2D camera that defines what region is shown on framebuffer More...

#include <gf/View.h>

Inheritance diagram for gf::View:

[legend]

Public Member Functions
	View ()
	Default constructor. More...

	View (const RectF &rect)
	Construct the view from a rectangle. More...

	View (Vector2f center, Vector2f size)
	Construct the view from its center and size. More...

virtual	~View ()
	Destructor. More...

RectF	getBounds () const
	Get the non-rotated bounds. More...

void	setCenter (Vector2f center)
	Set the center of the view. More...

Vector2f	getCenter () const
	Get the center of the view. More...

void	setSize (Vector2f size)
	Set the size of the view. More...

Vector2f	getSize () const
	Get the size of the view. More...

void	setRotation (float angle)
	Set the orientation of the view. More...

float	getRotation () const
	Get the current orientation of the view. More...

void	setViewport (const RectF &viewport)
	Set the target viewport. More...

const RectF &	getViewport () const
	Get the target viewport rectangle of the view. More...

void	reset (const RectF &rect)
	Reset the view to the given rectangle. More...

void	move (Vector2f offset)
	Move the view relatively to its current position. More...

void	rotate (float angle)
	Rotate the view relatively to its current orientation. More...

void	zoom (float factor)
	Resize the view rectangle relatively to its current size. More...

void	zoom (float factor, Vector2f fixed)
	Resize the view rectangle relatively to its current size and a fixed point. More...

Matrix3f	getTransform () const
	Get the projection transform of the view. More...

Matrix3f	getInverseTransform () const
	Get the inverse projection transform of the view. More...

Protected Member Functions
void	setSizeNoCallback (Vector2f size)
	Set the world size, without calling onSizeChange() More...

virtual void	onSizeChange (Vector2f size)
	Callback when the world has just been resized. More...

void	setViewportNoCallback (const RectF &viewport)
	Set the viewport, without calling onViewportChange() More...

virtual void	onViewportChange (const RectF &viewport)
	Callback when the viewport has just been changed. More...

Detailed Description

2D camera that defines what region is shown on framebuffer

gf::View defines a camera in the 2D scene. This is a very powerful concept: you can scroll, rotate or zoom the entire scene without altering the way that your drawable objects are drawn.

A view is composed of a source rectangle, which defines what part of the 2D scene is shown, and a target viewport, which defines where the contents of the source rectangle will be displayed on the render target (window or texture).

The viewport allows to map the scene to a custom part of the render target, and can be used for split-framebuffer or for displaying a minimap, for example. If the source rectangle has not the same size as the viewport, its contents will be stretched to fit in.

To apply a view, you have to assign it to the render target. Then, every objects drawn in this render target will be affected by the view until you use another view.

Usage example:

gf::RenderWindow renderer;
gf::View view;
 
// Initialize the view to a rectangle located at (100, 100) and
// with a size of 400x200
view.reset({ 100.0f, 100.0f, 400.0f, 200.0f });
 
// Rotate it by 45 degrees
view.rotate(gf::Pi / 4);
 
// Set its target viewport to be half of the window
view.setViewport({ 0.f, 0.f, 0.5f, 1.f });
 
// Apply it
renderer.setView(view);
 
// Render stuff
renderer.draw(someSprite);
 
// Set the default view back
renderer.setView(renderer.getDefaultView());
 
// Render stuff not affected by the view
renderer.draw(someOtherSprite);

See also: gf::RenderTarget, gf::AdaptativeView

Constructor & Destructor Documentation

◆ View() [1/3]

gf::View::View ( )

Default constructor.

This constructor creates a default view of \((0, 0, 1000, 1000)\).

◆ View() [2/3]

gf::View::View ( const RectF & rect )

explicit

Construct the view from a rectangle.

Parameters

rect	Rectangle defining the zone to display

◆ View() [3/3]

gf::View::View	(	Vector2f	center,
		Vector2f	size
	)

Construct the view from its center and size.

Parameters

center	Center of the zone to display
size	Size of the zone to display

◆ ~View()

virtual gf::View::~View ( )

virtual

Destructor.

Member Function Documentation

◆ getBounds()

RectF gf::View::getBounds ( ) const

Get the non-rotated bounds.

Returns: A rectangle representing the non-rotated bounds of the view

◆ getCenter()

Vector2f gf::View::getCenter ( ) const

inline

Get the center of the view.

Returns: Center of the view

See also: setCenter()

◆ getInverseTransform()

Matrix3f gf::View::getInverseTransform ( ) const

Get the inverse projection transform of the view.

This function is meant for internal use only.

Returns: Inverse of the projection transform defining the view

See also: getTransform

◆ getRotation()

float gf::View::getRotation ( ) const

inline

Get the current orientation of the view.

Returns: Rotation angle of the view, in radians

See also: setRotation()

◆ getSize()

Vector2f gf::View::getSize ( ) const

inline

Get the size of the view.

