/** \file cbezier.c
* Bezier Command. Draw or modify a Bezier (Track or Line).
*/
/* XTrkCad - Model Railroad CAD
*
* Cubic Bezier curves have a definitional representation as an a set of four points.
* The first and fourth are the end points, while the middle two are control points.
* The control points positions define the angle at the ends and by their relative positions the overall
* curvature. This representation is a familiar approach for those who know drawing programs such as Adobe
* Illustrator or CorelDraw.
*
* In XTrackCAD, the Bezier form is also represented and drawn as a set of
* joined circular arcs that approximate the Bezier form within a small tolerance. This is because
* many of the operations we need to do are either computationally difficult or
* impossible using the Bezier equations. For example, creating a parallel Bezier
* which is necessary to draw a track with two lines or sleepers has no easy, stable solution.
* But the program is already able to do these tasks for straight lines and curves.
*
* Note that every time we change the Bezier points we have to recalculate the arc approximation,
* but that means that the majority of the time we are using the simpler approximation.
*
* We do not allow Bezier curves that have loops or cusps as they make no sense for tracks and
* can easily be approximated for lines with multiple unaligned Bezier curves.
*
* This program borrows from particular ideas about converting Bezier curves that Pomax placed into
* open source. The originals in Javascript can be found at github.com/Pomax.
* The web pages that explain many other techniques are located at https://pomax.github.io/bezierinfo
*
* 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.
*/
#include "track.h"
#include "draw.h"
#include "ccurve.h"
#include "cbezier.h"
#include "tbezier.h"
#include "cstraigh.h"
#include "drawgeom.h"
#include "cjoin.h"
#include "i18n.h"
#include "common.h"
#include "wcolors.h"
#include "math.h"
#include "utility.h"
#include "param.h"
#include "fileio.h"
#include "layout.h"
#include "cundo.h"
extern drawCmd_t tempD;
/*
* STATE INFO
*/
enum Bezier_States { NONE,
POS_1,
CONTROL_ARM_1,
POS_2,
CONTROL_ARM_2,
PICK_POINT,
POINT_PICKED,
TRACK_SELECTED };
typedef struct {
curveData_t curveData;
double start;
double end;
coOrd pos0;
coOrd pos1;
} bCurveData_t;
static struct {
enum Bezier_States state;
coOrd pos[4];
int selectPoint;
wDrawColor color;
DIST_T width;
track_p trk[2];
EPINX_T ep[2];
dynArr_t crvSegs_da;
int crvSegs_da_cnt;
trkSeg_t cp1Segs_da[4];
int cp1Segs_da_cnt;
trkSeg_t cp2Segs_da[4];
int cp2Segs_da_cnt;
BOOL_T unlocked;
track_p selectTrack;
BOOL_T track;
DIST_T minRadius;
DIST_T trackGauge;
} Da;
/**
* Draw a ControlArm.
* A control arm has two filled or unfilled circles for endpoints and a straight line between them.
* If the end or control point is not selectable we don't mark it with a circle.
* If a selectable end or control point is unlocked place a filled circle on it, otherwise an empty circle.
* A red color indicates that this arm, end or control point is "active" as it was selected.
*/
int createControlArm(
trkSeg_t sp[], //seg pointer for up to 3 trkSegs (ends and line)
coOrd pos0, //end on curve
coOrd pos1, // control point at other end of line
BOOL_T track, // isTrack()? (otherwise Line)
BOOL_T selectable, // can this arm be selected?
BOOL_T cp_direction_locked, //isFixed to track
int point_selected, //number of point 0, 1 or -1
wDrawColor color //drawColorBlack or drawColorWhite
)
{
DIST_T d, w;
d = tempD.scale*0.25;
w = tempD.scale/tempD.dpi; /*double width*/
sp[0].u.l.pos[0] = pos0;
sp[0].u.l.pos[1] = pos1;
sp[0].type = SEG_STRLIN;
sp[0].width = w;
sp[0].color = (point_selected>=0)?drawColorRed:drawColorBlack;
int n = 0;
if (selectable) {
for (int j=0;j<2;j++) {
if (j==0 && cp_direction_locked) continue; //Don't show select circle if end locked
n++;
sp[n].u.c.center = j==0?pos0:pos1;
sp[n].u.c.radius = d/4;
sp[n].width = w;
sp[n].color = (j==point_selected)?drawColorRed:drawColorBlack;
if (j==point_selected && cp_direction_locked) {
sp[n].type = SEG_FILCRCL;
} else {
sp[n].type = SEG_CRVLIN;
sp[n].u.c.a0 = 0.0;
sp[n].u.c.a1 = 360.0;
}
}
}
return n+1;
}
coOrd getPoint(coOrd pos[4], double s) {
double mt = 1-s;
double a = mt*mt*mt;
double b = mt*mt*s*3;
double c = mt*s*s*3;
double d = s*s*s;
coOrd ret;
ret.x = a*pos[0].x + b*pos[1].x + c*pos[2].x + d*pos[3].x;
ret.y = a*pos[0].y + b*pos[1].y + c*pos[2].y + d*pos[3].y;
return ret;
}
/*
* Get Error between a Bezier and an arc centered at pc that goes from start to end
*
* Because the curve is defined to pass through the start and the end and the middle, the test is
* to see how much of an error there is between those points. If the sum of the errors is off by more \
* than 0.5 pixels - that will mean it is not a good fit.
*
*/
double BezError(coOrd pos[4], coOrd center, coOrd start_point, double start, double end) {
double quarter = (end - start) / 4; // take point at 1/4 and 3/4 and check
coOrd c1 = getPoint(pos, start + quarter);
coOrd c2 = getPoint(pos, end - quarter);
double ref = FindDistance(center, start_point); //radius
double d1 = FindDistance(center, c1); // distance to quarter
double d2 = FindDistance(center, c2); // distance to three quarters
return fabs(d1-ref) + fabs(d2-ref); //total error at quarter points
};
/*
* Get distance between a point and a line segment
*/
double DistanceToLineSegment(coOrd p, coOrd l1, coOrd l2) {
double A = p.x - l1.x;
double B = p.y - l1.y;
double C = l2.x - l1.x;
double D = l2.y - l1.y;
double dot = A * C + B * D;
double len_sq = C * C + D * D;
double param = -1;
if (len_sq != 0) //non 0 length line
param = dot / len_sq;
double xx, yy;
if (param < 0) { // zero length line or beyond end use point 1
xx = l1.x;
yy = l1.y;
} else if (param > 1) { // beyond point 2 end of line segment
xx = l2.x;
yy = l2.y;
} else { // In the middle
xx = l1.x + param * C;
yy = l1.y + param * D;
}
double dx = p.x - xx; //distance to perpendicular (or end point)
double dy = p.y - yy;
return sqrt(dx * dx + dy * dy);
}
/*
* Get Error between a straight line segment and the Bezier curve.
