+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <math.h>
+#include <string.h>
+#include <gtk/gtk.h>
+#include <libgnomecanvas/libgnomecanvas.h>
+
+#include "xournal.h"
+#include "xo-shapes.h"
+#include "xo-paint.h"
+
+typedef struct Inertia {
+ double mass, sx, sy, sxx, sxy, syy;
+} Inertia;
+
+typedef struct RecoSegment {
+ struct Item *item;
+ int startpt, endpt;
+ double xcenter, ycenter, angle, radius;
+ double x1, y1, x2, y2;
+ gboolean reversed;
+} RecoSegment;
+
+struct RecoSegment recognizer_queue[MAX_POLYGON_SIDES+1];
+int recognizer_queue_length;
+struct UndoItem *last_item_checker; // check if queue is stale
+
+void reset_recognizer(void)
+{
+ recognizer_queue_length = 0;
+ last_item_checker = NULL;
+}
+
+/* compute mass and moments of a stroke */
+
+void incr_inertia(double *pt, struct Inertia *s, int coef)
+{
+ double dm;
+ dm = coef*hypot(pt[2]-pt[0], pt[3]-pt[1]);
+ s->mass += dm;
+ s->sx += dm*pt[0];
+ s->sy += dm*pt[1];
+ s->sxx += dm*pt[0]*pt[0];
+ s->syy += dm*pt[1]*pt[1];
+ s->sxy += dm*pt[0]*pt[1];
+}
+
+void calc_inertia(double *pt, int start, int end, struct Inertia *s)
+{
+ int i;
+
+ s->mass = s->sx = s->sy = s->sxx = s->sxy = s->syy = 0.;
+ for (i=start, pt+=2*start; i<end; i++, pt+=2) incr_inertia(pt, s, 1);
+}
+
+/* compute normalized quantities */
+
+inline double center_x(struct Inertia s)
+{
+ return s.sx/s.mass;
+}
+
+inline double center_y(struct Inertia s)
+{
+ return s.sy/s.mass;
+}
+
+inline double I_xx(struct Inertia s)
+{
+ return (s.sxx - s.sx*s.sx/s.mass)/s.mass;
+}
+
+inline double I_xy(struct Inertia s)
+{
+ return (s.sxy - s.sx*s.sy/s.mass)/s.mass;
+}
+
+inline double I_yy(struct Inertia s)
+{
+ return (s.syy - s.sy*s.sy/s.mass)/s.mass;
+}
+
+inline double I_rad(struct Inertia s)
+{
+ return sqrt(I_xx(s)+I_yy(s));
+}
+
+inline double I_det(struct Inertia s)
+{
+ if (s.mass == 0.) return 0.;
+ double ixx = I_xx(s), iyy = I_yy(s), ixy = I_xy(s);
+ return 4*(ixx*iyy-ixy*ixy)/(ixx+iyy)/(ixx+iyy);
+}
+
+/* check if something is a polygonal line with at most nsides sides */
+
+int find_polygonal(double *pt, int start, int end, int nsides, int *breaks, struct Inertia *ss)
+{
+ struct Inertia s, s1, s2;
+ int k, i1, i2, n1, n2;
+ double det1, det2;
+
+ if (end == start) return 0; // no way
+ if (nsides <= 0) return 0;
+ if (end-start<5) nsides = 1; // too small for a polygon
+
+ // look for a linear piece that's big enough
+ for (k=0; k<nsides; k++) {
+ i1 = start + (k*(end-start))/nsides;
+ i2 = start + ((k+1)*(end-start))/nsides;
+ calc_inertia(pt, i1, i2, &s);
+ if (I_det(s) < LINE_MAX_DET) break;
+ }
+ if (k==nsides) return 0; // failed!
