diff options
Diffstat (limited to 'converter/other/pamtosvg/spline.c')
| -rw-r--r-- | converter/other/pamtosvg/spline.c | 34 |
1 files changed, 24 insertions, 10 deletions
diff --git a/converter/other/pamtosvg/spline.c b/converter/other/pamtosvg/spline.c index 61167ec4..a62ce895 100644 --- a/converter/other/pamtosvg/spline.c +++ b/converter/other/pamtosvg/spline.c @@ -18,23 +18,24 @@ print_spline (FILE *f, spline_type s) if (SPLINE_DEGREE (s) == LINEARTYPE) fprintf (f, "(%.3f,%.3f)--(%.3f,%.3f).\n", - START_POINT (s).x, START_POINT (s).y, + BEG_POINT (s).x, BEG_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); + BEG_POINT (s).x, BEG_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 +Point evaluate_spline (spline_type s, float t) { spline_type V[4]; /* We need degree+1 splines, but assert degree <= 3. */ @@ -52,9 +53,9 @@ evaluate_spline (spline_type s, float t) 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); + Point t1 = point_scaled(V[j - 1].v[i], one_minus_t); + Point t2 = point_scaled(V[j - 1].v[i + 1], t); + Point temp = point_sum(t1, t2); V[j].v[i].x = temp.x; V[j].v[i].y = temp.y; V[j].v[i].z = temp.z; @@ -64,6 +65,7 @@ evaluate_spline (spline_type s, float t) } + /* Return a new, empty, spline list. */ spline_list_type * @@ -76,7 +78,9 @@ new_spline_list (void) return answer; } -spline_list_type + + +spline_list_type empty_spline_list (void) { spline_list_type answer; @@ -85,6 +89,8 @@ empty_spline_list (void) return answer; } + + /* Return a new spline list with SPLINE as the first element. */ spline_list_type * @@ -101,6 +107,7 @@ new_spline_list_with_spline (spline_type spline) } + /* 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. */ @@ -115,6 +122,7 @@ free_spline_list(spline_list_type spline_list) { } + /* Append the spline S to the list SPLINE_LIST. */ void @@ -128,6 +136,7 @@ append_spline (spline_list_type *l, spline_type s) } + /* Tack the elements in the list S2 onto the end of S1. S2 is not changed. */ @@ -149,6 +158,7 @@ concat_spline_lists (spline_list_type *s1, spline_list_type s2) } + /* Return a new, empty, spline list array. */ spline_list_array_type @@ -163,6 +173,7 @@ new_spline_list_array (void) } + /* Free the storage in a spline list array. We don't want to free the list if it is empty. */ void @@ -182,6 +193,7 @@ free_spline_list_array (spline_list_array_type *spline_list_array) } + /* Append the spline S to the list SPLINE_LIST_ARRAY. */ void @@ -193,3 +205,5 @@ append_spline_list (spline_list_array_type *l, spline_list_type s) LAST_SPLINE_LIST_ARRAY_ELT (*l) = s; } + + |