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watertight polygons

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I fixd the polygons!  I just had to remove the equal-to-endpoint rule and add a more specific exception for λ=-π.
This commit is contained in:
Justin Kunimune 2023-06-19 20:28:33 -07:00
parent 4675409725
commit ca0d6de292
1 changed files with 27 additions and 27 deletions
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54
src/maps/Elastik.java
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@ -443,29 +443,29 @@ public class Elastik {
for (int i = 1; i < ф_vertices.length; i ++) {
if (abs(λ_vertices[i] - λ_vertices[i - 1]) > PI)
continue; // skip edges that are wrapping around the backside
// if our north-south line crosses it
if (λ_vertices[i - 1] != λ_vertices[i]) {
if ((λ_vertices[i - 1] < λ) != (λ_vertices[i] < λ) ||
λ_vertices[i - 1] == λ || λ_vertices[i] == λ) {
// calculate *where* it crosses
double ф_intersect;
if (ф_vertices[i - 1] != ф_vertices[i]) {
double Δλ0 = λ - λ_vertices[i - 1];
double Δλ1 = λ_vertices[i] - λ;
ф_intersect = (ф_vertices[i - 1]*Δλ1 + ф_vertices[i]*Δλ0)/(Δλ0 + Δλ1);
}
else {
ф_intersect = ф_vertices[i]; // be mindful of efficiency and avoiding roundoff
}
double Δф = abs(ф_intersect - ф);
if (Δф == 0)
return true; // if it's on the line, count it as in
// otherwise, count this crossing
if ((ф_intersect < ф) == (λ_vertices[i - 1] < λ_vertices[i]))
crossings += 1;
else
crossings -= 1;
// see if our north-south line crosses it
boolean crosses = (λ_vertices[i - 1] < λ) != (λ_vertices[i] < λ) ||
(λ == -PI && min(λ_vertices[i - 1], λ_vertices[i]) == -PI);
if (crosses) {
// calculate *where* it crosses
double ф_intersect;
if (ф_vertices[i - 1] != ф_vertices[i]) {
double Δλ0 = λ - λ_vertices[i - 1];
double Δλ1 = λ_vertices[i] - λ;
ф_intersect = (ф_vertices[i - 1]*Δλ1 + ф_vertices[i]*Δλ0)/(Δλ0 + Δλ1);
}
else {
ф_intersect = ф_vertices[i]; // be mindful of efficiency and avoiding roundoff
}
double Δф = abs(ф_intersect - ф);
if (Δф == 0)
return true; // if it's on the line, count it as in
// otherwise, count this crossing
if ((ф_intersect < ф) == (λ_vertices[i - 1] < λ_vertices[i]))
crossings += 1;
else
crossings -= 1;
}
}
return crossings > 0;
@ -488,7 +488,7 @@ public class Elastik {
public SplineSurface(double[][] values) {
this.values = values;
// set the gradients at the nodes
// set the gradients at the nodes to finite-difference estimates
final int m = values.length;
final int n = values[0].length;
this.gradients_dф = new double[m][n];
@ -608,13 +608,13 @@ public class Elastik {
SplineSurface[][] surfaces, int i_A, int j_A, int k_A, int i_B, int j_B, int k_B) {
for (int l = 0; l < 2; l ++) {
double mean_gradient_dф = (
surfaces[i_A][l].gradients_dф[j_A][k_A] +
surfaces[i_B][l].gradients_dф[j_B][k_B])/2;
surfaces[i_A][l].gradients_dф[j_A][k_A] +
surfaces[i_B][l].gradients_dф[j_B][k_B])/2;
surfaces[i_A][l].gradients_dф[j_A][k_A] = mean_gradient_dф;
surfaces[i_B][l].gradients_dф[j_B][k_B] = mean_gradient_dф;
double mean_gradient_dλ = (
surfaces[i_A][l].gradients_dλ[j_A][k_A] +
surfaces[i_B][l].gradients_dλ[j_B][k_B])/2;
surfaces[i_A][l].gradients_dλ[j_A][k_A] +
surfaces[i_B][l].gradients_dλ[j_B][k_B])/2;
surfaces[i_A][l].gradients_dλ[j_A][k_A] = mean_gradient_dλ;
surfaces[i_B][l].gradients_dλ[j_B][k_B] = mean_gradient_dλ;
}