%
%
%  Camera Set Angle Function for Imaris
%
%  Copyright Bitplane AG 2006
%
%
%  Installation:
%
%  - Copy this file into the XTensions folder in the Imaris installation directory
%  - You will find this function in the Image Processing menu
%
%    <CustomTools>
%      <Menu>
%       <Submenu name="Camera Functions">
%        <Item name="Set The Angle Of The Camera" icon="Matlab" tooltip="Set the angle of the camera.">
%          <Command>Matlab::BPCameraSetAngle(%i)</Command>
%        </Item>
%       </Submenu>
%      </Menu>
%    </CustomTools>
% 
%
%  Description:
%   
%   The angle of the camera is defined using the 
%       [Azimuth, Elevation, Angle] coordinates.
%   The camera is rotated around axis Y by Angle, then around axis X by 
%       Elevation, then around axis Y by Azimuth.
%   Coordinates can be ambiguous: Different Azimuth, Elevation, Angle can
%       determine the same camera orientation.
%   The user can specify the coordinates through 3 sliders. 
%
%

function BPCameraSetAngle(aImarisApplicationID)

global vImarisApplication;
global vSliderAzimuth vSliderElevation vSliderAngle;
global vEditAzimuth vEditElevation vEditAngle;

% slider callbacks
if aImarisApplicationID==-1
    clear global vImarisApplication;
    clear global vSliderAzimuth vSliderElevation vSliderAngle;
    clear global vEditAzimuth vEditElevation vEditAngle;
    return;
elseif aImarisApplicationID==-2
    SliderMove;
    return;
elseif aImarisApplicationID==-3
    EditChange;
    return;
elseif aImarisApplicationID==-4
    ButtonPush;
    return;
end

% connect to Imaris Com interface
if ~isa(aImarisApplicationID, 'COM.Imaris_Application')
  vImarisServer = actxserver('ImarisServer.Server');
  vImarisApplication = vImarisServer.GetObject(aImarisApplicationID);
else
  vImarisApplication = aImarisApplicationID;
end

uicontrol('Style', 'text', 'String', 'Angle', 'Position', [10,70,90,20]);
vEditAngle = uicontrol('Style', 'edit', 'String', '0', 'Position', [410,70,90,20], ...
    'Callback', 'BPCameraSetAngle(-3)');
vSliderAngle = uicontrol('Style', 'slider', 'Position', [100,70,300,20], ...
    'Min', -180, 'Max', 180, 'Value', 0, 'SliderStep', [0.01,0.1], ...
    'Callback', 'BPCameraSetAngle(-2)');

uicontrol('Style', 'text', 'String', 'Elevation', 'Position', [10,40,90,20]);
vEditElevation = uicontrol('Style', 'edit', 'String', '0', 'Position', [410,40,90,20], ...
    'Callback', 'BPCameraSetAngle(-3)');
vSliderElevation = uicontrol('Style', 'slider', 'Position', [100,40,300,20], ...
    'Min', -180, 'Max', 180, 'Value', 0, 'SliderStep', [0.01,0.1], ...
    'Callback', 'BPCameraSetAngle(-2)');

uicontrol('Style', 'text', 'String', 'Azimuth', 'Position', [10,10,90,20])
vEditAzimuth = uicontrol('Style', 'edit', 'String', '0', 'Position', [410,10,90,20], ...
    'Callback', 'BPCameraSetAngle(-3)');
vSliderAzimuth = uicontrol('Style', 'slider', 'Position', [100,10,300,20], ...
    'Min', -180, 'Max', 180, 'Value', 0,  'SliderStep', [0.01,0.1], ...
    'Callback', 'BPCameraSetAngle(-2)');

uicontrol('Style', 'pushbutton', 'String', 'Get angles from Imaris', ...
    'Position', [320,100,180,25], 'Callback', 'BPCameraSetAngle(-4)', ...
    'DeleteFcn', 'BPCameraSetAngle(-1)');