* Sum distance to straight line of quarter points.
*/
double BezErrorLine(coOrd pos[4], coOrd start_point, coOrd end_point, double start, double end) {
double quarter = (end - start) / 4; // take point at 1/4 and 3/4 and check
coOrd c1 = getPoint(pos, start + quarter);
coOrd c2 = getPoint(pos, end - quarter);
double d1 = DistanceToLineSegment(c1, start_point, end_point);
double d2 = DistanceToLineSegment(c2, start_point, end_point);
return fabs(d1)+fabs(d2);
}
/*
* Add element to DYNARR pointed to by caller from segment handed in
*/
void addSegBezier(dynArr_t * const array_p, trkSeg_p seg) {
trkSeg_p s;
DYNARR_APPEND(trkSeg_t, * array_p, 1); //Adds 1 to cnt
s = &DYNARR_N(trkSeg_t,* array_p,array_p->cnt-1);
s->type = seg->type;
s->color = seg->color;
s->width = seg->width;
s->bezSegs.cnt = 0;
if (s->bezSegs.ptr) MyFree(s->bezSegs.ptr);
s->bezSegs.ptr=NULL;
s->bezSegs.max = 0;
if ((s->type == SEG_BEZLIN || s->type == SEG_BEZTRK) && seg->bezSegs.cnt) {
s->u.b.angle0 = seg->u.b.angle0; //Copy all the rest
s->u.b.angle3 = seg->u.b.angle3;
s->u.b.length = seg->u.b.length;
s->u.b.minRadius = seg->u.b.minRadius;
for (int i=0;i<4;i++) s->u.b.pos[i] = seg->u.b.pos[i];
s->u.b.radius0 = seg->u.b.radius3;
s->bezSegs.cnt = 0;
if (s->bezSegs.ptr) MyFree(s->bezSegs.ptr);
s->bezSegs.max = 0;
s->bezSegs.ptr = NULL; //Make sure new space as addr copied in earlier from seg
for (int i = 0; i<seg->bezSegs.cnt; i++) {
addSegBezier(&s->bezSegs,(((trkSeg_p)seg->bezSegs.ptr)+i)); //recurse for copying embedded Beziers as in Cornu joint
}
} else {
s->u = seg->u;
}
}
enum BezierType {PLAIN, LOOP, CUSP, INFLECTION, DOUBLEINFLECTION, LINE, ENDS, COINCIDENT } bType;
/*
* Analyse Bezier.
*
* Using results from Maureen C. Stone of XeroxParc and Tony deRose of U of Washington
* characterise the curve type and find out what features it has.
* We will eliminate cusps and loops as not useful forms. Line, Plain, Inflection and DoubleInflection are ok.
*
*/
EXPORT enum BezierType AnalyseCurve(coOrd inpos[4], double *Rfx, double *Rfy, double *cusp) {
*Rfx = *Rfy = 0;
if (Da.track && inpos[0].x == inpos[3].x && inpos[0].y == inpos[3].y ) {
return ENDS;
}
DIST_T d01 = FindDistance(inpos[0],inpos[1]);
DIST_T d12 = FindDistance(inpos[1],inpos[2]);
DIST_T d02 = FindDistance(inpos[0],inpos[2]);
if (d01+d12 == d02) { //straight
DIST_T d23 = FindDistance(inpos[2],inpos[3]);
DIST_T d03 = FindDistance(inpos[0],inpos[3]);
if (d02+d23 == d03) return LINE;
}
int common_points = 0;
for (int i=0;i<3;i++) {
if (inpos[i].x == inpos[i+1].x && inpos[i].y == inpos[i+1].y) common_points++;
}
for (int i=0;i<2;i++) {
if (inpos[i].x == inpos[i+2].x && inpos[i].y == inpos[i+2].y) common_points++;
}
if (common_points>2) {
return COINCIDENT;
}
coOrd pos[4];
coOrd offset2, offset = inpos[0];
for (int i=0;i<4;i++) { //move to zero origin
pos[i].x = inpos[i].x-offset.x;
pos[i].y = inpos[i].y-offset.y;
}
offset2.x = -offset.x + pos[3].x;
offset2.y = -offset.y + pos[3].y;
if (pos[1].y == 0.0) { //flip order of points
for (int i=0;i<4;i++) {
coOrd temp_pos = pos[i];
pos[i].x = pos[3-i].x - offset2.x;
pos[i].y = pos[3-i].y - offset2.y;
pos[3-i] = temp_pos;
}
if (pos[1].y == 0.0) { //Both ways round the second point has no y left after translation
return PLAIN;
}
}
double f21 = (pos[2].y)/(pos[1].y);
double f31 = (pos[3].y)/(pos[1].y);
if (fabs(pos[2].x-(pos[1].x*f21)) <0.0001) return PLAIN; //defend against divide by zero
double fx = (pos[3].x-(pos[1].x*f31))/(pos[2].x-(pos[1].x*f21));
double fy = f31+(1-f21)*fx;
*Rfx = fx;
*Rfy = fy;
*cusp = fabs(fy - (-(fx*fx)+2*fx+3)/4);
if (fy > 1.0) return INFLECTION;
if (fx >= 1.0) return PLAIN;
if (fabs(fy - (-(fx*fx)+2*fx+3)/4) <0.100) return CUSP;
if (fy < (-(fx*fx)+2*fx+3)/4) {
if (fx <= 0.0 && fy >= (3*fx-(fx*fx))/3) return LOOP;
if (fx > 0.0 && fy >= (sqrt(3*(4*fx-fx*fx))-fx)/2) return LOOP;
return PLAIN;
}
return DOUBLEINFLECTION;
}
/*
* ConvertToArcs
* Take a Bezier curve and turn it into a set of circular arcs, such that the error between the arc and the
* Bezier is under 0.5 pixels at maxiumum zoom.
