myZFar = theZFar;
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InvalidateProjection();
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}
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// =======================================================================
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// function : SetAspect
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::SetAspect (const Standard_Real theAspect)
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{
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if (Aspect() == theAspect)
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{
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return;
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}
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myAspect = theAspect;
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InvalidateProjection();
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}
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// =======================================================================
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// function : SetZFocus
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::SetZFocus(const FocusType theType, const Standard_Real theZFocus)
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{
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if (ZFocusType() == theType
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&& ZFocus () == theZFocus)
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{
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return;
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}
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myZFocusType = theType;
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myZFocus = theZFocus;
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InvalidateProjection();
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}
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// =======================================================================
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// function : SetIOD
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::SetIOD (const IODType theType, const Standard_Real theIOD)
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{
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if (GetIODType() == theType
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&& IOD () == theIOD)
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{
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return;
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}
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myIODType = theType;
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myIOD = theIOD;
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InvalidateProjection();
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}
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// =======================================================================
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// function : OrthogonalizeUp
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::OrthogonalizeUp()
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{
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SetUp (OrthogonalizedUp());
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}
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// =======================================================================
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// function : OrthogonalizedUp
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// purpose :
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// =======================================================================
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gp_Dir Graphic3d_Camera::OrthogonalizedUp() const
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{
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gp_Dir aDir = Direction();
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gp_Dir aLeft = aDir.Crossed (Up());
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// recompute up as: up = left x direction
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return aLeft.Crossed (aDir);
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}
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// =======================================================================
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// function : Transform
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// purpose :
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// =======================================================================
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void Graphic3d_Camera::Transform (const gp_Trsf& theTrsf)
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{
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if (theTrsf.Form() == gp_Identity)
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{
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return;
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}
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SetUp (myUp.Transformed (theTrsf));
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SetEye (myEye.Transformed (theTrsf));
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SetCenter (myCenter.Transformed (theTrsf));
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}
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// =======================================================================
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// function : safePointCast
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// purpose :
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// =======================================================================
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static Graphic3d_Vec4d safePointCast (const gp_Pnt& thePnt)
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{
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Standard_Real aLim = 1e15f;
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// have to deal with values greater then max float
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gp_Pnt aSafePoint = thePnt;
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const Standard_Real aBigFloat = aLim * 0.1f;
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if (Abs (aSafePoint.X()) > aLim)
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aSafePoint.SetX (aSafePoint.X() >= 0 ? aBigFloat : -aBigFloat);
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if (Abs (aSafePoint.Y()) > aLim)
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aSafePoint.SetY (aSafePoint.Y() >= 0 ? aBigFloat : -aBigFloat);
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if (Abs (aSafePoint.Z()) > aLim)
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aSafePoint.SetZ (aSafePoint.Z() >= 0 ? aBigFloat : -aBigFloat);
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// convert point
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Graphic3d_Vec4d aPnt (aSafePoint.X(), aSafePoint.Y(), aSafePoint.Z(), 1.0);
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return aPnt;
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}
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// =======================================================================
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// function : Project
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// purpose :
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// =======================================================================
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gp_Pnt Graphic3d_Camera::Project (const gp_Pnt& thePnt) const
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{
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const Graphic3d_Mat4d& aViewMx = OrientationMatrix();
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const Graphic3d_Mat4d& aProjMx = ProjectionMatrix();
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// use compatible type of point
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Graphic3d_Vec4d aPnt = safePointCast (thePnt);
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aPnt = aViewMx * aPnt; // convert to view coordinate space
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aPnt = aProjMx * aPnt; // convert to projection coordinate space
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const Standard_Real aInvW = 1.0 / Standard_Real (aPnt.w());
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return gp_Pnt (aPnt.x() * aInvW, aPnt.y() * aInvW, aPnt.z() * aInvW);
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}
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// =======================================================================
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// function : UnProject
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// purpose :
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// =======================================================================
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gp_Pnt Graphic3d_Camera::UnProject (const gp_Pnt& thePnt) const
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{
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const Graphic3d_Mat4d& aViewMx = OrientationMatrix();
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const Graphic3d_Mat4d& aProjMx = ProjectionMatrix();
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Graphic3d_Mat4d aInvView;
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Graphic3d_Mat4d aInvProj;
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// this case should never happen
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if (!aViewMx.Inverted (aInvView) || !aProjMx.Inverted (aInvProj))
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{
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return gp_Pnt (0.0, 0.0, 0.0);
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}
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// use compatible type of point
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Graphic3d_Vec4d aPnt = safePointCast (thePnt);
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aPnt = aInvProj * aPnt; // convert to view coordinate space
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aPnt = aInvView * aPnt; // convert to world coordinate space
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const Standard_Real aInvW = 1.0 / Standard_Real (aPnt.w());
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return gp_Pnt (aPnt.x() * aInvW, aPnt.y() * aInvW, aPnt.z() * aInvW);
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}
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// =======================================================================
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// function : ConvertView2Proj
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// purpose :
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// =======================================================================
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gp_Pnt Graphic3d_Camera::ConvertView2Proj (const gp_Pnt& thePnt) const
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{
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const Graphic3d_Mat4d& aProjMx = ProjectionMatrix();
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// use compatible type of point
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Graphic3d_Vec4d aPnt = safePointCast (thePnt);
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aPnt = aProjMx * aPnt; // convert to projection coordinate space
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const Standard_Real aInvW = 1.0 / Standard_Real (aPnt.w());
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return gp_Pnt (aPnt.x() * aInvW, aPnt.y() * aInvW, aPnt.z() * aInvW);
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}
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// =======================================================================
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// function : ConvertProj2View
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// purpose :
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// =======================================================================
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gp_Pnt Graphic3d_Camera::ConvertProj2View (const gp_Pnt& thePnt) const
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{
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const Graphic3d_Mat4d& aProjMx = ProjectionMatrix();
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Graphic3d_Mat4d aInvProj;
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|
|
// this case should never happen, but...
