1 files changed, 76 insertions, 0 deletions
diff --git a/src/uqm/velocity.h b/src/uqm/velocity.h
new file mode 100644
index 0000000..968e1f7
--- /dev/null
+++ b/src/uqm/velocity.h
@@ -0,0 +1,76 @@
+//Copyright Paul Reiche, Fred Ford. 1992-2002
+
+/*
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#ifndef UQM_VELOCITY_H_
+#define UQM_VELOCITY_H_
+
+#include <string.h> /* for memset */
+#include "libs/gfxlib.h"
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+typedef struct velocity_desc
+{
+	COUNT TravelAngle;
+	EXTENT vector;
+	EXTENT fract;
+	EXTENT error;
+	EXTENT incr;
+} VELOCITY_DESC;
+
+#define ZeroVelocityComponents(pv) memset(pv,0,sizeof (*(pv)))
+#define GetVelocityTravelAngle(pv) (pv)->TravelAngle
+
+extern void GetCurrentVelocityComponents (VELOCITY_DESC *velocityptr,
+		SIZE *pdx, SIZE *pdy);
+extern void GetNextVelocityComponents (VELOCITY_DESC *velocityptr,
+		SIZE *pdx, SIZE *pdy, COUNT num_frames);
+extern void SetVelocityVector (VELOCITY_DESC *velocityptr, SIZE magnitude,
+		COUNT facing);
+extern void SetVelocityComponents (VELOCITY_DESC *velocityptr, SIZE dx,
+		SIZE dy);
+extern void DeltaVelocityComponents (VELOCITY_DESC *velocityptr, SIZE dx,
+		SIZE dy);
+
+static inline bool
+IsVelocityZero (VELOCITY_DESC *vptr)
+{
+	return vptr->vector.width == 0 && vptr->vector.height == 0 &&
+			vptr->incr.width == 0 && vptr->incr.height == 0 &&
+			vptr->fract.width == 0 && vptr->fract.height == 0;
+}
+
+static inline DWORD
+VelocitySquared (SIZE dx, SIZE dy)
+{
+	return (DWORD)((long)dx * dx + (long)dy * dy);
+}
+
+#define VELOCITY_SHIFT 5
+#define VELOCITY_SCALE (1<<VELOCITY_SHIFT)
+
+#define VELOCITY_TO_WORLD(v) ((v)>>VELOCITY_SHIFT)
+#define WORLD_TO_VELOCITY(l) ((l)<<VELOCITY_SHIFT)
+
+#if defined(__cplusplus)
+}
+#endif
+
+#endif /* UQM_VELOCITY_H_ */