* Copyright 2006-2009, Haiku.
* Distributed under the terms of the MIT License.
*
* Authors:
* Stephan Aßmus <superstippi@gmx.de>
*/
#include "support.h"
#include <math.h>
#include <stdio.h>
#include <string.h>
#include <DataIO.h>
#include <Point.h>
#include <String.h>
double
point_line_distance(double x1, double y1, double x2, double y2, double x,
double y)
{
double dx = x2 - x1;
double dy = y2 - y1;
return ((x - x2) * dy - (y - y2) * dx) / sqrt(dx * dx + dy * dy);
}
double
point_line_distance(BPoint point, BPoint pa, BPoint pb)
{
double a = point_point_distance(point, pb);
double b = point_point_distance(point, pa);
double c = point_point_distance(pa, pb);
float currentDist = min_c(a, b);
if (a > 0.0 && b > 0.0) {
double alpha = acos((b*b + c*c - a*a) / (2*b*c));
double beta = acos((a*a + c*c - b*b) / (2*a*c));
if (alpha <= M_PI_2 && beta <= M_PI_2) {
currentDist = fabs(point_line_distance(pa.x, pa.y, pb.x, pb.y,
point.x, point.y));
}
}
return currentDist;
}
double
calc_angle(BPoint origin, BPoint from, BPoint to, bool degree)
{
double angle = 0.0;
double d = point_line_distance(from.x, from.y, origin.x, origin.y,
to.x, to.y);
if (d != 0.0) {
double a = point_point_distance(from, to);
double b = point_point_distance(from, origin);
double c = point_point_distance(to, origin);
if (a > 0.0 && b > 0.0 && c > 0.0) {
angle = acos((b*b + c*c - a*a) / (2.0*b*c));
if (d < 0.0)
angle = -angle;
if (degree)
angle = angle * 180.0 / M_PI;
}
}
return angle;
}
status_t
write_string(BPositionIO* stream, BString& string)
{
if (!stream)
return B_BAD_VALUE;
ssize_t written = stream->Write(string.String(), string.Length());
if (written > B_OK && written < string.Length())
written = B_ERROR;
string.SetTo("");
return written;
}
void
append_float(BString& string, float n, int32 maxDigits)
{
int32 rounded = n >= 0.0 ? (int32)fabs(floorf(n)) : (int32)fabs(ceilf(n));
if (n < 0.0) {
string << "-";
n *= -1.0;
}
string << rounded;
if ((float)rounded != n) {
n = n - rounded;
rounded = (int32)(n * pow(10, maxDigits));
char tmp[maxDigits + 1];
sprintf(tmp, "%0*" B_PRId32, (int)maxDigits, rounded);
tmp[maxDigits] = 0;
int32 digits = strlen(tmp);
for (int32 i = strlen(tmp) - 1; i >= 0; i--) {
if (tmp[i] == '0')
digits--;
else
break;
}
if (digits > 0) {
string << ".";
for (int32 i = 0; i < digits; i++) {
string << tmp[i];
}
}
}
}