|
|
if (!aProjMx.Inverted (aInvProj))
|
|
{
|
|
return gp_Pnt (0, 0, 0);
|
|
}
|
|
|
|
// use compatible type of point
|
|
Graphic3d_Vec4d aPnt = safePointCast (thePnt);
|
|
|
|
aPnt = aInvProj * aPnt; // convert to view coordinate space
|
|
|
|
const Standard_Real aInvW = 1.0 / Standard_Real (aPnt.w());
|
|
|
|
return gp_Pnt (aPnt.x() * aInvW, aPnt.y() * aInvW, aPnt.z() * aInvW);
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : ConvertWorld2View
|
|
// purpose :
|
|
// =======================================================================
|
|
gp_Pnt Graphic3d_Camera::ConvertWorld2View (const gp_Pnt& thePnt) const
|
|
{
|
|
const Graphic3d_Mat4d& aViewMx = OrientationMatrix();
|
|
|
|
// use compatible type of point
|
|
Graphic3d_Vec4d aPnt = safePointCast (thePnt);
|
|
|
|
aPnt = aViewMx * aPnt; // convert to view coordinate space
|
|
|
|
const Standard_Real aInvW = 1.0 / Standard_Real (aPnt.w());
|
|
|
|
return gp_Pnt (aPnt.x() * aInvW, aPnt.y() * aInvW, aPnt.z() * aInvW);
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : ConvertView2World
|
|
// purpose :
|
|
// =======================================================================
|
|
gp_Pnt Graphic3d_Camera::ConvertView2World (const gp_Pnt& thePnt) const
|
|
{
|
|
const Graphic3d_Mat4d& aViewMx = OrientationMatrix();
|
|
|
|
Graphic3d_Mat4d aInvView;
|
|
|
|
if (!aViewMx.Inverted (aInvView))
|
|
{
|
|
return gp_Pnt(0, 0, 0);
|
|
}
|
|
|
|
// use compatible type of point
|
|
Graphic3d_Vec4d aPnt = safePointCast (thePnt);
|
|
|
|
aPnt = aInvView * aPnt; // convert to world coordinate space
|
|
|
|
const Standard_Real aInvW = 1.0 / Standard_Real (aPnt.w());
|
|
|
|
return gp_Pnt (aPnt.x() * aInvW, aPnt.y() * aInvW, aPnt.z() * aInvW);
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : ViewDimensions
|
|
// purpose :
|
|
// =======================================================================
|
|
gp_XYZ Graphic3d_Camera::ViewDimensions() const
|
|
{
|
|
// view plane dimensions
|
|
Standard_Real aSize = IsOrthographic() ? myScale : (2.0 * Distance() * Tan (DTR_HALF * myFOVy));
|
|
Standard_Real aSizeX, aSizeY;
|
|
if (myAspect > 1.0)
|
|
{
|
|
aSizeX = aSize * myAspect;
|
|
aSizeY = aSize;
|
|
}
|
|
else
|
|
{
|
|
aSizeX = aSize;
|
|
aSizeY = aSize / myAspect;
|
|
}
|
|
|
|
// and frustum depth
|
|
return gp_XYZ (aSizeX, aSizeY, myZFar - myZNear);
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : Frustum
|
|
// purpose :
|
|
// =======================================================================
|
|
void Graphic3d_Camera::Frustum (gp_Pln& theLeft,
|
|
gp_Pln& theRight,
|
|
gp_Pln& theBottom,
|
|
gp_Pln& theTop,
|
|
gp_Pln& theNear,
|
|
gp_Pln& theFar) const
|
|
{
|
|
gp_Vec aProjection = gp_Vec (Direction());
|
|
gp_Vec anUp = OrthogonalizedUp();
|
|
gp_Vec aSide = aProjection ^ anUp;
|
|
|
|
Standard_ASSERT_RAISE (
|
|
!aProjection.IsParallel (anUp, Precision::Angular()),
|
|
"Can not derive SIDE = PROJ x UP - directions are parallel");
|
|
|
|
theNear = gp_Pln (Eye().Translated (aProjection * ZNear()), aProjection);
|
|
theFar = gp_Pln (Eye().Translated (aProjection * ZFar()), -aProjection);
|
|
|
|
Standard_Real aHScaleHor = Scale() * 0.5 * Aspect();
|
|
Standard_Real aHScaleVer = Scale() * 0.5;
|
|
|
|
gp_Pnt aPntLeft = Center().Translated (aHScaleHor * -aSide);
|
|
gp_Pnt aPntRight = Center().Translated (aHScaleHor * aSide);
|
|
gp_Pnt aPntBottom = Center().Translated (aHScaleVer * -anUp);
|
|
gp_Pnt aPntTop = Center().Translated (aHScaleVer * anUp);
|
|
|
|
gp_Vec aDirLeft = aSide;
|
|
gp_Vec aDirRight = -aSide;
|
|
gp_Vec aDirBottom = anUp;
|
|
gp_Vec aDirTop = -anUp;
|
|
if (!IsOrthographic())
|
|
{
|
|
Standard_Real aHFOVHor = ATan (Tan (DTR_HALF * FOVy()) * Aspect());
|
|
Standard_Real aHFOVVer = DTR_HALF * FOVy();
|
|
aDirLeft.Rotate (gp_Ax1 (gp::Origin(), anUp), aHFOVHor);
|
|
aDirRight.Rotate (gp_Ax1 (gp::Origin(), anUp), -aHFOVHor);
|
|
aDirBottom.Rotate (gp_Ax1 (gp::Origin(), aSide), -aHFOVVer);
