How To Draw A Water Lily Easy

Using LuaTeX, it is easy to generate some more generic results.

          \documentclass{article} \usepackage{tikz} \usepackage{luacode}  \begin{document}  \tikzset{   arcstyle/.style={     thick   } }  \begin{luacode*} one_degree = math.pi / 180  function get_inscribed_point(radius, n_poly, index, rotation)   local ang = (360.0 / n_poly * index + rotation) * one_degree   local x = radius * math.cos(ang)   local y = radius * math.sin(ang)   return {x,y} end   function get_arc_info(p1, p2, p3)   local xa, ya = table.unpack(p1)   local xb, yb = table.unpack(p2)   local xc, yc = table.unpack(p3)      local coef1 = xb*xb - xc*xc + yb*yb - yc*yc   local coef2 = xa*xa - xb*xb + ya*ya - yb*yb   local coef3 = 2.0 * ((xa-xb)*(yb-yc)-(xb-xc)*(ya-yb))      -- calculate center   local center_x = (-(ya-yb)*coef1+(yb-yc)*coef2)/coef3   local center_y = ((xa-xb)*coef1-(xb-xc)*coef2)/coef3      -- calculate radius   local radius = math.sqrt(math.pow(xa-center_x, 2)+math.pow(ya-center_y, 2))      -- calculate arc angle range   local arc_ang1 = math.asin((0.5*math.sqrt(math.pow(xb-xa,2)+math.pow(yb-ya,2))/radius))   local arc_ang2 = math.asin((0.5*math.sqrt(math.pow(xc-xb,2)+math.pow(yc-yb,2))/radius))   local arc_angle = (arc_ang1 + arc_ang2) * 2.0      -- find out if (xc,yc) or (xa,ya) has the smallest angle   -- make sure xc has the smallest angle (if not, swap two points)   local ang_a = math.atan2(ya-center_y,xa-center_x)   local ang_c = math.atan2(yc-center_y,xc-center_x)   if ang_a < ang_c then     ang_a = ang_a + 2 * math.pi   end      -- determine start angle   local start_angle =ang_c   local end_angle = ang_a      -- return results   return {     ["center_x"] = center_x,     ["center_y"] = center_y,     ["radius"] = radius,     ["start_angle"] = start_angle / one_degree,     ["end_angle"] = end_angle / one_degree,     ["arc_start_x"] = xc,     ["arc_start_y"] = yc   } end  function draw_arc(p1, p2, p3)     local arc = get_arc_info(p1, p2, p3)            tex.print(string.format([[\draw[arcstyle] (%f cm, %f cm) arc (%f:%f:%f cm);]],       arc["arc_start_x"],       arc["arc_start_y"],       arc["start_angle"],       arc["end_angle"],       arc["radius"])) end  function draw_lily(radius, n_poly, offset, rotation)   for i=1,n_poly do     local ind1 = i - 1     local ind2 = (i+offset - 1)%n_poly     local p1 = get_inscribed_point(radius, n_poly, ind1, rotation)     local p2 = {0.0,0.0}     local p3 = get_inscribed_point(radius, n_poly, ind2, rotation)     draw_arc(p1, p2, p3)   end end  \end{luacode*}   \begin{tikzpicture} \draw (0,0) circle (2cm); \directlua{   draw_lily(2.0, 6, 2, 0.0) } \end{tikzpicture} \begin{tikzpicture} \draw (0,0) circle (2cm); \directlua{   draw_lily(2.0, 6, 2, 15.0) } \end{tikzpicture} \begin{tikzpicture} \draw (0,0) circle (2cm); \directlua{   draw_lily(2.0, 8, 2, 15.0) } \end{tikzpicture} \begin{tikzpicture} \draw (0,0) circle (2cm); \directlua{   draw_lily(2.0, 12, 2, 15.0) } \end{tikzpicture} \begin{tikzpicture} \draw (0,0) circle (2cm); \directlua{   draw_lily(2.0, 12, 3, 15.0) } \end{tikzpicture} \begin{tikzpicture} \draw (0,0) circle (2cm); \directlua{   draw_lily(2.0, 12, 4, 15.0) } \end{tikzpicture} \begin{tikzpicture} \draw (0,0) circle (2cm); \directlua{   draw_lily(2.0, 36, 2, 15.0) } \end{tikzpicture}  \end{document}                  

How To Draw A Water Lily Easy

Source: https://tex.stackexchange.com/questions/573574/how-can-i-draw-a-water-lily-in-latex

Posted by: compoorwastincer.blogspot.com

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