Shamusworld >> Repos - architektonas/blob - src/drawingview.cpp

   1 // drawingview.cpp
   2 //
   3 // Part of the Architektonas Project
   4 // (C) 2011 Underground Software
   5 // See the README and GPLv3 files for licensing and warranty information
   6 //
   7 // JLH = James L. Hammons <jlhamm@acm.org>
   8 //
   9 // Who  When        What
  10 // ---  ----------  -------------------------------------------------------------
  11 // JLH  03/22/2011  Created this file
  12 //
  13
  14 // FIXED:
  15 //
  16 //
  17 // STILL TO BE DONE:
  18 //
  19 //
  20
  21 // Uncomment this for debugging...
  22 //#define DEBUG
  23 //#define DEBUGFOO                              // Various tool debugging...
  24 //#define DEBUGTP                               // Toolpalette debugging...
  25
  26 #include "drawingview.h"
  27
  28 #include <stdint.h>
  29 #include "mathconstants.h"
  30
  31 #include "arc.h"
  32 #include "circle.h"
  33 #include "dimension.h"
  34 #include "line.h"
  35
  36
  37 DrawingView::DrawingView(QWidget * parent/*= NULL*/): QWidget(parent),
  38 //      scale(1.0), offsetX(-10), offsetY(-10), tool(TOOLSelect),
  39 //      ptHighlight(-1), oldPtHighlight(-1), ptNextHighlight(-1), oldPtNextHighlight(-1),
  40 //      polyFirstPoint(true)
  41         scale(1.0), offsetX(-10), offsetY(-10),
  42         document(Vector(0, 0)),
  43         gridSpacing(32.0), collided(false)
  44 {
  45         setBackgroundRole(QPalette::Base);
  46         setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
  47
  48 //      toolPalette = new ToolWindow();
  49 //      CreateCursors();
  50 //      setCursor(cur[TOOLSelect]);
  51 //      setMouseTracking(true);
  52
  53         Line * line = new Line(Vector(5, 5), Vector(50, 40), &document);
  54         document.Add(line);
  55         document.Add(new Line(Vector(50, 40), Vector(10, 83), &document));
  56         document.Add(new Line(Vector(10, 83), Vector(17, 2), &document));
  57         document.Add(new Circle(Vector(100, 100), 36, &document));
  58         document.Add(new Circle(Vector(50, 150), 49, &document));
  59         document.Add(new Arc(Vector(300, 300), 32, PI / 4.0, PI * 1.3, &document)),
  60         document.Add(new Arc(Vector(200, 200), 60, PI / 2.0, PI * 1.5, &document));
  61 #if 1
  62         Dimension * dimension = new Dimension(Vector(0, 0), Vector(0, 0), &document);
  63         line->SetDimensionOnLine(dimension);
  64 //      line->SetDimensionOnPoint2(dimension);
  65         document.Add(dimension);
  66 #else
  67         // Alternate way to do the above...
  68         line->SetDimensionOnLine();
  69 #endif
  70 }
  71
  72 QPoint DrawingView::GetAdjustedMousePosition(QMouseEvent * event)
  73 {
  74         // This is undoing the transform, e.g. going from client coords to local coords.
  75         // In essence, the height - y is height + (y * -1), the (y * -1) term doing the
  76         // conversion of the y-axis from increasing bottom to top.
  77         return QPoint(offsetX + event->x(), offsetY + (size().height() - event->y()));
  78 }
  79
  80 QPoint DrawingView::GetAdjustedClientPosition(int x, int y)
  81 {
  82         // VOODOO ALERT (ON Y COMPONENT!!!!) (eh?)
