1 files changed, 22 insertions, 1 deletions

diff --git a/multimixer.scad b/multimixer.scad
index 88fd6bf..0893457 100644
--- a/multimixer.scad
+++ b/multimixer.scad
@@ -1,79 +1,100 @@
 layer_height=.2; extrusion_width=.5;
 epsilon=.01;
 
 use <pushfittery.scad>;
 include <pushfit_data.scad>;
 
 module multimixer(
  filament_d = 1.75,
  liner_od = 4, liner_id = 2,
  angle = 15,    // to the vertical (output) axis
  inputs = 4,
  minshell = 2*extrusion_width,
  shell = 5*extrusion_width,
  pf = pushfit_embeddest,
  debug = true
 ) {
  fnd = 4*PI; fnr = 2*fnd;
  
  pushfit_d = pf_d(pf);
  pushfit_h = pf_h(pf);
  
  angular_step = 360/inputs;
  inputogon_angle = 180*(inputs-2)/inputs;
  
  sinsin = sin(angle)*sin(angular_step/2);
  function l_to(d) = d*cos(asin(sinsin))/sinsin;
  l_output = liner_od;
  l_input = l_to(pushfit_d/2+minshell);
  l_fork = l_to(liner_id/2);
  l_narrow = l_to(liner_od/2+minshell);
  
  module forinputs() {
   for(zr=[0:angular_step:359]) rotate([0,0,zr]) rotate([0,angle,0]) children();
  }//forinputs module
  module foroutput() {
   rotate([180,0,0]) children();
  }
  
  //translate([pf_d(pf)/2+shell,0,0])
  //translate([0,0,l_output+pushfit_h])
- difference() {
+ module laydown(dia) {
+  r = dia/2;
+  h_bottom = l_output+pushfit_h;
+  /* The top point on the cylinder that will touch the bed */
+  x0 = r*cos(angular_step/2);
+  y0 = r*sin(angular_step/2);
+  z0 = l_input+pushfit_h;
+  /* The same point after rotation by "angle" around Y axis */
+  x1 = z0*sin(angle)+x0*cos(angle);
+  y1 = y0;
+  z1 = z0*cos(angle)-x0*sin(angle);
+  ax1 = atan(y1/x1);
+  /* And its x-coordinate after final "angular_step/2" Z-rotation */
+  ax2 = ax1-angular_step/2;
+  x2 = x1*cos(ax2)/cos(ax1);
+  laydown_angle = atan((x2-r)/(z1+h_bottom));
+  rotate([90-laydown_angle,0,0])
+   translate([0,r,h_bottom])
+    rotate([0,0,angular_step/2-90])
+     children();
+ }
+ laydown(dia=pushfit_d+shell*2) difference() {
   hull() {
    forinputs()
     translate([0,0,l_input+pushfit_h]) mirror([0,0,1])
     cylinder(d=pushfit_d+shell*2,h=epsilon,$fn=pushfit_d*fnd);
    foroutput()
     translate([0,0,l_output+pushfit_h]) {
      cylinder(d=pushfit_d+shell*2,h=epsilon,$fn=pushfit_d*fnd);
     }
   }
   forinputs() {
    translate([0,0,l_input]) pushfit(pf);
    translate([0,0,l_narrow]) {
     cylinder(d=liner_od,h=l_input+1-l_narrow,$fn=liner_od*fnd);
     mirror([0,0,1]) translate([0,0,-epsilon])
     cylinder(d1=(liner_id+liner_od)/2,d2=liner_id,h=liner_id,$fn=liner_od*fnd);
    }
    cylinder(d=liner_id,h=l_input+epsilon,$fn=liner_id*fnd);
   }
   foroutput() {
    translate([0,0,l_output]) pushfit(pf);
    cylinder(d=liner_od,h=l_input+1,$fn=liner_od*fnd);
   }
   hull() {
    forinputs()
     translate([0,0,l_fork]) cylinder(d=liner_id,h=epsilon,$fn=liner_id*fnd);
    foroutput()
     cylinder(d=liner_id,h=epsilon,$fn=liner_id*fnd);
   }
   if(debug) {
    translate([0,0,-20/*TODO:*/])
    rotate_extrude(angle=angular_step)
    square([50,100]/*TODO:*/);
   }
  }
 
 }
 
 multimixer(debug=true);