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Public Member Functions
StelProjectorPerspective Class Reference

Public Member Functions

 StelProjectorPerspective (ModelViewTranformP func)
 
QString getNameI18 () const override
 Get a human-readable name for this projection type.
 
QString getDescriptionI18 () const override
 Get a human-readable short description for this projection type.
 
float getMaxFov () const override
 Get the maximum FOV aperture in degree.
 
bool forward (Vec3f &v) const override
 Apply the transformation in the forward direction in place. More...
 
bool backward (Vec3d &v) const override
 Apply the transformation in the backward projection in place.
 
float fovToViewScalingFactor (float fov) const override
 Convert a Field Of View radius value in radians in ViewScalingFactor (used internally)
 
float viewScalingFactorToFov (float vsf) const override
 Convert a ViewScalingFactor value (used internally) in Field Of View radius in radians.
 
float deltaZoom (float fov) const override
 Return the small zoom increment to use at the given FOV for nice movements.
 
QByteArray getForwardTransformShader () const override
 Returns GLSL code that can be used in a shader to implement forward transformation.
 
QByteArray getBackwardTransformShader () const override
 Returns GLSL code that can be used in a shader to implement backward transformation.
 
- Public Member Functions inherited from StelProjector
virtual ~StelProjector ()
 Destructor.
 
QString getHtmlSummary () const
 Get a HTML version of the short description for this projection type.
 
virtual void setForwardTransformUniforms (QOpenGLShaderProgram &program) const
 Sets the necessary uniforms so that the shader returned by getForwardTransformShader can work.
 
virtual void setBackwardTransformUniforms (QOpenGLShaderProgram &program) const
 Sets the necessary uniforms so that the shader returned by getBackwardTransformShader can work.
 
bool intersectViewportDiscontinuity (const Vec3d &p1, const Vec3d &p2) const
 Determine whether a great circle connection p1 and p2 intersects with a projection discontinuity. More...
 
bool intersectViewportDiscontinuity (const SphericalCap &cap) const
 
bool getFlagGravityLabels () const
 Get the current state of the flag which decides whether to arrange labels so that they are aligned with the bottom of a 2d screen, or a 3d dome.
 
const Vec4igetViewport () const
 Get the lower left corner of the viewport and the width, height.
 
Vector2< qreal > getViewportCenter () const
 Get the center of the viewport relative to the lower left corner of the screen.
 
Vector2< qreal > getViewportCenterOffset () const
 
int getViewportPosX () const
 Get the horizontal viewport offset in pixels.
 
int getViewportPosY () const
 Get the vertical viewport offset in pixels.
 
int getViewportWidth () const
 Get the viewport width in pixels.
 
int getViewportHeight () const
 Get the viewport height in pixels.
 
qreal getDevicePixelsPerPixel () const
 Get the number of device pixels per "Device Independent Pixels" (value is usually 1, but 2 for mac retina screens).
 
SphericalRegionP getViewportConvexPolygon (float marginX=0., float marginY=0.) const
 Return a convex polygon on the sphere which includes the viewport in the current frame. More...
 
const SphericalCapgetBoundingCap () const
 Return a SphericalCap containing the whole viewport.
 
float getPixelPerRadAtCenter () const
 Get size of a radian in pixels at the center of the viewport disk.
 
float getFov () const
 Get the current FOV diameter in degrees.
 
bool needGlFrontFaceCW () const
 Get whether front faces need to be oriented in the clockwise direction.
 
bool checkInViewport (const Vec3d &pos) const
 Check to see if a 2d position is inside the viewport. More...
 
bool checkInViewport (const Vec3f &pos) const
 Check to see if a 2d position is inside the viewport. More...
 