|
|
aDirTop.Rotate (gp_Ax1 (gp::Origin(), aSide), aHFOVVer);
|
|
}
|
|
|
|
theLeft = gp_Pln (aPntLeft, aDirLeft);
|
|
theRight = gp_Pln (aPntRight, aDirRight);
|
|
theBottom = gp_Pln (aPntBottom, aDirBottom);
|
|
theTop = gp_Pln (aPntTop, aDirTop);
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : OrientationMatrix
|
|
// purpose :
|
|
// =======================================================================
|
|
const Graphic3d_Mat4d& Graphic3d_Camera::OrientationMatrix() const
|
|
{
|
|
return *UpdateOrientation (myMatricesD).Orientation;
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : OrientationMatrixF
|
|
// purpose :
|
|
// =======================================================================
|
|
const Graphic3d_Mat4& Graphic3d_Camera::OrientationMatrixF() const
|
|
{
|
|
return *UpdateOrientation (myMatricesF).Orientation;
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : ProjectionMatrix
|
|
// purpose :
|
|
// =======================================================================
|
|
const Graphic3d_Mat4d& Graphic3d_Camera::ProjectionMatrix() const
|
|
{
|
|
return *UpdateProjection (myMatricesD).MProjection;
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : ProjectionMatrixF
|
|
// purpose :
|
|
// =======================================================================
|
|
const Graphic3d_Mat4& Graphic3d_Camera::ProjectionMatrixF() const
|
|
{
|
|
return *UpdateProjection (myMatricesF).MProjection;
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : ProjectionStereoLeft
|
|
// purpose :
|
|
// =======================================================================
|
|
const Graphic3d_Mat4d& Graphic3d_Camera::ProjectionStereoLeft() const
|
|
{
|
|
return *UpdateProjection (myMatricesD).LProjection;
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : ProjectionStereoLeftF
|
|
// purpose :
|
|
// =======================================================================
|
|
const Graphic3d_Mat4& Graphic3d_Camera::ProjectionStereoLeftF() const
|
|
{
|
|
return *UpdateProjection (myMatricesF).LProjection;
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : ProjectionStereoRight
|
|
// purpose :
|
|
// =======================================================================
|
|
const Graphic3d_Mat4d& Graphic3d_Camera::ProjectionStereoRight() const
|
|
{
|
|
return *UpdateProjection (myMatricesD).RProjection;
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : ProjectionStereoRightF
|
|
// purpose :
|
|
// =======================================================================
|
|
const Graphic3d_Mat4& Graphic3d_Camera::ProjectionStereoRightF() const
|
|
{
|
|
return *UpdateProjection (myMatricesF).RProjection;
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : UpdateProjection
|
|
// purpose :
|
|
// =======================================================================
|
|
template <typename Elem_t>
|
|
Graphic3d_Camera::TransformMatrices<Elem_t>&
|
|
Graphic3d_Camera::UpdateProjection (TransformMatrices<Elem_t>& theMatrices) const
|
|
{
|
|
if (theMatrices.IsProjectionValid())
|
|
{
|
|
return theMatrices; // for inline accessors
|
|
}
|
|
|
|
theMatrices.InitProjection();
|
|
|
|
// sets top of frustum based on FOVy and near clipping plane
|
|
Elem_t aScale = static_cast<Elem_t> (myScale);
|
|
Elem_t aZNear = static_cast<Elem_t> (myZNear);
|
|
Elem_t aZFar = static_cast<Elem_t> (myZFar);
|
|
Elem_t anAspect = static_cast<Elem_t> (myAspect);
|
|
Elem_t aDXHalf = 0.0, aDYHalf = 0.0;
|
|
if (IsOrthographic())
|
|
{
|
|
aDXHalf = aScale * Elem_t (0.5);
|
|
aDYHalf = aScale * Elem_t (0.5);
|
|
}
|
|
else
|
|
{
|
|
aDXHalf = aZNear * Elem_t (Tan (DTR_HALF * myFOVy));
|
|
aDYHalf = aZNear * Elem_t (Tan (DTR_HALF * myFOVy));
|
|
}
|
|
|
|
if (anAspect > 1.0)
|
|
{
|
|
aDXHalf *= anAspect;
|
|
}
|
|
else
|
|
{
|
|
aDYHalf /= anAspect;
|
|
}
|
|
|
|
// sets right of frustum based on aspect ratio
|
|
Elem_t aLeft = -aDXHalf;
|
|
