fpoint.h

Go to the documentation of this file.

/******************************************************************************
 ** Filename:    fpoint.h
 ** Purpose:     Abstract data type for 2D points (floating point coords)
 ** Author:      Dan Johnson
 **
 ** (c) Copyright Hewlett-Packard Company, 1988.
 ** (c) Copyright Hewlett-Packard Company, 1988.
 ** Licensed under the Apache License, Version 2.0 (the "License");
 ** you may not use this file except in compliance with the License.
 ** You may obtain a copy of the License at
 ** http://www.apache.org/licenses/LICENSE-2.0
 ** Unless required by applicable law or agreed to in writing, software
 ** distributed under the License is distributed on an "AS IS" BASIS,
 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 ** See the License for the specific language governing permissions and
 ** limitations under the License.
 ******************************************************************************/
 
#ifndef FPOINT_H
#define FPOINT_H
 
#include <cmath>
#include <cstdio>
 
/* define data structure to hold 2D points or vectors using floating point */
typedef struct {
  float x, y;
} FPOINT;
using FVECTOR = FPOINT;
 
/* macros for computing miscellaneous functions of 2 points */
#define XDelta(A, B) ((B).x - (A).x)
#define YDelta(A, B) ((B).y - (A).y)
#define SlopeFrom(A, B) (YDelta(A, B) / XDelta(A, B))
#define AngleFrom(A, B) (atan2((double)YDelta(A, B), (double)XDelta(A, B)))
 
#define XIntersectionOf(A, B, X) (SlopeFrom(A, B) * ((X)-A.x) + A.y)
 
/*-------------------------------------------------------------------------
        Public Function Prototypes
---------------------------------------------------------------------------*/
 
float DistanceBetween(FPOINT A, FPOINT B);
 
float NormalizedAngleFrom(FPOINT* Point1, FPOINT* Point2, float FullScale);
 
#endif