Package com.massifmaps.graphics

Class ViewState

java.lang.Object
com.massifmaps.graphics.ViewState
public class ViewState extends Object
A class containing various view parameters for a view state.

  • Method Summary

    Modifier and Type
    Method
    Description
    double
    calculateCameraDistance()
    The distance from the camera to the focus point - tangram's m_pos.z, which is what their
    near and far planes are built on.
    SWIGTYPE_p_cglib__vec3T_double_t
    calculateViewDir()
    Returns the unit direction the camera looks along, including the look above the horizon
    that a negative tilt adds.
    double
    calculateViewDistance(Options options)
    How far from the camera the map is drawn, in internal units - tangram's rule, scaled by
    TerrainOptions::ViewDistanceFactor.
    void
    clearTerrainCameraReference()
    Turns the terrain zoom bound off (no terrain, or a non-planar projection).
    boolean
    equals(Object obj)
    Checks if this object is equal to the specified object.
    float
    getAspectRatio()
    Returns the aspect ratio of the map screen.
    float
    getCameraTilt()
    Returns the tilt the CAMERA POSITION is built at: the camera-to-focus vector is at this
    angle, never below the horizon, and the difference to the view tilt is a rotation of the
    view about the camera (see calculateLookatMat).
    float
    getDPI()
    Returns the dots per inch parameter of the screen.
    float
    getDPToPX()
    Returns a value that is used for converting display independent pixels (dp) to pixels (px).
    This values depends on the screen density.
    float
    getFar()
    Returns the far plane distance.
    int
    getFOVY()
    Returns the vertical field of view angle.
    int
    getHeight()
    Returns the height of the map screen.
    SWIGTYPE_p_cglib__frustum3T_double_t
    getLabelFrustum()
    Returns the view frustum grown by the label padding band, the one tiles must reach for
    their labels to be placed before they scroll in.
    float
    getNear()
    Returns the near plane distance.
    double
    getOrbitDistance(float zoom)
    Returns the camera-to-focus distance at the given zoom, what the zoom is calibrated on.
    float
    getRenderZoom()
    The zoom the RENDERER works in: the reported zoom plus Options::ZoomOffset.
    float
    getRotation()
    Returns the camera rotation angle.
    int
    getScreenHeight()
    Returns the screen height.
    int
    getScreenWidth()
    Returns the screen width.
    float
    getSkyHorizonNDC()
    Returns the normalized device y below which no ray from the screen reaches the sky -
    the horizon, in other words, in the space the sky quad is drawn in.
    float
    getTerrainMaxZoom()
    Returns the maximum zoom allowed by the terrain clearance, or infinity when
    no terrain bound is active.
    float
    getTilt()
    Returns the camera tilt angle.
    float
    getUnitToDPCoef()
    Returns the conversion ratio between internal map units and screen density independent pixels (DP or DIP).
    float
    getUnitToPXCoef()
    Returns the conversion ratio between internal map units and screen pixels.
    int
    getWidth()
    Returns the width of the map screen.
    float
    getZoom()
    Returns the camera zoom level.
    float
    getZoom0Distance()
    Returns the distance between the focus and the camera position, when the zoom level is set to 0.
    This parameter depends on the screen size, DPI, tile draw size and field of view settings.
    int
    hashCode()
    Returns the hash value of this object.
    boolean
    isCameraChanged()
    Returns the state of the camera changed flag.
    void
    liftFocus(double deltaZ)
    Moves the focus AND the camera by deltaZ, keeping zoom, tilt and rotation: the
    camera-to-focus vector is untouched.
    void
    setTerrainHeightRange(float minZ, float maxZ)
    Sets the terrain height range (in internal units).
    void
    setViewTilt(float tilt)
    Sets the tilt of the VIEW only, leaving the camera where it is.

    Methods inherited from class java.lang.Object

    clone, getClass, notify, notifyAll, toString, wait, wait, wait

  • Method Details

    • equals

      public boolean equals(Object obj)
      Checks if this object is equal to the specified object.
      Overrides:
      equals in class Object
      Parameters:
      obj - The reference object.
      Returns:
      True when objects are equal, false otherwise.

    • hashCode

      public int hashCode()
      Returns the hash value of this object.
      Overrides:
      hashCode in class Object
      Returns:
      The hash value of this object.

    • liftFocus

      public void liftFocus(double deltaZ)
      Moves the focus AND the camera by deltaZ, keeping zoom, tilt and rotation: the
      camera-to-focus vector is untouched. MapRenderer uses it to keep the focus ON the
      terrain under it, which is what makes the zoom the camera's distance to the ground at
      the focus, as in mapbox, rather than to sea level.

    • getTilt

      public float getTilt()
      Returns the camera tilt angle. A NEGATIVE tilt means the view looks above the horizon.
      Returns:
      The camera tilt angle in degrees.

    • setViewTilt

      public void setViewTilt(float tilt)
      Sets the tilt of the VIEW only, leaving the camera where it is. The difference between
      the camera tilt and this one is applied as a rotation of the view about the camera, so
      the camera does not move at all - which is what a first person look is.
      Parameters:
      tilt - The new view tilt angle in degrees.

    • getCameraTilt

      public float getCameraTilt()
      Returns the tilt the CAMERA POSITION is built at: the camera-to-focus vector is at this
      angle, never below the horizon, and the difference to the view tilt is a rotation of the
      view about the camera (see calculateLookatMat).
      Returns:
      The camera tilt angle in degrees, never negative.

    • calculateViewDir

      public SWIGTYPE_p_cglib__vec3T_double_t calculateViewDir()
      Returns the unit direction the camera looks along, including the look above the horizon
      that a negative tilt adds.
      Returns:
      The view direction, or a zero vector if the camera and the focus coincide.

