View – vkframes

type, public :: View

A view (see the module documentation).

Inherits

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Inherited by

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Components

Type	Visibility	Attributes		Name		Initial
logical,	private		::	camera_pending	=	.false.	true if `pending` is to be applied when shown
real(kind=wp),	private		::	center(3)	=	0.0_wp	kept center
real(kind=wp),	private		::	default_center(3)	=	0.0_wp	camera center after a reset (view-frame coordinates)
real(kind=wp),	private		::	default_distance	=	0.0_wp	radius framed on reset (<= 0: the frame's bound)
real(kind=wp),	private		::	default_eye(3)	=	0.0_wp	camera eye after a reset (view-frame coordinates)
real(kind=wp),	private		::	default_up(3)	=	0.0_wp	camera up after a reset (zero: no default camera)
real(kind=wp),	private		::	eye(3)	=	0.0_wp	kept eye
real(kind=wp),	private		::	fovy	=	45.0_wp	vertical field of view (degrees)
class(ReferenceFrame),	private,	pointer	::	frame	=>	null()	the viewed frame (not owned)
integer,	private		::	frame_type	=	RELATIVE_FRAME	ABSOLUTE_FRAME or RELATIVE_FRAME
logical,	private		::	has_state	=	.false.	true if eye, center, up are kept
class(ReferenceFrame),	private,	pointer	::	lookat	=>	null()	the frame looked at (view between frames; not owned)
real(kind=wp),	private		::	ortho(4)	=	[-1.0_wp, 1.0_wp, -1.0_wp, 1.0_wp]	left, right, bottom, top
real(kind=wp),	private		::	pending(3,3)	=	0.0_wp	a camera set (eye, center, up), for when it is shown
integer,	private		::	projection	=	PERSPECTIVE	ORTHOGRAPHIC or PERSPECTIVE
logical,	private		::	reset_pending	=	.true.	true if the camera is to be reset when shown
class(ReferenceFrame),	private,	pointer	::	root	=>	null()	the root of the frames' tree (not owned)
integer,	private		::	rotation_type	=	VIEW_AZEL	VIEW_DIRECT or VIEW_AZEL
real(kind=wp),	private		::	up(3)	=	0.0_wp	kept up direction

Constructor

public interface View

The View constructor: View(...) makes one (see new_view for its arguments).

private function new_view(root, frame, lookat, frame_type, rotation_type) result(v)

A view of frame (in the tree of root), with base frame_type (default RELATIVE_FRAME); with lookat, a view from frame at lookat, turned by rotation_type (default VIEW_AZEL). Without frames, the view looks at the root frame's origin. The frames must stay alive while the view is used.

Arguments

Type	Intent	Optional	Attributes		Name
class(ReferenceFrame),	intent(in),	optional,	target	::	root	the tree's root, viewed and looked-at frames
class(ReferenceFrame),	intent(in),	optional,	target	::	frame	the tree's root, viewed and looked-at frames
class(ReferenceFrame),	intent(in),	optional,	target	::	lookat	the tree's root, viewed and looked-at frames
integer,	intent(in),	optional		::	frame_type	ABSOLUTE_FRAME or RELATIVE_FRAME
integer,	intent(in),	optional		::	rotation_type	VIEW_DIRECT or VIEW_AZEL

Return Value type(View)

Type-Bound Procedures

procedure, public :: clear_default_view_parameters

private subroutine clear_default_view_parameters(self)

Forget the camera set by set_default_view_parameters (back to the default view distance).

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(inout)			::	self

procedure, public :: default_view_distance

private pure function default_view_distance(self)

The radius framed when the view is reset (<= 0: the viewed frame's bound).

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(in)			::	self

Return Value real(kind=wp)

procedure, public :: default_view_parameters

private pure subroutine default_view_parameters(self, eye, center, up)

The camera after a reset (view-frame coordinates; all zero if none is set).

Arguments

Type	Intent		Name
class(View),	intent(in)	::	self
real(kind=wp),	intent(out)	::	eye(3)	the camera (view-frame coordinates; zero if not set)
real(kind=wp),	intent(out)	::	center(3)	the camera (view-frame coordinates; zero if not set)
real(kind=wp),	intent(out)	::	up(3)	the camera (view-frame coordinates; zero if not set)

procedure, public :: field_of_view

private pure function field_of_view(self) result(fovy)

The vertical field of view (degrees) of the perspective projection.