  83         // No voodoo here, it's just grouped wrong to see it. It should be:
  84         // -offsetY + (size.height() + (y * -1.0)) <-- this is wrong, offsetY should be positive
  85         return QPoint(-offsetX + x, (size().height() - (-offsetY + y)) * +1.0);
  86 }
  87
  88 void DrawingView::paintEvent(QPaintEvent * /*event*/)
  89 {
  90         QPainter painter(this);
  91         painter.setRenderHint(QPainter::Antialiasing);
  92
  93 #if 0
  94         painter.translate(QPoint(-offsetX, size.height() - (-offsetY)));
  95         painter.scale(1.0, -1.0);
  96 #else
  97         QTransform transform;
  98 //order of operations is important! N.B.: Can't use scaling other than 1.0, it
  99 //causes lines to look strange (i.e., it scales the pen strokes too)
 100 //      transform.translate(-offsetX, size().height() - (-offsetY));
 101         transform.scale(1.0, -1.0);
 102         transform.translate(-offsetX, -size().height() - offsetY);
 103 //      transform.scale(0.25, 0.25);
 104         painter.setTransform(transform);
 105 #endif
 106         Object::SetViewportHeight(size().height());
 107
 108         // Draw coordinate axes
 109
 110         painter.setPen(QPen(Qt::blue, 1.0, Qt::DotLine));
 111         painter.drawLine(0, -16384, 0, 16384);
 112         painter.drawLine(-16384, 0, 16384, 0);
 113
 114 // Maybe we can make the grid into a background brush instead, and let Qt deal
 115 // with it???
 116         // Draw grid
 117
 118 #if 0
 119         painter.setPen(QPen(QColor(90, 90, 90), 1.0, Qt::DotLine));
 120
 121         //these two loops kill performance!
 122         for(double x=0; x<size().width(); x+=gridSpacing*10.0)
 123                 p.drawLine((int)x, -16384, (int)x, 16384);
 124
 125         for(double y=0; y<size().height(); y+=gridSpacing*10.0)
 126                 p.drawLine(-16384, (int)y, 16384, (int)y);
 127 #endif
 128
 129         painter.setPen(QPen(Qt::black, 1.0, Qt::SolidLine));
 130
 131         for(double x=0; x<size().width(); x+=gridSpacing)
 132                 for(double y=0; y<size().height(); y+=gridSpacing)
 133                         painter.drawPoint((int)x, (int)y);
 134
 135         // The top level document takes care of rendering for us...
 136         document.Draw(&painter);
 137 }
 138
 139 void DrawingView::mousePressEvent(QMouseEvent * event)
 140 {
 141         if (event->button() == Qt::LeftButton)
 142         {
 143                 QPoint pt = GetAdjustedMousePosition(event);
 144                 Vector point(pt.x(), pt.y());
 145
 146                 collided = document.Collided(point);
 147
 148                 if (collided)
 149                         update();       // Do an update if collided with at least *one* object in the document
 150         }
 151 }
 152
 153 void DrawingView::mouseMoveEvent(QMouseEvent * event)
 154 {
 155         QPoint pt = GetAdjustedMousePosition(event);
 156         Vector point(pt.x(), pt.y());
 157
 158         // Grid processing...
 159 #if 1
 160         // This looks strange, but it's really quite simple: We want a point that's
 161         // more than half-way to the next grid point to snap there while conversely
 162         // we want a point that's less than half-way to to the next grid point then
 163         // snap to the one before it. So we add half of the grid spacing to the
 164         // point, then divide by it so that we can remove the fractional part, then
 165         // multiply it back to get back to the correct answer.
 166         if (event->buttons() & Qt::LeftButton)
 167         {
 168                 point += gridSpacing / 2.0;                                     // *This* adds to Z!!!
 169                 point /= gridSpacing;
 170                 point.x = floor(point.x);//need to fix this for negative numbers...
 171                 point.y = floor(point.y);
 172                 point.z = 0;                                                            // Make *sure* Z doesn't go anywhere!!!
 173                 point *= gridSpacing;
 174         }
 175 #endif
 176 //we should keep track of the last point here and only pass this down *if* the point
 177 //changed...
 178         document.PointerMoved(point);
 179
 180         if (document.NeedsUpdate())
 181                 update();
 182 }
 183
 184 void DrawingView::mouseReleaseEvent(QMouseEvent * event)
 185 {
 186         if (event->button() == Qt::LeftButton)
 187         {
 188                 document.PointerReleased();
 189
 190 //We need to update especially if nothing collided and the state needs to change. !!! FIX !!!
