Create Subversion repository

git-svn-id: http://svn.code.sf.net/p/netpbm/code/trunk@1 9d0c8265-081b-0410-96cb-a4ca84ce46f8

1 files changed, 254 insertions, 0 deletions

diff --git a/converter/other/pamtosvg/vector.c b/converter/other/pamtosvg/vector.c
new file mode 100644
index 00000000..559163fc
--- /dev/null
+++ b/converter/other/pamtosvg/vector.c
@@ -0,0 +1,254 @@
+/* vector.c: vector/point operations. */
+
+#include <math.h>
+#include <errno.h>
+#include <assert.h>
+#include <string.h>
+
+#include "pm_c_util.h"
+
+#include "vector.h"
+#include "message.h"
+#include "epsilon-equal.h"
+
+static float acos_d (float, at_exception_type * excep);
+
+
+/* Given the point COORD, return the corresponding vector.  */
+
+vector_type
+make_vector (const float_coord c)
+{
+  vector_type v;
+
+  v.dx = c.x;
+  v.dy = c.y;
+  v.dz = c.z;
+
+  return v;
+}
+
+
+/* And the converse: given a vector, return the corresponding point.  */
+
+float_coord
+vector_to_point (const vector_type v)
+{
+  float_coord coord;
+
+  coord.x = v.dx;
+  coord.y = v.dy;
+
+  return coord;
+}
+
+
+float
+magnitude (const vector_type v)
+{
+  return (float) sqrt (v.dx * v.dx + v.dy * v.dy + v.dz * v.dz);
+}
+
+
+vector_type
+normalize (const vector_type v)
+{
+  vector_type new_v;
+  float m = magnitude (v);
+
+  /* assert (m > 0.0); */
+
+  if (m > 0.0)
+  {
+    new_v.dx = v.dx / m;
+    new_v.dy = v.dy / m;
+    new_v.dz = v.dz / m;
+  }
+  else
+  {
+	new_v.dx = v.dx;
+    new_v.dy = v.dy;
+    new_v.dz = v.dz;
+  }
+
+  return new_v;
+}
+
+
+vector_type
+Vadd (const vector_type v1, const vector_type v2)
+{
+  vector_type new_v;
+
+  new_v.dx = v1.dx + v2.dx;
+  new_v.dy = v1.dy + v2.dy;
+  new_v.dz = v1.dz + v2.dz;
+
+  return new_v;
+}
+
+
+float
+Vdot (const vector_type v1, const vector_type v2)
+{
+  return v1.dx * v2.dx + v1.dy * v2.dy + v1.dz * v2.dz;
+}
+
+
+vector_type
+Vmult_scalar (const vector_type v, const float r)
+{
+  vector_type new_v;
+
+  new_v.dx = v.dx * r;
+  new_v.dy = v.dy * r;
+  new_v.dz = v.dz * r;
+
+  return new_v;
+}
+
+
+/* Given the IN_VECTOR and OUT_VECTOR, return the angle between them in
+   degrees, in the range zero to 180.  */
+
+float
+Vangle (const vector_type in_vector, 
+	const vector_type out_vector,
+	at_exception_type * exp)
+{
+  vector_type v1 = normalize (in_vector);
+  vector_type v2 = normalize (out_vector);
+
+  return acos_d (Vdot (v2, v1), exp);
+}
+
+
+float_coord
+Vadd_point (const float_coord c, const vector_type v)
+{
+  float_coord new_c;
+
+  new_c.x = c.x + v.dx;
+  new_c.y = c.y + v.dy;
+  new_c.z = c.z + v.dz;
+  return new_c;
+}
+
+
+float_coord
+Vsubtract_point (const float_coord c, const vector_type v)
+{
+  float_coord new_c;
+
+  new_c.x = c.x - v.dx;
+  new_c.y = c.y - v.dy;
+  new_c.z = c.z - v.dz;
+  return new_c;
+}
+
+
+pm_pixelcoord
+Vadd_int_point(pm_pixelcoord const c,
+               vector_type   const v) {
+
+    pm_pixelcoord a;
+
+    a.col = ROUND ((float) c.col + v.dx);
+    a.row = ROUND ((float) c.row + v.dy);
+    
+    return a;
+}
+
+
+vector_type
+Vabs (const vector_type v)
+{
+  vector_type new_v;
+
+  new_v.dx = (float) fabs (v.dx);
+  new_v.dy = (float) fabs (v.dy);
+  new_v.dz = (float) fabs (v.dz);
+  return new_v;
+}
+
+
+/* Operations on points.  */
+
+float_coord
+Padd (const float_coord coord1, const float_coord coord2)
+{
+  float_coord sum;
+
+  sum.x = coord1.x + coord2.x;
+  sum.y = coord1.y + coord2.y;
+  sum.z = coord1.z + coord2.z;
+
+  return sum;
+}
+
+
+float_coord
+Pmult_scalar (const float_coord coord, const float r)
+{
+  float_coord answer;
+
+  answer.x = coord.x * r;
+  answer.y = coord.y * r;
+  answer.z = coord.z * r;
+
+  return answer;
+}
+
+
+vector_type
+Psubtract (const float_coord c1, const float_coord c2)
+{
+  vector_type v;
+
+  v.dx = c1.x - c2.x;
+  v.dy = c1.y - c2.y;
+  v.dz = c1.z - c2.z;
+
+  return v;
+}
+
+
+
+/* Operations on integer points.  */
+
+vector_type
+IPsubtract(pm_pixelcoord const coord1,
+           pm_pixelcoord const coord2) {
+
+    vector_type v;
+
+    v.dx = (int) (coord1.col - coord2.col);
+    v.dy = (int) (coord1.row - coord2.row);
+    v.dz = 0.0;
+    
+    return v;
+}
+
+
+
+static float
+acos_d (float v, at_exception_type * excep)
+{
+  float a;
+
+  if (epsilon_equal (v, 1.0))
+    v = 1.0;
+  else if (epsilon_equal (v, -1.0))
+    v = -1.0;
+
+  errno = 0;
+  a = (float) acos (v);
+  if (errno == ERANGE || errno == EDOM)
+    {
+      at_exception_fatal(excep, strerror(errno));
+      return 0.0;
+    }
+  
+  
+  return a * (float) 180.0 / (float) M_PI;
+}