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(in)			::	self

Return Value real(kind=wp)

procedure, public :: home

private subroutine home(self, aspect, eye, center, up)

The default camera (eye, center, up in view-frame coordinates) for a viewport of aspect ratio aspect (width / height): OpenFrames' resetView.

Arguments

Type	Intent		Name
class(View),	intent(in)	::	self
real(kind=wp),	intent(in)	::	aspect	viewport width / height
real(kind=wp),	intent(out)	::	eye(3)	the default camera (view-frame coordinates)
real(kind=wp),	intent(out)	::	center(3)	the default camera (view-frame coordinates)
real(kind=wp),	intent(out)	::	up(3)	the default camera (view-frame coordinates)

procedure, public :: is_valid

private function is_valid(self)

True if the view has a frame to view.

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(in)			::	self

Return Value logical

procedure, public :: lookat_frame

private function lookat_frame(self) result(f)

The frame looked at, for a view between frames (null if none).

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(in)			::	self

Return Value class(ReferenceFrame), pointer

procedure, public :: orthographic_bounds

private pure function orthographic_bounds(self) result(bounds)

The bounds [left, right, bottom, top] of the orthographic projection.

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(in)			::	self

Return Value real(kind=wp), (4)

procedure, public :: projection_type

private pure function projection_type(self)

The projection: ORTHOGRAPHIC or PERSPECTIVE.

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(in)			::	self

Return Value integer

procedure, public :: reset_view

private subroutine reset_view(self)

Put the camera back at the default position (applied at the next frame in which the view is shown).

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(inout)			::	self

procedure, public :: save_state

private subroutine save_state(self, eye, center, up)

Keep the trackball state while another view is shown.

Arguments

Type	Intent		Name
class(View),	intent(inout)	::	self
real(kind=wp),	intent(in)	::	eye(3)	the trackball state (view-frame coordinates)
real(kind=wp),	intent(in)	::	center(3)	the trackball state (view-frame coordinates)
real(kind=wp),	intent(in)	::	up(3)	the trackball state (view-frame coordinates)

procedure, public :: saved_state

private function saved_state(self, eye, center, up)

The kept trackball state; false if there is none.

Arguments

Type	Intent		Name
class(View),	intent(in)	::	self
real(kind=wp),	intent(out)	::	eye(3)	the kept trackball state (view-frame coordinates)
real(kind=wp),	intent(out)	::	center(3)	the kept trackball state (view-frame coordinates)
real(kind=wp),	intent(out)	::	up(3)	the kept trackball state (view-frame coordinates)

Return Value logical

procedure, public :: set_camera => view_set_camera

private subroutine view_set_camera(self, eye, center, up)

The camera (view-frame coordinates) to show the next time the view is drawn (at once if it is shown: the window's set_camera can also fly there). It replaces a pending reset.

Arguments

Type	Intent		Name
class(View),	intent(inout)	::	self
real(kind=wp),	intent(in)	::	eye(3)	the camera (view-frame coordinates)
real(kind=wp),	intent(in)	::	center(3)	the camera (view-frame coordinates)
real(kind=wp),	intent(in)	::	up(3)	the camera (view-frame coordinates)

procedure, public :: set_default_view_distance

private subroutine set_default_view_distance(self, distance)

The radius to frame when the view is reset (<= 0: the viewed frame's bound, the default), as OpenFrames' default view distance.

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(inout)			::	self
real(kind=wp),	intent(in)			::	distance	radius (<= 0: the frame's bound)

procedure, public :: set_default_view_parameters

private subroutine set_default_view_parameters(self, eye, center, up)

The camera after a reset, in view-frame coordinates (overrides the default view distance).

Arguments

Type	Intent		Name
class(View),	intent(inout)	::	self
real(kind=wp),	intent(in)	::	eye(3)	the camera (view-frame coordinates)
real(kind=wp),	intent(in)	::	center(3)	the camera (view-frame coordinates)
real(kind=wp),	intent(in)	::	up(3)	the camera (view-frame coordinates)

procedure, public :: set_orthographic

private subroutine set_orthographic(self, left, right, bottom, top)

An orthographic projection with the given bounds (in view units).