Elem_t aRight = aDXHalf;
|
|
Elem_t aBot = -aDYHalf;
|
|
Elem_t aTop = aDYHalf;
|
|
|
|
Elem_t aIOD = myIODType == IODType_Relative
|
|
? static_cast<Elem_t> (myIOD * Distance())
|
|
: static_cast<Elem_t> (myIOD);
|
|
|
|
Elem_t aFocus = myZFocusType == FocusType_Relative
|
|
? static_cast<Elem_t> (myZFocus * Distance())
|
|
: static_cast<Elem_t> (myZFocus);
|
|
|
|
switch (myProjType)
|
|
{
|
|
case Projection_Orthographic :
|
|
OrthoProj (aLeft, aRight, aBot, aTop, aZNear, aZFar, *theMatrices.MProjection);
|
|
break;
|
|
|
|
case Projection_Perspective :
|
|
PerspectiveProj (aLeft, aRight, aBot, aTop, aZNear, aZFar, *theMatrices.MProjection);
|
|
break;
|
|
|
|
case Projection_MonoLeftEye :
|
|
{
|
|
StereoEyeProj (aLeft, aRight, aBot, aTop,
|
|
aZNear, aZFar, aIOD, aFocus,
|
|
Standard_True, *theMatrices.MProjection);
|
|
*theMatrices.LProjection = *theMatrices.MProjection;
|
|
break;
|
|
}
|
|
|
|
case Projection_MonoRightEye :
|
|
{
|
|
StereoEyeProj (aLeft, aRight, aBot, aTop,
|
|
aZNear, aZFar, aIOD, aFocus,
|
|
Standard_False, *theMatrices.MProjection);
|
|
*theMatrices.RProjection = *theMatrices.MProjection;
|
|
break;
|
|
}
|
|
|
|
case Projection_Stereo :
|
|
{
|
|
PerspectiveProj (aLeft, aRight, aBot, aTop, aZNear, aZFar, *theMatrices.MProjection);
|
|
|
|
StereoEyeProj (aLeft, aRight, aBot, aTop,
|
|
aZNear, aZFar, aIOD, aFocus,
|
|
Standard_True,
|
|
*theMatrices.LProjection);
|
|
|
|
StereoEyeProj (aLeft, aRight, aBot, aTop,
|
|
aZNear, aZFar, aIOD, aFocus,
|
|
Standard_False,
|
|
*theMatrices.RProjection);
|
|
break;
|
|
}
|
|
}
|
|
|
|
return theMatrices; // for inline accessors
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : UpdateOrientation
|
|
// purpose :
|
|
// =======================================================================
|
|
template <typename Elem_t>
|
|
Graphic3d_Camera::TransformMatrices<Elem_t>&
|
|
Graphic3d_Camera::UpdateOrientation (TransformMatrices<Elem_t>& theMatrices) const
|
|
{
|
|
if (theMatrices.IsOrientationValid())
|
|
{
|
|
return theMatrices; // for inline accessors
|
|
}
|
|
|
|
theMatrices.InitOrientation();
|
|
|
|
NCollection_Vec3<Elem_t> anEye (static_cast<Elem_t> (myEye.X()),
|
|
static_cast<Elem_t> (myEye.Y()),
|
|
static_cast<Elem_t> (myEye.Z()));
|
|
|
|
NCollection_Vec3<Elem_t> aCenter (static_cast<Elem_t> (myCenter.X()),
|
|
static_cast<Elem_t> (myCenter.Y()),
|
|
static_cast<Elem_t> (myCenter.Z()));
|
|
|
|
NCollection_Vec3<Elem_t> anUp (static_cast<Elem_t> (myUp.X()),
|
|
static_cast<Elem_t> (myUp.Y()),
|
|
static_cast<Elem_t> (myUp.Z()));
|
|
|
|
NCollection_Vec3<Elem_t> anAxialScale (static_cast<Elem_t> (myAxialScale.X()),
|
|
static_cast<Elem_t> (myAxialScale.Y()),
|
|
static_cast<Elem_t> (myAxialScale.Z()));
|
|
|
|
LookOrientation (anEye, aCenter, anUp, anAxialScale, *theMatrices.Orientation);
|
|
|
|
return theMatrices; // for inline accessors
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : InvalidateProjection
|
|
// purpose :
|
|
// =======================================================================
|
|
void Graphic3d_Camera::InvalidateProjection()
|
|
{
|
|
myMatricesD.ResetProjection();
|
|
myMatricesF.ResetProjection();
|
|
myWorldViewProjState.ProjectionState() = (Standard_Size)Standard_Atomic_Increment (&THE_STATE_COUNTER);
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : InvalidateOrientation
|
|
// purpose :
|
|
// =======================================================================
|
|
void Graphic3d_Camera::InvalidateOrientation()
|
|
{
|
|
myMatricesD.ResetOrientation();
|
|
myMatricesF.ResetOrientation();
|
|
myWorldViewProjState.WorldViewState() = (Standard_Size)Standard_Atomic_Increment (&THE_STATE_COUNTER);
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : OrthoProj
|
|
// purpose :
|
|
// =======================================================================
|
|
template <typename Elem_t>
|
|
void Graphic3d_Camera::OrthoProj (const Elem_t theLeft,
|
|