 191 //could set it up to use the document's update function (assumes that all object updates
 192 //are being reported correctly:
 193 //              if (document.NeedsUpdate())
 194 //              if (collided)
 195                         update();       // Do an update if collided with at least *one* object in the document
 196         }
 197 }
 198
 199
 200 #if 0
 201 QSize DrawingView::minimumSizeHint() const
 202 {
 203         return QSize(50, 50);
 204 }
 205
 206 QSize DrawingView::sizeHint() const
 207 {
 208         return QSize(400, 400);
 209 }
 210
 211 void DrawingView::CreateCursors(void)
 212 {
 213         int hotx[8] = {  1,  1, 11, 15,  1,  1,  1,  1 };
 214         int hoty[8] = {  1,  1, 11, 13,  1,  1,  1,  1 };
 215
 216         for(int i=0; i<8; i++)
 217         {
 218                 QString s;
 219                 s.sprintf(":/res/cursor%u.png", i+1);
 220                 QPixmap pmTmp(s);
 221                 cur[i] = QCursor(pmTmp, hotx[i], hoty[i]);
 222         }
 223 }
 224
 225 /*
 226 TODO:
 227  o  Different colors for polys on selected points
 228  o  Different colors for handles on non-selected polys
 229  o  Line of sight (dashed, dotted) for off-curve points
 230  o  Repaints for press/release of CTRL/SHIFT during point creation
 231 */
 232 void DrawingView::paintEvent(QPaintEvent * /*event*/)
 233 {
 234         QPainter p(this);
 235 //hm, causes lockup
 236 //      p.setRenderHint(QPainter::Antialiasing);
 237 //Doesn't do crap!
 238 //dc.SetBackground(*wxWHITE_BRUSH);
 239
 240 // Due to the screwiness of wxWidgets coord system, the origin is ALWAYS
 241 // the upper left corner--regardless of axis orientation, etc...
 242 //      int width, height;
 243 //      dc.GetSize(&width, &height);
 244         QSize winSize = size();
 245
 246 //      dc.SetDeviceOrigin(-offsetX, height - (-offsetY));
 247 //      dc.SetAxisOrientation(true, true);
 248         p.translate(QPoint(-offsetX, winSize.height() - (-offsetY)));
 249         p.scale(1.0, -1.0);
 250
 251 // Scrolling can be done by using OffsetViewportOrgEx
 252 // Scaling can be done by adjusting SetWindowExtEx (it's denominator of txform)
 253 // you'd use: % = ViewportExt / WindowExt
 254 // But it makes the window look like crap: fuggetuboutit.
 255 // Instead, we have to scale EVERYTHING by hand. Crap!
 256 // It's not *that* bad, but not as convenient either...