+
+ // grow the linear piece we found
+ while (1) {
+ if (i1>start) {
+ s1 = s;
+ incr_inertia(pt+2*(i1-1), &s1, 1);
+ det1 = I_det(s1);
+ }
+ else det1 = 1.;
+ if (i2<end) {
+ s2 = s;
+ incr_inertia(pt+2*i2, &s2, 1);
+ det2 = I_det(s2);
+ }
+ else det2 = 1.;
+ if (det1<det2 && det1<LINE_MAX_DET) { i1--; s=s1; }
+ else if (det2<det1 && det2<LINE_MAX_DET) { i2++; s=s2; }
+ else break;
+ }
+
+ if (i1>start) {
+ n1 = find_polygonal(pt, start, i1, (i2==end)?(nsides-1):(nsides-2), breaks, ss);
+ if (n1 == 0) return 0; // it doesn't work
+ }
+ else n1 = 0;
+
+ breaks[n1] = i1;
+ breaks[n1+1] = i2;
+ ss[n1] = s;
+
+ if (i2<end) {
+ n2 = find_polygonal(pt, i2, end, nsides-n1-1, breaks+n1+1, ss+n1+1);
+ if (n2 == 0) return 0;
+ }
+ else n2 = 0;
+
+ return n1+n2+1;
+}
+
+/* improve on the polygon found by find_polygonal() */
+
+void optimize_polygonal(double *pt, int nsides, int *breaks, struct Inertia *ss)
+{
+ int i;
+ double cost, newcost;
+ struct Inertia s1, s2;
+ gboolean improved;
+
+ for (i=1; i<nsides; i++) {
+ // optimize break between sides i and i+1
+ cost = I_det(ss[i-1])*I_det(ss[i-1])+I_det(ss[i])*I_det(ss[i]);
+ s1 = ss[i-1]; s2 = ss[i];
+ improved = FALSE;
+ while (breaks[i]>breaks[i-1]+1) {
+ // try moving the break to the left
+ incr_inertia(pt+2*(breaks[i]-1), &s1, -1);
+ incr_inertia(pt+2*(breaks[i]-1), &s2, 1);
+ newcost = I_det(s1)*I_det(s1)+I_det(s2)*I_det(s2);
+ if (newcost >= cost) break;
+ improved = TRUE;
+ cost = newcost;
+ breaks[i]--;
+ ss[i-1] = s1;
+ ss[i] = s2;
+ }
+ if (improved) continue;
+ s1 = ss[i-1]; s2 = ss[i];
+ while (breaks[i]<breaks[i+1]-1) {
+ // try moving the break to the right
+ incr_inertia(pt+2*breaks[i], &s1, 1);
+ incr_inertia(pt+2*breaks[i], &s2, -1);
+ newcost = I_det(s1)*I_det(s1)+I_det(s2)*I_det(s2);
+ if (newcost >= cost) break;
+ cost = newcost;
+ breaks[i]++;
+ ss[i-1] = s1;
+ ss[i] = s2;
+ }
+ }
+}
+
+/* find the geometry of a recognized segment */
+
+void get_segment_geometry(double *pt, int start, int end, struct Inertia *s, struct RecoSegment *r)
+{
+ double a, b, c, lmin, lmax, l;
+ int i;
+
+ r->xcenter = center_x(*s);
+ r->ycenter = center_y(*s);
+ a = I_xx(*s); b = I_xy(*s); c = I_yy(*s);
+ /* max angle for inertia quadratic form solves: tan(2t) = 2b/(a-c) */
+ r->angle = atan2(2*b, a-c)/2;
+ r->radius = sqrt(3*(a+c));
+
+ lmin = lmax = 0.;
+ for (i=start, pt+=2*start; i<=end; i++, pt+=2) {
+ l = (pt[0]-r->xcenter)*cos(r->angle)+(pt[1]-r->ycenter)*sin(r->angle);
+ if (l<lmin) lmin = l;
+ if (l>lmax) lmax = l;
+ }
+ r->x1 = r->xcenter + lmin*cos(r->angle);
+ r->y1 = r->ycenter + lmin*sin(r->angle);
+ r->x2 = r->xcenter + lmax*cos(r->angle);
+ r->y2 = r->ycenter + lmax*sin(r->angle);
+}
+
+/* test if we have a circle; inertia has been precomputed by caller */
+
+double score_circle(double *pt, int start, int end, struct Inertia *s)
+{
+ double sum, x0, y0, r0, dm, deltar;
+ int i;
+
+ if (s->mass == 0.) return 0;
+ sum = 0.;
+ x0 = center_x(*s); y0 = center_y(*s); r0 = I_rad(*s);
