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-rw-r--r--app/bin/utility.c428
1 files changed, 206 insertions, 222 deletions
diff --git a/app/bin/utility.c b/app/bin/utility.c
index 93f9979..ff457d9 100644
--- a/app/bin/utility.c
+++ b/app/bin/utility.c
@@ -17,16 +17,9 @@
*
* 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.
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
-#include <stdlib.h>
-#include <stdio.h>
-#ifndef WINDOWS
-#include <unistd.h>
-#endif
-#include <math.h>
-#include "common.h"
#include "utility.h"
/*****************************************************************************
@@ -51,7 +44,7 @@ DEBUGF_T debugIntersection = 0;
#ifndef min
double max( double a, double b )
{
- if (a>b) return a;
+ if (a>b) { return a; }
return b;
}
@@ -59,13 +52,21 @@ double max( double a, double b )
double min( double a, double b )
{
- if (a<b) return a;
+ if (a<b) { return a; }
return b;
}
#endif
+int CoOrdEqual(coOrd p0, coOrd p1)
+{
+ double d = fabs(p1.x - p0.x) + fabs(p1.y - p0.y);
+ return (d < EPSILON);
+}
+
+
+
double FindDistance( coOrd p0, coOrd p1 )
{
double dx = p1.x-p0.x, dy = p1.y-p0.y;
@@ -76,24 +77,25 @@ double FindDistance( coOrd p0, coOrd p1 )
double NormalizeAngle( double a )
{
- while (a<0.0) a += 360.0;
- while (a>=360.0) a -= 360.0;
- if ( a > 360.0-EPSILON ) a = 0.0;
+ while (a<0.0) { a += 360.0; }
+ while (a>=360.0) { a -= 360.0; }
return a;
}
-double DifferenceBetweenAngles(double a, double b) {
- double difference = b - a;
- while (difference < -180) difference += 360;
- while (difference > 180) difference -= 360;
- return difference;
+double DifferenceBetweenAngles(double a, double b)
+{
+ double difference = b - a;
+ while (difference < -180) { difference += 360; }
+ while (difference > 180) { difference -= 360; }
+ return difference;
}
-int AngleInRange(double a, double start, double size) {
+int AngleInRange(double a, double start, double size)
+{
if (DifferenceBetweenAngles(start+size,a)<=0.0) {
- if (DifferenceBetweenAngles(start,a)>=0.0)
+ if (DifferenceBetweenAngles(start,a)>=0.0) {
return 0;
- else return 1;
+ } else { return 1; }
}
return -1;
}
@@ -110,7 +112,7 @@ int IsAligned( double a1, double a2 )
double D2R( double D )
{
D = NormalizeAngle(D);
- if (D >= 180.0) D = D - 360.0;
+ if (D >= 180.0) { D = D - 360.0; }
return D * (M_PI*2) / 360.0;
}
@@ -155,13 +157,10 @@ void Translate( coOrd *res, coOrd orig, double a, double d )
double FindAngle( coOrd p0, coOrd p1 )
{
double dx = p1.x-p0.x, dy = p1.y-p0.y;
- if (small(dx)) {
- if (dy >=0) return 0.0;
- else return 180.0;
- }
- if (small(dy)) {
- if (dx >=0) return 90.0;
- else return 270.0;
+ if ( dx == 0.0 && dy == 0.0 )
+ // Avoid implementation defined behavior
+ {
+ return 0.0;
}
return R2D(atan2( dx,dy ));
}
@@ -192,7 +191,8 @@ double ConstrainR( double r )
-void FindPos( coOrd * res, double * beyond, coOrd pos, coOrd orig, double angle, double length )
+void FindPos( coOrd * res, double * beyond, coOrd pos, coOrd orig, double angle,
+ double length )
{
double a0, a1;
double d;
@@ -212,7 +212,7 @@ void FindPos( coOrd * res, double * beyond, coOrd pos, coOrd orig, double angle,
} else {
res->x = (POS_T)x;
}
- if (beyond) *beyond = x - res->x;
+ if (beyond) { *beyond = x - res->x; }
res->y = (POS_T)(d * sin( D2R( a1 )) );
}
@@ -221,15 +221,18 @@ void FindPos( coOrd * res, double * beyond, coOrd pos, coOrd orig, double angle,