const Elem_t theRight,
|
|
const Elem_t theBottom,
|
|
const Elem_t theTop,
|
|
const Elem_t theNear,
|
|
const Elem_t theFar,
|
|
NCollection_Mat4<Elem_t>& theOutMx)
|
|
{
|
|
// row 0
|
|
theOutMx.ChangeValue (0, 0) = Elem_t (2.0) / (theRight - theLeft);
|
|
theOutMx.ChangeValue (0, 1) = Elem_t (0.0);
|
|
theOutMx.ChangeValue (0, 2) = Elem_t (0.0);
|
|
theOutMx.ChangeValue (0, 3) = - (theRight + theLeft) / (theRight - theLeft);
|
|
|
|
// row 1
|
|
theOutMx.ChangeValue (1, 0) = Elem_t (0.0);
|
|
theOutMx.ChangeValue (1, 1) = Elem_t (2.0) / (theTop - theBottom);
|
|
theOutMx.ChangeValue (1, 2) = Elem_t (0.0);
|
|
theOutMx.ChangeValue (1, 3) = - (theTop + theBottom) / (theTop - theBottom);
|
|
|
|
// row 2
|
|
theOutMx.ChangeValue (2, 0) = Elem_t (0.0);
|
|
theOutMx.ChangeValue (2, 1) = Elem_t (0.0);
|
|
theOutMx.ChangeValue (2, 2) = Elem_t (-2.0) / (theFar - theNear);
|
|
theOutMx.ChangeValue (2, 3) = - (theFar + theNear) / (theFar - theNear);
|
|
|
|
// row 3
|
|
theOutMx.ChangeValue (3, 0) = Elem_t (0.0);
|
|
theOutMx.ChangeValue (3, 1) = Elem_t (0.0);
|
|
theOutMx.ChangeValue (3, 2) = Elem_t (0.0);
|
|
theOutMx.ChangeValue (3, 3) = Elem_t (1.0);
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : PerspectiveProj
|
|
// purpose :
|
|
// =======================================================================
|
|
template <typename Elem_t>
|
|
void Graphic3d_Camera::PerspectiveProj (const Elem_t theLeft,
|
|
const Elem_t theRight,
|
|
const Elem_t theBottom,
|
|
const Elem_t theTop,
|
|
const Elem_t theNear,
|
|
const Elem_t theFar,
|
|
NCollection_Mat4<Elem_t>& theOutMx)
|
|
{
|
|
// column 0
|
|
theOutMx.ChangeValue (0, 0) = (Elem_t (2.0) * theNear) / (theRight - theLeft);
|
|
theOutMx.ChangeValue (1, 0) = Elem_t (0.0);
|
|
theOutMx.ChangeValue (2, 0) = Elem_t (0.0);
|
|
theOutMx.ChangeValue (3, 0) = Elem_t (0.0);
|
|
|
|
// column 1
|
|
theOutMx.ChangeValue (0, 1) = Elem_t (0.0);
|
|
theOutMx.ChangeValue (1, 1) = (Elem_t (2.0) * theNear) / (theTop - theBottom);
|
|
theOutMx.ChangeValue (2, 1) = Elem_t (0.0);
|
|
theOutMx.ChangeValue (3, 1) = Elem_t (0.0);
|
|
|
|
// column 2
|
|
theOutMx.ChangeValue (0, 2) = (theRight + theLeft) / (theRight - theLeft);
|
|
theOutMx.ChangeValue (1, 2) = (theTop + theBottom) / (theTop - theBottom);
|
|
theOutMx.ChangeValue (2, 2) = -(theFar + theNear) / (theFar - theNear);
|
|
theOutMx.ChangeValue (3, 2) = Elem_t (-1.0);
|
|
|
|
// column 3
|
|
theOutMx.ChangeValue (0, 3) = Elem_t (0.0);
|
|
theOutMx.ChangeValue (1, 3) = Elem_t (0.0);
|
|
theOutMx.ChangeValue (2, 3) = -(Elem_t (2.0) * theFar * theNear) / (theFar - theNear);
|
|
theOutMx.ChangeValue (3, 3) = Elem_t (0.0);
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : StereoEyeProj
|
|
// purpose :
|
|
// =======================================================================
|
|
template <typename Elem_t>
|
|
void Graphic3d_Camera::StereoEyeProj (const Elem_t theLeft,
|
|
const Elem_t theRight,
|
|
const Elem_t theBottom,
|
|
const Elem_t theTop,
|
|
const Elem_t theNear,
|
|
const Elem_t theFar,
|
|
const Elem_t theIOD,
|
|
const Elem_t theZFocus,
|
|
const Standard_Boolean theIsLeft,
|
|
NCollection_Mat4<Elem_t>& theOutMx)
|
|
{
|
|
Elem_t aDx = theIsLeft ? Elem_t (0.5) * theIOD : Elem_t (-0.5) * theIOD;
|
|
Elem_t aDXStereoShift = aDx * theNear / theZFocus;
|
|
|
|
// construct eye projection matrix
|
|
PerspectiveProj (theLeft + aDXStereoShift,
|
|
theRight + aDXStereoShift,
|
|
theBottom, theTop, theNear, theFar,
|
|
theOutMx);
|
|
|
|
if (theIOD != Elem_t (0.0))
|
|
{
|
|
// X translation to cancel parallax
|
|
theOutMx.Translate (NCollection_Vec3<Elem_t> (aDx, Elem_t (0.0), Elem_t (0.0)));
|
|
}
|
|
}
|
|
|
|
// =======================================================================
|
|
// function : LookOrientation
|
|
// purpose :
|
|
// =======================================================================
|
|
template <typename Elem_t>
|
|