+ for (i=start, pt+=2*start; i<end; i++, pt+=2) {
+ dm = hypot(pt[2]-pt[0], pt[3]-pt[1]);
+ deltar = hypot(pt[0]-x0, pt[1]-y0) - r0;
+ sum += dm * fabs(deltar);
+ }
+ return sum/(s->mass*r0);
+}
+
+/* replace strokes by various shapes */
+
+void make_circle_shape(double x0, double y0, double r)
+{
+ int npts, i;
+ struct Item *item;
+ struct UndoErasureData *erasure;
+
+ npts = (int)(2*r);
+ if (npts<12) npts = 12; // min. number of points
+ realloc_cur_path(npts+1);
+ ui.cur_path.num_points = npts+1;
+ for (i=0;i<=npts; i++) {
+ ui.cur_path.coords[2*i] = x0 + r*cos((2*M_PI*i)/npts);
+ ui.cur_path.coords[2*i+1] = y0 + r*sin((2*M_PI*i)/npts);
+ }
+}
+
+void calc_edge_isect(struct RecoSegment *r1, struct RecoSegment *r2, double *pt)
+{
+ double t;
+ t = (r2->xcenter - r1->xcenter) * sin(r2->angle) -
+ (r2->ycenter - r1->ycenter) * cos(r2->angle);
+ t /= sin(r2->angle-r1->angle);
+ pt[0] = r1->xcenter + t*cos(r1->angle);
+ pt[1] = r1->ycenter + t*sin(r1->angle);
+}
+
+void remove_recognized_strokes(struct RecoSegment *rs, int num_old_items)
+{
+ struct Item *old_item;
+ int i, shift;
+ struct UndoErasureData *erasure;
+
+ old_item = NULL;
+ prepare_new_undo();
+ undo->type = ITEM_RECOGNIZER;
+ undo->layer = ui.cur_layer;
+ undo->erasurelist = NULL;
+ shift = 0;
+
+ for (i=0; i<num_old_items; i++) {
+ if (rs[i].item == old_item) continue; // already done
+ old_item = rs[i].item;
+ erasure = g_new(struct UndoErasureData, 1);
+ erasure->item = old_item;
+ erasure->npos = g_list_index(ui.cur_layer->items, old_item) + (shift++);
+ erasure->nrepl = 0;
+ erasure->replacement_items = NULL;
+ undo->erasurelist = g_list_append(undo->erasurelist, erasure);
+ if (old_item->canvas_item != NULL)
+ gtk_object_destroy(GTK_OBJECT(old_item->canvas_item));
+ ui.cur_layer->items = g_list_remove(ui.cur_layer->items, old_item);
+ ui.cur_layer->nitems--;
+ }
+}
+
+struct Item *insert_recognized_curpath(void)
+{
+ struct Item *item;
+ int i;
+ struct UndoErasureData *erasure;
+
+ erasure = (struct UndoErasureData *)(undo->erasurelist->data);
+ item = g_new(struct Item, 1);
+ item->type = ITEM_STROKE;
+ g_memmove(&(item->brush), &(erasure->item->brush), sizeof(struct Brush));
+ item->brush.variable_width = FALSE;
+ subdivide_cur_path();
+ item->path = gnome_canvas_points_new(ui.cur_path.num_points);
+ g_memmove(item->path->coords, ui.cur_path.coords, 2*ui.cur_path.num_points*sizeof(double));
+ item->widths = NULL;
+ update_item_bbox(item);
+ ui.cur_path.num_points = 0;
+
+ erasure->nrepl++;
+ erasure->replacement_items = g_list_append(erasure->replacement_items, item);
+ ui.cur_layer->items = g_list_append(ui.cur_layer->items, item);
+ ui.cur_layer->nitems++;
+ make_canvas_item_one(ui.cur_layer->group, item);
+ return item;
+}
+
+
+/* test if segments form standard shapes */
+
+gboolean try_rectangle(void)
+{
+ struct RecoSegment *rs, *r1, *r2;
+ int i;
+ double dist, avg_angle;
+
+ // first, we need whole strokes to combine to 4 segments...