Vec3d viewPortIntersect (const Vec3d &p1, const Vec3d &p2) const
 Return the position where the 2 2D point p1 and p2 cross the viewport edge P1 must be inside the viewport and P2 outside (check with checkInViewport() before calling this method)
 
bool project (const Vec3d &v, Vec3d &win) const
 Project the vector v from the current frame into the viewport. More...
 
bool project (const Vec3f &v, Vec3f &win) const
 Project the vector v from the current frame into the viewport. More...
 
bool project (const Vec3d &v, Vec3f &win) const
 Project the vector v from the current frame into the viewport. More...
 
virtual void project (int n, const Vec3d *in, Vec3f *out)
 
virtual void project (int n, const Vec3f *in, Vec3f *out)
 
bool projectInPlace (Vec3d &vd) const
 Project the vector v from the current frame into the viewport. More...
 
bool projectInPlace (Vec3f &v) const
 Project the vector v from the current frame into the viewport. More...
 
bool projectCheck (const Vec3d &v, Vec3d &win) const
 Project the vector v from the current frame into the viewport. More...
 
bool projectCheck (const Vec3f &v, Vec3f &win) const
 Project the vector v from the current frame into the viewport. More...
 
bool unProject (const Vec3d &win, Vec3d &v) const
 Project the vector v from the viewport frame into the current frame. More...
 
bool unProject (double x, double y, Vec3d &v) const
 
bool projectLineCheck (const Vec3d &v1, Vec3d &win1, const Vec3d &v2, Vec3d &win2) const
 Project the vectors v1 and v2 from the current frame into the viewport. More...
 
QByteArray getProjectShader () const
 
void setProjectUniforms (QOpenGLShaderProgram &program) const
 
QByteArray getUnProjectShader () const
 
void setUnProjectUniforms (QOpenGLShaderProgram &program) const
 
ModelViewTranformP getModelViewTransform () const
 Get the current model view matrix.
 
Mat4f getProjectionMatrix () const
 Get the current projection matrix.
 
StelProjectorMaskType getMaskType (void) const
 Get the current type of the mask if any.
 
bool isSameProjection (const StelProjector &other) const
 Check whether the projection represented by other is the same as this. More...
 

Additional Inherited Members

- Public Types inherited from StelProjector
enum  StelProjectorMaskType { MaskNone , MaskDisk }
 Define viewport mask types. More...
 
typedef QSharedPointer< ModelViewTranformModelViewTranformP
 Shared pointer on a ModelViewTranform instance (implement reference counting)
 
- Static Public Member Functions inherited from StelProjector
static const QString maskTypeToString (StelProjectorMaskType type)
 Get a string description of a StelProjectorMaskType.
 
static StelProjectorMaskType stringToMaskType (const QString &s)
 Get a StelProjectorMaskType from a string description.
 
- Protected Member Functions inherited from StelProjector
 StelProjector (ModelViewTranformP amodelViewTransform)
 Private constructor. Only StelCore can create instances of StelProjector.
 
virtual bool hasDiscontinuity () const
 Return whether the projection presents discontinuities. Used for optimization.
 
virtual bool intersectViewportDiscontinuityInternal (const Vec3d &p1, const Vec3d &p2) const
 Determine whether a great circle connection p1 and p2 intersects with a projection discontinuity. More...
 
virtual bool intersectViewportDiscontinuityInternal (const Vec3d &capN, double capD) const
 Determine whether a cap intersects with a projection discontinuity.
 
virtual void computeBoundingCap ()
 Initialize the bounding cap.
 
- Protected Attributes inherited from StelProjector
ModelViewTranformP modelViewTransform
 
float flipHorz
 
float flipVert
 
float pixelPerRad
 
StelProjectorMaskType maskType
 
double zNear
 
double oneOverZNearMinusZFar
 
Vec4i viewportXywh
 
Vector2< qreal > viewportCenter
 
Vector2< qreal > viewportCenterOffset
 
qreal viewportFovDiameter
 
bool gravityLabels
 
float defaultAngleForGravityText
 
SphericalCap boundingCap
 
qreal devicePixelsPerPixel
 
qreal widthStretch
 

Member Function Documentation

◆ forward()

bool StelProjectorPerspective::forward ( Vec3f v) const
overridevirtual

Apply the transformation in the forward direction in place.

After transformation v[2] will always contain the length of the original v: sqrt(v[0]*v[0]+v[1]*v[1]+v[2]*v[2]) regardless of the projection type. This makes it possible to implement depth buffer testing in a way independent of the projection type. I would like to return the squared length instead of the length because of performance reasons. But then far away objects are not textured any more, perhaps because of a depth buffer overflow although the depth test is disabled?

Implements StelProjector.