* Given two circles described by centers and radius (C1, R1) (C2, R2) Find the zero, one or two intersection points
*
*/
-BOOL_T FindArcIntersections ( coOrd *Pc, coOrd *Pc2, coOrd center1, DIST_T radius1, coOrd center2, DIST_T radius2) {
+BOOL_T FindArcIntersections ( coOrd *Pc, coOrd *Pc2, coOrd center1,
+ DIST_T radius1, coOrd center2, DIST_T radius2)
+{
double d,a,h;
- d = sqrt((center2.x-center1.x)*(center2.x-center1.x)+(center2.y-center1.y)*(center2.y-center1.y));
- if (d >(radius1+radius2)) return FALSE; //Too far apart
- if (d<fabs(radius1-radius2)) return FALSE; //Inside each other
- if ((d == 0) && (radius1 == radius2)) return FALSE; // Coincident and the same
+ d = sqrt((center2.x-center1.x)*(center2.x-center1.x)+(center2.y-center1.y)*
+ (center2.y-center1.y));
+ if (d >(radius1+radius2)) { return FALSE; } //Too far apart
+ if (d<fabs(radius1-radius2)) { return FALSE; } //Inside each other
+ if ((d == 0) && (radius1 == radius2)) { return FALSE; } // Coincident and the same
a=((radius1*radius1)-(radius2*radius2)+(d*d))/(2*d);
- if ((radius1*radius1)<(a*a)) return FALSE;
+ if ((radius1*radius1)<(a*a)) { return FALSE; }
h = sqrt((radius1*radius1)-(a*a));
coOrd center_c;
@@ -245,86 +248,47 @@ BOOL_T FindArcIntersections ( coOrd *Pc, coOrd *Pc2, coOrd center1, DIST_T radiu
}
/*
- * Find Intersections between a line and a circle
- *
- * |c-x|^2 = r^2
- *
- * 𝑥(𝑡)=𝑎+𝑡𝑏
- *
- * where 𝑎 is a point and 𝑏 is a vector.
- *
- * For a point on this line to satisfy the equation, you need to have
- *
- * (𝑡𝑏+(𝑎−𝑐))⋅(𝑡𝑏+(𝑎−𝑐))=𝑟^2
- *
- * which is a quadratic in 𝑡:
- * |b|^2*t^2 + 2(a-c).bt +(|a-c|^2-r^2) = 0
- *
- * whose solutions are
- *
- * t = (-2(a-c).b +/- SQRT([2(a-c).b]^2 - 4|b|^2(|a-c|^2-r^2)) / 2|b|^2
+ * Find Intersection between arc and line.
+ * First - move arc/circle and line so circle is at origin
+ * Then find nearest point on line to origin
+ * If nearest point is > radius -> no intersect
+ * If nearest point is == radius -> one point (the nearest)
+ * If nearest point is < radius -> two points
+ * Find two intersect points on secant by triangle formed between middle, center and arc point
*
*/
+BOOL_T FindArcAndLineIntersections(coOrd *intersection1, coOrd *intersection2,
+ coOrd c, DIST_T radius,
+ coOrd point1, coOrd point2 )
+{
+
+ double la, lb, lc; //Line equation
-double VectorLength (coOrd v) {
- return sqrt(v.x*v.x+v.y+v.y);
-}
-double VectorDot (coOrd v1, coOrd v2) {
- return (v1.x*v2.x+ v1.y*v2.y);
-}
-coOrd VectorSubtract (coOrd v1, coOrd v2) {
- coOrd result;
- result.x = v1.x-v2.x;
- result.y = v1.y-v2.y;
- return result;
-}
-coOrd VectorAdd (coOrd v1, coOrd v2) {
- coOrd result;
- result.x = v1.x+v2.x;
- result.y = v1.y+v2.y;
- return result;
-}
-
-BOOL_T FindArcAndLineIntersections(coOrd *intersection1, coOrd *intersection2, coOrd c, DIST_T radius,
- coOrd point1, coOrd point2 )
-{
- double dx, dy, cx, cy, A, B, C, det, t;
-
- dx = point2.x - point1.x;
- dy = point2.y - point1.y;
-
- cx = c.x;
- cy = c.y;
-
- A = dx * dx + dy * dy;
- B = 2 * (dx * (point1.x - cx) + dy * (point1.x - cy));
- C = (point1.x - cx) * (point1.x - cx) + (point1.y - cy) * (point1.y - cy) - radius * radius;
-
- det = B * B - 4 * A * C;
- if ((A <= 0.0000001) || (det < 0))
- {
- return FALSE;
- }
- else if (det == 0)
- {
- // One solution.
