fairphone-case: prop: fix senses of triangle adjustments

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

diff --git a/fairphone-case.scad b/fairphone-case.scad
index 5da56cfc67249d818ce2208a3292dcd279960b7f..09c40e8365ddd9a22c31a17ce083f4886a957adc 100644 (file)
--- a/fairphone-case.scad
+++ b/fairphone-case.scad
@@ -627,10 +627,10 @@ function prop_x(gamma) = hp_k / (2 * sin(gamma/2)) - hppT[0];
 module PropProfileAssignments(gamma){
   // https://en.wikipedia.org/wiki/Solution_of_triangles#Two_sides_and_the_included_angle_given_(SAS)
   x = prop_x(gamma);
-  p = phone_height - prlp10[0] - hppB[0];
+  p = phone_height + prlp10[0] - hppB[0];
   b = p + x;
 
-  q = phone_height - hppT[0]; // $prpp7[0] is 0 by definition
+  q = phone_height - hppT[0] - prcp1[0]; // $prpp7[0] is 0 by definition
   a = q + x;
   c = sqrt(a*a + b*b - 2*a*b*cos(gamma));
   $prp_alpha = acos( (b*b + c*c - a*a) / (2*b*c) );