I'd also be in favor of this change to squared-off miter joints. I've noticed the odd endcap behavior in Pygame a long time ago, and it's one reason that I never used the line drawing function for lines with large widths.
-Al On Sat, Apr 28, 2018 at 1:35 PM, Ian Mallett <i...@geometrian.com> wrote: > By the way, a solution doesn't even need to use any trigonometry, because > a squared-off miter joint is by-definition orthogonal to the line. Here's > some proof-of-concept code: > > def rndint(x): return int(round(x)) > def cappedline(surface, color, p0,p1, width=1, rounded=True): > radius = width * 0.5 > delta = ( p1[0]-p0[0], p1[1]-p0[1] ) > orthog = [ delta[1], -delta[0] ] > scale = radius / (orthog[0]*orthog[0] + orthog[1]*orthog[1])**0.5 > orthog[0]*=scale; orthog[1]*=scale > points = [ > ( p0[0]-orthog[0], p0[1]-orthog[1] ), > ( p0[0]+orthog[0], p0[1]+orthog[1] ), > ( p1[0]+orthog[0], p1[1]+orthog[1] ), > ( p1[0]-orthog[0], p1[1]-orthog[1] ) > ] > pygame.draw.polygon(surface, color, points) > if rounded: > #Could have added these to the polygon points instead, but then > we'd have had to choose a subdivision accuracy. > pygame.draw.circle(surface, color, (rndint(p0[0]),rndint(p0[1])), > rndint(radius)) > pygame.draw.circle(surface, color, (rndint(p1[0]),rndint(p1[1])), > rndint(radius)) > pygame.draw.cappedline = cappedline > > Note that this also supports rounded corners by drawing circles on the > ends, although this is rather limited by the (poor) accuracy of the circle > drawing routine, and doesn't look fabulous at small widths. > > Ian >