    • getZoom

      public float getZoom()
      Returns the camera zoom level.
      Returns:
      The camera zoom level.

    • isCameraChanged

      public boolean isCameraChanged()
      Returns the state of the camera changed flag.
      Returns:
      True if camera has changed since the last frame.

    • getRotation

      public float getRotation()
      Returns the camera rotation angle.
      Returns:
      The camera rotation angle in degrees.

    • getRenderZoom

      public float getRenderZoom()
      The zoom the RENDERER works in: the reported zoom plus Options::ZoomOffset. vt sizes by
      `2^(zoom - tileZoom)`, so it needs the zoom the tiles were chosen for.
      Returns:
      The renderer's zoom level.

    • getZoom0Distance

      public float getZoom0Distance()
      Returns the distance between the focus and the camera position, when the zoom level is set to 0.
      This parameter depends on the screen size, DPI, tile draw size and field of view settings.
      Returns:
      The distance between focus to camera position, when zoom level = 0.

    • getWidth

      public int getWidth()
      Returns the width of the map screen.
      Returns:
      The map screen width.

    • getHeight

      public int getHeight()
      Returns the height of the map screen.
      Returns:
      The map screen height.

    • getAspectRatio

      public float getAspectRatio()
      Returns the aspect ratio of the map screen. Equal to width / height.
      Returns:
      The aspect ratio of the map screen.

    • getNear

      public float getNear()
      Returns the near plane distance.
      Returns:
      The new plane distance.

    • getFar

      public float getFar()
      Returns the far plane distance.
      Returns:
      The far plane distance.

    • setTerrainHeightRange

      public void setTerrainHeightRange(float minZ, float maxZ)
      Sets the terrain height range (in internal units). The range extends the
      near/far plane calculation so that displaced terrain is not clipped.
      Parameters:
      minZ - The minimum terrain height.
      maxZ - The maximum terrain height.

    • clearTerrainCameraReference

      public void clearTerrainCameraReference()
      Turns the terrain zoom bound off (no terrain, or a non-planar projection).

    • getTerrainMaxZoom

      public float getTerrainMaxZoom()
      Returns the maximum zoom allowed by the terrain clearance, or infinity when
      no terrain bound is active. Evaluated against the CURRENT camera state, so it
      carries no frame lag: zooming in by this delta lands the camera exactly on the
      clearance shell. Every zoom path (gesture, animation, kinetic fling, API) is
      clamped by it, which is what keeps the camera from being pushed into the
      terrain and then corrected back out - the correction/gesture fight that makes
      zooming jump back and forth. Below the current zoom when the camera is already
      under the shell: the bound then stops a zoom in, and MapRenderer's correction
      lifts the camera.
      Returns:
      The terrain-imposed maximum zoom.

    • getOrbitDistance

      public double getOrbitDistance(float zoom)
      Returns the camera-to-focus distance at the given zoom, what the zoom is calibrated on.
      Parameters:
      zoom - The zoom.
      Returns:
      The distance in internal units.

    • getFOVY

      public int getFOVY()
      Returns the vertical field of view angle.
      Returns:
      The vertical field of view angle in degrees.

    • getDPToPX

      public float getDPToPX()
      Returns a value that is used for converting display independent pixels (dp) to pixels (px).
      This values depends on the screen density.
      Returns:
      The dp to px value.

    • getDPI

      public float getDPI()
      Returns the dots per inch parameter of the screen.
      Returns:
      The screen DPI parameter.

    • getUnitToPXCoef

      public float getUnitToPXCoef()
      Returns the conversion ratio between internal map units and screen pixels. This parameter is dependent
      on the zoom level and other screen parameters.
      Returns:
      The conversion ratio between internal map units and screen pixels.

    • getUnitToDPCoef

      public float getUnitToDPCoef()
      Returns the conversion ratio between internal map units and screen density independent pixels (DP or DIP).
      This parameter is dependent on the zoom level, DPI and other screen parameters.
      Returns:
      The conversion ratio between internal map units and screen density independent pixels.

    • getLabelFrustum

      public SWIGTYPE_p_cglib__frustum3T_double_t getLabelFrustum()
      Returns the view frustum grown by the label padding band, the one tiles must reach for
      their labels to be placed before they scroll in. See vt::ViewState::labelPadding.
      Returns:
      The label view frustum.

    • getScreenWidth

      public int getScreenWidth()
      Returns the screen width.
      Returns:
      The current screen width.

    • getScreenHeight

      public int getScreenHeight()
      Returns the screen height.
      Returns:
      The current screen height.

    • getSkyHorizonNDC

      public float getSkyHorizonNDC()
      Returns the normalized device y below which no ray from the screen reaches the sky -
      the horizon, in other words, in the space the sky quad is drawn in. 1 when no sky is
      visible at all. Only meaningful when isSkyVisible() is true.
      Returns:
      The horizon's position in normalized device coordinates, -1 (bottom) to 1 (top).

    • calculateViewDistance

      public double calculateViewDistance(Options options)
      How far from the camera the map is drawn, in internal units - tangram's rule, scaled by
      TerrainOptions::ViewDistanceFactor. Both the far plane and the tile walk stop here, so
      the tiles fetched are exactly the tiles the frustum can show. 0 means "as far as the
      visible ground goes" (factor 0).
      Parameters:
      options - The options object.
      Returns:
      The view distance in internal units, or 0 if it is unbounded.

    • calculateCameraDistance

      public double calculateCameraDistance()
      The distance from the camera to the focus point - tangram's m_pos.z, which is what their
      near and far planes are built on. It is a function of the zoom alone, so the depth budget
      does not change with the terrain under the camera.
      Returns:
      The camera to focus distance in internal units.