Access and manipulate transformation matrices. More...

reme_error_t	reme_transform_set_predefined (reme_context_t c, reme_transform_t t, float *coordinates)
	Set the matrix to a predefined transform.

reme_error_t	reme_transform_look_at (reme_context_t c, const float eye, const float ref, const float up, float coordinates)
	Defines a viewing transformation.

reme_error_t	reme_transform_make_relative (reme_context_t c, const float a_t, const float b_t, float *c_t)
	Calculate the relative transform between two coordinate frames.

Detailed Description

Access and manipulate transformation matrices.

In the ReconstructMe SDK rigid transformations are represented using 4x4 floating point homogeneous matrices. The upper 3x3 part contains the rotation matrix. The last column contains the translation vector. The last row is constant.

| Rxx Rxy Rxz Tx |
| Ryx Ryy Ryz Ty |
| Rzx Rzy Rzz Tz |
|   0   0   0  1 |

The memory layout is row-major. Flattened to a one dimensional array the above matrix is transformed into

| Rxx Rxy Rxz Tx Ryx Ryy Ryz Ty Rzx Rzy Rzz Tz 0 0 0 1|

Coordinate systems are represented by 4x4 single precision floating point homogeneous matrices. The upper 3x3 part contains the basis vectors in columns, the last column contains the origin of the frame and the last row is constant.

Function Documentation

reme_error_t reme_transform_set_predefined	(	reme_context_t	c,
		reme_transform_t	t,
		float *	coordinates
	)

Set the matrix to a predefined transform.

Parameters

c	A valid context object
t	A predefined transform type
coordinates	A pointer to mutable Transform data.

Return values

REME_ERROR_SUCCESS	On success
REME_ERROR_UNSPECIFIED	On failure

Examples:: example_reconstructmesdk_memory_management.cpp, and example_reconstructmesdk_surface.cpp.

reme_error_t reme_transform_look_at	(	reme_context_t	c,
		const float *	eye,
		const float *	ref,
		const float *	up,
		float *	coordinates
	)

Defines a viewing transformation.

This method works similarily to gluLookAt. It defines a viewing transformation based on the eye coordinates, a viewing reference point and an up vector. This method simplifies specifying sensor positions (reme_sensor_set_position).

First, the view direction is vz is calculated by vz = ref - eye. This vector is normalized to unit length vz = vz / |vz| and becomes the z-vector of the viewing transformation. Next, the up vector is normalized to unit length up = up / |up|.

The cross product vx = -up x vz will become the x-axis of the viewing transformation after normalization vx = vx / |vx|.

Finally the cross product of vy = vz x vx defines the y-axis of the viewing transformation. The origin of the viewing transformation is set to the eye coordinates.

The final matrix becomes

| vx.x vy.x vz.x eye.x |
| vx.y vy.y vz.y eye.y |
| vx.z vy.z vz.z eye.z |
|    0    0    0     1 |

Parameters

c	A valid context object
eye	three dimensional vector defining the eye coordinates
ref	three dimensional vector defining the reference point coordinates
up	three dimensional vector defining the up vector
coordinates	A pointer to mutable Transform data.

Return values

REME_ERROR_SUCCESS	On success
REME_ERROR_UNSPECIFIED	On failure

Examples:: example_reconstructmesdk_sensor_printing.cpp.

reme_error_t reme_transform_make_relative	(	reme_context_t	c,
		const float *	a_t,
		const float *	b_t,
		float *	c_t
	)

Calculate the relative transform between two coordinate frames.

Given two coordinate frames, a_t and b_t in the same parental coordinate frame, calculate b_t with respect to a_t. The result is stored in c_t.

Parameters

c	A valid context object
a_t	A pointer to non mutable Transform data.
b_t	A pointer to non mutable Transform data.
c_t	A pointer to mutable Transform data.

Return values

REME_ERROR_SUCCESS	On success
REME_ERROR_UNSPECIFIED	On failure