void Graphic3d_Camera::LookOrientation (const NCollection_Vec3<Elem_t>& theEye,
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const NCollection_Vec3<Elem_t>& theLookAt,
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const NCollection_Vec3<Elem_t>& theUpDir,
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const NCollection_Vec3<Elem_t>& theAxialScale,
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NCollection_Mat4<Elem_t>& theOutMx)
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{
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NCollection_Vec3<Elem_t> aForward = theLookAt - theEye;
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aForward.Normalize();
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// side = forward x up
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NCollection_Vec3<Elem_t> aSide = NCollection_Vec3<Elem_t>::Cross (aForward, theUpDir);
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aSide.Normalize();
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// recompute up as: up = side x forward
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NCollection_Vec3<Elem_t> anUp = NCollection_Vec3<Elem_t>::Cross (aSide, aForward);
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NCollection_Mat4<Elem_t> aLookMx;
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aLookMx.SetRow (0, aSide);
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aLookMx.SetRow (1, anUp);
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aLookMx.SetRow (2, -aForward);
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theOutMx.InitIdentity();
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theOutMx.Multiply (aLookMx);
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theOutMx.Translate (-theEye);
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NCollection_Mat4<Elem_t> anAxialScaleMx;
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anAxialScaleMx.ChangeValue (0, 0) = theAxialScale.x();
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anAxialScaleMx.ChangeValue (1, 1) = theAxialScale.y();
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anAxialScaleMx.ChangeValue (2, 2) = theAxialScale.z();
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theOutMx.Multiply (anAxialScaleMx);
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}
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//=============================================================================
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//function : ZFitAll
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//purpose :
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//=============================================================================
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bool Graphic3d_Camera::ZFitAll (const Standard_Real theScaleFactor,
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const Bnd_Box& theMinMax,
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const Bnd_Box& theGraphicBB,
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Standard_Real& theZNear,
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Standard_Real& theZFar) const
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{
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Standard_ASSERT_RAISE (theScaleFactor > 0.0, "Zero or negative scale factor is not allowed.");
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// Method changes zNear and zFar parameters of camera so as to fit graphical structures
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// by their graphical boundaries. It precisely fits min max boundaries of primary application
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// objects (second argument), while it can sacrifice the real graphical boundaries of the
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// scene with infinite or helper objects (third argument) for the sake of perspective projection.
