SbViewportRegion(3)

💅 SbViewportRegion — from the Coin manual (section 3) ✨

okay bestie, sit down, hydrate, because we're about to talk about SbViewportRegion and it's genuinely so much cuter than it sounds 🎀

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🌸 NAME 🌸

SbViewportRegion — the class that's literally just a viewport within a full window. that's it. that's the whole vibe. it's giving "small rectangle, big feelings" 💖

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✨ SYNOPSIS ✨

#include <Inventor/SbViewportRegion.h>

🫶 Public Member Functions 🫶

SbViewportRegion (void)
SbViewportRegion (short width, short height)
SbViewportRegion (SbVec2s winSize)
SbViewportRegion (const SbViewportRegion &vpReg)
void setWindowSize (short width, short height)
void setWindowSize (SbVec2s winSize)
void setViewport (float left, float bottom, float width, float height)
void setViewport (SbVec2f origin, SbVec2f size)
void setViewportPixels (short left, short bottom, short width, short
    height)
void setViewportPixels (SbVec2s origin, SbVec2s size)
const SbVec2s & getWindowSize (void) const
const SbVec2f & getViewportOrigin (void) const
const SbVec2s & getViewportOriginPixels (void) const
const SbVec2f & getViewportSize (void) const
const SbVec2s & getViewportSizePixels (void) const
float getViewportAspectRatio (void) const
void scaleWidth (float ratio)
void scaleHeight (float ratio)
void setPixelsPerInch (float ppi)
float getPixelsPerInch (void) const
float getPixelsPerPoint (void) const
void print (FILE *file) const

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🦋 Detailed Description 🦋

okay so. SbViewportRegion is a viewport within a full window. periodt.

The SbViewportRegion class contains information to represent a subview within a window. It stores information about the origin and size of the subview, as well as the size of the underlying "full" window. so like, it knows where the little window-in-the-window lives and how big the whole window is. main character energy tbh 👑

Available methods include inquiries and manipulation in both normalized coordinates and pixel coordinates. two flavors, both iconic 💅

Below is a small example showing how the viewport of a viewer class can be modified, within a "proper" Coin and window system context. Hit 'D' or 'U' to move the viewport region 40 pixels down or up, respectively. Click 'Esc' and zoom with left + middle mouse buttons, to see how the region is defined, where no 3D geometry will be visible outside it. Click 'Esc' again to use 'U' and 'D'.

// Copyright (C) by Kongsberg Oil & Gas Technologies. All rights reserved.

#include <Inventor/Qt/SoQt.h>
#include <Inventor/Qt/viewers/SoQtExaminerViewer.h>
#include <Inventor/nodes/SoEventCallback.h>
#include <Inventor/nodes/SoSeparator.h>
#include <Inventor/nodes/SoCone.h>
#include <Inventor/events/SoKeyboardEvent.h>

// ************************************************************

static void
keypresscbfunc(void * userdata, SoEventCallback * keyboardcb)
{
  SoQtExaminerViewer * viewer = (SoQtExaminerViewer *)userdata;

  const SoEvent * event = keyboardcb->getEvent();

  int shift = 0;

  if (SO_KEY_PRESS_EVENT(event, U)) {
    shift = 40;
    keyboardcb->setHandled();
  }
  else if (SO_KEY_PRESS_EVENT(event, D)) {
    shift = -40;
    keyboardcb->setHandled();
  }

  if (keyboardcb->isHandled()) {
    SbViewportRegion vpr = viewer->getViewportRegion();
    SbVec2s size = vpr.getViewportSizePixels();
    SbVec2s origin = vpr.getViewportOriginPixels();
    origin[1] -= shift;
    vpr.setViewportPixels(origin, size);
    viewer->setViewportRegion(vpr);
  }
}

// ************************************************************

int
main(int argc, char ** argv)
{
  QWidget * window = SoQt::init(argv[0]);

  SoSeparator * root = new SoSeparator;
  root->ref();

  root->addChild(new SoCone);

  SoQtExaminerViewer * viewer = new SoQtExaminerViewer(window);

  SoEventCallback * eventcb = new SoEventCallback;
  eventcb->addEventCallback(SoKeyboardEvent::getClassTypeId(),
                            keypresscbfunc, viewer);
  root->insertChild(eventcb, 0);

  viewer->setViewing(FALSE);
  viewer->setDecoration(FALSE);
  viewer->setSceneGraph(root);
  viewer->show();
  SoQt::show(window);

  SoQt::mainLoop();

  delete viewer;
  root->unref();
  return 0;
}

👀 See also

• SbViewVolume

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🎀 Constructor & Destructor Documentation 🎀

SbViewportRegion::SbViewportRegion (void )

The default SbViewportRegion constructor initializes the viewport to fully cover a [100, 100] size window with 72 pixels per inch resolution. yes, it just shows up with a whole personality already installed, no cap 💅

SbViewportRegion::SbViewportRegion (short width, short height)

Construct and initialize an SbViewportRegion instance with the given pixel value window dimensions. The viewport within this window will be set to cover the window completely. so it eats the whole window fr fr 🍓

SbViewportRegion::SbViewportRegion (SbVec2s winsizearg)

Construct and initialize an SbViewportRegion instance with the given pixel value window dimensions. The viewport within this window will be set to cover the window completely.