Arguments

Type	Intent		Name
class(View),	intent(inout)	::	self
real(kind=wp),	intent(in)	::	left	bounds (view units)
real(kind=wp),	intent(in)	::	right	bounds (view units)
real(kind=wp),	intent(in)	::	bottom	bounds (view units)
real(kind=wp),	intent(in)	::	top	bounds (view units)

procedure, public :: set_perspective

private subroutine set_perspective(self, fovy)

A perspective projection with vertical field of view fovy (degrees; default 45).

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(inout)			::	self
real(kind=wp),	intent(in)			::	fovy	vertical field of view (degrees)

procedure, public :: set_view_between_frames

private subroutine set_view_between_frames(self, root, frame, lookat, frame_type, rotation_type)

Look from frame at lookat (both in the tree of root).

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(inout)			::	self
class(ReferenceFrame),	intent(in),		target	::	root	the tree's root, viewed and looked-at frames
class(ReferenceFrame),	intent(in),		target	::	frame	the tree's root, viewed and looked-at frames
class(ReferenceFrame),	intent(in),		target	::	lookat	the tree's root, viewed and looked-at frames
integer,	intent(in),	optional		::	frame_type	ABSOLUTE_FRAME or RELATIVE_FRAME (default)
integer,	intent(in),	optional		::	rotation_type	VIEW_DIRECT or VIEW_AZEL (default)

procedure, public :: set_view_frame

private subroutine set_view_frame(self, root, frame, frame_type)

View frame (in the tree of root) with base frame_type (default RELATIVE_FRAME).

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(inout)			::	self
class(ReferenceFrame),	intent(in),		target	::	root	the tree's root; the viewed frame (not owned)
class(ReferenceFrame),	intent(in),		target	::	frame	the tree's root; the viewed frame (not owned)
integer,	intent(in),	optional		::	frame_type	ABSOLUTE_FRAME or RELATIVE_FRAME

procedure, public :: take_camera

private function take_camera(self, cam)

True (once) if a camera was set (set_camera), and that camera.

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(inout)			::	self
real(kind=wp),	intent(out)			::	cam(3,3)	(columns: eye, center, up (view-frame coordinates))

Return Value logical

procedure, public :: take_reset

private function take_reset(self)

True (once) if a reset is pending.

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(inout)			::	self

Return Value logical

procedure, public :: view_frame

private function view_frame(self) result(f)

The viewed frame (null if none).

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(in)			::	self

Return Value class(ReferenceFrame), pointer

procedure, public :: view_frame_type

private pure function view_frame_type(self)

The base of the trackball: ABSOLUTE_FRAME or RELATIVE_FRAME.

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(in)			::	self

Return Value integer

procedure, public :: view_root

private function view_root(self) result(f)

The root of the viewed frames' tree (null if none).

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(in)			::	self

Return Value class(ReferenceFrame), pointer

procedure, public :: view_rotation_type

private pure function view_rotation_type(self)

How a view between frames turns: VIEW_DIRECT or VIEW_AZEL.

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(in)			::	self

Return Value integer

procedure, public :: world_to_view

private function world_to_view(self) result(m)

The transform from the root frame to the view frame (4x4), from the frames' current positions and attitudes.

Arguments

Type	Intent	Optional	Attributes		Name
class(View),	intent(in)			::	self

Return Value real(kind=wp), (4,4)

