gluPerspective function

The gluPerspective function sets up a perspective projection matrix.

Syntax

void WINAPI gluPerspective(
   GLdouble fovy,
   GLdouble aspect,
   GLdouble zNear,
   GLdouble zFar
);

Parameters

fovy

The field of view angle, in degrees, in the y-direction.

aspect

The aspect ratio that determines the field of view in the x-direction. The aspect ratio is the ratio of x (width) to y (height).

zNear

The distance from the viewer to the near clipping plane (always positive).

zFar

The distance from the viewer to the far clipping plane (always positive).

Return value

This function does not return a value.

Remarks

The gluPerspective function specifies a viewing frustum into the world coordinate system. In general, the aspect ratio in gluPerspective should match the aspect ratio of the associated viewport. For example, aspect = 2.0 means the viewer's angle of view is twice as wide in x as it is in y. If the viewport is twice as wide as it is tall, it displays the image without distortion.

The matrix generated by gluPerspective is multiplied by the current matrix, just as if glMultMatrix were called with the generated matrix. To load the perspective matrix onto the current matrix stack instead, precede the call to gluPerspective with a call to glLoadIdentity.

Requirements

See also

glFrustum

glLoadIdentity

glMultMatrix

gluOrtho2D