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-rw-r--r--src/3rdparty/autotrace/epsilon-equal.c22
1 files changed, 22 insertions, 0 deletions
diff --git a/src/3rdparty/autotrace/epsilon-equal.c b/src/3rdparty/autotrace/epsilon-equal.c
new file mode 100644
index 0000000..8d26886
--- /dev/null
+++ b/src/3rdparty/autotrace/epsilon-equal.c
@@ -0,0 +1,22 @@
+/* epsilon-equal.c: define a error resist compare. */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif /* Def: HAVE_CONFIG_H */
+
+#include "types.h"
+#include "epsilon-equal.h"
+#include <math.h>
+
+/* Numerical errors sometimes make a floating point number just slightly
+ larger or smaller than its TRUE value. When it matters, we need to
+ compare with some tolerance, REAL_EPSILON, defined in kbase.h. */
+
+gboolean epsilon_equal(gfloat v1, gfloat v2)
+{
+ if (v1 == v2 /* Usually they'll be exactly equal, anyway. */
+ || fabs(v1 - v2) <= REAL_EPSILON)
+ return TRUE;
+
+ return FALSE;
+}