在OCTAVE中获取鼠标位置

Question

I am using OCTAVE on my PC for image processing and display. I am reading in a .pgl file and converting it from rgb to gray to obtain a simple 2D array. I then display this using imagesc(). What I'd like to do is use the mouse to click on a particular part of the image and return where the mouse was clicked in the array ((x,y) coordinates). I've tried using ginput() which I think should work if I understand the documentation correctly. But I can't get it to work. Usually I have to control C out once I type in [x,y] = ginput(1), for example, because the prompt never returns in my input window no matter how many mouse clicks I do in the display (or returns in the input window - I have to control C out). First is this do-able? or am I attempting something OCTAVE just can't do? If so, how?

Answer 1

This should work with ginput and the FLTK toolkit. What version of Octave are you using on which OS? To make sure you are using FLTK toolkit use

close all
graphics_toolkit fltk

at the beginning of your script.

Answer 2

The thing to remember with ginput() is that after clicking with the mouse in the plot window, you have to hit return key on the keyboard if the n parameter is not stated. After the return, the coordinates will be returned in the x,y vars. Also the button used to click will be returned when called with [x,y,buttons]=ginput(n). The 'n' argument controls the number of clicks to watch for before recording the coords. Works well in Octave 4.0.1.