James, "Magnifique*!
Pierre Le 13 nov. 2011 à 07:01, James Hurley a écrit : > Hugh, > > Would this help? The script below will draw a polygon that looks like an > ellipse with a start and stop angle. > > The trouble with the start angle and the arcangle in RR is that they are not > polar angles but are related in a complex way: > > arcAngle = arctangent( b/a * tangent(polarangle) > > (Don't ask.) > > And then use a mousewithin handler for the "oval" grc--actually a polygon > > > local a,b > > on mouseUp > put 10 into tStartAngle -- Or whatever > put 250 into tEndAngle -- Or whatever > put 200 into a --Semi major axis > put 100 into b -- Semi minor axis > put 300 into x0 -- The origin > put 250 into y0 -- The origin > put x0,y0 & cr into tPoints > --Construct the points for the ellipse > repeat with i = tStartANgle to tEndANgle > put r(i) into tR > put round ( x0 + r(i) * cos(i*pi/180)), round(y0+r(i) * sin(i*pi/180)) > into temp > put temp & cr after tPoints > end repeat > > put x0,y0 after tPoints > --Construct the graphic > if there is no grc "oval" then create grc "oval" > set the style of grc "oval" to "polygon" > set the opaque of grc "oval" to true > set the points of grc "oval" to tPoints > end mouseUp > > > function r tA --Radial distance to the ellipse as afunction of the angle > put (cos(tA*pi/180))^2 / (a*a) + (sin(tA*pi/180))^2 / (b*b) into temp > return 1/sqrt(temp) > end r > >> Has anyone worked out how to test if the mouseLoc is within the filled area >> of an oval graphic (defined by startAngle and arcAngle)? I was thinking >> polar coordinates, but this assumes a circle and a fixed radius which is not >> necessarily the case. A btter math brain than mine is needed! >> >> Hugh Senior >> FLCo > > _______________________________________________ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your subscription > preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode -- Pierre Sahores mobile : 06 03 95 77 70 www.sahores-conseil.com _______________________________________________ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