- t = -B / (2 * A);
- (*intersection1).x = point1.x + t * dx;
- (*intersection1).y = point1.y + t * dy;
- intersection2 = intersection1;
- return TRUE;
- }
- else
- {
- // Two solutions.
- t = (float)((-B + sqrt(det)) / (2 * A));
- (*intersection1).x = point1.x + t * dx;
- (*intersection1).y = point1.y + t * dy;
- t = (float)((-B - sqrt(det)) / (2 * A));
- (*intersection2).x = point1.x + t * dx;
- (*intersection2).y = point1.y + t * dy;
- return TRUE;
- }
+ la = point1.y - point2.y;
+ lb = point2.x - point1.x;
+ lc = (point1.x-c.x)*(point2.y-c.y) - (point2.x-c.x)*(point1.y
+ -c.y); //Move by c(x,y)
+
+ double x0 = -la*lc/(la*la+lb*lb), y0 = -lb*lc/(la*la+lb*lb);
+
+ double dis = radius*radius*(la*la+lb*lb);
+
+ if (lc*lc > dis) {
+ return FALSE;
+ } else if (fabs(lc*lc - dis) < EPSILON) {
+ (*intersection1).x = x0+c.x;
+ (*intersection1).y = y0+c.y;
+ *intersection2 = *intersection1;
+ return TRUE;
+ } else {
+ double d = radius*radius - lc*lc/(la*la+lb*lb);
+ double mult = sqrt(d/(la*la+lb*lb));
+ (*intersection1).x = x0+lb*mult+c.x;
+ (*intersection2).x = x0-lb*mult+c.x;
+ (*intersection1).y = y0-la*mult+c.y;
+ (*intersection2).y = y0+la*mult+c.y;
+ return TRUE;
+ }
}
/* Find intersection:
@@ -414,7 +378,7 @@ BOOL_T FindArcAndLineIntersections(coOrd *intersection1, coOrd *intersection2, c
d1x*d0y - d1y*d0x
if (d1x*d0y - d1y*d0x) = 0 then lines are parallel
-*/
+*/
BOOL_T FindIntersection( coOrd *Pc, coOrd P0, double A0, coOrd P1, double A1 )
{
@@ -424,7 +388,7 @@ BOOL_T FindIntersection( coOrd *Pc, coOrd P0, double A0, coOrd P1, double A1 )
#ifndef WINDOWS
if (debugIntersection >= 3)
printf("FindIntersection( [%0.3f %0.3f] A%0.3f [%0.3f %0.3f] A%0.3f\n",
- P0.x, P0.y, A0, P1.x, P1.y, A1 );
+ P0.x, P0.y, A0, P1.x, P1.y, A1 );
#endif
dx0 = sin( D2R( A0 ) );
@@ -434,21 +398,21 @@ BOOL_T FindIntersection( coOrd *Pc, coOrd P0, double A0, coOrd P1, double A1 )
d = dx1 * dy0 - dx0 * dy1;
if (d < EPSILON && d > -EPSILON) {
#ifndef WINDOWS
- if (debugIntersection >=3 ) printf("dx1 * dy0 - dx0 * dy1 = %0.3f\n", d );
+ if (debugIntersection >=3 ) { printf("dx1 * dy0 - dx0 * dy1 = %0.3f\n", d ); }
#endif
return FALSE;
}
-/*
- * (P0.x - P1.x) * d0y + (P1.y - P0.y) * d0x
- * N1 = =============================================
- * d1x*d0y - d1y*d0x
- */
+ /*
+ * (P0.x - P1.x) * d0y + (P1.y - P0.y) * d0x
+ * N1 = =============================================
+ * d1x*d0y - d1y*d0x
+ */
N1 = dy0 * (P0.x - P1.x) + dx0 * (P1.y - P0.y );
N1 = N1 / d;
Pc->x = P1.x + (POS_T)(N1*dx1);
Pc->y = P1.y + (POS_T)(N1*dy1);
#ifndef WINDOWS
- if (debugIntersection >=3 ) printf( " [%0.3f,%0.3f]\n", Pc->x, Pc->y );