*
* This enables us to use normal methods (operating over the array of arcs)
* to perform actions on the Bezier and also to export it to DXF.
*
*/
EXPORT BOOL_T ConvertToArcs (coOrd pos[4], dynArr_t * segs, BOOL_T track, wDrawColor color, DIST_T width) {
double t_s = 0.0, t_e = 1.0;
double errorThreshold = 0.05;
bCurveData_t prev_arc;
prev_arc.end = 0.0;
bCurveData_t arc;
segs->cnt = 0; //wipe out
BOOL_T safety;
int col = 0;
double prev_e = 0.0;
// we do a binary search to find the "good `t` closest to no-longer-good"
do {
safety=FALSE;
// step 1: start with the maximum possible arc length
t_e = 1.0;
// points:
coOrd start_point, mid_point, end_point;
// booleans:
BOOL_T curr_good = FALSE, prev_good = FALSE, done = FALSE;
// numbers:
double t_m, step = 0;
// step 2: find the best possible arc
do { // !done
prev_good = curr_good; //remember last time
t_m = (t_s + t_e)/2;
step++;
start_point = getPoint(pos, t_s); //Start of arc
mid_point = getPoint(pos, t_m); //Middle of trial arc
end_point = getPoint(pos, t_e); //End of trial Arc
PlotCurve( crvCmdFromChord, start_point, end_point, mid_point,
&(arc.curveData), TRUE ); //Find Arc through three points
arc.start = t_s; //remember start
arc.end = t_e; //remember end
arc.pos0 = start_point; //remember start point (used for Straight)
arc.pos1 = end_point; // Remember end point (used for Straight)
if (arc.curveData.type == curveTypeStraight) {
double error = BezErrorLine(pos,start_point,end_point, t_s, t_e);
curr_good = (error <= errorThreshold/2);
arc.curveData.a0 = FindAngle(start_point,end_point);
arc.curveData.a1 = FindAngle(end_point,start_point);
} else if (arc.curveData.type == curveTypeNone) {
return FALSE; //Something wrong
} else {
double error = BezError(pos, arc.curveData.curvePos, start_point, t_s, t_e);
curr_good = (error <= errorThreshold/2);
};
done = prev_good && !curr_good; //Was better than this last time?
if(!done) {
// this arc is fine: we can move 'e' up to see if we can find a wider arc
if(curr_good) {
prev_e = t_e; //remember good end only
prev_arc = arc;
// if e is already at max, then we're done for this arc.
if (t_e >= 1.0) {
// make sure we cap at t=1
arc.end = prev_e = 1.0;
// if we capped the arc segment to t=1 we also need to make sure that
// the arc's end angle is correct with respect to the bezier end point.
if (t_e > 1.0) {
if (arc.curveData.type != curveTypeStraight) {
coOrd d;
d.x = arc.curveData.curvePos.x + fabs(arc.curveData.curveRadius) * cos(D2R(arc.curveData.a1));
d.y = arc.curveData.curvePos.y + fabs(arc.curveData.curveRadius) * sin(D2R(arc.curveData.a1));
arc.curveData.a1 += FindAngle(d, getPoint(pos,1.0));
t_e = 1.0;
}
}
prev_arc = arc;
done = TRUE;
break;
}
// if not, move it up by half the iteration distance or to end
t_e = t_e + (t_e-t_s)/2;
if (t_e > 1.0) t_e = 1.0;
}
// this is a bad arc: we need to move 'e' down to find a good arc
else {
t_e = t_m;
}
} // If !Done end
} while(!done && safety++<100);
if(safety>=100) {
return FALSE; //Failed to make into arcs
}
prev_arc = prev_arc.end==0.0?arc:prev_arc;
trkSeg_t curveSeg; //Now set up tempSeg to copy into array
curveSeg.width = track?0:width;
if ( prev_arc.curveData.type == curveTypeCurve ) {
if (track)
curveSeg.color = (fabs(prev_arc.curveData.curveRadius)<(GetLayoutMinTrackRadius()-EPSILON))?wDrawColorRed:wDrawColorBlack;
else
curveSeg.color = color;
curveSeg.type = track?SEG_CRVTRK:SEG_CRVLIN;
curveSeg.u.c.a0 = prev_arc.curveData.a0;
curveSeg.u.c.a1 = prev_arc.curveData.a1;
curveSeg.u.c.center = prev_arc.curveData.curvePos;
if (prev_arc.curveData.negative)
curveSeg.u.c.radius = -prev_arc.curveData.curveRadius;
else
curveSeg.u.c.radius = prev_arc.curveData.curveRadius;
} else { //Straight Line because all points co-linear
curveSeg.type = track?SEG_STRTRK:SEG_STRLIN;
if (track)
curveSeg.color = wDrawColorBlack;
else
curveSeg.color = color;
curveSeg.u.l.angle = prev_arc.curveData.a1;
curveSeg.u.l.pos[0] = prev_arc.pos0;
curveSeg.u.l.pos[1] = prev_arc.pos1;
curveSeg.u.l.option = 0;
}
addSegBezier(segs, &curveSeg); //Add to array of segs used
t_s = prev_e;
col++;
} while(prev_e < 1.0);
return TRUE;
};
/*
* Draw Bezier while editing it. It consists of three elements - the curve and one or two control arms.