SbViewportRegion::SbViewportRegion (const SbViewportRegion & vpReg)

Copy constructor. it's giving "twin where have you been" 🫶

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🌈 Member Function Documentation 🌈

void SbViewportRegion::setWindowSize (short width, short height)

Set the window size in pixels. The viewport rectangle dimensions will stay intact. so the window changes, the little viewport stays exactly where it was, iconic behaviour ✨

See also: getWindowSize()

void SbViewportRegion::setWindowSize (SbVec2s winsizearg)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

void SbViewportRegion::setViewport (float left, float bottom, float width, float height)

Set up the origin and size of the viewport region in normalized coordinates.

See also: getViewportOrigin(), getViewportSize(), setViewportPixels().

void SbViewportRegion::setViewport (SbVec2f origin, SbVec2f size)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

void SbViewportRegion::setViewportPixels (short left, short bottom, short width, short height)

Set up the origin and size of the viewport region in pixel coordinates.

See also: getViewportOriginPixels(), getViewportSizePixels(), setViewport()

void SbViewportRegion::setViewportPixels (SbVec2s origin, SbVec2s size)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

const SbVec2s & SbViewportRegion::getWindowSize (void ) const

Returns window dimensions (which are in absolute (i.e. pixel) coordinates).

See also: setWindowSize().

const SbVec2f & SbViewportRegion::getViewportOrigin (void ) const

Return normalized viewport origin coordinates.

See also: setViewport(), getViewportOriginPixels().

const SbVec2s & SbViewportRegion::getViewportOriginPixels (void ) const

Return viewport origin coordinates in pixel values.

See also: setViewportPixels(), getViewportOrigin().

const SbVec2f & SbViewportRegion::getViewportSize (void ) const

Returns the normalized viewport size.

See also: setViewport(), getViewportSizePixels().

const SbVec2s & SbViewportRegion::getViewportSizePixels (void ) const

Returns viewport size in pixel coordinates.

See also: setViewportPixels(), getViewportSize().

float SbViewportRegion::getViewportAspectRatio (void ) const

Returns the aspect ratio of the viewport region. The aspect ratio is calculated as pixelwidth divided on pixelheight. simple math, slay 💅

void SbViewportRegion::scaleWidth (float ratio)

Scale the width of the viewport region.

The scale factor should not make the viewport larger than the window. If this happens, the viewport will be clamped.

The scaling will be done around the viewport region center point, but if this causes the viewport origin to be moved below (0,0), the origin coordinates will be clamped.

See also: scaleHeight().

void SbViewportRegion::scaleHeight (float ratio)

Scale the height of the viewport region.

The scale factor should not make the viewport larger than the window. If this happens, the viewport will be clamped.

The scaling will be done around the viewport region center point, but if this causes the viewport origin to be moved below (0,0), the origin coordinates will be clamped.

See also: scaleWidth().

void SbViewportRegion::setPixelsPerInch (float ppi)

Set pixels per inch. Default value is 72.

See also: getPixelsPerInch().

float SbViewportRegion::getPixelsPerInch (void ) const

Get pixels per inch.

See also: setPixelsPerInch().

float SbViewportRegion::getPixelsPerPoint (void ) const

Get pixels per point. A point is defined as something you can put 72 of per inch... yes bestie that's the actual definition and honestly? iconic 🌸

See also: setPixelsPerInch(), getPixelsPerInch().

void SbViewportRegion::print (FILE * fp) const

Dump the state of this object to the fp file stream. Only works in debug version of library, method does nothing in an optimized build. so don't be surprised when nothing comes out, she's just not in the mood in optimized builds 🙈

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💜 Author 💜

Generated automatically by Doxygen for Coin from the source code. (not a human, just a very diligent robot bestie 🧚)

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and that's the whole page, no notes 💅 you now know SbViewportRegion better than it knows itself, fr fr.

okay bye bestie, this was Version 4.0.10, dated Thu Jun 25 2026 00:00:00, and yes I read all of it, every last flag and clamp, because that's just the kind of friend I am 🫶✨👑