/* Part of XPCE --- The SWI-Prolog GUI toolkit Author: Jan Wielemaker and Anjo Anjewierden E-mail: jan@swi.psy.uva.nl WWW: http://www.swi.psy.uva.nl/projects/xpce/ Copyright (c) 2000-2011, University of Amsterdam All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include #include #define MAXPTS 100 /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Implementation of Quadratic Bezier Curves. Using algorithm description from: http://graphics.cs.ucdavis.edu/CAGDNotes/Divide-and-Conquer-Bezier-Curve/Divide-and-Conquer-Bezier-Curve.html Cubic (using 4 control-points) are described in: http://muldoon.cipic.ucdavis.edu/CAGDNotes/Cubic-Bezier-Curves/Cubic-Bezier-Curves.html - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ static status initialiseBezier(Bezier b, Point start, Point end, Point c1, Point c2) { initialiseGraphical(b, ZERO, ZERO, ZERO, ZERO); if ( isDefault(c2) ) c2 = NIL; assign(b, start, start); assign(b, end, end); assign(b, control1, c1); assign(b, control2, c2); return requestComputeGraphical(b, DEFAULT); } /******************************* * ARROWS * *******************************/ status adjustFirstArrowBezier(Bezier b) { if ( notNil(b->first_arrow) ) { Any av[4]; av[0] = b->start->x; av[1] = b->start->y; av[2] = b->control1->x; av[3] = b->control1->y; if ( qadSendv(b->first_arrow, NAME_points, 4, av) ) { assign(b->first_arrow, displayed, ON); return ComputeGraphical(b->first_arrow); } } fail; } status adjustSecondArrowBezier(Bezier b) { if ( notNil(b->second_arrow) ) { Any av[4]; av[0] = b->end->x; av[1] = b->end->y; if ( notNil(b->control2) ) { av[2] = b->control2->x; av[3] = b->control2->y; } else { av[2] = b->control1->x; av[3] = b->control1->y; } if ( qadSendv(b->second_arrow, NAME_points, 4, av) ) { assign(b->second_arrow, displayed, ON); return ComputeGraphical(b->second_arrow); } } fail; } /******************************* * COMPUTING * *******************************/ static void shiftpts(IPoint pts, int to, int shift) { DEBUG(NAME_bezier, Cprintf("Shift to %d\n", to)); to--; for(; to>=shift; to--) pts[to] = pts[to-shift]; } #define mkmid(p, p1, p2) \ { p.x = (p1.x + p2.x + 1)/2; \ p.y = (p1.y + p2.y + 1)/2; \ } static int splitQuadratic(IPoint pts, int i, int *n) { ipoint m; int md = 1; pts += i; mkmid(m, pts[0], pts[2]); if ( abs(m.x-pts[1].x) > md || abs(m.y-pts[1].y) > md ) { ipoint p1; p1 = pts[1]; *n = *n + 2; shiftpts(pts, *n-i, 2); mkmid(pts[1], pts[0], p1); mkmid(pts[3], p1, pts[4]); mkmid(pts[2], pts[1], pts[3]); return TRUE; } return FALSE; } static int splitCubic(IPoint pts, int i, int *n) { pts += i; if ( distanceLineToPoint(pts[0].x, pts[0].y, pts[3].x, pts[3].y, pts[1].x, pts[1].y, TRUE) > 1 || distanceLineToPoint(pts[0].x, pts[0].y, pts[3].x, pts[3].y, pts[2].x, pts[2].y, TRUE) > 1 ) { ipoint p1, p2, p12; p1 = pts[1]; p2 = pts[2]; *n = *n + 3; shiftpts(pts, *n-i, 3); mkmid(p12, p1, p2); mkmid(pts[1], pts[0], p1); mkmid(pts[5], p2, pts[6]); mkmid(pts[2], pts[1], p12); mkmid(pts[4], pts[5], p12); mkmid(pts[3], pts[2], pts[4]); return TRUE; } return FALSE; } /* static void printPts(IPoint pts, int n) { int i; for(i=0; ix = valInt(b->start->x); p->y = valInt(b->start->y); p++; p->x = valInt(b->control1->x); p->y = valInt(b->control1->y); p++; if ( notNil(b->control2) ) { p->x = valInt(b->control2->x); p->y = valInt(b->control2->y); p++; } p->x = valInt(b->end->x); p->y = valInt(b->end->y); p++; npts = p-pts; if ( notNil(b->control2) ) { for(i=0; i <= npts-3; i += 3) { if ( npts >= mxpts-3 ) break; while(splitCubic(pts, i, &npts)) ; } } else { for(i=0; i <= npts-3; i += 2) { if ( npts >= mxpts-2 ) break; while(splitQuadratic(pts, i, &npts)) ; } } *mx = npts; } typedef struct reg { int minx, miny, maxx, maxy; } reg; static void include_in_reg(reg *r, Point pt) { int px = valInt(pt->x); int py = valInt(pt->y); r->minx = min(r->minx, px); r->maxx = max(r->maxx, px); r->miny = min(r->miny, py); r->maxy = max(r->maxy, py); } static status computeBoundingBoxBezier(Bezier b) { reg r; r.minx = 1000000; r.miny = 1000000; r.maxx = -1000000; r.maxy = -10000000; if ( b->selected == ON ) { int mw=5, mh=5; include_in_reg(&r, b->start); include_in_reg(&r, b->end); include_in_reg(&r, b->control1); if ( notNil(b->control2) ) include_in_reg(&r, b->control2); r.minx -= (mw+1)/2; r.maxx += (mw+1)/2; r.miny -= (mh+1)/2; r.maxy += (mh+1)/2; } else { ipoint ptsbuf[MAXPTS]; IPoint pts = ptsbuf; int npts = MAXPTS; int i; compute_points_bezier(b, pts, &npts); for(i=0; i r.maxx ) r.maxx = pts[0].x; if ( pts[0].y < r.miny ) r.miny = pts[0].y; if ( pts[0].y > r.maxy ) r.maxy = pts[0].y; } } if ( r.maxx >= r.minx && r.maxy >= r.miny ) { int pens = valInt(b->pen) / 2; int pena = (valInt(b->pen) % 2 == 0 ? pens : pens + 1); r.minx -= pens; r.maxx += pena; r.miny -= pens; r.maxy += pena; assign(b->area, x, toInt(r.minx)); assign(b->area, y, toInt(r.miny)); assign(b->area, w, toInt(r.maxx - r.minx)); assign(b->area, h, toInt(r.maxy - r.miny)); } else clearArea(b->area); if ( adjustFirstArrowBezier(b) ) unionNormalisedArea(b->area, b->first_arrow->area); if ( adjustSecondArrowBezier(b) ) unionNormalisedArea(b->area, b->second_arrow->area); succeed; } static status computeBezier(Bezier b) { if ( notNil(b->request_compute) ) { CHANGING_GRAPHICAL(b, { computeBoundingBoxBezier(b); changedEntireImageGraphical(b); }); assign(b, request_compute, NIL); } succeed; } /******************************* * REDRAW * *******************************/ static status RedrawAreaBezier(Bezier b, Area a) { int x, y, w, h; ipoint pts[MAXPTS]; int npts = MAXPTS; initialiseDeviceGraphical(b, &x, &y, &w, &h); r_thickness(valInt(b->pen)); r_dash(b->texture); compute_points_bezier(b, pts, &npts); r_polygon(pts, npts, FALSE); if ( adjustFirstArrowBezier(b) ) RedrawArea(b->first_arrow, a); if ( adjustSecondArrowBezier(b) ) RedrawArea(b->second_arrow, a); return RedrawAreaGraphical(b, a); } static void drawControlPt(Point pt) { int bx = valInt(pt->x); int by = valInt(pt->y); r_complement(bx-2, by-2, 5, 5); } static void pt_line(Point p1, Point p2) { r_line(valInt(p1->x), valInt(p1->y), valInt(p2->x), valInt(p2->y)); } static status paintSelectedBezier(Bezier b) { PceWindow sw = getWindowGraphical((Graphical) b); if ( sw && sw->selection_feedback == (Any) NAME_handles ) { int x, y, w, h; initialiseDeviceGraphical(b, &x, &y, &w, &h); drawControlPt(b->start); drawControlPt(b->control1); if ( notNil(b->control2) ) drawControlPt(b->control2); drawControlPt(b->end); if ( 1 ) /* draw lines */ { r_dash(NAME_dotted); r_thickness(1); pt_line(b->start, b->control1); if ( notNil(b->control2) ) { pt_line(b->control1, b->control2); pt_line(b->control2, b->end); } else pt_line(b->control1, b->end); } succeed; } else return paintSelectedGraphical((Graphical)b); } /******************************* * PROPERTIES * *******************************/ static status startBezier(Bezier b, Point pt) { return assignGraphical(b, NAME_start, pt); } static status control1Bezier(Bezier b, Point pt) { return assignGraphical(b, NAME_control1, pt); } static status control2Bezier(Bezier b, Point pt) { return assignGraphical(b, NAME_control2, pt); } static status endBezier(Bezier b, Point pt) { return assignGraphical(b, NAME_end, pt); } static status pointsBezier(Bezier b, Int sx, Int sy, Int ex, Int ey) { assign(b->start, x, sx); assign(b->start, y, sy); assign(b->end, x, ex); assign(b->end, y, ey); requestComputeGraphical(b, DEFAULT); CHANGING_GRAPHICAL(b, { ComputeGraphical(b); changedEntireImageGraphical(b); }); succeed; } static status selectedBezier(Bezier b, BoolObj val) { return assignGraphical(b, NAME_selected, val); } /******************************* * PATH INTEGRATION * *******************************/ static status