*
*/
EXPORT void DrawBezCurve(trkSeg_p control_arm1,
int cp1Segs_cnt,
trkSeg_p control_arm2,
int cp2Segs_cnt,
trkSeg_p curveSegs,
int crvSegs_cnt,
wDrawColor color
) {
long oldDrawOptions = tempD.funcs->options;
tempD.funcs->options = wDrawOptTemp;
long oldOptions = tempD.options;
tempD.options = DC_TICKS;
tempD.orig = mainD.orig;
tempD.angle = mainD.angle;
if (crvSegs_cnt && curveSegs)
DrawSegs( &tempD, zero, 0.0, curveSegs, crvSegs_cnt, Da.trackGauge, color );
if (cp1Segs_cnt && control_arm1)
DrawSegs( &tempD, zero, 0.0, control_arm1, cp1Segs_cnt, Da.trackGauge, drawColorBlack );
if (cp2Segs_cnt && control_arm2)
DrawSegs( &tempD, zero, 0.0, control_arm2, cp2Segs_cnt, Da.trackGauge, drawColorBlack );
tempD.funcs->options = oldDrawOptions;
tempD.options = oldOptions;
}
/*
* If Track, make it red if the radius is below minimum
*/
void DrawTempBezier(BOOL_T track) {
if (track) DrawBezCurve(Da.cp1Segs_da,Da.cp1Segs_da_cnt,Da.cp2Segs_da,Da.cp2Segs_da_cnt, (trkSeg_t *)Da.crvSegs_da.ptr,Da.crvSegs_da_cnt,Da.minRadius<(GetLayoutMinTrackRadius()-EPSILON)?drawColorRed:drawColorBlack);
else
DrawBezCurve(Da.cp1Segs_da,Da.cp1Segs_da_cnt,Da.cp2Segs_da,Da.cp2Segs_da_cnt, (trkSeg_t *)Da.crvSegs_da.ptr,Da.crvSegs_da_cnt,drawColorBlack); //Add Second Arm
}
void CreateBothControlArms(int selectPoint, BOOL_T track) {
if (selectPoint == -1) {
Da.cp1Segs_da_cnt = createControlArm(Da.cp1Segs_da, Da.pos[0],
Da.pos[1], track, TRUE, Da.trk[0]!=NULL, -1,
drawColorBlack);
Da.cp2Segs_da_cnt = createControlArm(Da.cp2Segs_da, Da.pos[3],
Da.pos[2], track, TRUE, Da.trk[1]!=NULL, -1,
drawColorBlack);
} else if (selectPoint == 0 || selectPoint == 1) {
Da.cp1Segs_da_cnt = createControlArm(Da.cp1Segs_da, Da.pos[0],
Da.pos[1], track, TRUE, Da.trk[0]!=NULL, selectPoint,
drawColorBlack);
Da.cp2Segs_da_cnt = createControlArm(Da.cp2Segs_da, Da.pos[3],
Da.pos[2], track, FALSE, Da.trk[1]!=NULL, -1,
drawColorBlack);
} else {
Da.cp1Segs_da_cnt = createControlArm(Da.cp1Segs_da, Da.pos[0],
Da.pos[1], track, FALSE, Da.trk[0]!=NULL, -1,
drawColorBlack);
Da.cp2Segs_da_cnt = createControlArm(Da.cp2Segs_da, Da.pos[3],
Da.pos[2], track, TRUE, Da.trk[1]!=NULL,
3-selectPoint, drawColorBlack);
}
}
/*
* AdjustBezCurve
*
* Called to adjust the curve either when creating it or modifying it
* States are "PICK_POINT" and "POINT_PICKED" and "TRACK_SELECTED".
*
* In PICK_POINT, the user can select an end-point to drag and release in POINT_PICKED. They can also
* hit Enter (which saves the changes) or ESC (which cancels them).
*
* Only those points which can be picked are shown with circles - locked end-points are not shown.
*
* SHIFT at release will lock , re-locking any end-points that are aligned with like items at the same position
* (Track to unconnected Track, Line to any Line end).
*
*/
EXPORT STATUS_T AdjustBezCurve(
wAction_t action,
coOrd pos,
BOOL_T track,
wDrawColor color,
DIST_T width,
bezMessageProc message )
{
track_p t;
DIST_T d;
ANGLE_T angle1, angle2;
static coOrd pos0, pos3, p;
enum BezierType b;
DIST_T dd;
EPINX_T ep;
double fx, fy, cusp;
int controlArm = -1;
if (Da.state != PICK_POINT && Da.state != POINT_PICKED && Da.state != TRACK_SELECTED) return C_CONTINUE;
switch ( action & 0xFF) {
case C_START:
Da.selectPoint = -1;
CreateBothControlArms(Da.selectPoint, track);
if (ConvertToArcs(Da.pos,&Da.crvSegs_da,track,color,Da.width)) Da.crvSegs_da_cnt = Da.crvSegs_da.cnt;
Da.minRadius = BezierMinRadius(Da.pos,Da.crvSegs_da);
Da.unlocked = FALSE;
if (track)
InfoMessage( _("Select End-Point - Ctrl unlocks end-point") );
else
InfoMessage( _("Select End-Point") );
DrawTempBezier(Da.track);
return C_CONTINUE;
case C_DOWN:
if (Da.state != PICK_POINT) return C_CONTINUE;
dd = 10000.0;
Da.selectPoint = -1;
DrawTempBezier(Da.track); //wipe out
for (int i=0;i<4;i++) {
d = FindDistance(Da.pos[i],pos);
if (d < dd) {
if (i==0 && Da.trk[0]) continue;
if (i==3 && Da.trk[1]) continue; //ignore locked points
dd = d;
Da.selectPoint = i;
}
}
if (!IsClose(dd) ) Da.selectPoint = -1;
if (Da.selectPoint == -1) {
InfoMessage( _("Not close enough to any valid, selectable point, reselect") );
DrawTempBezier(Da.track);
return C_CONTINUE;
} else {
pos = Da.pos[Da.selectPoint];
Da.state = POINT_PICKED;
InfoMessage( _("Drag point %d to new location and release it"),Da.selectPoint+1 );
}
