<html> <head> <meta content="text/html; charset=UTF-8" http-equiv="Content-Type"> </head> <body bgcolor="#FFFFFF" text="#000000"> Excluding only the mouse events from triggering a refresh would probably be the most elegant solution. My canvas should only ever listen to a timer, though, so they might as well share some insider information: #lang racket/gui (require sgl) (define c% (class canvas% (inherit with-gl-context swap-gl-buffers refresh) (define asked-nicely? #f) (define (please) (set! asked-nicely? #t)) (define (thank-you) (set! asked-nicely? #f)) (define/public (please-refresh) (please) (refresh)) (define/override (on-paint) (when asked-nicely? (with-gl-context (lambda () (gl-clear-color (random) (random) (random) 1) (gl-clear 'color-buffer-bit) (swap-gl-buffers) (gl-flush))) (thank-you))) (super-new (style '(gl))))) (define t% (class timer% (define/override (notify) (send c please-refresh)) (super-new))) (define f (new frame% [label ""] [width 100] [height 100])) (define c (new c% [parent f])) (define t (new t% [interval 1000])) (send f show #t) <div class="moz-cite-prefix">On 12.02.13 20:04, Robby Findler wrote: </div> <blockquote cite="mid:CAL3TdOOoZkoX-ObhFuOvH6qpb6PTJAgy6JnfQfiYPcWH36=K8w@mail.gmail.com" type="cite"> <div dir="ltr">Could you work around this by tracking mouse movements and, when you see a refresh call that comes with a mouse movement doing something different than drawing? (I guess you'd need to set a timer that expired in a short time and refresh then, just in case it was a "real" refresh, but at least you could work around the performance issue.) <div> </div> <div style="">Robby</div> </div> <div class="gmail_extra"> <div class="gmail_quote">On Tue, Feb 12, 2013 at 1:02 PM, Robby Findler <<a moz-do-not-send="true" href="mailto:robby@eecs.northwestern.edu" target="_blank">robby@eecs.northwestern.edu</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <div dir="ltr">I was using os x 10.7.5 (and saw the same flashing).</div> <div class="HOEnZb"> <div class="h5"> <div class="gmail_extra"> <div class="gmail_quote">On Tue, Feb 12, 2013 at 12:59 PM, Philipp Dikmann <<a moz-do-not-send="true" href="mailto:philipp@dikmann.de" target="_blank">philipp@dikmann.de</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">The OS here is Mac OS 10.6.8, running Racket 5.3.1 - so I guess its an issue with the OpenGL implementation. Thanks for taking a look, though :) <div> <div> On 12.02.13 19:37, Michael Wilber wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> Your OpenGL example still doesn't flash for me when I move the mouse over it, on 64-bit linux. It does, however, flash when I change window focus... for some reason? What OS are you using? Philipp Dikmann <<a moz-do-not-send="true" href="mailto:philipp@dikmann.de" target="_blank">philipp@dikmann.de</a>> writes: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> I'm sorry, I should have been more specific – it happens when using a gl-enabled canvas (example below). I hope that does not turn it into a dragons' den? ;) Philipp #lang racket/gui (require sgl) (define c% (class canvas% (inherit with-gl-context swap-gl-buffers) (define/override (on-paint) (with-gl-context (lambda () (gl-clear-color (random) (random) (random) 1) (gl-clear 'color-buffer-bit) (swap-gl-buffers) (gl-flush)))) (super-new (style '(gl no-autoclear))))) (define f (new frame% [label ""] [width 100] [height 100])) (define c (new c% [parent f])) (send f show #t) On 11.02.13 22:39, Robby Findler wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> I don't think it does that. The program below, at least for me, doesn't do crazy colors when I move the mouse around (it does when resizing, tho). Robby #lang racket/gui (define c% (class canvas% (inherit get-client-size get-dc) (define/override (on-paint) (define-values (w h) (get-client-size)) (define dc (get-dc)) (define c (make-object color% (random 255) (random 255) (random 255))) (send dc set-brush c 'solid) (send dc set-pen "black" 1 'transparent) (send dc draw-ellipse 0 0 w h)) (super-new))) (define f (new frame% [label ""] [width 100] [height 100])) (define c (new c% [parent f])) (send f show #t) On Mon, Feb 11, 2013 at 9:41 AM, Philipp Dikmann <<a moz-do-not-send="true" href="mailto:philipp@dikmann.de" target="_blank">philipp@dikmann.de</a> <mailto:<a moz-do-not-send="true" href="mailto:philipp@dikmann.de" target="_blank">philipp@dikmann.de</a>>> wrote: It appears that the GUI canvas% refreshes itself whenever it receives a mouse-event%. I intend to refresh the canvas at a steady pace (using a timer%) and independently of any mouse-events instead. Is there a reasonable way to suppress the default behavior? Thanks for your time, Philipp ____________________ Racket Users list: <a moz-do-not-send="true" href="http://lists.racket-lang.org/users" target="_blank">http://lists.racket-lang.org/users</a> </blockquote> ____________________ Racket Users list: <a moz-do-not-send="true" href="http://lists.racket-lang.org/users" target="_blank">http://lists.racket-lang.org/users</a> </blockquote> </blockquote> </div> </div> </blockquote> </div> </div> </div> </div> </blockquote> </div> </div> </blockquote> </body> </html>