File:Shearstrain Solid Mechanics.png

prologues := 2; % input metaobj.mp; extra_endfig := "currentpicture := currentpicture shifted -llcorner currentpicture;"; verbatimtex %&latex \documentclass{article} \begin{document} etex beginfig(1); numeric u; u := .4cm; drawarrow origin -- 7u * right; drawarrow origin -- 7u * up; path pp; pp := origin -- 4u * right -- 4u * right + 4u * dir (75) -- 4u * dir (75) -- cycle; draw pp; path qq; ahangle := 30; qq := halfcircle scaled 10u; qq := qq cutbefore ((origin -- 7u * dir (75)) intersectionpoint qq); qq := qq cutafter ((origin -- 10u * up) intersectionpoint qq); label.top (btex $\gamma$ etex, origin) shifted (center qq); drawdblarrow qq; draw 4.2u * dir (75) -- 7u * dir (75) withpen pencircle scaled .25; vardef arrowhead expr p = save A,u,a,b; pair A,u; path a,b; A := point length(p) of p;   u := unitvector(direction length(p) of p); a := A{-u}..(A - ahlength*u rotated -30); b := A{-u}..(A - ahlength*u); (a & reverse(a) & b & reverse(b))--cycle enddef; pair p, q; p := (point 1 of pp) + .5u * dir (-135); q :=  (point 0 of pp) + .5u * dir (-45); drawarrow p -- q; label.bot (btex $\tau$ etex, 1/2[p,q]); p := (point 3 of pp) + .5u * dir (45); q :=  (point 2 of pp) + .5u * dir (135); drawarrow p -- q; label.top (btex $\tau$ etex, 1/2[p,q]); vardef arrowhead expr p = save A,u,a,b; pair A,u; path a,b; A := point length(p) of p;   u := unitvector(direction length(p) of p); a := A{-u}..(A - ahlength*u rotated 30); b := A{-u}..(A - ahlength*u); (a & reverse(a) & b & reverse(b))--cycle enddef; p := (point 1 of pp) + .5u * dir (30); q :=  (point 2 of pp) + .5u * dir (-60); drawarrow p -- q; label.rt (btex $\tau$ etex, 1/2[p,q]); p := (point 3 of pp) - .5u * dir (30); q := (point 0 of pp) - .5u * dir (-60); drawarrow p -- q; label.lft (btex $\tau$ etex, 1/2[p,q]); currentpicture := currentpicture scaled 2; endfig; end;