vWindow = get(vSliderAzimuth, 'Parent');
vWindowPosition = get(vWindow, 'Position');
vWindowPosition(3:4) = [510, 130];
set(vWindow, 'Position', vWindowPosition);


function SliderMove()
% slider
global vSliderAzimuth vSliderElevation vSliderAngle;
global vEditAzimuth vEditElevation vEditAngle;

vAngle = get(vSliderAngle, 'Value');
vElevation = get(vSliderElevation, 'Value');
vAzimuth = get(vSliderAzimuth, 'Value');

set(vEditAngle, 'String', num2str(vAngle));
set(vEditElevation, 'String', num2str(vElevation));
set(vEditAzimuth, 'String', num2str(vAzimuth));

CameraSetAngle(vAzimuth, vElevation, vAngle); 


function EditChange()
% edit
global vSliderAzimuth vSliderElevation vSliderAngle;
global vEditAzimuth vEditElevation vEditAngle;

vAngle = str2double(get(vEditAngle, 'String'));
vElevation = str2double(get(vEditElevation, 'String'));
vAzimuth = str2double(get(vEditAzimuth, 'String'));

while vAngle>180, vAngle = vAngle-360; end;
while vAngle<-180, vAngle = vAngle+360; end;
while vElevation>180, vElevation = vElevation-360; end;
while vElevation<-180, vElevation = vElevation+360; end;
while vAzimuth>180, vAzimuth = vAzimuth-360; end;
while vAzimuth<-180, vAzimuth = vAzimuth+360; end;

set(vSliderAngle, 'Value', vAngle);
set(vSliderElevation, 'Value', vElevation);
set(vSliderAzimuth, 'Value', vAzimuth);

CameraSetAngle(vAzimuth, vElevation, vAngle); 


function ButtonPush()
% get
global vImarisApplication;
global vSliderAzimuth vSliderElevation vSliderAngle;
global vEditAzimuth vEditElevation vEditAngle;

% get the camera
vCamera = vImarisApplication.mSurpassCamera;

[vOrientationX, vOrientationY, vOrientationZ, vCameraAngle] = vCamera.GetOrientationAxisAngle;
vAxis = [vOrientationX; vOrientationY; vOrientationZ];
vAxis = vAxis/norm(vAxis);

vDirectionX = RotateVA([1;0;0],vAxis,vCameraAngle);
vDirectionY = RotateVA([0;1;0],vAxis,vCameraAngle);
% vDirectionZ = RotateVA([0;0;1],vAxis,vCameraAngle);

% computes the angle
if vDirectionY(2)==1
    % ambiguous situation
    vAngle = acos(vDirectionX(1));
    if vDirectionX(1)<0
       vAngle = -vAngle;
    end
else
    vAngle = acos(vDirectionY(3)/norm(vDirectionY([1,3])));
    if vDirectionY(1)<0
       vAngle = -vAngle;
    end
end

vDirectionX = RotateVA(vDirectionX,[0;1;0],-vAngle);
vDirectionY = RotateVA(vDirectionY,[0;1;0],-vAngle);

% computes the elevation
vElevation = acos(vDirectionY(2));
if vDirectionY(3)<0
    vElevation = -vElevation;
end

vDirectionX = RotateVA(vDirectionX,[1;0;0],-vElevation);

% computes the azimuth
vAzimuth = acos(vDirectionX(1));
if vDirectionX(3)>0
    vAzimuth = -vAzimuth;
end


% converts from radiants to degrees
vAngle = vAngle*180/pi;
vElevation = vElevation*180/pi;
vAzimuth = vAzimuth*180/pi;

set(vSliderAngle, 'Value', vAngle);
set(vSliderElevation, 'Value', vElevation);
set(vSliderAzimuth, 'Value', vAzimuth);
set(vEditAngle, 'String', num2str(vAngle));
set(vEditElevation, 'String', num2str(vElevation));
set(vEditAzimuth, 'String', num2str(vAzimuth));


function CameraSetAngle(vAzimuth, vElevation, vAngle) 
% set
global vImarisApplication;