setPointBezier(Bezier b, Point pt, Int x, Int y) { setPoint(pt, x, y); return requestComputeGraphical(b, DEFAULT); } static void closerPoint(Point pt, Point pos, int *best, Point *r) { int d = valInt(getDistancePoint(pt, pos)); if ( d < *best ) { *best = d; *r = pt; } } static Point getPointBezier(Bezier b, Point pos, Int dist) { Point rval = NIL; int bestd = 0; /* make gcc happy */ if ( instanceOfObject(pos, ClassEvent) && notNil(b->device) ) pos = getPositionEvent((EventObj) pos, (Graphical) b->device); if ( isDefault(dist) ) dist = toInt(10); /* TBD */ bestd = valInt(getDistancePoint(b->start, pos)); rval = b->start; closerPoint(b->end, pos, &bestd, &rval); closerPoint(b->control1, pos, &bestd, &rval); if ( notNil(b->control2) ) closerPoint(b->control2, pos, &bestd, &rval); if ( notNil(rval) && bestd < valInt(dist) ) answer(rval); fail; } /******************************* * MOVING * *******************************/ static status geometryBezier(Bezier b, Int x, Int y, Int w, Int h) { if ( notDefault(x) || notDefault(y) ) { Int dx, dy; ComputeGraphical(b); if ( notDefault(x) ) dx = sub(x, b->area->x); else dx = ZERO; if ( notDefault(y) ) dy = sub(y, b->area->y); else dy = ZERO; if ( dx != ZERO || dy != ZERO ) { offsetPoint(b->start, dx, dy); offsetPoint(b->end, dx, dy); offsetPoint(b->control1, dx, dy); if ( notNil(b->control2) ) offsetPoint(b->control2, dx, dy); CHANGING_GRAPHICAL(b, { assign(b->area, x, add(b->area->x, dx)); assign(b->area, y, add(b->area->y, dy)); }); } } succeed; } /******************************* * CLASS DECLARATION * *******************************/ /* Type declarations */ static char *T_initialise[] = { "start=point", "end=point", "control1=point", "control2=[point]*" }; static char *T_points[] = { "start_x=int", "start_y=int", "end_x=int", "end_y=int" }; static char *T_geometry[] = { "x=[int]", "y=[int]", "width=[int]", "height=[int]" }; static char *T_setPoint[] = { "point=point", "x=[int]", "y=[int]" }; static char *T_point[] = { "near=point|event", "max_distance=[int]" }; /* Instance Variables */ static vardecl var_bezier[] = { SV(NAME_start, "point", IV_GET|IV_STORE, startBezier, NAME_tip, "Start point of Bezier curve"), SV(NAME_end, "point", IV_GET|IV_STORE, endBezier, NAME_tip, "End point of Bezier curve"), SV(NAME_control1, "point", IV_GET|IV_STORE, control1Bezier, NAME_appearance, "1st Control-point of the Bezier curve"), SV(NAME_control2, "point*", IV_GET|IV_STORE, control2Bezier, NAME_appearance, "2nd Control-point of the Bezier curve") }; /* Send Methods */ static senddecl send_bezier[] = { SM(NAME_initialise, 4, T_initialise, initialiseBezier, DEFAULT, "Create bezier from start, control and end"), SM(NAME_compute, 0, NULL, computeBezier, DEFAULT, "Recompute area"), SM(NAME_geometry, 4, T_geometry, geometryBezier, DEFAULT, "Move the Bezier curve"), SM(NAME_paintSelected, 0, NULL, paintSelectedBezier, NAME_appearance, "Paint inverted drops on control-points"), SM(NAME_points, 4, T_points, pointsBezier, NAME_tip, "Set start- and end-point"), SM(NAME_setPoint, 3, T_setPoint, setPointBezier, NAME_points, "Move (member) point to (X, Y)"), SM(NAME_selected, 1, "bool", selectedBezier, NAME_selection, "If @on, I'm selected"), SM(NAME_DrawPostScript, 1, "{head,body}", drawPostScriptBezier, NAME_postscript, "Create PostScript") }; /* Get Methods */ static getdecl get_bezier[] = { GM(NAME_point, 2, "point", T_point, getPointBezier, NAME_event, "Find closest point"), }; /* Resources */ #define rc_bezier NULL /* static classvardecl rc_bezier[] = { }; */ /* Class Declaration */ static Name bezier_termnames[] = { NAME_width, NAME_height }; ClassDecl(bezier_decls, var_bezier, send_bezier, get_bezier, rc_bezier, 2, bezier_termnames, "$Rev$"); status makeClassBezier(Class class) { declareClass(class, &bezier_decls); setRedrawFunctionClass(class, RedrawAreaBezier); succeed; }