#pragma rtGlobals=3
#pragma version = 2.0
#pragma IgorVersion = 6.1
#pragma ModuleName = PearlVectorOperations

// author: matthias.muntwiler@psi.ch
// Copyright (c) 2011-13 Paul Scherrer Institut
// $Id$

function rotate2d_x(xx, yy, angle)
	// rotates a 2D cartesian vector and returns its x component
	variable xx, yy
	variable angle // rotation angle in degrees
	
	return xx * cos(angle * pi / 180) - yy * sin(angle * pi / 180)
end

function rotate2d_y(xx, yy, angle)
	// rotates a 2D cartesian vector and returns its y component
	variable xx, yy
	variable angle // rotation angle in degrees
	
	return xx * sin(angle * pi / 180) + yy * cos(angle * pi / 180)
end

function /wave create_rotation_matrix_free()
	// creates a matrix which represents a 3-vector rotation
	// the matrix is initialized as identity
	
	make /n=(3,3)/free matrix
	matrix = p == q // identity
	return matrix
end

function /wave set_rotation_x(matrix, angle)
	// calculates a matrix representing a 3-vector rotation around the x axis
	wave matrix // rotation matrix
	variable angle // rotation angle in degrees
	
	variable si = sin(angle * pi / 180)
	variable co = cos(angle * pi / 180)
	
	matrix[1][1] = co
	matrix[2][2] = co
	matrix[2][1] = si
	matrix[1][2] = -si

	return matrix
end

function /wave set_rotation_y(matrix, angle)
	// calculates a matrix representing a 3-vector rotation around the y axis
	wave matrix // rotation matrix
	variable angle // rotation angle in degrees
	
	variable si = sin(angle * pi / 180)
	variable co = cos(angle * pi / 180)
	
	matrix[0][0] = co
	matrix[2][2] = co
	matrix[0][2] = si
	matrix[2][0] = -si

	return matrix
end

function /wave set_rotation_z(matrix, angle)
	// calculates a matrix representing a 3-vector rotation around the z axis
	wave matrix // rotation matrix
	variable angle // rotation angle in degrees
	
	variable si = sin(angle * pi / 180)
	variable co = cos(angle * pi / 180)
	
	matrix[0][0] = co
	matrix[1][1] = co
	matrix[1][0] = si
	matrix[0][1] = -si

	return matrix
end

function rotate_x_wave(inout, angle)
	// rotates a wave of 3-vectors about the x axis
	wave inout // wave with dimensions (3, N), N >= 1, (x, y, z)
		// result will be in same wave
	variable angle // rotation angle in degrees

	wave m_rotation_x = create_rotation_matrix_free()
	make /n=3/d/free w_temp_rotate_x
	variable ivec, nvec
	nvec = max(DimSize(inout, 1), 1)
	for (ivec = 0; ivec < nvec; ivec += 1)
		set_rotation_x(m_rotation_x, angle)
		w_temp_rotate_x = inout[p][ivec]
		matrixop /free w_temp_rotate_x_result = m_rotation_x x w_temp_rotate_x
		inout[][ivec] = w_temp_rotate_x_result[p]
	endfor	
end

function rotate_y_wave(inout, angle)
	// rotates a wave of 3-vectors about the y axis
	wave inout // wave with dimensions (3, N), N >= 1, (x, y, z)
		// result will be in same wave
	variable angle // rotation angle in degrees

	wave m_rotation_y = create_rotation_matrix_free()
	make /n=3/d/free w_temp_rotate_y
	variable ivec, nvec
	nvec = max(DimSize(inout, 1), 1)
	for (ivec = 0; ivec < nvec; ivec += 1)
		set_rotation_y(m_rotation_y, angle)
		w_temp_rotate_y = inout[p][ivec]
		matrixop /free w_temp_rotate_y_result = m_rotation_y x w_temp_rotate_y
		inout[][ivec] = w_temp_rotate_y_result[p]
	endfor	
end

function rotate_z_wave(inout, angle)
	// rotates a wave of 3-vectors about the z axis
	wave inout // wave with dimensions (3, N), N >= 1, (x, y, z)
		// result will be in same wave
	variable angle // rotation angle in degrees

	wave m_rotation_z = create_rotation_matrix_free()
	make /n=3/d/free w_temp_rotate_z
	variable ivec, nvec
	nvec = max(DimSize(inout, 1), 1)
	for (ivec = 0; ivec < nvec; ivec += 1)
		set_rotation_z(m_rotation_z, angle)
		w_temp_rotate_z = inout[p][ivec]
		matrixop /free w_temp_rotate_z_result = m_rotation_z x w_temp_rotate_z
		inout[][ivec] = w_temp_rotate_z_result[p]
	endfor	
end