campitch

Set or query pitch angle of camera for geographic globe

Since R2020b

Syntax

campitch(g,pitch)

campitch(g,'auto')

campitch(g,'manual')

outPitch = campitch(g)

outPitch = campitch(___)

Description

Set Pitch and Mode

campitch(g,pitch) sets the pitch angle of the camera for the specified geographic globe. Setting the pitch angle tilts the camera up or down. For more information about how camera rotations affect your view of the globe, see How Camera Orientation Affects Globe View.

campitch(g,'auto') sets the camera pitch to automatic mode, enabling the geographic globe to determine the pitch angle based on plotted data. The mode defaults to automatic when you create a geographic globe. If you interact with the globe using your mouse, then the mode switches to automatic.

campitch(g,'manual') sets the camera pitch to manual mode, specifying that the geographic globe preserve the pitch angle when the plotted data changes. If you change the pitch angle using the campitch function, then the mode switches to manual.

Query Pitch

outPitch = campitch(g) returns the pitch angle of the camera.

outPitch = campitch(___) sets the pitch angle or mode and then returns the pitch angle of the camera. You can return the pitch angle using any combination of input arguments from the previous syntaxes.

Examples

Change Pitch Angle of Camera

Create a geographic globe. Position the camera near Mount Kilimanjaro by specifying a latitude, longitude, and ellipsoidal height. Set the pitch angle to 0 degrees, so that the camera points across the summit.

uif = uifigure;
g = geoglobe(uif);
campos(g,-3.1519,37.3561,5500)
campitch(g,0)

Tilt the camera up by increasing the pitch angle to 15 degrees.

campitch(g,15)

Animate Changes to Pitch Angle

Create a geographic globe. Position the camera near Mount Washington by specifying a latitude, longitude, and ellipsoidal height. Change the heading angle so that the camera faces the mountain. By default, the pitch angle is –90 degrees, so that the camera points at the ground.

uif = uifigure;
g = geoglobe(uif);

campos(g,44.2668,-71.3849,1757)
camheading(g,90)

Animate the view by incrementally changing the pitch angle. As the pitch angle increases, the camera changes from pointing at the ground to pointing at the sky. After the animation finishes, change the pitch angle to 0 degrees.

for pitch = -90:2:90
    campitch(g,pitch)
    drawnow
end
campitch(g,0)

Get Information About Camera View

Get the position and the heading, pitch, and roll angles of the camera. Use this information to control the view of a different geographic globe or to automate navigation.

Create a geographic globe. Navigate to an area of interest using your mouse or gestures. For this example, navigate to an area around Hawaii.

uif = uifigure;
g = geoglobe(uif);

Query the latitude, longitude, and ellipsoidal height of the camera, and assign each to a variable.

[camlat,camlon,camh] = campos(g)

camlat =

   18.3172


camlon =

 -155.5891


camh =

   6.2692e+04

Query the heading, pitch, and roll angles of the camera, and assign each to a variable.

heading = camheading(g)
pitch = campitch(g)
roll = camroll(g)

heading =

    3.7590


pitch =

  -29.9880


roll =

  359.9993

Use these values to control the view of a different geographic globe. For example, create a new geographic globe and programmatically set the view.

uif2 = uifigure;
g2 = geoglobe(uif2);
campos(g2,camlat,camlon,camh)
camheading(g2,heading)
campitch(g2,pitch)
camroll(g2,roll)

Preserve Camera View

Preserve the position and the heading, pitch, and roll angles of the camera by setting the camera modes to manual. If you do not set the camera modes to manual, then the camera view resets when you plot new data.

Import a sample route along roads in Massachusetts using the gpxread function. Create a geographic globe with a road map and no terrain data. Preserve the basemap and terrain settings by using the hold function. Then, navigate to an area near Eastern Massachusetts using your mouse.

track = gpxread("sample_tracks.gpx","Index",2);
lat = track.Latitude;
lon = track.Longitude;
height = track.Elevation;

uif = uifigure;
g = geoglobe(uif,"Basemap","streets","Terrain","none");
hold(g,"on")

Set the camera modes to manual and plot the data. Note that the camera position does not change.

campos(g,"manual")
camheight(g,"manual")
camheading(g,"manual")
campitch(g,"manual")
camroll(g,"manual")
geoplot3(g,lat,lon,height,"LineWidth",3)

Input Arguments

g — Geographic globe

GeographicGlobe object

Geographic globe, specified as a GeographicGlobe object.¹

pitch — Pitch angle of camera

–90 (default) | scalar

Pitch angle of the camera, specified as a scalar value in the range [–90, 90] degrees. By default, the pitch angle is –90 degrees, which means that camera points directly toward the surface of the globe.

More About

How Camera Orientation Affects Globe View

The values of the camera heading, pitch, and roll angles affect your view of a geographic globe. Mapping Toolbox™ references these values to the globe using a north-east-down (NED) coordinate system. As a result, when the heading, pitch, and roll angles of the camera are zero, the camera sits on a plane that is parallel to the tangent plane of the globe at the current latitude and longitude. For more information about NED coordinate systems, see Comparison of 3-D Coordinate Systems.

Change your view of a geographic globe by changing the heading, pitch, and roll angles of the camera:

• Heading — Rotate the camera about its z-axis, which shifts the view left or right. Move the view to the right by increasing the heading angle.

• Pitch — Rotate the camera about its y-axis, which tilts the view up or down. Tilt the view up by increasing the pitch angle.

• Roll — Rotate the camera about its x-axis, which spins the camera around its lens. Spin the view counterclockwise by increasing the roll angle.

Tips

• When the pitch angle is near –90 (the default) or 90 degrees, the camera loses one rotational degree of freedom. As a result, when you change the roll angle, the heading angle may change instead. This phenomenon is called gimbal lock. To avoid the effects of gimbal lock, call the camheading function instead of the camroll function.

Version History

Introduced in R2020b