+ if (recognizer_queue_length<4) return FALSE;
+ rs = recognizer_queue + recognizer_queue_length - 4;
+ if (rs->startpt!=0) return FALSE;
+
+ // check edges make angles ~= Pi/2 and vertices roughly match
+ avg_angle = 0.;
+ for (i=0; i<=3; i++) {
+ r1 = rs+i; r2 = rs+(i+1)%4;
+ if (fabs(fabs(r1->angle-r2->angle)-M_PI/2) > RECTANGLE_ANGLE_TOLERANCE)
+ return FALSE;
+ avg_angle += r1->angle;
+ if (r2->angle > r1->angle) avg_angle += (i+1)*M_PI/2;
+ else avg_angle -= (i+1)*M_PI/2;
+ // test if r1 points away from r2 rather than towards it
+ r1->reversed = ((r1->x2-r1->x1)*(r2->xcenter-r1->xcenter)+
+ (r1->y2-r1->y1)*(r2->ycenter-r1->ycenter)) < 0;
+ }
+ for (i=0; i<=3; i++) {
+ r1 = rs+i; r2 = rs+(i+1)%4;
+ dist = hypot((r1->reversed?r1->x1:r1->x2) - (r2->reversed?r2->x2:r2->x1),
+ (r1->reversed?r1->y1:r1->y2) - (r2->reversed?r2->y2:r2->y1));
+ if (dist > RECTANGLE_LINEAR_TOLERANCE*(r1->radius+r2->radius)) return FALSE;
+ }
+
+ // make a rectangle of the correct size and slope
+ avg_angle = avg_angle/4;
+ if (fabs(avg_angle)<SLANT_TOLERANCE) avg_angle = 0.;
+ if (fabs(avg_angle)>M_PI/2-SLANT_TOLERANCE) avg_angle = M_PI/2;
+ realloc_cur_path(5);
+ ui.cur_path.num_points = 5;
+ for (i=0; i<=3; i++) rs[i].angle = avg_angle+i*M_PI/2;
+ for (i=0; i<=3; i++) calc_edge_isect(rs+i, rs+(i+1)%4, ui.cur_path.coords+2*i+2);
+ ui.cur_path.coords[0] = ui.cur_path.coords[8];
+ ui.cur_path.coords[1] = ui.cur_path.coords[9];
+
+ remove_recognized_strokes(rs, 4);
+ insert_recognized_curpath();
+ return TRUE;
+}
+
+gboolean try_arrow(void)
+{
+ struct RecoSegment *rs;
+ int i, j;
+ double alpha[3], dist, pt[2], tmp, delta;
+ double x1, y1, x2, y2, angle;
+ gboolean rev[3];
+
+ // first, we need whole strokes to combine to nsides segments...
