iphone - how to shift the slider image knot outside -

-

i have difficulties understanding math behind on how calculate circumference of knots center of circle. hope guys can give me pointer.

the current calculation set knot img in middle of pie, shift nearer outer circle in img 2

thank viewing , commenting, comments appreciated.

enter image description here

how wan be. enter image description here

/** draw white knob on circle **/ -(void) drawthehandle:(cgcontextref)ctx{      cgcontextsavegstate(ctx);     nslog(@"handlecentera.x %f",handlecentera.x);     nslog(@" handlecentera.y %f", handlecentera.y);     [[uicolor colorwithwhite:1.0 alpha:1.0]set];     uiimage *myimage = [uiimage imagenamed:@"clock-marker.png"];      //this give me result of image 1     [myimage drawinrect:cgrectmake(handlecentera.x-35, handlecentera.y-40, tb_button_width, tb_button_width)];      //this give me result of image 2     [myimage drawinrect:cgrectmake(handlecentera.x-35, handlecentera.y-40, tb_button_width, tb_button_width)];      cgcontextrestoregstate(ctx); }  #pragma mark - math -  /** move handle **/ -(void)movehandle:(cgpoint)lastpoint{      //get center     cgpoint centerpoint = cgpointmake(self.frame.size.width/2, self.frame.size.height/2);      //calculate direction center point , arbitrary position.     //float currentangle = anglefromnorth(centerpoint, lastpoint, no);     //int angleint = floor(currentangle);       //calculate direction center point arbitrary position.     float currentangle = anglefromnorth(centerpoint, lastpoint, no);     int angleint = 360 - floor(currentangle);      if (sliderlock == sliderlockedstart) {         self.startangle = angleint;     }     //redraw     [self setneedsdisplay]; }  - (cgpoint)centerpointfromangel:(int)angleint {     cgpoint point = [self pointfromangle:angleint];     point.x += tb_button_width/2;     point.y += tb_button_width/2;     return point; }  - (cgfloat)distancebetween:(cgpoint)p1 and:(cgpoint)p2 {     cgfloat xdist = (p2.x - p1.x);     cgfloat ydist = (p2.y - p1.y);     return sqrt((xdist * xdist) + (ydist * ydist)); }  /** given angle, point position on circumference **/ -(cgpoint)pointfromangle:(int)angleint{      //circle center     cgpoint centerpoint = cgpointmake(self.frame.size.width/2 - (tb_button_width/2), self.frame.size.height/2 - (tb_button_width/2));      //the point position on circumference     cgpoint result;     result.y = round(centerpoint.y + radius * sin(torad(-angleint))) ;     result.x = round(centerpoint.x + radius * cos(torad(-angleint)));         return result; }  //sourcecode apple example clockcontrol  //calculate direction in degrees center point arbitrary position. static inline float anglefromnorth(cgpoint p1, cgpoint p2, bool flipped) {     cgpoint v = cgpointmake(p2.x-p1.x,p2.y-p1.y);     float vmag = sqrt(sqr(v.x) + sqr(v.y)), result = 0;     v.x /= vmag;     v.y /= vmag;     double radians = atan2(v.y,v.x);     result = todeg(radians);     return (result >=0  ? result : result + 360.0); }

finally solved it.

/** given angle, point position on circumference **/

-(cgpoint)pointfromangle:(int)angleint{      //circle center//tb_button_width     cgpoint centerpoint = cgpointmake(self.frame.size.width/2 - (tb_button_width/2), self.frame.size.height/2 - (tb_button_width/2));      //the point position on circumference radius     cgpoint result;     result.y = round(centerpoint.y + 120 * sin(torad(-angleint))) ;     result.x = round(centerpoint.x + 120 * cos(torad(-angleint)));          nslog(@"centerpoint %@",nsstringfromcgpoint(centerpoint));         nslog(@"result %@",nsstringfromcgpoint(result));     return result; }

Popular posts from this blog

How to calculate SNR of signals in MATLAB? -

-
i've encountered simple, yet fundamental problem on calculating snr: there several signals : s1 = original , pure clean signal without noise. n1 = white gaussian noise going added s1. s2 = s1 + n1 (the noisy signal before performing noise-reduction algorithm) s3 = noise-reduced signal (after performing noise reduction algorithm) n2 = s3 - s1 (the amount of noise after performing noise-reduction algorithm) now want compare snr before , after performing noise-reduction algorithm. which signals should consider snr_before!? s1/n1 or s2/n1 ? which signals should consider snr_after!? s3/n1 or s3/n2 ? which commands or functions should use in matlab in order compute snr_before , snr_after? thanks billion putting time on helping me. what know calculating snr before : snrbeforenoise = mean( signal .^ 2 ) / mean( noise .^ 2 ); and snr after : residual_noise = signal - noise_reduced_signal; snr_after = mean( signal .^ 2 ) / mean( residual_noise .^ 2
Read more

c# - Attempting to upload to FTP: System.Net.WebException: System error -

-
i have api takes in xml , uploads files based on information in xml. uploads on schedule (also xml), , have tested surrounding , know works. i getting error 40% of time on first file attempt upload in each time cycle (time cycle = 45 minutes files, 30 minutes others). here code upload: try { loggerftp.log("uploading file: " + filename, false); // create request. ftpwebrequest request = (ftpwebrequest)webrequest.create(appsettingsftp.ftpurl + @"/" + filename); request.method = webrequestmethods.ftp.uploadfile; request.timeout = 6000000; //set 100 minutes //request.timeout = -1; //set infinite // add login credentials. request.credentials = new networkcredential(appsettingsftp.ftplogin, appsettingsftp.ftppassword); // grab file contents. streamreader sourcestream = new streamreader(appsettingsftp.uploadfiledirectory + filename); byte[] filecontents = encoding.utf8.getbytes(sourcestream.readtoend()); sourcest
Read more

ios - UISlider customization: how to properly add shadow to custom knob image -

-
Image
i need place custom knob image shadow uislider. far have image of 38x38, of there region defines shadow of knob. now while using image, when slide knob extreme ends actual knob not able cover end points, hence end points visible under transparent region of knob image this code using customize uislider uiimage *slidebtimg = [uiimage imagenamed:sliderknobimg]; [self.ratingslider setthumbimage:slidebtimg forstate:uicontrolstatenormal]; [self.ratingslider setthumbimage:slidebtimg forstate:uicontrolstatehighlighted]; how can implement custom knob shadow beneath it, covering end points?? look inside uislider.h , there methods let customize slider knob , track needed. (ios 2.0 , above) // lets subclass lay out track , thumb needed - (cgrect)minimumvalueimagerectforbounds:(cgrect)bounds; - (cgrect)maximumvalueimagerectforbounds:(cgrect)bounds; - (cgrect)trackrectforbounds:(cgrect)bounds; - (cgrect)thumbrectforbounds:(cgrect)bounds trackrect:(cgrect)rect value:
Read more