1 files changed, 193 insertions, 0 deletions
diff --git a/converter/other/pamtosvg/spline.c b/converter/other/pamtosvg/spline.c
new file mode 100644
index 00000000..5bdf0c0e
--- /dev/null
+++ b/converter/other/pamtosvg/spline.c
@@ -0,0 +1,193 @@
+/* spline.c: spline and spline list (represented as arrays) manipulation. */
+
+#include <assert.h>
+
+#include "mallocvar.h"
+
+#include "message.h"
+#include "point.h"
+#include "spline.h"
+#include "vector.h"
+
+/* Print a spline in human-readable form.  */
+
+void
+print_spline (FILE *f, spline_type s)
+{
+  assert(SPLINE_DEGREE (s) == LINEARTYPE || SPLINE_DEGREE (s) == CUBICTYPE);
+
+  if (SPLINE_DEGREE (s) == LINEARTYPE)
+    fprintf (f, "(%.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 (f, "(%.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.  */
+
+float_coord
+evaluate_spline (spline_type s, float t)
+{
+  spline_type V[4];    /* We need degree+1 splines, but assert degree <= 3.  */
+  signed i, j;
+  float one_minus_t = (float) 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++)
+      {
+        float_coord t1 = Pmult_scalar (V[j - 1].v[i], one_minus_t);
+        float_coord t2 = Pmult_scalar (V[j - 1].v[i + 1], t);
+        float_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;
+
+  MALLOCVAR(answer);
+  *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();
+  MALLOCVAR(SPLINE_LIST_DATA(*answer));
+  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)
+{
+  if (SPLINE_LIST_DATA (spline_list) != NULL)
+    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)++;
+  REALLOCARRAY(SPLINE_LIST_DATA(*l), SPLINE_LIST_LENGTH(*l));
+  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);
+
+  REALLOCARRAY_NOFAIL(SPLINE_LIST_DATA(*s1), new_length);
+
+  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));
+
+  if (SPLINE_LIST_ARRAY_DATA (*spline_list_array) != NULL)
+    free (SPLINE_LIST_ARRAY_DATA (*spline_list_array));
+
+  flush_log_output ();
+}
+
+
+/* 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)++;
+  REALLOCARRAY_NOFAIL(SPLINE_LIST_ARRAY_DATA(*l),
+                      SPLINE_LIST_ARRAY_LENGTH(*l));
+  LAST_SPLINE_LIST_ARRAY_ELT (*l) = s;
+}
+