+ if (recognizer_queue_length<3) return FALSE;
+ rs = recognizer_queue + recognizer_queue_length - 3;
+ if (rs->startpt!=0) return FALSE;
+
+ // check arrow head not too big, and orient main segment
+ for (i=1; i<=2; i++) {
+ if (rs[i].radius > ARROW_MAXSIZE*rs[0].radius) return FALSE;
+ rev[i] = (hypot(rs[i].xcenter-rs->x1, rs[i].ycenter-rs->y1) <
+ hypot(rs[i].xcenter-rs->x2, rs[i].ycenter-rs->y2));
+ }
+ if (rev[1]!=rev[2]) return FALSE;
+ if (rev[1]) {
+ x1 = rs->x2; y1 = rs->y2; x2 = rs->x1; y2 = rs->y1;
+ angle = rs->angle + M_PI;
+ }
+ else {
+ x1 = rs->x1; y1 = rs->y1; x2 = rs->x2; y2 = rs->y2;
+ angle = rs->angle;
+ }
+
+ // check arrow head not too big, and angles roughly ok
+ for (i=1; i<=2; i++) {
+ rs[i].reversed = FALSE;
+ alpha[i] = rs[i].angle - angle;
+ while (alpha[i]<-M_PI/2) { alpha[i]+=M_PI; rs[i].reversed = !rs[i].reversed; }
+ while (alpha[i]>M_PI/2) { alpha[i]-=M_PI; rs[i].reversed = !rs[i].reversed; }
+#ifdef RECOGNIZER_DEBUG
+ printf("arrow: alpha[%d] = %.1f degrees\n", i, alpha[i]*180/M_PI);
+#endif
+ if (fabs(alpha[i])<ARROW_ANGLE_MIN || fabs(alpha[i])>ARROW_ANGLE_MAX) return FALSE;
+ }
+
+ // check arrow head segments are roughly symmetric
+ if (alpha[1]*alpha[2]>0 || fabs(alpha[1]+alpha[2]) > ARROW_ASYMMETRY_MAX_ANGLE) return FALSE;
+ if (rs[1].radius/rs[2].radius > 1+ARROW_ASYMMETRY_MAX_LINEAR) return FALSE;
+ if (rs[2].radius/rs[1].radius > 1+ARROW_ASYMMETRY_MAX_LINEAR) return FALSE;
+
+ // check vertices roughly match
+ calc_edge_isect(rs+1, rs+2, pt);
+ for (j=1; j<=2; j++) {
+ dist = hypot(pt[0]-(rs[j].reversed?rs[j].x1:rs[j].x2),
+ pt[1]-(rs[j].reversed?rs[j].y1:rs[j].y2));
+#ifdef RECOGNIZER_DEBUG
+ printf("linear tolerance: tip[%d] = %.2f\n", j, dist/rs[j].radius);
+#endif
+ if (dist>ARROW_TIP_LINEAR_TOLERANCE*rs[j].radius) return FALSE;
+ }
+ dist = (pt[0]-x2)*sin(angle)-(pt[1]-y2)*cos(angle);
+ dist /= rs[1].radius + rs[2].radius;
+#ifdef RECOGNIZER_DEBUG
+ printf("sideways gap tolerance = %.2f\n", dist);
+#endif
+ if (fabs(dist)>ARROW_SIDEWAYS_GAP_TOLERANCE) return FALSE;
+ dist = (pt[0]-x2)*cos(angle)+(pt[1]-y2)*sin(angle);
+ dist /= rs[1].radius + rs[2].radius;
+#ifdef RECOGNIZER_DEBUG
+ printf("main linear gap = %.2f\n", dist);
+#endif
+ if (dist<ARROW_MAIN_LINEAR_GAP_MIN || dist>ARROW_MAIN_LINEAR_GAP_MAX) return FALSE;
+
+ // make an arrow of the correct size and slope
+ if (fabs(rs->angle)<SLANT_TOLERANCE) { // nearly horizontal
+ angle = angle - rs->angle;
+ y1 = y2 = rs->ycenter;
+ }
+ if (rs->angle>M_PI/2-SLANT_TOLERANCE) { // nearly vertical
+ angle = angle - (rs->angle-M_PI/2);
+ x1 = x2 = rs->xcenter;
+ }
+ if (rs->angle<-M_PI/2+SLANT_TOLERANCE) { // nearly vertical
