1 files changed, 160 insertions, 0 deletions
diff --git a/src/3rdparty/autotrace/spline.c b/src/3rdparty/autotrace/spline.c
new file mode 100644
index 0000000..3aa0f73
--- /dev/null
+++ b/src/3rdparty/autotrace/spline.c
@@ -0,0 +1,160 @@
+/* spline.c: spline and spline list (represented as arrays) manipulation. */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif /* Def: HAVE_CONFIG_H */
+
+#include "logreport.h"
+#include "types.h"
+#include "spline.h"
+#include "vector.h"
+#include "xstd.h"
+#include <assert.h>
+
+/* Print a spline in human-readable form.  */
+
+void print_spline(spline_type s)
+{
+  assert(SPLINE_DEGREE(s) == LINEARTYPE || SPLINE_DEGREE(s) == CUBICTYPE);
+
+  if (SPLINE_DEGREE(s) == LINEARTYPE)
+    fprintf(stdout, "(%.3f,%.3f)--(%.3f,%.3f).\n", START_POINT(s).x, START_POINT(s).y, END_POINT(s).x, END_POINT(s).y);
+
+  else if (SPLINE_DEGREE(s) == CUBICTYPE)
+    fprintf(stdout, "(%.3f,%.3f)..ctrls(%.3f,%.3f)&(%.3f,%.3f)..(%.3f,%.3f).\n", START_POINT(s).x, START_POINT(s).y, CONTROL1(s).x, CONTROL1(s).y, CONTROL2(s).x, CONTROL2(s).y, END_POINT(s).x, END_POINT(s).y);
+}
+
+/* Evaluate the spline S at a given T value.  This is an implementation
+   of de Casteljau's algorithm.  See Schneider's thesis, p.37.
+   The variable names are taken from there.  */
+
+at_real_coord evaluate_spline(spline_type s, gfloat t)
+{
+  spline_type V[4];             /* We need degree+1 splines, but assert degree <= 3.  */
+  signed i, j;
+  gfloat one_minus_t = (gfloat) 1.0 - t;
+  polynomial_degree degree = SPLINE_DEGREE(s);
+
+  for (i = 0; i <= degree; i++) {
+    V[0].v[i].x = s.v[i].x;
+    V[0].v[i].y = s.v[i].y;
+    V[0].v[i].z = s.v[i].z;
+  }
+
+  for (j = 1; j <= degree; j++)
+    for (i = 0; i <= degree - j; i++) {
+      at_real_coord t1 = Pmult_scalar(V[j - 1].v[i], one_minus_t);
+      at_real_coord t2 = Pmult_scalar(V[j - 1].v[i + 1], t);
+      at_real_coord temp = Padd(t1, t2);
+      V[j].v[i].x = temp.x;
+      V[j].v[i].y = temp.y;
+      V[j].v[i].z = temp.z;
+    }
+
+  return V[degree].v[0];
+}
+
+/* Return a new, empty, spline list.  */
+
+spline_list_type *new_spline_list(void)
+{
+  spline_list_type *answer;
+
+  XMALLOC(answer, sizeof(spline_list_type));
+  *answer = empty_spline_list();
+  return answer;
+}
+
+spline_list_type empty_spline_list(void)
+{
+  spline_list_type answer;
+  SPLINE_LIST_DATA(answer) = NULL;
+  SPLINE_LIST_LENGTH(answer) = 0;
+  return answer;
+}
+
+/* Return a new spline list with SPLINE as the first element.  */
+
+spline_list_type *new_spline_list_with_spline(spline_type spline)
+{
+  spline_list_type *answer;
+
+  answer = new_spline_list();
+  XMALLOC(SPLINE_LIST_DATA(*answer), sizeof(spline_type));
+  SPLINE_LIST_ELT(*answer, 0) = spline;
+  SPLINE_LIST_LENGTH(*answer) = 1;
+
+  return answer;
+}
+
+/* Free the storage in a spline list.  We don't have to free the
+   elements, since they are arrays in automatic storage.  And we don't
+   want to free the list if it was empty.  */
+
+void free_spline_list(spline_list_type spline_list)
+{
+  free(SPLINE_LIST_DATA(spline_list));
+}
+
+/* Append the spline S to the list SPLINE_LIST.  */
+
+void append_spline(spline_list_type * l, spline_type s)
+{
+  assert(l != NULL);
+
+  SPLINE_LIST_LENGTH(*l)++;
+  XREALLOC(SPLINE_LIST_DATA(*l), SPLINE_LIST_LENGTH(*l) * sizeof(spline_type));
+  LAST_SPLINE_LIST_ELT(*l) = s;
+}
+
+/* Tack the elements in the list S2 onto the end of S1.
+   S2 is not changed.  */
+
+void concat_spline_lists(spline_list_type * s1, spline_list_type s2)
+{
+  unsigned this_spline;
+  unsigned new_length;
+
+  assert(s1 != NULL);
+
+  new_length = SPLINE_LIST_LENGTH(*s1) + SPLINE_LIST_LENGTH(s2);
+
+  XREALLOC(SPLINE_LIST_DATA(*s1), new_length * sizeof(spline_type));
+
+  for (this_spline = 0; this_spline < SPLINE_LIST_LENGTH(s2); this_spline++)
+    SPLINE_LIST_ELT(*s1, SPLINE_LIST_LENGTH(*s1)++)
+        = SPLINE_LIST_ELT(s2, this_spline);
+}
+
+/* Return a new, empty, spline list array.  */
+
+spline_list_array_type new_spline_list_array(void)
+{
+  spline_list_array_type answer;
+
+  SPLINE_LIST_ARRAY_DATA(answer) = NULL;
+  SPLINE_LIST_ARRAY_LENGTH(answer) = 0;
+
+  return answer;
+}
+
+/* Free the storage in a spline list array.  We don't
+   want to free the list if it is empty.  */
+void free_spline_list_array(spline_list_array_type * spline_list_array)
+{
+  unsigned this_list;
+
+  for (this_list = 0; this_list < SPLINE_LIST_ARRAY_LENGTH(*spline_list_array); this_list++)
+    free_spline_list(SPLINE_LIST_ARRAY_ELT(*spline_list_array, this_list));
+
+  free(SPLINE_LIST_ARRAY_DATA(*spline_list_array));
+}
+
+/* Append the spline S to the list SPLINE_LIST_ARRAY.  */
+
+void append_spline_list(spline_list_array_type * l, spline_list_type s)
+{
+  SPLINE_LIST_ARRAY_LENGTH(*l)++;
+  XREALLOC(SPLINE_LIST_ARRAY_DATA(*l), SPLINE_LIST_ARRAY_LENGTH(*l) * sizeof(spline_list_type));
+  LAST_SPLINE_LIST_ARRAY_ELT(*l) = s;
+}