+ if (debugIntersection >=3 ) { printf( " [%0.3f,%0.3f]\n", Pc->x, Pc->y ); }
#endif
return TRUE;
}
@@ -458,20 +422,22 @@ EPINX_T PickArcEndPt( coOrd pc, coOrd p0, coOrd p1 )
{
double a;
a = NormalizeAngle( FindAngle( pc, p1 ) - FindAngle( pc, p0 ) );
- if (a > 180.0)
+ if (a > 180.0) {
return 0;
- else
+ } else {
return 1;
+ }
}
EPINX_T PickLineEndPt( coOrd p0, double a0, coOrd p1 )
{
double a;
a = NormalizeAngle( FindAngle( p0, p1 ) - a0 );
- if (a < 90.0 || a > 270 )
+ if (a < 90.0 || a > 270 ) {
return 0;
- else
+ } else {
return 1;
+ }
}
double LineDistance( coOrd *p, coOrd p0, coOrd p1 )
@@ -526,6 +492,14 @@ double CircleDistance( coOrd *p, coOrd c, double r, double a0, double a1 )
+coOrd MidPtCoOrd(coOrd p0, coOrd p1)
+{
+ coOrd res;
+ res.x = (p0.x + p1.x) / 2.0;
+ res.y = (p0.y + p1.y) / 2.0;
+ return res;
+}
+
coOrd AddCoOrd( coOrd p0, coOrd p1, double a )
{
coOrd res, zero;
@@ -538,31 +512,34 @@ coOrd AddCoOrd( coOrd p0, coOrd p1, double a )
BOOL_T InRect( coOrd pos, coOrd rect )
{
- if (pos.x >= 0.0 && pos.x <= rect.x && pos.y >= 0.0 && pos.y <= rect.y)
+ if (pos.x >= 0.0 && pos.x <= rect.x && pos.y >= 0.0 && pos.y <= rect.y) {
return 1;
- else
+ } else {
return 0;
+ }
}
-static BOOL_T IntersectLine( POS_T *fx0, POS_T *fy0, POS_T x1, POS_T y1, POS_T x, POS_T y )
+static BOOL_T IntersectLine( POS_T *fx0, POS_T *fy0, POS_T x1, POS_T y1,
+ POS_T x, POS_T y )
{
POS_T x0=*fx0, y0=*fy0, dx, dy;
BOOL_T rc;
#ifdef TEST
printf(" IntersectLine( P0=[%0.2f %0.2f] P1=[%0.2f %0.2f] X=%0.2f Y=%0.2f\n",
- x0, y0, x1, y1, x, y );
+ x0, y0, x1, y1, x, y );
#endif
dx = x1-x0;
dy = y1-y0;
if (dy==0.0) {
- if (y0 == y)
+ if (y0 == y) {
rc = TRUE;
- else
+ } else {
rc = FALSE;
+ }
} else {
x0 += (y-y0) * dx/dy;
- if (x0 < -EPSILON || x0 > x) {
+ if (x0 < -EPSILON || x0 > (x+EPSILON)) {
rc = FALSE;
} else {
*fx0 = x0;
@@ -571,10 +548,11 @@ static BOOL_T IntersectLine( POS_T *fx0, POS_T *fy0, POS_T x1, POS_T y1, POS_T x
}
}
#ifdef TEST
- if (rc)
+ if (rc) {
printf(" = TRUE [%0.2f %0.2f]\n", *fx0, *fy0 );
- else
+ } else {
printf(" = FALSE\n");
+ }
#endif
return rc;
}
@@ -587,19 +565,18 @@ static void IntersectBox( coOrd *p1, coOrd p0, coOrd size, int x1, int y1 )
{
#ifdef TEST
printf(" IntersectBox( P1=[%0.2f %0.2f] P0=[%0.2f %0.2f] S=[%0.2f %0.2f] X1=%d Y1=%d\n",
- p1->x, p1->y, p0.x, p0.y, size.x, size.y, x1, y1 );
+ p1->x, p1->y, p0.x, p0.y, size.x, size.y, x1, y1 );
#endif
if ( y1!=0 &&
- IntersectLine( &p1->x, &p1->y, p0.x, p0.y, size.x, (y1==-1?(POS_T)0.0:size.y) ))
+ IntersectLine( &p1->x, &p1->y, p0.x, p0.y, size.x,
+ (y1==-1?(POS_T)0.0:size.y) )) {
return;
- else if ( x1!=0 &&