+ angle = angle - (rs->angle+M_PI/2);
+ x1 = x2 = rs->xcenter;
+ }
+ delta = fabs(alpha[1]-alpha[2])/2;
+ dist = (hypot(rs[1].x1-rs[1].x2, rs[1].y1-rs[1].y2) +
+ hypot(rs[2].x1-rs[2].x2, rs[2].y1-rs[2].y2))/2;
+
+ realloc_cur_path(2);
+ ui.cur_path.num_points = 2;
+ ui.cur_path.coords[0] = x1; ui.cur_path.coords[1] = y1;
+ ui.cur_path.coords[2] = x2; ui.cur_path.coords[3] = y2;
+ remove_recognized_strokes(rs, 3);
+ insert_recognized_curpath();
+
+ realloc_cur_path(3);
+ ui.cur_path.num_points = 3;
+ ui.cur_path.coords[0] = x2 - dist*cos(angle+delta);
+ ui.cur_path.coords[1] = y2 - dist*sin(angle+delta);
+ ui.cur_path.coords[2] = x2;
+ ui.cur_path.coords[3] = y2;
+ ui.cur_path.coords[4] = x2 - dist*cos(angle-delta);
+ ui.cur_path.coords[5] = y2 - dist*sin(angle-delta);
+ insert_recognized_curpath();
+
+ return TRUE;
+}
+
+gboolean try_closed_polygon(int nsides)
+{
+ struct RecoSegment *rs, *r1, *r2;
+ int i;
+ double dist, pt[2];
+
+ // first, we need whole strokes to combine to nsides segments...
+ if (recognizer_queue_length<nsides) return FALSE;
+ rs = recognizer_queue + recognizer_queue_length - nsides;
+ if (rs->startpt!=0) return FALSE;
+
+ // check vertices roughly match
+ for (i=0; i<nsides; i++) {
+ r1 = rs+i; r2 = rs+(i+1)%nsides;
+ // test if r1 points away from r2 rather than towards it
+ calc_edge_isect(r1, r2, pt);
+ r1->reversed = (hypot(pt[0]-r1->x1,pt[1]-r1->y1) < hypot(pt[0]-r1->x2,pt[1]-r1->y2));
+ }
+ for (i=0; i<nsides; i++) {
+ r1 = rs+i; r2 = rs+(i+1)%nsides;
+ calc_edge_isect(r1, r2, pt);
+ dist = hypot((r1->reversed?r1->x1:r1->x2)-pt[0],(r1->reversed?r1->y1:r1->y2)-pt[1])
+ + hypot((r2->reversed?r2->x2:r2->x1)-pt[0],(r2->reversed?r2->y2:r2->y1)-pt[1]);
+ if (dist > POLYGON_LINEAR_TOLERANCE*(r1->radius+r2->radius)) return FALSE;
+ }
+
+ // make a polygon of the correct size and slope
+ realloc_cur_path(nsides+1);
+ ui.cur_path.num_points = nsides+1;
+ for (i=0; i<nsides; i++)
+ calc_edge_isect(rs+i, rs+(i+1)%nsides, ui.cur_path.coords+2*i+2);
+ ui.cur_path.coords[0] = ui.cur_path.coords[2*nsides];
+ ui.cur_path.coords[1] = ui.cur_path.coords[2*nsides+1];
+
+ remove_recognized_strokes(rs, nsides);
+ insert_recognized_curpath();
+ return TRUE;
+}
+
+/* the main pattern recognition function, called after finalize_stroke() */
+void recognize_patterns(void)
+{
+ struct Item *it;
+ struct Inertia s, ss[4];
+ struct RecoSegment *rs;
+ int n, i;
+ int brk[5];
+ double score;
+
+ if (!undo || undo->type!=ITEM_STROKE) return;
+ if (undo->next != last_item_checker) reset_recognizer(); // reset queue
+ if (last_item_checker!=NULL && ui.cur_layer != last_item_checker->layer) reset_recognizer();
+
+ it = undo->item;
