Yes! Thank you. Dex
________________________________ From: Matthew Flatt <mfl...@cs.utah.edu> Sent: Friday, April 16, 2021 3:26:19 PM To: Dexter Lagan <dexterla...@gmail.com> Cc: Racket Users <racket-users@googlegroups.com> Subject: Re: [racket-users] Wheel / touchpad / trackpoint accuracy/speed scrolling fix for DrRacket Oh, I think I finally get it. The problem is that the leftover amount is returned by `gen-wheels`. With scaling by `wheel-scale`, the returned leftover has been scaled --- but when the leftover is passed back to `gen-wheels` later, it gets scaled again. Applying the scale to `WHEEL_DELTA` instead of `amt` solves the problem, because then the returned leftover amount is on the same scale as the argument amount. Thanks for working through this, and I'll push this change! At Fri, 16 Apr 2021 01:23:16 -0700 (PDT), Dexter Lagan wrote: > Hi Matt, > > This works because when amt is smaller than WHEEL_DELTA, the amt value is > used directly, see first branch of the cond : > > (cond > * [((abs amt) . < . WHEEL_DELTA_S)* > (case wheel-steps-mode > [(one integer) amt] > [(fraction) > (unless (zero? amt) > (do-key w msg down lParam #f #f void (/ amt > (exact->inexact WHEEL_DELTA_S)))) > 0.0])] > > I logged the values with and without the fix. In both cases, I scrolled > slowly down : > > WHEEL_DELTA_S:120 > wheel-scale:4 > amt:-8 > > WHEEL_DELTA_S:120 > wheel-scale:4 > amt:-40 > > WHEEL_DELTA_S:120 > wheel-scale:4 > amt:-168 > > WHEEL_DELTA_S:120 > wheel-scale:4 > amt:-48 > > WHEEL_DELTA_S:120 > wheel-scale:4 > amt:-200 > > WHEEL_DELTA_S:120 > wheel-scale:4 > amt:-80 > > WHEEL_DELTA_S:120 > wheel-scale:4 > amt:-332 > > WHEEL_DELTA_S:120 > wheel-scale:4 > amt:-92 > > WHEEL_DELTA_S:120 > wheel-scale:4 > amt:-376 > > Amt is often larger than WHEEL_DELTA. After applying the changes > (dividing WHEEL-DELTA and removing the wheel-scale mul) : > > WHEEL_DELTA_S:30 > wheel-scale:4 > amt:-2 > > WHEEL_DELTA_S:30 > wheel-scale:4 > amt:-4 > > WHEEL_DELTA_S:30 > wheel-scale:4 > amt:-6 > > WHEEL_DELTA_S:30 > wheel-scale:4 > amt:-8 > > WHEEL_DELTA_S:30 > wheel-scale:4 > amt:-11 > > WHEEL_DELTA_S:30 > wheel-scale:4 > amt:-13 > > WHEEL_DELTA_S:30 > wheel-scale:4 > amt:-15 > > WHEEL_DELTA_S:30 > wheel-scale:4 > amt:-17 > > WHEEL_DELTA_S:30 > wheel-scale:4 > amt:-19 > > WHEEL_DELTA_S:30 > wheel-scale:4 > amt:-22 > > > Amt is never above WHEEL_DELTA, which triggers only the first branch of the > cond. The amt value is used with no adjustment, hense the precise behaviour. > > Dex > > On Thursday, April 15, 2021 at 1:49:53 PM UTC+2 Matthew Flatt wrote: > > > Thanks for this summary! But I remain puzzled... > > > > As I understand it, `wheel-scale` ends up being 4 on your machine. So > > removing the multiplication by `wheel-scale` means that `amt` is 1/4 of > > what it used to be. But `amt` is effectively always divided by > > `WHEEL_DELTA`, which you've also divided by 4 in switching to > > `WHEEL_DELTA_S`. > > > > It seems like those factors of 1/4 would cancel out. Do the numbers > > passed to `do-key` end up being different in some way that I'm missing? > > > > Matthew > > > > At Mon, 12 Apr 2021 04:13:16 -0700 (PDT), Dexter Lagan wrote: > > > I started a new thread as the original topic no longer matched. > > > I installed 8.1.0.2 x64 CS and enabled logging in gen-wheels. Matt was > > > right: wheel-steps-mode is indeed set to 'integer while gen-wheels runs > > in > > > DrRacket's editor. The only two changes required to get smooth/accurate > > > scrolling on touchpad gestures and trackpoint are therefore: > > > > > > In share\pkgs\gui-lib\mred\private\wx\win32\window.rkt's gen-wheels > > private > > > method: > > > > > > (let loop ([amt (* wheel-scale amt)]) > > > to > > > (let loop ([amt amt]) > > > > > > and reduce WHEEL_DELTA by a factor of 4, such as gen-wheels looks like: > > > > > > (define/private (gen-wheels w msg lParam amt down up) > > > (define WHEEL_DELTA_S (/ WHEEL_DELTA 4)) > > > (let loop ([amt amt]) > > > (cond > > > [((abs amt) . < . WHEEL_DELTA_S) > > > (case wheel-steps-mode > > > [(one integer) amt] > > > [(fraction) > > > (unless (zero? amt) > > > (do-key w msg down lParam #f #f void (/ amt (exact->inexact > > > WHEEL_DELTA_S)))) > > > 0.0])] > > > [(negative? amt) > > > (case wheel-steps-mode > > > [(one) > > > (do-key w msg down lParam #f #f void 1.0) > > > (loop (+ amt WHEEL_DELTA_S))] > > > [(integer) > > > (define steps (quotient (- amt) WHEEL_DELTA_S)) > > > (do-key w msg down lParam #f #f void (exact->inexact steps)) > > > (loop (+ amt (* steps WHEEL_DELTA_S)))] > > > [else > > > (do-key w msg down lParam #f #f void (/ (- amt) (exact->inexact > > > WHEEL_DELTA_S))) > > > 0.0])] > > > [else > > > (case wheel-steps-mode > > > [(one) > > > (do-key w msg up lParam #f #f void 1.0) > > > (loop (- amt WHEEL_DELTA_S))] > > > [(integer) > > > (define steps (quotient amt WHEEL_DELTA_S)) > > > (do-key w msg up lParam #f #f void (exact->inexact steps)) > > > (loop (- amt (* steps WHEEL_DELTA_S)))] > > > [else > > > (do-key w msg up lParam #f #f void (/ amt (exact->inexact > > > WHEEL_DELTA_S))) > > > 0.0])]))) > > > > > > Happy Monday, > > > > > > Dex > > > > > > -- > > > You received this message because you are subscribed to the Google > > Groups > > > "Racket Users" group. > > > To unsubscribe from this group and stop receiving emails from it, send > > an email > > > to racket-users...@googlegroups.com. > > > To view this discussion on the web visit > > > > > > https://groups.google.com/d/msgid/racket-users/28e13460-c86d-4967-aa25-5527d672e > > > 711n%40googlegroups.com. > > > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email > to racket-users+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/racket-users/c604a711-b12d-4b82-bb17-819f2ab14 > 2d0n%40googlegroups.com. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. 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