 257
 258 //      dc.SetPen(*(wxThePenList->FindOrCreatePen(wxColour(0x00, 0x00, 0xFF), 1, wxDOT)));
 259 ////    dc.DrawLine(0, 0, 10, 10);
 260         p.setPen(QPen(Qt::blue, 1.0, Qt::DotLine));
 261
 262     // Draw coordinate axes
 263
 264 //      dc.CrossHair(0, 0);
 265         p.drawLine(0, -16384, 0, 16384);
 266         p.drawLine(-16384, 0, 16384, 0);
 267
 268     // Draw points
 269
 270         for(int i=0; i<pts.GetNumPoints(); i++)
 271         {
 272                 if (i == ptHighlight)
 273                 {
 274 //                      dc.SetPen(*(wxThePenList->FindOrCreatePen(wxColour(0xFF, 0x00, 0x00), 1, wxSOLID)));
 275 ////                    SelectObject(hdc, hRedPen1);
 276                         p.setPen(QPen(Qt::red, 1.0, Qt::SolidLine));
 277
 278                         if (pts.GetOnCurve(i))
 279                         {
 280                                 DrawSquareDotN(p, pts.GetX(i), pts.GetY(i), 7);
 281                                 DrawSquareDotN(p, pts.GetX(i), pts.GetY(i), 9);
 282                         }
 283                         else
 284                         {
 285                                 DrawRoundDotN(p, pts.GetX(i), pts.GetY(i), 7);
 286                                 DrawRoundDotN(p, pts.GetX(i), pts.GetY(i), 9);
 287                         }
 288                 }
 289                 else if ((i == ptHighlight || i == ptNextHighlight) && tool == TOOLAddPt)
 290                 {
 291 //                      dc.SetPen(*(wxThePenList->FindOrCreatePen(wxColour(0x00, 0xAF, 0x00), 1, wxSOLID)));
 292 ////                    SelectObject(hdc, hGreenPen1);
 293                         p.setPen(QPen(Qt::green, 1.0, Qt::SolidLine));
 294
 295                         if (pts.GetOnCurve(i))
 296                         {
 297                                 DrawSquareDotN(p, pts.GetX(i), pts.GetY(i), 7);
 298                                 DrawSquareDotN(p, pts.GetX(i), pts.GetY(i), 9);
 299                         }
 300                         else
 301                         {
 302                                 DrawRoundDotN(p, pts.GetX(i), pts.GetY(i), 7);
 303                                 DrawRoundDotN(p, pts.GetX(i), pts.GetY(i), 9);
 304                         }
 305                 }
 306                 else
 307                 {
 308 //                      dc.SetPen(*(wxThePenList->FindOrCreatePen(wxColour(0x00, 0x00, 0x00), 1, wxSOLID)));
 309 ////                    SelectObject(hdc, hBlackPen1);
 310                         p.setPen(QPen(Qt::black, 1.0, Qt::SolidLine));
 311
 312                         if (pts.GetOnCurve(i))
 313                                 DrawSquareDot(p, pts.GetX(i), pts.GetY(i));
 314                         else
 315                                 DrawRoundDot(p, pts.GetX(i), pts.GetY(i));
 316                 }
 317
 318                 if (tool == TOOLDelPt && i == ptHighlight)
 319                 {
 320 #if 0
 321                         dc.SetPen(*(wxThePenList->FindOrCreatePen(wxColour(0xFF, 0x00, 0x00), 1, wxSOLID)));
 322 //                      SelectObject(hdc, hRedPen1);
 323 //                      MoveToEx(hdc, pts.GetX(i) - 5, pts.GetY(i) - 5, NULL);
 324 //                      LineTo(hdc, pts.GetX(i) + 5, pts.GetY(i) + 5);
 325 //                      LineTo(hdc, pts.GetX(i) - 5, pts.GetY(i) - 5);//Lameness!
 326 //                      MoveToEx(hdc, pts.GetX(i) - 5, pts.GetY(i) + 5, NULL);
 327 //                      LineTo(hdc, pts.GetX(i) + 5, pts.GetY(i) - 5);
 328 //                      LineTo(hdc, pts.GetX(i) - 5, pts.GetY(i) + 5);//More lameness!!
 329 #endif
 330                         p.setPen(QPen(Qt::red, 1.0, Qt::SolidLine));
 331                         p.drawLine(pts.GetX(i) - 5, pts.GetY(i) - 5, pts.GetX(i) + 5, pts.GetY(i) + 5);
 332                         p.drawLine(pts.GetX(i) + 5, pts.GetY(i) - 5, pts.GetX(i) - 5, pts.GetY(i) + 5);
 333                 }
 334         }
 335
 336 ////            SelectObject(hdc, hBlackPen1);
 337 //      dc.SetPen(*(wxThePenList->FindOrCreatePen(wxColour(0x00, 0x00, 0x00), 1, wxSOLID)));
 338         p.setPen(QPen(Qt::black, 1.0, Qt::SolidLine));
 339
 340         // Draw curve formed by points
 341
 342         for(int poly=0; poly<pts.GetNumPolys(); poly++)
 343         {
 344                 if (pts.GetNumPoints(poly) > 2)
 345                 {
 346                         // Initial move...
