tcamera

by Tim C. Lueth, SG-Lib Toolbox: SolidGeometry 5.6 - Visualization
Introduced first in SolidGeometry 1.0, Creation date: 2012-07-10, Last change: 2025-09-14

set camera to look on a given HT matrix using current zoom

See Also: camplot , camset , Tofgca , Tofcam

Example Illustration

Syntax

tcamera(T)

Input Parameter

T: HT matrix, the figure axes camera should look on

Examples

tcamera (eye(4));

Copyright 2012-2025 Tim C. Lueth. All rights reserved. The code is the property of Tim C. Lueth and may not be redistributed or modified without explicit written permission. This software may be used free of charge for academic research and teaching purposes only. Commercial use, redistribution, modification, or reverse engineering is strictly prohibited. Access to source code is restricted and granted only under specific agreements. For licensing inquiries or commercial use, please contact: Tim C. Lueth

Algorithm (Workflow)

This function, tcamera, is designed to adjust the camera view in a MATLAB figure to focus on a specified homogeneous transformation (HT) matrix. It is part of the SolidGeometry library and was created by Tim Lueth.

Input Parameters

T: A 4x4 homogeneous transformation matrix. The camera will be adjusted to look at the position and orientation defined by this matrix.
varargin: An optional parameter that can be used to specify additional arguments. In this function, it is used to potentially override the default camera distance.

Algorithm Steps

Extract the z-axis direction vector from the HT matrix T using ez = T(1:3,3);. This vector represents the direction the camera should face.
Extract the translation vector (position) from the HT matrix T using tp = T(1:3,4);. This vector represents the point the camera should target.
Retrieve the current camera target and position from the current axes using get(gca,'CameraTarget') and get(gca,'CameraPosition').
Calculate the distance d between the current camera position and target using norm(cp-ct). This distance is used to maintain the current zoom level.
Use the function getfuncparams to potentially override the default distance d with a value from varargin if provided.
Set the new camera target to the position tp using set(gca, 'CameraTarget',tp');.
Set the new camera position to be d units away from tp in the direction of ez using set(gca, 'CameraPosition',tp'+d*ez');.

This function effectively repositions and reorients the camera in a MATLAB figure to focus on a specified transformation matrix, maintaining the current zoom level unless overridden by additional parameters.

Algorithm explaination created using ChatGPT on 2025-08-18 22:30. (Please note: No guarantee for the correctness of this explanation)

Last html export of this page out of FM database by TL: 2025-09-21