3D Spinning Glass

ImGui_Party_3D_001.inl

#define V ImVec2
#define F float
void R(F&x,F&y,F r){F s=sin(r),c=cos(r),t=c*x-s*y;y=s*x+c*y;x=t;}
F c,e,f,g,l,x,y,z;
F L(F a){l*=l>0;return sqrt(1-exp(-a*(l+.1)-l*l*l));}
void T(F u){R(x,z,c/3+6.28*u);R(x,y,c);R(y,z,c/5);}
void FX(ImDrawList*d,V a,V b,V S,ImVec4,F t){
int i,j,k,n=0,u,v,K=7,J=16;
char P[]="GZHXITGPBMBCGA",*X=P;
struct Q{F d,l;V o[4];}q[99];
V m=(a+b)/2;
for(k=K;--k;){X+=2;for(j=J;j--;){
Q&o=q[n++];
o.d=0;
for(i=4;i--;){
u=j+(i%3>0);v=-(i/2)*2;
x=X[v]-65;y=77-X[v+1];z=0;
c=t;T((F)u/J);
e=x;f=y;
o.d+=z=S.y/(g=z+40);
o.o[i]=m+V(x,y)*z;
}
x=X[1]-X[-1];y=*X-X[-2];z=0;
l=sqrt(x*x+y*y);
T((j+.5)/J);
o.l=((x*e+y*f+z*g)>0?1:-1)*y/l;
}}
for(i=99;i--;){b.y=a.y;a.y=m.y+9e2/(i+1);d->AddRectFilled(a,b,i>97?0xffffd050:0xff608000+(i/9&1)*64+i*65793);}
for(;c=9e9,j=-1;){
for(i=n;i--;){z=q[i].d;if(z>0&z<c){c=z;j=i;}}
if(j<0)break;
Q&o=q[j];o.d=-1;l=o.l;
d->AddConvexPolyFilled(o.o,4,ImColor(L(.1),L(.3),L(1),.8));
d->AddPolyline(o.o,4,~0<<24,1,1);
}}