CreateBothControlArms(Da.selectPoint, track);
if (ConvertToArcs(Da.pos, &Da.crvSegs_da, track, color,Da.width)) Da.crvSegs_da_cnt = Da.crvSegs_da.cnt;
Da.minRadius = BezierMinRadius(Da.pos, Da.crvSegs_da);
DrawTempBezier(Da.track);
return C_CONTINUE;
case C_MOVE:
if (Da.state != POINT_PICKED) {
InfoMessage(_("Pick any circle to adjust it - Enter to confirm, ESC to abort"));
return C_CONTINUE;
}
//If locked, reset pos to be on line from other track
DrawTempBezier(Da.track); //wipe out
if (Da.selectPoint == 1 || Da.selectPoint == 2) { //CPs
int controlArm = Da.selectPoint-1; //Snap to direction of track
if (Da.trk[controlArm]) {
angle1 = NormalizeAngle(GetTrkEndAngle(Da.trk[controlArm], Da.ep[controlArm]));
angle2 = NormalizeAngle(FindAngle(pos, Da.pos[Da.selectPoint==1?0:3])-angle1);
if (angle2 > 90.0 && angle2 < 270.0)
Translate( &pos, Da.pos[Da.selectPoint==1?0:3], angle1, -FindDistance( Da.pos[Da.selectPoint==1?0:3], pos )*cos(D2R(angle2)) );
else pos = Da.pos[Da.selectPoint==1?0:3];
} // Dont Snap control points
} else SnapPos(&pos);
Da.pos[Da.selectPoint] = pos;
CreateBothControlArms(Da.selectPoint, track);
if (ConvertToArcs(Da.pos,&Da.crvSegs_da,track, color, Da.width)) Da.crvSegs_da_cnt = Da.crvSegs_da.cnt;
Da.minRadius = BezierMinRadius(Da.pos,Da.crvSegs_da);
if (Da.track) {
b = AnalyseCurve(Da.pos,&fx,&fy,&cusp);
if (b==ENDS) {
wBeep();
InfoMessage(_("Bezier Curve Invalid has identical end points Change End Point"),b==CUSP?"Cusp":"Loop");
} else if ( b == CUSP || b == LOOP) {
wBeep();
InfoMessage(_("Bezier Curve Invalid has %s Change End Point"),b==CUSP?"Cusp":"Loop");
} else if ( b == COINCIDENT ) {
wBeep();
InfoMessage(_("Bezier Curve Invalid has three co-incident points"),b==CUSP?"Cusp":"Loop");
} else if ( b == LINE ) {
InfoMessage(_("Bezier is Straight Line"));
} else
InfoMessage( _("Bezier %s : Min Radius=%s Length=%s fx=%0.3f fy=%0.3f cusp=%0.3f"),track?"Track":"Line",
FormatDistance(Da.minRadius>=100000?0:Da.minRadius),
FormatDistance(BezierLength(Da.pos,Da.crvSegs_da)),fx,fy,cusp);
} else
InfoMessage( _("Bezier %s : Min Radius=%s Length=%s"),track?"Track":"Line",
FormatDistance(Da.minRadius>=100000?0:Da.minRadius),
FormatDistance(BezierLength(Da.pos,Da.crvSegs_da)));
DrawTempBezier(Da.track);
return C_CONTINUE;
case C_UP:
if (Da.state != POINT_PICKED) return C_CONTINUE;
//Take last pos and decide if it should be snapped to a track because SHIFT is held (pos0 and pos3)
ep = 0;
BOOL_T found = FALSE;
DrawTempBezier(Da.track); //wipe out
p = pos;
if (track && (Da.selectPoint == 0 || Da.selectPoint == 3)) { //EPs
if ((MyGetKeyState() & WKEY_SHIFT) != 0) { //Snap Track
if ((t = OnTrackIgnore(&p, FALSE, TRUE, Da.selectTrack)) != NULL) { //Snap to endPoint
ep = PickUnconnectedEndPointSilent(p, t);
if (ep != -1) {
Da.trk[Da.selectPoint/3] = t;
Da.ep[Da.selectPoint/3] = ep;
pos0 = Da.pos[(Da.selectPoint == 0)?1:2];
pos = GetTrkEndPos(t, ep);
found = TRUE;
}
} else {
wBeep();
InfoMessage(_("No unconnected End Point to lock to"));
}
}
}
if (found) {
angle1 = NormalizeAngle(GetTrkEndAngle(Da.trk[Da.selectPoint/3], Da.ep[Da.selectPoint/3]));
angle2 = NormalizeAngle(FindAngle(pos, pos0)-angle1);
Translate(&Da.pos[Da.selectPoint==0?1:2], Da.pos[Da.selectPoint==0?0:3], angle1, FindDistance(Da.pos[Da.selectPoint==0?1:2],pos)*cos(D2R(angle2)));
}
Da.selectPoint = -1;
CreateBothControlArms(Da.selectPoint,track);
if (ConvertToArcs(Da.pos,&Da.crvSegs_da,track,color,Da.width)) Da.crvSegs_da_cnt = Da.crvSegs_da.cnt;
Da.minRadius = BezierMinRadius(Da.pos,Da.crvSegs_da);
if (Da.track) {
b = AnalyseCurve(Da.pos,&fx,&fy,&cusp);
if (b==ENDS) {
wBeep();
InfoMessage(_("Bezier curve invalid has identical end points Change End Point"),b==CUSP?"Cusp":"Loop");
} else if ( b == CUSP || b == LOOP) {
wBeep();
InfoMessage(_("Bezier curve invalid has %s Change End Point"),b==CUSP?"Cusp":"Loop");
} else if ( b == COINCIDENT ) {
wBeep();
InfoMessage(_("Bezier curve invalid has three co-incident points"),b==CUSP?"Cusp":"Loop");
} else if ( b == LINE) {
InfoMessage(_("Bezier curve is straight line"));
}
InfoMessage(_("Pick any circle to adjust it - Enter to confirm, ESC to abort"));
} else
InfoMessage(_("Pick any circle to adjust it - Enter to confirm, ESC to abort"));
DrawTempBezier(Da.track);
Da.state = PICK_POINT;
return C_CONTINUE;
case C_OK: //C_OK is not called by Modify.