 347                         // If it's not on curve, then move to it, otherwise move to last point...
 348
 349                         int x, y;
 350
 351                         if (pts.GetOnCurve(poly, pts.GetNumPoints(poly) - 1))
 352                                 x = (int)pts.GetX(poly, pts.GetNumPoints(poly) - 1), y = (int)pts.GetY(poly, pts.GetNumPoints(poly) - 1);
 353                         else
 354                                 x = (int)pts.GetX(poly, 0), y = (int)pts.GetY(poly, 0);
 355
 356                         for(int i=0; i<pts.GetNumPoints(poly); i++)
 357                         {
 358                                 if (pts.GetOnCurve(poly, i))
 359 //                                      LineTo(hdc, pts.GetX(poly, i), pts.GetY(poly, i));
 360                                 {
 361                                         p.drawLine(x, y, pts.GetX(poly, i), pts.GetY(poly, i));
 362                                         x = (int)pts.GetX(poly, i), y = (int)pts.GetY(poly, i);
 363                                 }
 364                                 else
 365                                 {
 366                                         uint32 prev = pts.GetPrev(poly, i), next = pts.GetNext(poly, i);
 367                                         float px = pts.GetX(poly, prev), py = pts.GetY(poly, prev),
 368                                                 nx = pts.GetX(poly, next), ny = pts.GetY(poly, next);
 369
 370                                         if (!pts.GetOnCurve(poly, prev))
 371                                                 px = (px + pts.GetX(poly, i)) / 2.0f,
 372                                                 py = (py + pts.GetY(poly, i)) / 2.0f;
 373
 374                                         if (!pts.GetOnCurve(poly, next))
 375                                                 nx = (nx + pts.GetX(poly, i)) / 2.0f,
 376                                                 ny = (ny + pts.GetY(poly, i)) / 2.0f;
 377
 378                                         Bezier(p, point(px, py), point(pts.GetX(poly, i), pts.GetY(poly, i)), point(nx, ny));
 379                                         x = (int)nx, y = (int)ny;
 380
 381                                         if (pts.GetOnCurve(poly, next))
 382                                                 i++;                                    // Following point is on curve, so move past it
 383                                 }
 384                         }
 385                 }
 386         }
 387 }
 388
 389 void DrawingView::mousePressEvent(QMouseEvent * event)
 390 {
 391         if (event->button() == Qt::RightButton)
 392         {
 393                 toolPalette->move(event->globalPos());
 394                 toolPalette->setVisible(true);
 395                 setCursor(cur[TOOLSelect]);
 396                 toolPalette->prevTool = TOOLSelect;
 397         }
 398         else if (event->button() == Qt::MidButton)
 399         {
 400                 setCursor(cur[2]);                                                      // Scrolling cursor
 401         }
 402         else if (event->button() == Qt::LeftButton)
 403         {
 404                 if (tool == TOOLScroll || tool == TOOLZoom)
 405 ;//meh                  CaptureMouse();                                         // Make sure we capture the mouse when in scroll/zoom mode
 406                 else if (tool == TOOLAddPt)             // "Add Point" tool
 407                 {
 408                         if (pts.GetNumPoints() > 0)
 409                         {
 410                                 QPoint pt = GetAdjustedMousePosition(event);
 411                                 pts.InsertPoint(pts.GetNext(ptHighlight), pt.x(), pt.y(), ((event->modifiers() == Qt::ShiftModifier || event->modifiers() == Qt::ControlModifier) ? false : true));
 412                                 ptHighlight = ptNextHighlight;
 413                                 update();
 414                         }
 415                 }
 416                 else if (tool == TOOLAddPoly)   // "Add Poly" tool
 417                 {
 418 #ifdef DEBUGFOO
 419 WriteLogMsg("Adding point... # polys: %u, # points: %u", pts.GetNumPolys(), pts.GetNumPoints());
