From ca454669d1984c0bb6729b4d9fab9c1730b8d11a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marek=20Ne=C4=8Dada?= <marek@necada.org>
Date: Wed, 22 Aug 2018 19:22:11 +0300
Subject: [PATCH] Dudom doopravdy

Former-commit-id: bc76e84f71750f47f07a3a08bf49044dc9f1ae70
---
 qpms/lattices2d.c | 82 +++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 75 insertions(+), 7 deletions(-)

diff --git a/qpms/lattices2d.c b/qpms/lattices2d.c
index 07c3c68..da2e875 100644
--- a/qpms/lattices2d.c
+++ b/qpms/lattices2d.c
@@ -3,7 +3,7 @@
 
 typedef struct {
   int i, j;
-} intcoord2d;
+} intcoord2_t;
 
 static inline int sqi(int x) { return x*x; }
 
@@ -77,6 +77,15 @@ static inline int trilat_r2_ij(const int i, const int j) {
   return sqi(i) + sqi(j) + i*j;
 }
 
+static inline int trilat_r2_coord(const intcoord2_t c) {
+  return trilat_r2_ij(c.i, c.j);
+}
+
+static int trilat_cmp_intcoord2_by_r2(const void *p1, const void *p2) {
+  // CHECK the sign is right
+  return trilat_r2_coord(*(const intcoord2_t *)p1) - trilat_r2_coord(*(const intcoord2_t *)p2);
+}
+
 // Classify points into sextants (variant [a])
 static int trilat_sextant_ij_a(const int i, const int j) {
   const int w = i + j;
@@ -90,10 +99,18 @@ static int trilat_sextant_ij_a(const int i, const int j) {
   assert(0); // other options should be impossible
 }
 
-
-
 typedef struct {
-  TODO;
+  intcoord2_t *pointlist_base; // allocated memory for the point "buffer"
+  size_t pointlist_capacity; 
+  // beginning and end of the point "buffer"
+  // not 100% sure what type should I use here
+  // (these are both relative to pointlist_base, due to possible realloc's)
+  ptrdiff_t pointlist_beg, pointlist_end; 
+  int maxs; // the highest layer of the spider web generated (-1 by init, 0 is only origin (if applicable))
+  // capacities of the arrays in ps
+  size_t ps_rs_capacity;
+  size_t ps_points_capacity; // this is the "base" array
+  // TODO anything else?
 } triangular_lattice_gen_t_privstuff_t;
 
 triangular_lattice_gen_t * triangular_lattice_gen_init(double a, TriangularLatticeOrientation ori, bool include_origin)
@@ -103,11 +120,62 @@ triangular_lattice_gen_t * triangular_lattice_gen_init(double a, TriangularLatti
   g->includes_origin = include_origin;
   g->ps.nrs = 0;
   g->ps.rs = NULL;
-  g->ps.points_at_r = NULL;
+  g->ps.base = NULL;
+  g->ps.r_offsets = NULL;
   g->priv = malloc(sizeof(triangular_lattice_gen_privstuff_t));
-  TODO;
-
+  g->priv->maxs = -1;
+  g->priv->pointlist_capacity = 0;
+  g->priv->pointlist_base = NULL;
+  g->priv->pointlist_beg = 0;
+  g->priv->pointlist_end = 0;
+  g->priv->ps_rs_capacity = 0;
+  g->priv->ps_points_capacity = 0;
   return g;
 }
 
+void triangular_lattice_gen_free(triangular_lattice_get_t *g) {
+  free(g->ps.rs);
+  free(g->ps.base);
+  free(g->ps.r_offsets);
+  free(g->priv->pointlist_base);
+  free(g->priv);
+  free(g);
+}
+
+const points2d_reordered_t * triangular_lattice_gen_getpoints(const triangular_lattice_generator_t *g) {
+  return &(g->ps);
+}
+
+int triangular_lattice_gen_extend_to_steps(triangular_lattice_generator_t * g, int maxsteps) {
+  if (maxsteps <= g->priv->maxs)  // nothing needed
+    return 0;
+  // TODO FIXME: check for maximum possible maxsteps (not sure what it is)
+  int err;
+  err = trilatgen_ensure_pointlist_capacity(g, maxsteps);
+  if(err) return err;
+  err = trilatgen_ensure_ps_rs_capacity(g, maxsteps);
+  if(err) return err;
+  err = trilatgen_ensure_ps_points_capacity(g, maxsteps);
+  if(err) return err;
+  
+  if(g->includes_origin && g->priv->maxs < 0) // Add origin if not there yet
+    trilatgen_append_ij(g, 0, 0);
+  
+  for (int s = g->priv->maxs + 1; s <= maxsteps; ++s) {
+    int i, j; 
+    // now go along the spider web layer as indicated in the lenghthy comment above
+    for (i = s, j = 0; i > 0; --i; ++j) trilatgen_append_ij(g,i,j);
+    for (i = 0, j = s; i + j > 0; --i) trilatgen_append_ij(g,i,j);
+    for (i = -s, j = s; j > 0; --j) trilatgen_append_ij(g,i,j);
+    for (i = -s, j = 0; i < 0; ++i, --j) trilatgen_append_ij(g,i,j);
+    for (i = 0, j = -s; i + j < 0; ++i) trilatgen_append_ij(g,i,j);
+    for (i = s, j = -s; j < 0; ++j) trilatgen_append_ij(g,i,j);
+  }
+
+  trilatgen_sort_pointlist(g);
+  
+  // TODO doma a ted je potřeba vytahat potřebný počet bodů z fronty a naflákat je do ps.
+
+
+