Source Code

    type, public :: View
        private
        class(ReferenceFrame), pointer :: root => null()    !! the root of the frames' tree (not owned)
        class(ReferenceFrame), pointer :: frame => null()   !! the viewed frame (not owned)
        class(ReferenceFrame), pointer :: lookat => null()  !! the frame looked at (view between frames; not owned)
        integer :: frame_type = RELATIVE_FRAME              !! ABSOLUTE_FRAME or RELATIVE_FRAME
        integer :: rotation_type = VIEW_AZEL                !! VIEW_DIRECT or VIEW_AZEL
        integer :: projection = PERSPECTIVE                 !! ORTHOGRAPHIC or PERSPECTIVE
        real(wp) :: fovy = 45.0_wp                          !! vertical field of view (degrees)
        real(wp) :: ortho(4) = [-1.0_wp, 1.0_wp, -1.0_wp, 1.0_wp]   !! left, right, bottom, top
        real(wp) :: default_distance = 0.0_wp               !! radius framed on reset (<= 0: the frame's bound)
        real(wp) :: default_eye(3) = 0.0_wp                 !! camera eye after a reset (view-frame coordinates)
        real(wp) :: default_center(3) = 0.0_wp              !! camera center after a reset (view-frame coordinates)
        real(wp) :: default_up(3) = 0.0_wp                  !! camera up after a reset (zero: no default camera)
        ! the trackball state of this view (view-frame coordinates), kept while another view is shown
        real(wp) :: eye(3) = 0.0_wp                         !! kept eye
        real(wp) :: center(3) = 0.0_wp                      !! kept center
        real(wp) :: up(3) = 0.0_wp                          !! kept up direction
        logical :: has_state = .false.                      !! true if eye, center, up are kept
        logical :: reset_pending = .true.                   !! true if the camera is to be reset when shown
        real(wp) :: pending(3,3) = 0.0_wp                  !! a camera set (eye, center, up), for when it is shown
        logical :: camera_pending = .false.                 !! true if `pending` is to be applied when shown
    contains
        procedure :: set_view_frame, set_view_between_frames
        procedure :: view_root, view_frame, lookat_frame, view_frame_type, view_rotation_type, is_valid
        procedure :: set_perspective, field_of_view, set_orthographic, orthographic_bounds, projection_type
        procedure :: set_default_view_distance, default_view_distance
        procedure :: set_default_view_parameters, default_view_parameters, clear_default_view_parameters
        procedure :: reset_view
        procedure :: world_to_view, home
        procedure :: save_state, saved_state, take_reset
        procedure :: set_camera => view_set_camera, take_camera
    end type View

View Derived Type

Contents

Variables

Constructor

Type-Bound Procedures

Source Code

type, public :: View

Inherits

Inherited by

Components

Constructor

public interface View

private function new_view(root, frame, lookat, frame_type, rotation_type) result(v)

Arguments

Return Value type(View)

Type-Bound Procedures

procedure, public :: clear_default_view_parameters

private subroutine clear_default_view_parameters(self)

Arguments

procedure, public :: default_view_distance

private pure function default_view_distance(self)

Arguments

Return Value real(kind=wp)

procedure, public :: default_view_parameters

private pure subroutine default_view_parameters(self, eye, center, up)

Arguments

procedure, public :: field_of_view

private pure function field_of_view(self) result(fovy)

Arguments

Return Value real(kind=wp)

procedure, public :: home

private subroutine home(self, aspect, eye, center, up)

Arguments

procedure, public :: is_valid

private function is_valid(self)

Arguments

Return Value logical

procedure, public :: lookat_frame

private function lookat_frame(self) result(f)

Arguments

Return Value class(ReferenceFrame), pointer

procedure, public :: orthographic_bounds

private pure function orthographic_bounds(self) result(bounds)

Arguments

Return Value real(kind=wp), (4)

procedure, public :: projection_type

private pure function projection_type(self)

Arguments

Return Value integer

procedure, public :: reset_view

private subroutine reset_view(self)

Arguments

procedure, public :: save_state

private subroutine save_state(self, eye, center, up)

Arguments

procedure, public :: saved_state

private function saved_state(self, eye, center, up)

Arguments

Return Value logical

procedure, public :: set_camera => view_set_camera

private subroutine view_set_camera(self, eye, center, up)

Arguments

procedure, public :: set_default_view_distance

private subroutine set_default_view_distance(self, distance)

Arguments

procedure, public :: set_default_view_parameters

private subroutine set_default_view_parameters(self, eye, center, up)

Arguments

procedure, public :: set_orthographic

private subroutine set_orthographic(self, left, right, bottom, top)

Arguments

procedure, public :: set_perspective

private subroutine set_perspective(self, fovy)

Arguments

procedure, public :: set_view_between_frames

private subroutine set_view_between_frames(self, root, frame, lookat, frame_type, rotation_type)

Arguments

procedure, public :: set_view_frame

private subroutine set_view_frame(self, root, frame, frame_type)

Arguments