 420 #endif
 421                         if (polyFirstPoint)
 422                         {
 423                                 polyFirstPoint = false;
 424                                 pts.AddNewPolyAtEnd();
 425                         }
 426
 427                         QPoint pt = GetAdjustedMousePosition(event);
 428 //printf("GetAdjustedMousePosition = %i, %i\n", pt.x(), pt.y());
 429                         // Append a point to the end of the structure
 430                         pts += IPoint(pt.x(), pt.y(), ((event->modifiers() == Qt::ShiftModifier || event->modifiers() == Qt::ControlModifier) ? false : true));
 431                         ptHighlight = pts.GetNumPoints() - 1;
 432                         update();
 433 #ifdef DEBUGFOO
 434 WriteLogMsg(" --> [# polys: %u, # points: %u]\n", pts.GetNumPolys(), pts.GetNumPoints());
 435 #endif
 436                 }
 437                 else if (tool == TOOLSelect || tool == TOOLPolySelect)
 438                 {
 439                         if (pts.GetNumPoints() > 0)
 440                         {
 441                                 pt = GetAdjustedClientPosition(pts.GetX(ptHighlight), pts.GetY(ptHighlight));
 442 //printf("GetAdjustedClientPosition = %i, %i\n", pt.x(), pt.y());
 443 //                              WarpPointer(pt.x, pt.y);
 444                                 QCursor::setPos(mapToGlobal(pt));
 445
 446                                 if (event->modifiers() == Qt::ShiftModifier || event->modifiers() == Qt::ControlModifier)
 447                                 {
 448                                         pts.SetOnCurve(ptHighlight, !pts.GetOnCurve(ptHighlight));
 449                                         update();
 450                                 }
 451                         }
 452                 }
 453                 else if (tool == TOOLDelPt)
 454                 {
 455                         if (pts.GetNumPoints() > 0)
 456 //Or could use:
 457 //                      if (ptHighlight != -1)
 458                         {
 459 //This assumes that WM_MOUSEMOVE happens before this!
 460 //The above commented out line should take care of this contingency... !!! FIX !!!
 461                                 pts.DeletePoint(ptHighlight);
 462                                 update();
 463                         }
 464                 }
 465         }
 466
 467         event->accept();
 468 }
 469
 470 void DrawingView::mouseMoveEvent(QMouseEvent * event)
 471 {
 472         if (event->buttons() == Qt::RightButton)
 473         {
 474                 ToolType newTool = toolPalette->FindSelectedTool();
 475
 476                 if (newTool != toolPalette->prevTool)
 477                 {
 478                         toolPalette->prevTool = newTool;
 479                         toolPalette->repaint();
 480                 }
 481         }
 482         else if (event->buttons() == Qt::MidButton)
 483         {
 484                 // Calc offset from previous point
 485                 pt = event->pos();
 486                 ptOffset = QPoint(pt.x() - ptPrevious.x(), pt.y() - ptPrevious.y());
 487
 488 // Then multiply it by the scaling factor. Whee!
 489                 // This looks wacky because we're using screen coords for the offset...
 490                 // Otherwise, we would subtract both offsets!
 491                 offsetX -= ptOffset.x(), offsetY += ptOffset.y();
 492                 update();
 493                 ptPrevious = pt;
 494         }
 495         else if (event->buttons() == Qt::LeftButton)
 496         {
 497 #if 0
 498                         if (tool == TOOLScroll)
 499                         {
 500                             // Extract current point from lParam/calc offset from previous point
 501
 502                                 pt = e.GetPosition();
 503                                 ptOffset.x = pt.x - ptPrevious.x,
 504                                 ptOffset.y = pt.y - ptPrevious.y;
 505
 506                                 // NOTE: OffsetViewportOrg operates in DEVICE UNITS...
 507
 508 //Seems there's no equivalent for this in wxWidgets...!
 509 //!!! FIX !!!