if ( Da.state == PICK_POINT ) {
char c = (unsigned char)(action >> 8);
if (Da.track && Da.pos[0].x == Da.pos[3].x && Da.pos[0].y == Da.pos[3].y ) {
wBeep();
ErrorMessage(_("Invalid Bezier Track - end points are identical"));
return C_CONTINUE;
}
if (Da.track) {
b = AnalyseCurve(Da.pos,&fx,&fy,&cusp);
if ( b == CUSP || b == LOOP ) {
wBeep();
ErrorMessage(_("Invalid Bezier Curve has a %s - Adjust"),b==CUSP?"Cusp":"Loop");
return C_CONTINUE;
} else if (b==COINCIDENT) {
wBeep();
ErrorMessage(_("Invalid Bezier Curve has three coincident points - Adjust"));
return C_CONTINUE;
} else if(b==ENDS) {
ErrorMessage(_("Invalid Bezier Track - end points are identical"));
return C_CONTINUE;
}
}
Da.minRadius = BezierMinRadius(Da.pos,Da.crvSegs_da);
DrawTempBezier(Da.track);
UndoStart( _("Create Bezier"), "newBezier - CR" );
if (Da.track) {
t = NewBezierTrack( Da.pos, (trkSeg_p)Da.crvSegs_da.ptr, Da.crvSegs_da.cnt);
for (int i=0;i<2;i++)
if (Da.trk[i] != NULL) ConnectAbuttingTracks(t,i,Da.trk[i],Da.ep[i]);
}
else t = NewBezierLine(Da.pos, (trkSeg_p)Da.crvSegs_da.ptr, Da.crvSegs_da.cnt,color,width);
UndoEnd();
if (Da.crvSegs_da.ptr) MyFree(Da.crvSegs_da.ptr);
Da.crvSegs_da.ptr = NULL;
Da.crvSegs_da.cnt = 0;
Da.crvSegs_da.max = 0;
DrawNewTrack(t);
Da.state = NONE;
MainRedraw();
MapRedraw();
return C_TERMINATE;
}
return C_CONTINUE;
case C_REDRAW:
DrawTempBezier(Da.track);
return C_CONTINUE;
default:
return C_CONTINUE;
}
}
struct extraData {
BezierData_t bezierData;
};
/*
* CmdBezModify
*
* Called from Modify Command - this function deals with the real (old) track and calls AdjustBezCurve to tune up the new one
* Sequence is this -
* - The C_START is called from CmdModify C_DOWN action if a track has being selected. The old track is hidden, the editable one is shown.
* - C_MOVES will be ignored until a C_UP ends the track selection and moves the state to PICK_POINT,
* - C_DOWN then hides the track and shows the Bezier handles version. Selects a point (if close enough and available) and the state moves to POINT_PICKED
* - C_MOVE drags the point around modifying the curve
* - C_UP puts the state back to PICK_POINT (pick another)
* - C_OK (Enter/Space) creates the new track, deletes the old and shows the changed track.
* - C_CANCEL (Esc) sets the state to NONE and reshows the original track unchanged.
*
* Note: Available points are shown - if a Bezier track is attached to its neighbor, only the control point on that side is selectable.
* Any free end-point can be locked to a unconnected end point using SHIFT during drag.
*/
STATUS_T CmdBezModify (track_p trk, wAction_t action, coOrd pos, DIST_T trackG) {
BOOL_T track = TRUE;
track_p t;
double width = 1.0;
long mode = 0;
long cmd;
struct extraData *xx = GetTrkExtraData(trk);
cmd = (long)commandContext;
Da.trackGauge = trackG;
switch (action&0xFF) {
case C_START:
Da.state = NONE;
DYNARR_RESET(trkSeg_t,Da.crvSegs_da);
Da.cp1Segs_da_cnt = 0;
Da.cp2Segs_da_cnt = 0;
Da.selectPoint = -1;
Da.selectTrack = NULL;
if (IsTrack(trk)) Da.track = TRUE;
else Da.track = FALSE;
Da.selectTrack = trk;
Da.trk[0] = GetTrkEndTrk( trk, 0 );
if (Da.trk[0]) Da.ep[0] = GetEndPtConnectedToMe(Da.trk[0],trk);
Da.trk[1] = GetTrkEndTrk( trk, 1 );
if (Da.trk[1]) Da.ep[1] = GetEndPtConnectedToMe(Da.trk[1],trk);
for (int i=0;i<4;i++) Da.pos[i] = xx->bezierData.pos[i]; //Copy parms from old trk
InfoMessage(_("%s picked - now select a Point"),track?"Track":"Line");
Da.state = TRACK_SELECTED;
DrawTrack(Da.selectTrack,&mainD,wDrawColorWhite); //Wipe out real track, draw replacement
return AdjustBezCurve(C_START, pos, Da.track, xx->bezierData.segsColor, xx->bezierData.segsWidth, InfoMessage);
case C_DOWN:
if (Da.state == TRACK_SELECTED) return C_CONTINUE; //Ignore until first up
return AdjustBezCurve(C_DOWN, pos, Da.track, xx->bezierData.segsColor, xx->bezierData.segsWidth, InfoMessage);
case C_MOVE:
if (Da.state == TRACK_SELECTED) return C_CONTINUE; //Ignore until first up and down
return AdjustBezCurve(C_MOVE, pos, Da.track, xx->bezierData.segsColor, xx->bezierData.segsWidth, InfoMessage);
case C_UP:
if (Da.state == TRACK_SELECTED) {
Da.state = PICK_POINT; //First time up, next time pick a point
}
return AdjustBezCurve(C_UP, pos, Da.track, xx->bezierData.segsColor, xx->bezierData.segsWidth, InfoMessage); //Run Adjust
case C_TEXT:
if ((action>>8) != 32)
return C_CONTINUE;
/* no break */
case C_OK:
if (Da.state != PICK_POINT) { //Too early - abandon
InfoMessage(_("No changes made"));
Da.state = NONE;
return C_CANCEL;
}
UndoStart( _("Modify Bezier"), "newBezier - CR" );
if (Da.track) t = NewBezierTrack( Da.pos, (trkSeg_p)Da.crvSegs_da.ptr, Da.crvSegs_da.cnt);
else t = NewBezierLine(Da.pos, (trkSeg_p)Da.crvSegs_da.ptr, Da.crvSegs_da.cnt,xx->bezierData.segsColor,xx->bezierData.segsWidth);
if (Da.track) CopyAttributes( trk, t );
DeleteTrack(trk, TRUE);
if (Da.track) {
for (int i=0;i<2;i++) { //Attach new track
if (Da.trk[i] != NULL && Da.ep[i] != -1) { //Like the old track
ConnectAbuttingTracks(t,i,Da.trk[i],Da.ep[i]);
}
}
}
UndoEnd();
InfoMessage(_("Modify Bezier Complete - select another"));
Da.state = NONE;
return C_TERMINATE;
case C_CANCEL:
InfoMessage(_("Modify Bezier Cancelled"));
Da.state = NONE;
MainRedraw();
MapRedraw();
return C_TERMINATE;
case C_REDRAW:
return AdjustBezCurve(C_REDRAW, pos, Da.track, xx->bezierData.segsColor, xx->bezierData.segsWidth, InfoMessage);
}
return C_CONTINUE;
}
/*
* Find length by adding up the underlying segments. The segments can be straights, curves or bezier.