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if (theGraphicBB.IsVoid())
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{
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theZNear = DEFAULT_ZNEAR;
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theZFar = DEFAULT_ZFAR;
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return false;
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}
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// Measure depth of boundary points from camera eye.
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NCollection_Sequence<gp_Pnt> aPntsToMeasure;
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Standard_Real aGraphicBB[6];
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theGraphicBB.Get (aGraphicBB[0], aGraphicBB[1], aGraphicBB[2], aGraphicBB[3], aGraphicBB[4], aGraphicBB[5]);
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aPntsToMeasure.Append (gp_Pnt (aGraphicBB[0], aGraphicBB[1], aGraphicBB[2]));
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aPntsToMeasure.Append (gp_Pnt (aGraphicBB[0], aGraphicBB[1], aGraphicBB[5]));
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aPntsToMeasure.Append (gp_Pnt (aGraphicBB[0], aGraphicBB[4], aGraphicBB[2]));
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aPntsToMeasure.Append (gp_Pnt (aGraphicBB[0], aGraphicBB[4], aGraphicBB[5]));
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aPntsToMeasure.Append (gp_Pnt (aGraphicBB[3], aGraphicBB[1], aGraphicBB[2]));
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aPntsToMeasure.Append (gp_Pnt (aGraphicBB[3], aGraphicBB[1], aGraphicBB[5]));
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aPntsToMeasure.Append (gp_Pnt (aGraphicBB[3], aGraphicBB[4], aGraphicBB[2]));
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aPntsToMeasure.Append (gp_Pnt (aGraphicBB[3], aGraphicBB[4], aGraphicBB[5]));
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Standard_Boolean isFiniteMinMax = !theMinMax.IsVoid() && !theMinMax.IsWhole();
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if (isFiniteMinMax)
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{
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Standard_Real aMinMax[6];
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theMinMax.Get (aMinMax[0], aMinMax[1], aMinMax[2], aMinMax[3], aMinMax[4], aMinMax[5]);
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aPntsToMeasure.Append (gp_Pnt (aMinMax[0], aMinMax[1], aMinMax[2]));
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aPntsToMeasure.Append (gp_Pnt (aMinMax[0], aMinMax[1], aMinMax[5]));
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aPntsToMeasure.Append (gp_Pnt (aMinMax[0], aMinMax[4], aMinMax[2]));
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aPntsToMeasure.Append (gp_Pnt (aMinMax[0], aMinMax[4], aMinMax[5]));
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aPntsToMeasure.Append (gp_Pnt (aMinMax[3], aMinMax[1], aMinMax[2]));
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aPntsToMeasure.Append (gp_Pnt (aMinMax[3], aMinMax[1], aMinMax[5]));
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aPntsToMeasure.Append (gp_Pnt (aMinMax[3], aMinMax[4], aMinMax[2]));
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aPntsToMeasure.Append (gp_Pnt (aMinMax[3], aMinMax[4], aMinMax[5]));
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}
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// Camera eye plane.
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gp_Dir aCamDir = Direction();
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gp_Pnt aCamEye = myEye;
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gp_Pln aCamPln (aCamEye, aCamDir);
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Standard_Real aModelMinDist = RealLast();
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Standard_Real aModelMaxDist = RealFirst();
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Standard_Real aGraphMinDist = RealLast();
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Standard_Real aGraphMaxDist = RealFirst();
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const gp_XYZ& anAxialScale = myAxialScale;
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// Get minimum and maximum distances to the eye plane.
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Standard_Integer aCounter = 0;
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NCollection_Sequence<gp_Pnt>::Iterator aPntIt(aPntsToMeasure);
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for (; aPntIt.More(); aPntIt.Next())
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{
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gp_Pnt aMeasurePnt = aPntIt.Value();
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aMeasurePnt = gp_Pnt (aMeasurePnt.X() * anAxialScale.X(),
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aMeasurePnt.Y() * anAxialScale.Y(),
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aMeasurePnt.Z() * anAxialScale.Z());
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Standard_Real aDistance = aCamPln.Distance (aMeasurePnt);
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// Check if the camera is intruded into the scene.
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if (aCamDir.IsOpposite (gp_Vec (aCamEye, aMeasurePnt), M_PI * 0.5))
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{
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aDistance *= -1;
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}
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// The first eight points are from theGraphicBB, the last eight points are from theMinMax (can be absent).
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Standard_Real& aChangeMinDist = aCounter >= 8 ? aModelMinDist : aGraphMinDist;
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Standard_Real& aChangeMaxDist = aCounter >= 8 ? aModelMaxDist : aGraphMaxDist;
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aChangeMinDist = Min (aDistance, aChangeMinDist);
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aChangeMaxDist = Max (aDistance, aChangeMaxDist);
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aCounter++;
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}
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// Compute depth of bounding box center.