- IntersectLine( &p1->y, &p1->x, p0.y, p0.x, size.y, (x1==-1?(POS_T)0.0:size.x) ))
+ } else if ( x1!=0 &&
+ IntersectLine( &p1->y, &p1->x, p0.y, p0.x, size.y,
+ (x1==-1?(POS_T)0.0:size.x) )) {
return;
-#ifndef WINDOWS
- else
- fprintf(stderr, "intersectBox bogus\n" );
- getchar();
-#endif
+ }
+ printf(" intersectBox bogus\n" );
}
BOOL_T ClipLine( coOrd *fp0, coOrd *fp1, coOrd orig, double angle, coOrd size )
@@ -609,7 +586,7 @@ BOOL_T ClipLine( coOrd *fp0, coOrd *fp1, coOrd orig, double angle, coOrd size )
#ifdef TEST
printf("ClipLine( P0=[%0.2f %0.2f] P1=[%0.2f %0.2f] O=[%0.2f %0.2f] A=%0.2f S=[%0.2f %0.2f]\n",
- p0.x, p0.y, p1.x, p1.y, orig.x, orig.y, angle, size.x, size.y );
+ p0.x, p0.y, p1.x, p1.y, orig.x, orig.y, angle, size.x, size.y );
#endif
Rotate( &p0, orig, -angle );
@@ -624,18 +601,18 @@ BOOL_T ClipLine( coOrd *fp0, coOrd *fp1, coOrd orig, double angle, coOrd size )
------------O-------------+----------
-1,-1 | 0,-1 + 1,-1
*/
- if ( p0.x < 0.0-EPSILON ) x0 = -1;
- else if ( p0.x > size.x+EPSILON ) x0 = 1;
- else x0 = 0;
- if ( p0.y < 0.0-EPSILON ) y0 = -1;
- else if ( p0.y > size.y+EPSILON ) y0 = 1;
- else y0 = 0;
- if ( p1.x < 0.0-EPSILON ) x1 = -1;
- else if ( p1.x > size.x+EPSILON ) x1 = 1;
- else x1 = 0;
- if ( p1.y < 0.0-EPSILON ) y1 = -1;
- else if ( p1.y > size.y+EPSILON ) y1 = 1;
- else y1 = 0;
+ if ( p0.x < 0.0-EPSILON ) { x0 = -1; }
+ else if ( p0.x > size.x+EPSILON ) { x0 = 1; }
+ else { x0 = 0; }
+ if ( p0.y < 0.0-EPSILON ) { y0 = -1; }
+ else if ( p0.y > size.y+EPSILON ) { y0 = 1; }
+ else { y0 = 0; }
+ if ( p1.x < 0.0-EPSILON ) { x1 = -1; }
+ else if ( p1.x > size.x+EPSILON ) { x1 = 1; }
+ else { x1 = 0; }
+ if ( p1.y < 0.0-EPSILON ) { y1 = -1; }
+ else if ( p1.y > size.y+EPSILON ) { y1 = 1; }
+ else { y1 = 0; }
#ifdef TEST
printf(" X0=%d Y0=%d X1=%d Y1=%d\n", x0, y0, x1, y1 );
@@ -665,10 +642,12 @@ BOOL_T ClipLine( coOrd *fp0, coOrd *fp1, coOrd orig, double angle, coOrd size )
}
/* both points without box and cannot intersect */
- if ( (x0==x1 && y0==y1) || /* within same sector (but not the middle one) */
- (x0!=0 && x0==x1) || /* both right or left */
- (y0!=0 && y0==y1) ) /* both above or below */
+ if ( (x0==x1 && y0==y1 && x0!=0 && y0!=0)
+ || /* within same sector (but not the middle one) */
+ (x0!=0 && x0==x1) || /* both right or left */
+ (y0!=0 && y0==y1) ) { /* both above or below */
return 0;
+ }
#ifdef TEST
printf(" complex intersection\n");
@@ -676,18 +655,18 @@ BOOL_T ClipLine( coOrd *fp0, coOrd *fp1, coOrd orig, double angle, coOrd size )
/* possible intersection */
if ( y0!=0 &&
- IntersectLine( &p0.x, &p0.y, p1.x, p1.y, size.x, (y0==-1?(POS_T)0.0:size.y) ))