% converts from degrees to radiants
vAzimuth = vAzimuth*pi/180;
vElevation = vElevation*pi/180;
vAngle = vAngle*pi/180;

% get the camera
vCamera = vImarisApplication.mSurpassCamera;

[vPositionX, vPositionY, vPositionZ] = vCamera.GetPosition;
vPosition = [vPositionX; vPositionY; vPositionZ];
[vOrientationX, vOrientationY, vOrientationZ, vCameraAngle] = vCamera.GetOrientationAxisAngle;
vAxis = [vOrientationX; vOrientationY; vOrientationZ];
vAxis = vAxis/norm(vAxis);

vFocus = vCamera.mFocus;

vDirection = RotateVA([0;0;1],vAxis,vCameraAngle);

vCenter = vPosition-vFocus*vDirection;

% computes the coordinates of the axis after the desired rotations
vAxis = eye(3);
vNewAxisX = RotateVA(vAxis(:,1),[0;1;0],vAzimuth);
vNewAxisX = RotateVA(vNewAxisX,[1;0;0],vElevation);
vNewAxisX = RotateVA(vNewAxisX,[0;1;0],vAngle);

vNewAxisY = RotateVA(vAxis(:,2),[0;1;0],vAzimuth);
vNewAxisY = RotateVA(vNewAxisY,[1;0;0],vElevation);
vNewAxisY = RotateVA(vNewAxisY,[0;1;0],vAngle);

vNewAxisZ = RotateVA(vAxis(:,3),[0;1;0],vAzimuth);
vNewAxisZ = RotateVA(vNewAxisZ,[1;0;0],vElevation);
vNewAxisZ = RotateVA(vNewAxisZ,[0;1;0],vAngle);

vNewAxis = [vNewAxisX,vNewAxisY,vNewAxisZ];
vDelta = vNewAxis-vAxis;

% computes the axis of rotation
% find and discard the less significant dimension
% cross(vDelta(:,1),vDelta(:,2))==cross(vDelta(:,2),vDelta(:,3))==
%   cross(vDelta(:,3),vDelta(:,1)), for ~(vDelta(:,i)==0)
[vMin, vDim] = min(sum(vDelta.^2));
vAxis = vDelta(:,[1:vDim-1,vDim+1:3]);
vAxis = cross(vAxis(:,1),vAxis(:,2));
if norm(vAxis)>0
    vAxis = vAxis/norm(vAxis);
end

% computes the angle using the most significant dimension
[vMax, vDim] = max(sum(vDelta.^2));
vStart = [0;0;0];
vStart(vDim) = 1;
vEnd = vNewAxis(:,vDim);
vStartProjected = dot(vStart,vAxis)*vAxis;
vEndProjected = dot(vEnd,vAxis)*vAxis;

vStart = vStart-vStartProjected;
vEnd = vEnd-vEndProjected;
vCameraAngle = acos(dot(vStart,vEnd)/(norm(vStart)*norm(vEnd)));

if dot(vAxis,cross(vStart,vEnd))<0
    vCameraAngle = -vCameraAngle;
end

vDirection = RotateVA([0;0;1],vAxis,vCameraAngle);

vPos = vCenter+vFocus*vDirection;
vCamera.SetPosition(vPos(1), vPos(2), vPos(3));
vCamera.SetOrientationAxisAngle(vAxis(1), vAxis(2), vAxis(3), vCameraAngle);


function aResult = RotateVA(aVector, aAxis, aAngle)
% rotate aVector around aAxis by aAngle
aResult = aVector .* cos(aAngle) + aAxis.*dot(aAxis,aVector) .* (1-cos(aAngle)) + ...
    cross(aAxis,aVector) .* sin(aAngle);