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Standard_Real aMidDepth = (aGraphMinDist + aGraphMaxDist) * 0.5;
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Standard_Real aHalfDepth = (aGraphMaxDist - aGraphMinDist) * 0.5;
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// Compute enlarged or shrank near and far z ranges.
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Standard_Real aZNear = aMidDepth - aHalfDepth * theScaleFactor;
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Standard_Real aZFar = aMidDepth + aHalfDepth * theScaleFactor;
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if (!IsOrthographic())
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{
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// Everything is behind the perspective camera.
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if (aZFar < zEpsilon())
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{
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theZNear = DEFAULT_ZNEAR;
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theZFar = DEFAULT_ZFAR;
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return false;
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}
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}
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//
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// Consider clipping errors due to double to single precision floating-point conversion.
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//
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// Model to view transformation performs translation of points against eye position
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// in three dimensions. Both point coordinate and eye position values are converted from
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// double to single precision floating point numbers producing conversion errors.
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// Epsilon (Mod) * 3.0 should safely compensate precision error for z coordinate after
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// translation assuming that the:
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// Epsilon (Eye.Mod()) * 3.0 > Epsilon (Eye.X()) + Epsilon (Eye.Y()) + Epsilon (Eye.Z()).
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Standard_Real aEyeConf = 3.0 * zEpsilon (myEye.XYZ().Modulus());
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// Model to view transformation performs rotation of points according to view direction.
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// New z coordinate is computed as a multiplication of point's x, y, z coordinates by the
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// "forward" direction vector's x, y, z coordinates. Both point's and "z" direction vector's
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// values are converted from double to single precision floating point numbers producing
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// conversion errors.
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// Epsilon (Mod) * 6.0 should safely compensate the precision errors for the multiplication
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// of point coordinates by direction vector.
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gp_Pnt aGraphicMin = theGraphicBB.CornerMin();
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gp_Pnt aGraphicMax = theGraphicBB.CornerMax();
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Standard_Real aModelConf = 6.0 * zEpsilon (aGraphicMin.XYZ().Modulus()) +
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6.0 * zEpsilon (aGraphicMax.XYZ().Modulus());
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// Compensate floating point conversion errors by increasing zNear, zFar to avoid clipping.
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aZNear -= zEpsilon (aZNear) + aEyeConf + aModelConf;
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aZFar += zEpsilon (aZFar) + aEyeConf + aModelConf;
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if (!IsOrthographic())
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{
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// For perspective projection, the value of z in normalized device coordinates is non-linear
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// function of eye z coordinate. For fixed-point depth representation resolution of z in
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// model-view space will grow towards zFar plane and its scale depends mostly on how far is zNear
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// against camera's eye. The purpose of the code below is to select most appropriate zNear distance
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// to balance between clipping (less zNear, more chances to observe closely small models without clipping)
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// and resolution of depth. A well applicable criteria to this is a ratio between resolution of z at center
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// of model boundaries and the distance to that center point. The ratio is chosen empirically and validated
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// by tests database. It is considered to be ~0.001 (0.1%) for 24 bit depth buffer, for less depth bitness
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// the zNear will be placed similarly giving lower resolution.
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// Approximation of the formula for respectively large z range is:
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// zNear = [z * (1 + k) / (k * c)],
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// where:
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// z - distance to center of model boundaries;
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// k - chosen ratio, c - capacity of depth buffer;
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// k = 0.001, k * c = 1677.216, (1 + k) / (k * c) ~ 5.97E-4
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//
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// The function uses center of model boundaries computed from "theMinMax" boundaries (instead of using real
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// graphical boundaries of all displayed objects). That means that it can sacrifice resolution of presentation
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// of non primary ("infinite") application graphical objects in favor of better perspective projection of the
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// small applicative objects measured with "theMinMax" values.
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Standard_Real aZRange = isFiniteMinMax ? aModelMaxDist - aModelMinDist : aGraphMaxDist - aGraphMinDist;
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Standard_Real aZMin = isFiniteMinMax ? aModelMinDist : aGraphMinDist;
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Standard_Real aZ = aZMin < 0 ? aZRange / 2.0 : aZRange / 2.0 + aZMin;
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Standard_Real aZNearMin = aZ * 5.97E-4;
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if (aZNear < aZNearMin)
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{
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// Clip zNear according to the minimum value matching the quality.
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aZNear = aZNearMin;
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}
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else
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{
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// Compensate zNear conversion errors for perspective projection.
|
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aZNear -= aZFar * zEpsilon (aZNear) / (aZFar - zEpsilon (aZNear));
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}
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// Compensate zFar conversion errors for perspective projection.
|
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aZFar += zEpsilon (aZFar);
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// Ensure that after all the zNear is not a negative value.
|
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if (aZNear < zEpsilon())
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{
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aZNear = zEpsilon();
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}
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}
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theZNear = aZNear;
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theZFar = aZFar;
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return true;
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}
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