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/**************************************************************************\
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* This file is part of the Coin 3D visualization library.
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* Copyright (C) 1998-2007 by Systems in Motion. All rights reserved.
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* ("GPL") version 2 as published by the Free Software Foundation.
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* See the file LICENSE.GPL at the root directory of this source
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* distribution for additional information about the GNU GPL.
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* For using Coin with software that can not be combined with the GNU
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* GPL, and for taking advantage of the additional benefits of our
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* support services, please contact Systems in Motion about acquiring
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* a Coin Professional Edition License.
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* See http://www.coin3d.org/ for more information.
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* Systems in Motion, Postboks 1283, Pirsenteret, 7462 Trondheim, NORWAY.
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* http://www.sim.no/ sales@sim.no coin-support@coin3d.org
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\**************************************************************************/
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\class SoFrustumCamera SoFrustumCamera.h Inventor/nodes/SoFrustumCamera.h
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\brief The SoFrustumCamera class defines a camera with a generic frustum..
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The SoFrustumCamera class makes it possible to specify a frustum in
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the same manner as the OpenGL glFrustum() function. It has four new
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fields (left, right, top, bottom), and will use
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SoCamera::nearDistance and SoCamera::farDistance for the two last
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glFrustum() parameters.
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This camera can be useful in applications that require full control
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over the view frustum, such as in CAVE or other multipipe
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\var SoSFFloat SoFrustumCamera::left
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The left clipping plane position. Default value is -0.5.
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\var SoSFFloat SoFrustumCamera::right
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The right clipping plane position. Default value is 0.5
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\var SoSFFloat SoFrustumCamera::bottom
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The bottom clipping plane position. Default value is -0.5.
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\var SoSFFloat SoFrustumCamera::top
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The top clipping plane position. Default value is 0.5.
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#include <Inventor/nodes/SoFrustumCamera.h>
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#include <Inventor/nodes/SoSubNodeP.h>
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#include <Inventor/errors/SoDebugError.h>
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#include <Inventor/SbSphere.h>
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SO_NODE_SOURCE(SoFrustumCamera);
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SoFrustumCamera::SoFrustumCamera(void)
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SO_NODE_INTERNAL_CONSTRUCTOR(SoFrustumCamera);
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SO_NODE_ADD_FIELD(top, (0.5f));
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SO_NODE_ADD_FIELD(bottom, (-0.5f));
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SO_NODE_ADD_FIELD(left, (-0.5f));
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SO_NODE_ADD_FIELD(right, (0.5f));
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SoFrustumCamera::~SoFrustumCamera(void)
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SoFrustumCamera::initClass(void)
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SO_NODE_INTERNAL_INIT_CLASS(SoFrustumCamera, SoNode::COIN_2_5);
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// Doc in superclass.
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SoFrustumCamera::scaleHeight(float scalefactor)
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this->top = this->top.getValue() * scalefactor;
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this->bottom = this->bottom.getValue() * scalefactor;
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// Doc in superclass.
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SoFrustumCamera::getViewVolume(float useaspectratio) const
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if (useaspectratio == 0.0f) { // LEAVE_ALONE viewportMapping
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vv.frustum(this->left.getValue(),
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this->right.getValue(),
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this->bottom.getValue(),
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this->top.getValue(),
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this->nearDistance.getValue(),
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this->farDistance.getValue());
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// calculate left and right based on height
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float cx = (this->left.getValue() + this->right.getValue()) * 0.5f;
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float h_2 = (this->top.getValue() - this->bottom.getValue()) * 0.5f;
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vv.frustum(cx - h_2 * useaspectratio,
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cx + h_2 * useaspectratio,
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this->bottom.getValue(),
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this->top.getValue(),
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this->nearDistance.getValue(),
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this->farDistance.getValue());
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vv.rotateCamera(this->orientation.getValue());
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vv.translateCamera(this->position.getValue());
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// Doc in superclass.
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SoFrustumCamera::viewBoundingBox(const SbBox3f & box, float aspect, float slack)
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// Only check for "flagged" emptiness, and don't use
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// SbBox3f::hasVolume(), as we *can* handle flat boxes.
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SoDebugError::postWarning("Frustum::viewBoundingBox",
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"bounding box is empty");
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// First, we want to move the camera in such a way that it is
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// pointing straight at the center of the scene bounding box -- but
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// without modifiying the rotation value (so we can't use
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// SoCamera::pointAt()).
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SbVec3f cameradirection;
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this->orientation.getValue().multVec(SbVec3f(0, 0, -1), cameradirection);
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this->position.setValue(box.getCenter() + -cameradirection);
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// Get the radius of the bounding sphere.
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bs.circumscribe(box);
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float radius = bs.getRadius();
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// Make sure that everything will still be inside the viewing volume
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// even if the aspect ratio "favorizes" width over height.
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float aspectradius = radius / (aspect < 1.0f ? aspect : 1.0f);
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// just calculate a heightangle so that we can reuse code from
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// SoPerspectiveCamera
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float nearv = this->nearDistance.getValue();
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SbVec3f tvec = SbVec3f(0.0f, this->top.getValue(), nearv);
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SbVec3f bvec = SbVec3f(0.0f, this->bottom.getValue(), nearv);
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(void) tvec.normalize();
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(void) bvec.normalize();
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float heightangle = (float) acos((double)SbClamp(tvec.dot(bvec), 0.0f, 1.0f));
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// Move the camera to the edge of the bounding sphere, while still
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// pointing at the scene.
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SbVec3f direction = this->position.getValue() - box.getCenter();
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direction.normalize();
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aspectradius + (aspectradius/float(atan(heightangle)));
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this->position.setValue(box.getCenter() + direction * movelength);
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// Set up the far clipping plane according to the slack value (a
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// value of 1.0 will yield a far clipping plane that is tangent to
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// the bounding sphere of the scene).
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float distance_to_midpoint =
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(this->position.getValue() - box.getCenter()).length();
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this->farDistance = distance_to_midpoint + radius * slack;
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// The focal distance is simply the distance from the camera to the
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// scene midpoint. This field is not used in rendering, its just
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// provided to make it easier for the user to do calculations based
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// on the distance between the camera and the scene.
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this->focalDistance = distance_to_midpoint;
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removed
src/nodes/SoFrustumCamera.cpp
