com.io7m.jcanephora.core

Interface JCGLProjectionMatricesType

All Known Implementing Classes:

JCGLProjectionMatrices

public interface JCGLProjectionMatricesType

Functions for creating projection matrices.

Method Summary

Modifier and Type	Method and Description
void	makeFrustumProjection(com.io7m.jtensors.MatrixWritable4x4FType matrix, double x_min, double x_max, double y_min, double y_max, double z_near, double z_far) Calculate a matrix that produces a perspective projection.
void	makeOrthographicProjection(com.io7m.jtensors.MatrixWritable4x4FType matrix, double x_min, double x_max, double y_min, double y_max, double z_near, double z_far) Calculate a projection matrix that produces an orthographic projection based on the given clipping plane coordinates.
void	makePerspectiveProjection(com.io7m.jtensors.MatrixWritable4x4FType matrix, double z_near, double z_far, double aspect, double horizontal_fov) Calculate a matrix that will produce a perspective projection based on the given view frustum parameters, the aspect ratio of the viewport and a given horizontal field of view in radians.

Method Detail

makeFrustumProjection

void makeFrustumProjection(com.io7m.jtensors.MatrixWritable4x4FType matrix,
                           double x_min,
                           double x_max,
                           double y_min,
                           double y_max,
                           double z_near,
                           double z_far)

Calculate a matrix that produces a perspective projection. The (x_min, y_min, z_near) and (x_max, y_max, z_near) parameters specify the points on the near clipping plane that are mapped to the lower-left and upper-right corners of the window, respectively, assuming that the eye is located at (0, 0, 0). The z_far parameter specifies the location of the far clipping plane.

Note that iff z_far >= Double.POSITIVE_INFINITY, the function produces an "infinite projection matrix", suitable for use in code that deals with shadow volumes.

See GPU Gems

Parameters:

x_min - The minimum X clip plane.

x_max - The maximum X clip plane.

y_min - The minimum Y clip plane.

y_max - The maximum Y clip plane.

z_near - The near Z clip plane.

z_far - The far Z clip plane.

matrix - The matrix to which values will be written.

makeOrthographicProjection

void makeOrthographicProjection(com.io7m.jtensors.MatrixWritable4x4FType matrix,
                                double x_min,
                                double x_max,
                                double y_min,
                                double y_max,
                                double z_near,
                                double z_far)

Calculate a projection matrix that produces an orthographic projection based on the given clipping plane coordinates.

Parameters:

x_min - The left clipping plane coordinate.

x_max - The right clipping plane coordinate.

y_min - The bottom clipping plane coordinate.

y_max - The top clipping plane coordinate.

z_near - The near clipping plane coordinate.

z_far - The far clipping plane coordinate.

matrix - The matrix to which values will be written.

makePerspectiveProjection

void makePerspectiveProjection(com.io7m.jtensors.MatrixWritable4x4FType matrix,
                               double z_near,
                               double z_far,
                               double aspect,
                               double horizontal_fov)

Calculate a matrix that will produce a perspective projection based on the given view frustum parameters, the aspect ratio of the viewport and a given horizontal field of view in radians. Note that fov_radians represents the full horizontal field of view: the angle at the base of the triangle formed by the frustum on the x/z plane.

Note that iff z_far >= Double.POSITIVE_INFINITY, the function produces an "infinite projection matrix", suitable for use in code that deals with shadow volumes.

See GPU Gems

Parameters:

z_near - The near clipping plane coordinate.

z_far - The far clipping plane coordinate.

aspect - The aspect ratio of the viewport; the width divided by the height. For example, an aspect ratio of 2.0 indicates a viewport twice as wide as it is high.

horizontal_fov - The horizontal field of view in radians.

matrix - The matrix to which values will be written.