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NAME

       SoOrthographicCamera -

       The SoOrthographicCamera class defines a camera node with orthographic
       rendering.

       Orthographic rendering will not give a particularly realistic
       impression of the scene, but non-realistic rendering is for various
       reasons widely used in applications for e.g. Computer Aided Design.

SYNOPSIS

       #include <Inventor/nodes/SoOrthographicCamera.h>

       Inherits SoCamera.

   Public Member Functions
       SoOrthographicCamera (void)
       virtual void scaleHeight (float scalefactor)
       virtual SbViewVolume getViewVolume (float useaspectratio=0.0f) const

   Static Public Member Functions
       static void initClass (void)

   Public Attributes
       SoSFFloat height

   Protected Member Functions
       virtual ~SoOrthographicCamera ()
       virtual void viewBoundingBox (const SbBox3f &box, float aspect, float
           slack)

Detailed Description

       The SoOrthographicCamera class defines a camera node with orthographic
       rendering.

       Orthographic rendering will not give a particularly realistic
       impression of the scene, but non-realistic rendering is for various
       reasons widely used in applications for e.g. Computer Aided Design.

       Also, a simple technique for drawing overlay / HUD style graphics
       (often appearing to be in 2D) can be implemented by setting up a ’sub
       scene graph’ with an SoOrthographicCamera and the geometry. As a simple
       demonstration of this concept, load this file into e.g. the
       ExaminerViewer:

         #Inventor V2.1 ascii

         Separator {
            PerspectiveCamera { position 0 0 5 }
            Cone { }

            Separator {
               OrthographicCamera {
                  position -0.75 -0.75 2
               }
               BaseColor { rgb 1 1 0 }
               Sphere { radius 0.2 }
            }
         }
         .fi

       You will likely encounter Z-buffer issues with this technique which makes the overlay / HUD graphics end up interspersed with the ’real’ geometry. If so, this can be solved by e.g. inserting an SoCallback node in the sub-scene, where you let the callback disable the depth buffer with glDisable(GL_DEPTH_TEST).

       FILE FORMAT/DEFAULTS:

           OrthographicCamera {
               viewportMapping ADJUST_CAMERA
               position 0 0 1
               orientation 0 0 1  0
               nearDistance 1
               farDistance 10
               aspectRatio 1
               focalDistance 5
               height 2
           }

Constructor & Destructor Documentation

   SoOrthographicCamera::SoOrthographicCamera (void) Constructor.
   SoOrthographicCamera::~SoOrthographicCamera () [protected, virtual]
       Destructor.

Member Function Documentation

   void SoOrthographicCamera::initClass (void) [static] Sets up initialization
       for data common to all instances of this class, like submitting
       necessary information to the Coin type system.
       Reimplemented from SoCamera.

   void SoOrthographicCamera::scaleHeight (float scalefactor) [virtual] Scale
       SoOrthographicCamera::height by multiplying with scalefactor.
       Implements SoCamera.

   SbViewVolume SoOrthographicCamera::getViewVolume (float useaspectratio =
       0.0f) const [virtual] Returns total view volume covered by the camera
       under the current settings.
       This view volume is not adjusted to account for viewport mapping. If
       you want the same view volume as the one used during rendering, you
       should do something like this:

         SbViewVolume vv;
         float aspectratio = myviewport.getViewportAspectRatio();

         switch (camera->viewportMapping.getValue()) {
         case SoCamera::CROP_VIEWPORT_FILL_FRAME:
         case SoCamera::CROP_VIEWPORT_LINE_FRAME:
         case SoCamera::CROP_VIEWPORT_NO_FRAME:
           vv = camera->getViewVolume(0.0f);
           break;
         case SoCamera::ADJUST_CAMERA:
           vv = camera->getViewVolume(aspectratio);
           if (aspectratio < 1.0f) vv.scale(1.0f / aspectratio);
           break;
         case SoCamera::LEAVE_ALONE:
           vv = camera->getViewVolume(0.0f);
           break;
         default:
           assert(0 && "unknown viewport mapping");
           break;
         }

         .fi

       Also, for the CROPPED viewport mappings, the viewport might be changed if the viewport aspect ratio is not equal to the camera aspect ratio. See SoCamera::getView() to see how this is done.

       Implements SoCamera.

   void SoOrthographicCamera::viewBoundingBox (const SbBox3f & box, float
       aspect, float slack) [protected, virtual] Convenience method for
       setting up the camera definition to cover the given bounding box with
       the given aspect ratio. Multiplies the exact dimensions with a slack
       factor to have some space between the rendered model and the borders of
       the rendering area.
       If you define your own camera node class, be aware that this method
       should not set the orientation field of the camera, only the position,
       focal distance and near and far clipping planes.

       Implements SoCamera.

Member Data Documentation

   SoSFFloat SoOrthographicCamera::height Height of viewport in world-space
       scale. Defaults to 2.0 units.

Author

       Generated automatically by Doxygen for Coin from the source code.