*/
DIST_T BezierLength(coOrd pos[4],dynArr_t segs) {
DIST_T dd = 0.0;
if (segs.cnt == 0 ) return dd;
for (int i = 0;i<segs.cnt;i++) {
trkSeg_t t = DYNARR_N(trkSeg_t, segs, i);
if (t.type == SEG_CRVTRK || t.type == SEG_CRVLIN) {
dd += fabs(t.u.c.radius*D2R(t.u.c.a1));
} else if (t.type == SEG_BEZLIN || t.type == SEG_BEZTRK) {
dd +=BezierLength(t.u.b.pos,t.bezSegs);
} else if (t.type == SEG_STRLIN || t.type == SEG_STRTRK ) {
dd += FindDistance(t.u.l.pos[0],t.u.l.pos[1]);
}
}
return dd;
}
DIST_T BezierMinRadius(coOrd pos[4],dynArr_t segs) {
DIST_T r = 100000.0, rr;
if (segs.cnt == 0 ) return r;
for (int i = 0;i<segs.cnt;i++) {
trkSeg_t t = DYNARR_N(trkSeg_t, segs, i);
if (t.type == SEG_CRVTRK || t.type == SEG_CRVLIN) {
rr = fabs(t.u.c.radius);
} else if (t.type == SEG_BEZLIN || t.type == SEG_BEZTRK) {
rr = BezierMinRadius(t.u.b.pos, t.bezSegs);
} else rr = 100000.00;
if (rr<r) r = rr;
}
return r;
}
/*
* Create a Bezier Curve (Track or Line)
* Sequence is
* 1. Place 1st End (snapping if needed)
* 2.Drag out 1st Control Arm (in one direction if snapped)
* 3.Place 2nd End (again snapping)
* 4.Drag out 2nd Control Arm (constrained if snapped)
* 5 to n. Select and drag around points until done
* n+1. Confirm with enter or Cancel with Esc
*/
STATUS_T CmdBezCurve( wAction_t action, coOrd pos )
{
track_p t;
static int segCnt;
STATUS_T rc = C_CONTINUE;
long curveMode = 0;
long cmd;
if (action>>8) {
cmd = action>>8;
} else cmd = (long)commandContext;
Da.color = lineColor;
Da.width = (double)lineWidth/mainD.dpi;
Da.trackGauge = trackGauge;
switch (action&0xFF) {
case C_START:
Da.track = (cmd == bezCmdModifyTrack || cmd == bezCmdCreateTrack)?TRUE:FALSE;
Da.state = POS_1;
Da. selectPoint = -1;
for (int i=0;i<4;i++) {
Da.pos[i] = zero;
}
Da.trk[0] = Da.trk[1] = NULL;
//tempD.orig = mainD.orig;
DYNARR_RESET(trkSeg_t,Da.crvSegs_da);
Da.cp1Segs_da_cnt = 0;
Da.cp2Segs_da_cnt = 0;
InfoMessage( _("Place 1st end point of Bezier + Shift -> snap to %s end"), Da.track?"Unconnected Track":"Line" );
return C_CONTINUE;
case C_DOWN:
if ( Da.state == POS_1 || Da.state == POS_2) { //Set the first or third point
coOrd p = pos;
BOOL_T found = FALSE;
int end = Da.state==POS_1?0:1;
EPINX_T ep;
if (Da.track) {
if ((MyGetKeyState() & WKEY_SHIFT) != 0) { //Snap Track
if ((t = OnTrack(&p, FALSE, TRUE)) != NULL) {
ep = PickUnconnectedEndPointSilent(p, t);
if (ep != -1) {
Da.trk[end] = t;
Da.ep[end] = ep;
pos = GetTrkEndPos(t, ep);
found = TRUE;
}
}
if (!found) {
wBeep();
InfoMessage(_("Shift used, but no Unconnected Track End there"));
return C_CONTINUE;
}
}
} else { //Snap Bez Line to Lines
if ((MyGetKeyState() & WKEY_SHIFT) != 0) {
if ((t = OnTrack(&p,FALSE, FALSE)) != NULL) {
if (GetClosestEndPt(t,&p)) {
pos = p;
found = TRUE;
}
} else {
wBeep();
InfoMessage(_("Shift used, but no Line End there"));
return C_CONTINUE;
}
}
}
if (!found) SnapPos( &pos );
if (Da.state == POS_1) {
Da.pos[0] = pos;
Da.pos[1] = pos;
Da.state = CONTROL_ARM_1; //Draw the first control arm
Da.selectPoint = 1;
InfoMessage( _("Drag end of first Control Arm") );
Da.cp1Segs_da_cnt = createControlArm(Da.cp1Segs_da, Da.pos[0], Da.pos[1], Da.track,TRUE,Da.trk[1]!=NULL,1,wDrawColorBlack);
DrawBezCurve(Da.cp1Segs_da,Da.cp1Segs_da_cnt,NULL,0,NULL,0,drawColorBlack);
} else {
Da.pos[3] = pos; //2nd End Point
Da.pos[2] = pos; //2nd Ctl Point
Da.state = POINT_PICKED; // Drag out the second control arm
Da.selectPoint = 2;
InfoMessage( _("Drag end of second Control Arm") );
DrawBezCurve(Da.cp1Segs_da,Da.cp1Segs_da_cnt,NULL,0,NULL,0,drawColorBlack); //Wipe out initial Arm
Da.cp1Segs_da_cnt = createControlArm(Da.cp1Segs_da, Da.pos[0], Da.pos[1], Da.track,FALSE,Da.trk[0]!=NULL,-1,wDrawColorBlack);
Da.cp2Segs_da_cnt = createControlArm(Da.cp2Segs_da, Da.pos[3], Da.pos[2], Da.track,TRUE,Da.trk[1]!=NULL,1,wDrawColorBlack);
