I know. But that is not my question.

I'm specifically looking for what other information (besides x and y), are available (by default), from the object returned from $canvas->XEvent method in a mouse event callback. As in the OPs use: 

    $e = $canvas -> XEvent;
    $canv_x = $e->x;
    $canv_y = $e->y;

[download]

This has to be documented somewhere?

Looking again at the Tk:bind docs at the section entitled "BINDING CALLBACKS AND SUBSTITUTIONS", it appears that you can choose froma wide variety and formats, what information gets passed to the callback by using the Ev() function(?) when forming the bind. But this appears to involve yet more callbacks and and dynamic evaluations, which slows things down horribly--as if it wasn't slow enough anyway.

I was hoping to find that the default information supplied to a canvas mouse event callback included not just the window relative x/y, but also the canvas relative x/y. Performing the convesion isn't hard, but it involves yet more calls and just slows everything down again.

I'm not sure why I (or anyone) bother persisting with using this stuff--it's just painful.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^3: Tk Mandelbrot Fractal by BrowserUk
in thread Tk Mandelbrot Fractal by Melly

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