SbViewportRegion(3)

📦 version 3.1.3, in fedora 43, fedora 44

💖 SbViewportRegion(3) — Library Functions Manual 💖

okay bestie, welcome to the Coin docs, this one's from the Library Functions Manual and it's honestly kind of iconic ✨

🌸 NAME 🌸

SbViewportRegion — the SbViewportRegion class is a viewport within a full window. that's the whole vibe. a little rectangle inside a bigger rectangle. the rectangle-ception of it all 💅

🦋 SYNOPSIS 🦋

#include <Inventor/SbViewportRegion.h>

✨ Public Member Functions ✨

no cap, here's the full squad of methods, every single one:

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

🌈 Detailed Description 🌈

okay so, the SbViewportRegion class is a viewport within a full window. say it with me.

The SbViewportRegion class contains information to represent a subview within a window. It stores info about the origin and size of that subview, plus the size of the underlying "full" window. it's giving ✨nested rectangles✨ and we're obsessed 🫶

Available methods include inquiries and manipulation in both normalized coordinates and pixel coordinates. so you can speak either language, bilingual queen 👑

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'. literally so fun, go try it 😭

// Copyright (C) 2000-2010 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

🎀 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 bestie, it comes pre-loaded with defaults, main character energy from the jump 👑

`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. full coverage, no gaps, we love to see it 💖

`SbViewportRegion::SbViewportRegion (SbVec2s winsizearg)`

`SbViewportRegion::SbViewportRegion (const SbViewportRegion & vpReg)`

Copy constructor. it's a clone, it's a twin, it's a dupe that slays 🦋

💅 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 viewport itself doesn't move or resize, it's just the window around it changing. lowkey considerate ngl.

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. same girl, different outfit 💅

`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. math girlies rise 🧮✨

`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. so it self-corrects, it's got boundaries, we respect that 💜

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. same rules, different axis, twin behaviour fr fr.

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... yeah that's the definition, take it up with typography 😭

See also

setPixelsPerInch(), getPixelsPerInch().

`void SbViewportRegion::print (FILE * fp) const`

Dump the state of this object to the file stream.

Only works in debug version of library, method does nothing in an optimized compile. so if your print is printing nothing, bestie, that's not a bug, that's the build 💀

🌟 Author 🌟

Generated automatically by Doxygen for Coin from the source code. yeah the robot wrote it, and honestly? it ate.

and that's the whole page, bestie 🥰 this was Coin, Version 3.1.3, SbViewportRegion(3) — thanks for reading, mwah 💖🎀✨

📦 where this page comes from

fedora 43: Coin3-devel 3.1.3-40.fc43 · GPL-2.0-only
fedora 43: Coin3-devel 3.1.3-40.fc43 · GPL-2.0-only
fedora 44: Coin3-devel 3.1.3-42.fc44 · GPL-2.0-only
fedora 44: Coin3-devel 3.1.3-42.fc44 · GPL-2.0-only
💖 girlified by deepseek-ai/DeepSeek-V4.1-Flash on 2026-10-14: a language model's rewrite of the original, under its terms