if (ConvertToArcs(Da.pos,&Da.crvSegs_da,Da.track,Da.color,Da.width)) Da.crvSegs_da_cnt = Da.crvSegs_da.cnt;
DrawTempBezier(Da.track);
}
return C_CONTINUE;
} else {
return AdjustBezCurve( action&0xFF, pos, Da.track, Da.color, Da.width, InfoMessage );
}
return C_CONTINUE;
case C_MOVE:
if (Da.state == POS_1) {
InfoMessage( _("Place 1st end point of Bezier + Shift -> snap to %s end"), Da.track?"Unconnected Track":"Line" );
return C_CONTINUE;
}
if (Da.state == POS_2) {
InfoMessage( _("Select other end of Bezier, +Shift -> snap to %s end"), Da.track?"Unconnected Track":"Line" );
}
if (Da.state == CONTROL_ARM_1 ) {
DrawBezCurve(Da.cp1Segs_da,Da.cp1Segs_da_cnt,NULL,0,NULL,0,drawColorBlack);
if (Da.trk[0]) {
EPINX_T ep = 0;
ANGLE_T angle1,angle2;
angle1 = NormalizeAngle(GetTrkEndAngle(Da.trk[0],Da.ep[0]));
angle2 = NormalizeAngle(FindAngle(pos, Da.pos[0])-angle1);
if (angle2 > 90.0 && angle2 < 270.0)
Translate( &pos, Da.pos[0], angle1, -FindDistance( Da.pos[0], pos )*cos(D2R(angle2)));
else pos = Da.pos[0];
} // Don't Snap control points
Da.pos[1] = pos;
Da.cp1Segs_da_cnt = createControlArm(Da.cp1Segs_da, Da.pos[0], Da.pos[1], Da.track, TRUE, Da.trk[0]!=NULL, 1, wDrawColorBlack);
DrawBezCurve(Da.cp1Segs_da,Da.cp1Segs_da_cnt,NULL,0,NULL,0,drawColorBlack);
} else {
return AdjustBezCurve( action&0xFF, pos, Da.track, Da.color, Da.width, InfoMessage );
}
return C_CONTINUE;
case C_UP:
if (Da.state == CONTROL_ARM_1) {
DrawBezCurve(Da.cp1Segs_da,Da.cp1Segs_da_cnt,NULL,0,NULL,0,drawColorBlack);
if (Da.trk[0]) {
EPINX_T ep = Da.ep[0];
ANGLE_T angle1,angle2;
angle1 = NormalizeAngle(GetTrkEndAngle(Da.trk[0],Da.ep[0]));
angle2 = NormalizeAngle(FindAngle(pos, Da.pos[0])-angle1);
if (angle2 > 90.0 && angle2 < 270.0)
Translate( &pos, Da.pos[0], angle1, -FindDistance( Da.pos[0], pos )*cos(D2R(angle2)));
else pos = Da.pos[0];
} // Don't Snap control points
Da.pos[1] = pos;
if (FindDistance(Da.pos[0],Da.pos[1]) <=minLength) {
InfoMessage( _("Control Arm 1 is too short, try again") );
Da.state = POS_1;
return C_CONTINUE;
}
Da.state = POS_2;
InfoMessage( _("Select other end of Bezier, +Shift -> snap to %s end"), Da.track?"Unconnected Track":"Line" );
Da.cp1Segs_da_cnt = createControlArm(Da.cp1Segs_da, Da.pos[0], Da.pos[1], Da.track, FALSE, Da.trk[0]!=NULL, -1, wDrawColorBlack);
DrawBezCurve(Da.cp1Segs_da,Da.cp1Segs_da_cnt,NULL,0,NULL,0,drawColorBlack);
return C_CONTINUE;
} else {
return AdjustBezCurve( action&0xFF, pos, Da.track, Da.color, Da.width, InfoMessage );
}
case C_TEXT:
if (Da.state != PICK_POINT || (action>>8) != ' ') //Space is same as Enter.
return C_CONTINUE;
/* no break */
case C_OK:
if (Da.state != PICK_POINT) return C_CONTINUE;
return AdjustBezCurve( C_OK, pos, Da.track, Da.color, Da.width, InfoMessage);
case C_REDRAW:
if ( Da.state != NONE ) {
DrawBezCurve(Da.cp1Segs_da,Da.cp1Segs_da_cnt,Da.cp2Segs_da,Da.cp2Segs_da_cnt,(trkSeg_t *)Da.crvSegs_da.ptr,Da.crvSegs_da.cnt, Da.color);
}
return C_CONTINUE;
case C_CANCEL:
if (Da.state != NONE) {
DrawBezCurve(Da.cp1Segs_da,Da.cp1Segs_da_cnt,Da.cp2Segs_da,Da.cp2Segs_da_cnt,(trkSeg_t *)Da.crvSegs_da.ptr,Da.crvSegs_da.cnt, Da.color);
Da.cp1Segs_da_cnt = 0;
Da.cp2Segs_da_cnt = 0;
Da.crvSegs_da_cnt = 0;
for (int i=0;i<2;i++) {
Da.trk[i] = NULL;
Da.ep[i] = -1;
}
if (Da.crvSegs_da.ptr) MyFree(Da.crvSegs_da.ptr);
Da.crvSegs_da.ptr = NULL;
Da.crvSegs_da.cnt = 0;
Da.crvSegs_da.max = 0;
}
Da.state = NONE;
return C_CONTINUE;
default:
return C_CONTINUE;
}
}
void UpdateParms(wDrawColor color,long width) {
DrawTempBezier(Da.track);
Da.color = lineColor;
Da.width = (double)lineWidth/mainD.dpi;
if (Da.crvSegs_da.cnt) {
ConvertToArcs(Da.pos,&Da.crvSegs_da,Da.track,Da.color,Da.width);
}
DrawTempBezier(Da.track);
}
#include "bitmaps/bezier.xpm"
#include "bitmaps/dbezier.xpm"
EXPORT void InitCmdBezier( wMenu_p menu )
{
}