 510 //                              hdc = GetDC(hWnd);
 511 //                              OffsetViewportOrgEx(hdc, ptOffset.x, ptOffset.y, NULL);
 512 //                              ReleaseDC(hWnd, hdc);
 513
 514 // this shows that it works, so the logic above must be faulty...
 515 // And it is. It should convert the coords first, then do the subtraction to figure the offset...
 516 // Above: DONE
 517 // Then multiply it by the scaling factor. Whee!
 518                                 // This looks wacky because we're using screen coords for the offset...
 519                                 // Otherwise, we would subtract both offsets!
 520                                 offsetX -= ptOffset.x, offsetY += ptOffset.y;
 521                                 Refresh();
 522                         }
 523                         else
 524 #endif
 525                         if (tool == TOOLAddPt || tool == TOOLAddPoly || tool == TOOLSelect)
 526                         {
 527                                 if (tool != TOOLAddPt || pts.GetNumPoints() > 0)//yecch.
 528                                 {
 529 //temporary, for testing. BTW, Select drag bug is here...!
 530 #if 1
 531                                         QPoint pt2 = GetAdjustedMousePosition(event);
 532                                         pts.SetXY(ptHighlight, pt2.x(), pt2.y());
 533                                         update();
 534 #endif
 535                                 }
 536                         }
 537                         else if (tool == TOOLPolySelect)
 538                         {
 539                                 if (pts.GetNumPoints() > 0)
 540                                 {
 541                                         QPoint pt2 = GetAdjustedMousePosition(event);
 542                                         // Should also set onCurve here as well, depending on keystate
 543 //Or should we?
 544                                         pts.OffsetPoly(pts.GetPoly(ptHighlight), pt2.x() - pts.GetX(ptHighlight), pt2.y() - pts.GetY(ptHighlight));
 545                                         update();
 546                                 }
 547                         }
 548         }
 549         else if (event->buttons() == Qt::NoButton)
 550         {
 551                 // Moving, not dragging...
 552                 if (tool == TOOLSelect || tool == TOOLDelPt || tool == TOOLAddPt
 553                         || tool == TOOLPolySelect)// || tool == TOOLAddPoly)
 554                 {
 555                         QPoint pt2 = GetAdjustedMousePosition(event);
 556                         double closest = 1.0e+99;
 557
 558                         for(int i=0; i<pts.GetNumPoints(); i++)
 559                         {
 560                                 double dist = ((pt2.x() - pts.GetX(i)) * (pt2.x() - pts.GetX(i)))
 561                                         + ((pt2.y() - pts.GetY(i)) * (pt2.y() - pts.GetY(i)));
 562
 563                                 if (dist < closest)
 564                                         closest = dist, ptHighlight = i;
 565                         }
 566
 567                         if (ptHighlight != oldPtHighlight)
 568                         {
 569                                 oldPtHighlight = ptHighlight;
 570                                 update();
 571                         }
 572
 573                         // What follows here looks like voodoo, but is really simple. What we do is
 574                         // check to see if the mouse point has a perpendicular intersection with any of
 575                         // the line segments. If it does, calculate the length of the perpendicular
 576                         // and choose the smallest length. If there is no perpendicular, then choose the
 577                         // length of line connecting the closer of either the first endpoint or the
 578                         // second and choose the smallest of those.
 579
 580                         // There is one bit of math that looks like voodoo to me ATM--will explain once
 581                         // I understand it better (the calculation of the length of the perpendicular).
 582
 583                         if (pts.GetNumPoints() > 1 && tool == TOOLAddPt)
 584                         {
 585                                 double smallest = 1.0e+99;
 586
 587                                 for(int i=0; i<pts.GetNumPoints(); i++)
 588                                 {
 589                                         int32 p1x = pts.GetX(i), p1y = pts.GetY(i),
 590                                                 p2x = pts.GetX(pts.GetNext(i)), p2y = pts.GetY(pts.GetNext(i));
 591
 592                                         vector ls(p2x, p2y, 0, p1x, p1y, 0), v1(pt2.x(), pt2.y(), 0, p1x, p1y, 0),
 593                                                 v2(pt2.x(), pt2.y(), 0, p2x, p2y, 0);
 594                                         double pp = ls.dot(v1) / ls.length(), dist;
 595 // Geometric interpretation:
 596 // pp is the paremeterized point on the vector ls where the perpendicular intersects ls.