Returns: Size of the view

See also: setSize()

◆ getTransform()

Matrix3f gf::View::getTransform ( ) const

Get the projection transform of the view.

This function is meant for internal use only.

Returns: Projection transform defining the view

See also: getInverseTransform()

◆ getViewport()

const RectF & gf::View::getViewport ( ) const

inline

Get the target viewport rectangle of the view.

Returns: Viewport rectangle, expressed as a factor of the target size

See also: setViewport()

◆ move()

void gf::View::move ( Vector2f offset )

Move the view relatively to its current position.

Parameters

offset Move offset

See also: setCenter(), rotate(), zoom()

◆ onSizeChange()

virtual void gf::View::onSizeChange ( Vector2f size )

protectedvirtual

Callback when the world has just been resized.

This callback is called when setSize() is called.

Parameters

size	The new size of the visible world

Reimplemented in gf::FitView, gf::FillView, gf::ExtendView, and gf::LockedView.

◆ onViewportChange()

virtual void gf::View::onViewportChange ( const RectF & viewport )

protectedvirtual

Callback when the viewport has just been changed.

Parameters

viewport The new viewport

Reimplemented in gf::FitView, gf::FillView, gf::ExtendView, gf::LockedView, and gf::ScreenView.

◆ reset()

void gf::View::reset ( const RectF & rect )

Reset the view to the given rectangle.

Note that this function resets the rotation angle to 0.

Parameters

rect	Rectangle defining the zone to display

See also: setCenter(), setSize(), setRotation()

◆ rotate()

void gf::View::rotate ( float angle )

Rotate the view relatively to its current orientation.

Parameters

angle Angle to rotate, in radians

See also: setRotation(), move(), zoom()

◆ setCenter()

void gf::View::setCenter ( Vector2f center )

inline

Set the center of the view.

Parameters

center New center

See also: getCenter()

◆ setRotation()

void gf::View::setRotation ( float angle )

inline

Set the orientation of the view.

The default rotation of a view is 0 radians.

Parameters

angle New angle, in radians

See also: getRotation()

◆ setSize()

void gf::View::setSize ( Vector2f size )

inline

Set the size of the view.

Parameters

size New size

See also: getSize()

◆ setSizeNoCallback()

void gf::View::setSizeNoCallback ( Vector2f size )

inlineprotected

Set the world size, without calling onSizeChange()

This function is meant for adaptative views so that they can adapt the world size without having a callback infinite loop.

Parameters

size	The new world size

◆ setViewport()

void gf::View::setViewport ( const RectF & viewport )

Set the target viewport.

The viewport is the rectangle into which the contents of the view are displayed, expressed as a factor (between 0 and 1) of the size of the RenderTarget to which the view is applied.

For example, a view which takes the left side of the target would be defined with:

view.setViewport({0.0f, 0.0f, 0.5f, 1.0f}).

By default, a view has a viewport which covers the entire target.

Parameters

viewport New viewport rectangle

See also: getViewport()

◆ setViewportNoCallback()

void gf::View::setViewportNoCallback ( const RectF & viewport )

protected

Set the viewport, without calling onViewportChange()

This function is meant for adaptative views so that they can adapt the viewport without having a callback infinite loop.

Parameters

viewport The new viewport

◆ zoom() [1/2]

void gf::View::zoom ( float factor )

Resize the view rectangle relatively to its current size.

Resizing the view simulates a zoom, as the zone displayed on framebuffer grows or shrinks. factor is a multiplier:

\( = 1 \) keeps the size unchanged
\( > 1 \) makes the view bigger (objects appear smaller)
\( < 1 \) makes the view smaller (objects appear bigger)

Parameters

factor Zoom factor to apply

See also: setSize(), move(), rotate()

◆ zoom() [2/2]

void gf::View::zoom	(	float	factor,
		Vector2f	fixed
	)

Resize the view rectangle relatively to its current size and a fixed point.

Resizing the view simulates a zoom, as the zone displayed on framebuffer grows or shrinks. factor is a multiplier:

\( = 1 \) keeps the size unchanged
\( > 1 \) makes the view bigger (objects appear smaller)
\( < 1 \) makes the view smaller (objects appear bigger)

Additionally, a fixed point is used as the center of the zoom. It is the only point that stays at the same place in the view.

Parameters

factor	Zoom factor to apply
fixed	The center of the zoom

See also: setSize(), move(), rotate()

Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ View() [1/3]

◆ View() [2/3]

◆ View() [3/3]

◆ ~View()

Member Function Documentation

◆ getBounds()

◆ getCenter()

◆ getInverseTransform()

◆ getRotation()

◆ getSize()

◆ getTransform()

◆ getViewport()

◆ move()

◆ onSizeChange()

◆ onViewportChange()

◆ reset()

◆ rotate()

◆ setCenter()

◆ setRotation()

◆ setSize()

◆ setSizeNoCallback()

◆ setViewport()

◆ setViewportNoCallback()

◆ zoom() [1/2]

◆ zoom() [2/2]