animation - Plotting a quadratic equation in Delphi/Lazarus -

-

i trying animate object's position using quadratic equation rapid-start-slow-stop kind of movement.

this available in delphi xe6 using delphi xe2 , lazarus , have created own animation handling system works great actually.

i have linear formula , half-sinus formula, want quadratic formula.

the half-sinus formula move object rapidly @ start , slows down, want more exaggerated curve, rapid @ start , slows down lot , halts.

unfotunately have no code available since code looking for.

i have used our dear friend mr google, no luck finding information can comprehend.

basically needed formula gives floating point number rangin 0 1.

i take delta of position of object needs moved , multiply formula needed.

in animation system have 2 values regarding animation process:

var currentpos, resolution: single;

the value "currentpos" represents position of formula. instance sinus can apply "currentpos" angle, or x axis of plot, , "resolution" max angle (360 degrees) or whole plot view in x axis.

the current formula have found far quadratic equation following:

formula := (-b+(sqr(power10(b, 2)-4*(a*c))))/(2*a);

where in formula put in value of "currentpos"?

or real question, have gotten whole mathematical process wrong?

you want equation in unknown x is:

  1. quadratic in x.
  2. has value of 0 when x = 0.
  3. has value of 1 when x = 1.
  4. varies rapidly when x close 0 , not vary rapidly when x close 1.

your quadratic therefore of form: 1 - (1-x)2.

this has derivative 2 when x = 0 , 0 when x = 1.

you'll need translate input variable in range 0 1. once done feed above formula x.

if want use different exponents can replace exponent. instance cubic version be: 1 - (1-x)3.

in code might write this:

function outpoly(x: real, exponent: integer): real; begin   result := 1 - intpower(1-x, exponent); end;

Comments

Post a Comment

Popular posts from this blog

python - mat is not a numerical tuple : openCV error -

-
i have write down code showing error ma not getting it: please help: showing mat not numerical tuple: import cv import cv2 capture = cv2.videocapture("j.3gp") while(1): _, frame1 = capture.read() grayimage1 = cv2.cvtcolor(frame1, cv2.color_bgr2gray) _, frame2 = capture.read() grayimage2 = cv2.cvtcolor(frame2, cv2.color_bgr2gray) differenceimage = cv2.absdiff(grayimage1,grayimage2) thresholdimage = cv2.threshold(differenceimage,25,255,cv2.thresh_binary) cv2.imshow("difference image", differenceimage) cv2.imshow("threshold image", thresholdimage) cv2.imshow("image", frame1) k = cv2.waitkey(30) & 0xff error arising : ----------------------------------------------------------------------------------------- traceback (most recent call last): file "desk.py", line 15, in <module> cv2.imshow("threshold image", thresholdimage) typeerror: mat not numerical tuple ...
Read more

c# - MSAA finds controls UI Automation doesn't -

-
i'm working on automating windows application. i'm using teststack white framework. i've hit problem. program has 'window' object cannot see inside of. white shows no controls inside of it. inspect.exe shows no controls inside of either when running in ui automation mode. if switch inspect msaa see controls inside fine. there anyway me use msaa c# handle on these controls? if can identify msaa functions need, can use p/invoke call them c#. here's example article doing msaa: http://www.codeproject.com/articles/38906/ui-automation-using-microsoft-active-accessibility also, pinvoke.net can used identify iaccessible (msaa) functions: http://www.pinvoke.net/search.aspx?search=iaccessible&namespace=[all] here's answer along lines: msaa com-based? finally, alternative p/invoke, might able use tlbimp.exe create wrapper assembly oleacc.dll, , access msaa functions through it. i'm not sure if works msaa, it's worth try. as e...
Read more

wordpress - .htaccess: RewriteRule: bad flag delimiters -

-
pulling hair out on one. have following .htaccess file custom redirects in addition wordpress's default settings. when tested on local wamp server worked fine after moving production i'm not getting rewriterule: bad flag delimiters error in server log , after while site goes down internal server error any appreciated. in advance! <ifmodule mod_rewrite.c> rewriteengine on rewritebase / rewriterule ^rockford_weddings___welcome\.html$ /wedding/ [r=301,l] rewriterule ^blog/?$ /journal/ [r=301,l] rewriterule ^blog/(.*)$ /$1 [r=301,l] rewriterule ^portraitinvestment/?$ /portraitinvestment\.pdf [r=301,l] rewriterule ^weddinginvestment/?$ /weddinginvestment\.pdf [r=301,l] rewriterule ^holidaycards2014/?$ /holidaycards2014\.pdf [r=301,l] </ifmodule> # begin wordpress <ifmodule mod_rewrite.c> rewriteengine on rewritebase / rewriterule ^index\.php$ - [l] rewritecond %{request_filename} !-f rewritecond %{request_filename} !-d rewriterule . /index.php [l] </...
Read more