+ IntersectLine( &p0.x, &p0.y, p1.x, p1.y, size.x, (y0==-1?(POS_T)0.0:size.y) )) {
IntersectBox( &p1, p0, size, x1, y1 );
- else if ( y1!=0 &&
- IntersectLine( &p1.x, &p1.y, p0.x, p0.y, size.x, (y1==-1?(POS_T)0.0:size.y) ))
+ } else if ( y1!=0 &&
+ IntersectLine( &p1.x, &p1.y, p0.x, p0.y, size.x, (y1==-1?(POS_T)0.0:size.y) )) {
IntersectBox( &p0, p1, size, x0, y0 );
- else if ( x0!=0 &&
- IntersectLine( &p0.y, &p0.x, p1.y, p1.x, size.y, (x0==-1?(POS_T)0.0:size.x) ))
+ } else if ( x0!=0 &&
+ IntersectLine( &p0.y, &p0.x, p1.y, p1.x, size.y, (x0==-1?(POS_T)0.0:size.x) )) {
IntersectBox( &p1, p0, size, x1, y1 );
- else if ( x1!=0 &&
- IntersectLine( &p1.y, &p1.x, p0.y, p0.x, size.y, (x1==-1?(POS_T)0.0:size.x) ))
+ } else if ( x1!=0 &&
+ IntersectLine( &p1.y, &p1.x, p0.y, p0.x, size.y, (x1==-1?(POS_T)0.0:size.x) )) {
IntersectBox( &p0, p1, size, x0, y0 );
- else {
+ } else {
return 0;
}
p0.x += orig.x; p0.y += orig.y;
@@ -701,59 +680,59 @@ BOOL_T ClipLine( coOrd *fp0, coOrd *fp1, coOrd orig, double angle, coOrd size )
coOrd FindCentroid(int vertexCount, pts_t vertices[] )
{
- coOrd centroid = {0, 0};
- double signedArea = 0.0;
- double x0 = 0.0; // Current vertex X
- double y0 = 0.0; // Current vertex Y
- double x1 = 0.0; // Next vertex X
- double y1 = 0.0; // Next vertex Y
- double a = 0.0; // Partial signed area
-
- // For all vertices except last
- int i=0;
- for (i=0; i<vertexCount-1; ++i)
- {
- x0 = vertices[i].pt.x;
- y0 = vertices[i].pt.y;
- x1 = vertices[i+1].pt.x;
- y1 = vertices[i+1].pt.y;
- a = x0*y1 - x1*y0;
- signedArea += a;
- centroid.x += (x0 + x1)*a;
- centroid.y += (y0 + y1)*a;
- }
-
- // Do last vertex separately to avoid performing an expensive
- // modulus operation in each iteration.
- x0 = vertices[i].pt.x;
- y0 = vertices[i].pt.y;
- x1 = vertices[0].pt.x;
- y1 = vertices[0].pt.y;
- a = x0*y1 - x1*y0;
- signedArea += a;
- centroid.x += (x0 + x1)*a;
- centroid.y += (y0 + y1)*a;
-
- signedArea *= 0.5;
- centroid.x /= (6.0*signedArea);
- centroid.y /= (6.0*signedArea);
-
- return centroid;
+ coOrd centroid = {0, 0};
+ double signedArea = 0.0;
+ double x0 = 0.0; // Current vertex X
+ double y0 = 0.0; // Current vertex Y
+ double x1 = 0.0; // Next vertex X
+ double y1 = 0.0; // Next vertex Y
+ double a = 0.0; // Partial signed area
+
+ // For all vertices except last
+ int i=0;
+ for (i=0; i<vertexCount-1; ++i) {
+ x0 = vertices[i].pt.x;
+ y0 = vertices[i].pt.y;
+ x1 = vertices[i+1].pt.x;
+ y1 = vertices[i+1].pt.y;
+ a = x0*y1 - x1*y0;
+ signedArea += a;
+ centroid.x += (x0 + x1)*a;
+ centroid.y += (y0 + y1)*a;
+ }
+
+ // Do last vertex separately to avoid performing an expensive
+ // modulus operation in each iteration.
