src/camera.c File Reference

Code for managing a camera. More...

#include "camera.h"
#include <stdlib.h>
#include <math.h>

Data Structures
struct	_camera
	Internal storage for a camera. More...
Functions
void	_matrix4_product (float *result, float *A, float *B)
	An internal function that calculates a matrix product.
camera_t *	camera_create ()
	Creates a new camera object.
void	camera_destroy (camera_t *c)
	Cleans up a camera object.
void	camera_reset (camera_t *cam)
	Resets the position and rotation of the camera to default.
void	camera_translate (camera_t *cam, float x, float y, float z)
	Translate the camera.
void	camera_rotate (camera_t *cam, float theta, float x, float y, float z)
	Rotates the camera.
const float *	camera_get_matrix (camera_t *cam)
	Returns the matrix representation of the camera.
float *	camera_get_inverse_rotation_matrix (camera_t *cam)
	Returns a new matrix representing the inverse of the camera rotation.
void	camera_set_position (camera_t *cam, float x, float y, float z)
	Sets the camera's position in absolute coordinants.

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Detailed Description

Code for managing a camera.

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Function Documentation

void _matrix4_product	(	float *	result,
		float *	A,
		float *	B
	)

An internal function that calculates a matrix product.

Parameters:

[out]	result	The result is stored here. It must be an array of length 16.
[in]	A	The matrix on the left side of the multiplication.
[in]	B	The matrix on the right side of the multiplication.

camera_t* camera_create

(

void

)

Creates a new camera object.

The camera should be cleaned up with camera_destroy. The camera is set to the default position.

Returns:

A pointer to the new camera

void camera_destroy

(

camera_t *

cam

)

Cleans up a camera object.

Frees the memory used by a camera object.

Parameters:

[in]

cam

The camera to destroy.

float* camera_get_inverse_rotation_matrix

(

camera_t *

cam

)

Returns a new matrix representing the inverse of the camera rotation.

This array must be subsequently be freed!

Parameters:

[in]

cam

The camera to get the inverse from.

Returns:

A pointer to an array representing the 4x4 homogoneous matrix.

const float* camera_get_matrix

(

camera_t *

cam

)

Returns the matrix representation of the camera.

Parameters:

[in]

cam

The camera to get the matrix for.

Returns:

The homogenous matrix representing the transform.

void camera_reset

(

camera_t *

cam

)

Resets the position and rotation of the camera to default.

The default position is at the origin, looking in the negative z direction.

Parameters:

[in]

cam

The camera to reset.

void camera_rotate	(	camera_t *	cam,
		float	theta,
		float	x,
		float	y,
		float	z
	)

Rotates the camera.

Rotates the camera around the specified axis.

Parameters:

[in]	cam	The camera to rotate.
[in]	theta	The angle to rotate through (in radians).
[in]	x	The component of the axis of rotation in the x direction.
[in]	y	The component of the axis of rotation in the y direction.
[in]	z	The component of the axis of rotation in the z direction.

void camera_set_position	(	camera_t *	cam,
		float	x,
		float	y,
		float	z
	)

Sets the camera's position in absolute coordinants.

Parameters:

[in]	cam	The camera to set the position of.
[in]	x	The x coordinant of the new position.
[in]	y	The y coordinant of the new position.
[in]	z	The z coordinant of the new position.

void camera_translate	(	camera_t *	cam,
		float	x,
		float	y,
		float	z
	)

Translate the camera.

Moves the camera to (x, y, z), in the frame of reference of the camera.

Parameters:

[in]	cam	The camera to move.
[in]	x	The x-coordinant to move to.
[in]	y	The y-coordinant to move to.
[in]	z	The z-coordinant to move to.