+ calc_inertia(it->path->coords, 0, it->path->num_points-1, &s);
+#ifdef RECOGNIZER_DEBUG
+ printf("Mass=%.0f, Center=(%.1f,%.1f), I=(%.0f,%.0f, %.0f), "
+ "Rad=%.2f, Det=%.4f \n",
+ s.mass, center_x(s), center_y(s), I_xx(s), I_yy(s), I_xy(s), I_rad(s), I_det(s));
+#endif
+
+ // first see if it's a polygon
+ n = find_polygonal(it->path->coords, 0, it->path->num_points-1, MAX_POLYGON_SIDES, brk, ss);
+ if (n>0) {
+ optimize_polygonal(it->path->coords, n, brk, ss);
+#ifdef RECOGNIZER_DEBUG
+ printf("Polygon, %d edges: ", n);
+ for (i=0; i<n; i++)
+ printf("%d-%d (M=%.0f, det=%.4f) ", brk[i], brk[i+1], ss[i].mass, I_det(ss[i]));
+ printf("\n");
+#endif
+ /* update recognizer segment queue (most recent at end) */
+ while (n+recognizer_queue_length > MAX_POLYGON_SIDES) {
+ // remove oldest polygonal stroke
+ i=1;
+ while (i<recognizer_queue_length && recognizer_queue[i].startpt!=0) i++;
+ recognizer_queue_length-=i;
+ g_memmove(recognizer_queue, recognizer_queue+i,
+ recognizer_queue_length * sizeof(struct RecoSegment));
+ }
+#ifdef RECOGNIZER_DEBUG
+ printf("Queue now has %d + %d edges\n", recognizer_queue_length, n);
+#endif
+ rs = recognizer_queue + recognizer_queue_length;
+ recognizer_queue_length += n;
+ for (i=0; i<n; i++) {
+ rs[i].item = it;
+ rs[i].startpt = brk[i];
+ rs[i].endpt = brk[i+1];
+ get_segment_geometry(it->path->coords, brk[i], brk[i+1], ss+i, rs+i);
+ }
+ if (try_rectangle()) { reset_recognizer(); return; }
+ if (try_arrow()) { reset_recognizer(); return; }
+ if (try_closed_polygon(3)) { reset_recognizer(); return; }
+ if (try_closed_polygon(4)) { reset_recognizer(); return; }
+ if (n==1) { // current stroke is a line
+ if (fabs(rs->angle)<SLANT_TOLERANCE) { // nearly horizontal
+ rs->angle = 0.;
+ rs->y1 = rs->y2 = rs->ycenter;
+ }
+ if (fabs(rs->angle)>M_PI/2-SLANT_TOLERANCE) { // nearly vertical
+ rs->angle = (rs->angle>0)?(M_PI/2):(-M_PI/2);
+ rs->x1 = rs->x2 = rs->xcenter;
+ }
+ realloc_cur_path(2);
+ ui.cur_path.num_points = 2;
+ ui.cur_path.coords[0] = rs->x1;
+ ui.cur_path.coords[1] = rs->y1;
+ ui.cur_path.coords[2] = rs->x2;
+ ui.cur_path.coords[3] = rs->y2;
+ remove_recognized_strokes(rs, 1);
+ rs->item = insert_recognized_curpath();
+ }
+ last_item_checker = undo;
+ return;
+ }
+
+ // not a polygon: maybe a circle ?
+ reset_recognizer();
+ if (I_det(s)>CIRCLE_MIN_DET) {
+ score = score_circle(it->path->coords, 0, it->path->num_points-1, &s);
+#ifdef RECOGNIZER_DEBUG
+ printf("Circle score: %.2f\n", score);
+#endif
+ if (score < CIRCLE_MAX_SCORE) {
+ make_circle_shape(center_x(s), center_y(s), I_rad(s));
+ recognizer_queue[0].item = it;
+ remove_recognized_strokes(recognizer_queue, 1);
+ insert_recognized_curpath();
+ }
+ }
+}
+