+ x0 = vertices[i].pt.x;
+ y0 = vertices[i].pt.y;
+ x1 = vertices[0].pt.x;
+ y1 = vertices[0].pt.y;
+ a = x0*y1 - x1*y0;
+ signedArea += a;
+ centroid.x += (x0 + x1)*a;
+ centroid.y += (y0 + y1)*a;
+
+ signedArea *= 0.5;
+ centroid.x /= (6.0*signedArea);
+ centroid.y /= (6.0*signedArea);
+
+ return centroid;
}
double FindArcCenter(
- coOrd * pos,
- coOrd p0,
- coOrd p1,
- double radius )
+ coOrd * pos,
+ coOrd p0,
+ coOrd p1,
+ double radius )
{
double d;
double a0, a1;
d = FindDistance( p0, p1 )/2.0;
a0 = FindAngle( p0, p1 );
a1 = NormalizeAngle(R2D(asin( d/radius )));
- if (a1 > 180)
+ if (a1 > 180) {
a1 -= 360;
+ }
a0 = NormalizeAngle( a0 + (90.0-a1) );
Translate( pos, p0, a0, radius );
return a1*2.0;
@@ -761,21 +740,24 @@ double FindArcCenter(
#ifdef LATER
-BOOL_T ClipArc( double a0, double a1, coOrd pos, double radius, coOrd orig, double angle, double size )
+BOOL_T ClipArc( double a0, double a1, coOrd pos, double radius, coOrd orig,
+ double angle, double size )
{
i = -1;
state = unknown;
if (pos.y + radius < 0.0 ||
- pos.y - radius > size.y ||
- pos.x + radius < 0.0 ||
- pos.x - radius > size.x )
+ pos.y - radius > size.y ||
+ pos.x + radius < 0.0 ||
+ pos.x - radius > size.x ) {
return 0;
+ }
if (pos.y + radius <= size.y ||
- pos.y - radius >= 0.0 ||
- pos.x + radius <= size.x ||
- pos.x - radius >= 0.0 )
+ pos.y - radius >= 0.0 ||
+ pos.x + radius <= size.x ||
+ pos.x - radius >= 0.0 ) {
return 1;
+ }
if (pos.y + radius > size.y) {
a = R2D(acos( (size.y-pos.y) / radius ) ));
@@ -795,7 +777,8 @@ BOOL_T ClipArc( double a0, double a1, coOrd pos, double radius, coOrd orig, doub
#endif
#ifdef TEST
-void Test( double p0x, double p0y, double p1x, double p1y, double origx, double origy, double angle, double sizex, double sizey )
+void Test( double p0x, double p0y, double p1x, double p1y, double origx,
+ double origy, double angle, double sizex, double sizey )
{
coOrd p0, p1, orig, size, p0a, p1a;
@@ -806,7 +789,7 @@ void Test( double p0x, double p0y, double p1x, double p1y, double origx, double
p0a = p0; p1a = p1;
rc = ClipLine( &p0, &p1, orig, angle, size );
printf("clipLine=%d P0=[%0.3f %0.3f] P1=[%0.3f %0.3f]\n", rc,
- p0.x, p0.y, p1.x, p1.y );
+ p0.x, p0.y, p1.x, p1.y );
}
INT_T Main( INT_T argc, char *argv[] )
@@ -818,8 +801,9 @@ INT_T Main( INT_T argc, char *argv[] )
Exit(1);
}
argv++;
- for (i=0;i<9;i++)
+ for (i=0; i<9; i++) {
a[i] = atof( *argv++ );
+ }
Test( a[0], a[1], a[2], a[3], a[4], a[5], a[6], a[7], a[8] );
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-15 15:50:09 +0000