 597 // If pp < 0, then the perpendicular lies beyond the 1st endpoint. If pp > length of ls,
 598 // then the perpendicular lies beyond the 2nd endpoint.
 599
 600                                         if (pp < 0.0)
 601                                                 dist = v1.length();
 602                                         else if (pp > ls.length())
 603                                                 dist = v2.length();
 604                                         else                                    // distance = ?Det?(ls, v1) / |ls|
 605                                                 dist = fabs((ls.x * v1.y - v1.x * ls.y) / ls.length());
 606
 607 //The answer to the above looks like it might be found here:
 608 //
 609 //If the segment endpoints are s and e, and the point is p, then the test for the perpendicular
 610 //intercepting the segment is equivalent to insisting that the two dot products {s-e}.{s-p} and
 611 //{e-s}.{e-p} are both non-negative.  Perpendicular distance from the point to the segment is
 612 //computed by first computing the area of the triangle the three points form, then dividing by the
 613 //length of the segment.  Distances are done just by the Pythagorean theorem.  Twice the area of the
 614 //triangle formed by three points is the determinant of the following matrix:
 615 //
 616 //sx sy 1
 617 //ex ey 1
 618 //px py 1
 619 //
 620 //By translating the start point to the origin, this can be rewritten as:
 621 //By subtracting row 1 from all rows, you get the following:
 622 //[because sx = sy = 0. you could leave out the -sx/y terms below. because we subtracted
 623 // row 1 from all rows (including row 1) row 1 turns out to be zero. duh!]
 624 //
 625 //0         0         0
 626 //(ex - sx) (ey - sy) 0
 627 //(px - sx) (py - sy) 0
 628 //
 629 //which greatly simplifies the calculation of the determinant.
 630
 631                                         if (dist < smallest)
 632                                                 smallest = dist, ptNextHighlight = pts.GetNext(i), ptHighlight = i;
 633                                 }
 634
 635                                 if (ptNextHighlight != oldPtNextHighlight)
 636                                 {
 637                                         oldPtNextHighlight = ptNextHighlight;
 638                                         update();
 639                                 }
 640                         }
 641                 }
 642
 643                 ptPrevious = event->pos();
 644         }
 645
 646         event->accept();
 647 }
 648
 649 void DrawingView::mouseReleaseEvent(QMouseEvent * event)
 650 {
 651         if (event->button() == Qt::RightButton)
 652         {
 653                 ToolType newTool = toolPalette->FindSelectedTool();
 654
 655                 // We only change the tool if a new one was actually selected. Otherwise, we do nothing.
 656                 if (newTool != TOOLNone)
 657                 {
 658                         tool = newTool;
 659
 660                         if (tool == TOOLScroll || tool == TOOLZoom || tool == TOOLAddPoly
 661                                 || tool == TOOLDelPoly)
 662                                 ptHighlight = -1;
 663
 664                         if (tool == TOOLAddPoly)
 665                                 polyFirstPoint = true;
 666                 }
 667
 668                 toolPalette->setVisible(false);
 669                 setCursor(cur[tool]);
 670                 // Just in case we changed highlighting style with the new tool...
 671                 update();
 672         }
 673         else if (event->button() == Qt::MidButton)
 674         {
 675                 setCursor(cur[tool]);                                           // Restore previous cursor
 676         }
 677         else if (event->button() == Qt::LeftButton)
 678         {
 679 //              if (tool == TOOLScroll || tool == TOOLZoom)
 680 //                      ReleaseMouse();
 681 //this is prolly too much
 682                 ((TTEdit *)qApp)->charWnd->MakePathFromPoints(&pts);
 683                 ((TTEdit *)qApp)->charWnd->update();
 684         }
 685
 686         event->accept();
 687 }
 688 #endif