1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228
|
/*
Scan Tailor - Interactive post-processing tool for scanned pages.
Copyright (C) Joseph Artsimovich <joseph.artsimovich@gmail.com>
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 3 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, see <http://www.gnu.org/licenses/>.
*/
#include "ImageViewBase.h"
#include "ImageViewBase.h.moc"
#include "NonCopyable.h"
#include "ImagePresentation.h"
#include "OpenGLSupport.h"
#include "PixmapRenderer.h"
#include "BackgroundExecutor.h"
#include "Dpm.h"
#include "Dpi.h"
#include "ScopedIncDec.h"
#include "imageproc/PolygonUtils.h"
#include "imageproc/Transform.h"
#include "config.h"
#include <QScrollBar>
#include <QPointer>
#include <QAtomicInt>
#include <QPaintEngine>
#include <QPainter>
#include <QPainterPath>
#include <QBrush>
#include <QLineF>
#include <QPolygonF>
#include <QPalette>
#include <QMouseEvent>
#include <QWheelEvent>
#include <QResizeEvent>
#include <QStatusTipEvent>
#include <QApplication>
#include <QSettings>
#include <QVariant>
#include <Qt>
#include <QDebug>
#include <algorithm>
#include <assert.h>
#include <math.h>
#ifdef ENABLE_OPENGL
#include <QGLWidget>
#include <QGLFormat>
#endif
using namespace imageproc;
class ImageViewBase::HqTransformTask :
public AbstractCommand0<IntrusivePtr<AbstractCommand0<void> > >,
public QObject
{
DECLARE_NON_COPYABLE(HqTransformTask)
public:
HqTransformTask(
ImageViewBase* image_view,
QImage const& image, QTransform const& xform,
QSize const& target_size);
void cancel() { m_ptrResult->cancel(); }
bool const isCancelled() const { return m_ptrResult->isCancelled(); }
virtual IntrusivePtr<AbstractCommand0<void> > operator()();
private:
class Result : public AbstractCommand0<void>
{
public:
Result(ImageViewBase* image_view);
void setData(QPoint const& origin, QImage const& hq_image);
void cancel() { m_cancelFlag.fetchAndStoreRelaxed(1); }
bool isCancelled() const { return m_cancelFlag.fetchAndAddRelaxed(0) != 0; }
virtual void operator()();
private:
QPointer<ImageViewBase> m_ptrImageView;
QPoint m_origin;
QImage m_hqImage;
mutable QAtomicInt m_cancelFlag;
};
IntrusivePtr<Result> m_ptrResult;
QImage m_image;
QTransform m_xform;
QSize m_targetSize;
};
/**
* \brief Temporarily adjust the widget focal point, then change it back.
*
* When adjusting and restoring the widget focal point, the pixmap
* focal point is recalculated accordingly.
*/
class ImageViewBase::TempFocalPointAdjuster
{
public:
/**
* Change the widget focal point to obj.centeredWidgetFocalPoint().
*/
TempFocalPointAdjuster(ImageViewBase& obj);
/**
* Change the widget focal point to \p temp_widget_fp
*/
TempFocalPointAdjuster(ImageViewBase& obj, QPointF temp_widget_fp);
/**
* Restore the widget focal point.
*/
~TempFocalPointAdjuster();
private:
ImageViewBase& m_rObj;
QPointF m_origWidgetFP;
};
class ImageViewBase::TransformChangeWatcher
{
public:
TransformChangeWatcher(ImageViewBase& owner);
~TransformChangeWatcher();
private:
ImageViewBase& m_rOwner;
QTransform m_imageToVirtual;
QTransform m_virtualToWidget;
QRectF m_virtualDisplayArea;
};
ImageViewBase::ImageViewBase(
QImage const& image, ImagePixmapUnion const& downscaled_version,
ImagePresentation const& presentation, Margins const& margins)
: m_image(image),
m_virtualImageCropArea(presentation.cropArea()),
m_virtualDisplayArea(presentation.displayArea()),
m_imageToVirtual(presentation.transform()),
m_virtualToImage(presentation.transform().inverted()),
m_lastMaximumViewportSize(maximumViewportSize()),
m_margins(margins),
m_zoom(1.0),
m_transformChangeWatchersActive(0),
m_ignoreScrollEvents(0),
m_ignoreResizeEvents(0),
m_hqTransformEnabled(true)
{
#ifdef ENABLE_OPENGL
if (QSettings().value("settings/use_3d_acceleration", false) != false) {
if (OpenGLSupport::supported()) {
QGLFormat format;
format.setSampleBuffers(true);
format.setStencil(true);
format.setAlpha(true);
format.setRgba(true);
format.setDepth(false);
// Most of hardware refuses to work for us with direct rendering enabled.
format.setDirectRendering(false);
setViewport(new QGLWidget(format));
}
}
#endif
setFrameShape(QFrame::NoFrame);
viewport()->setFocusPolicy(Qt::WheelFocus);
if (downscaled_version.isNull()) {
m_pixmap = QPixmap::fromImage(createDownscaledImage(image));
} else if (downscaled_version.pixmap().isNull()) {
m_pixmap = QPixmap::fromImage(downscaled_version.image());
} else {
m_pixmap = downscaled_version.pixmap();
}
m_pixmapToImage.scale(
(double)m_image.width() / m_pixmap.width(),
(double)m_image.height() / m_pixmap.height()
);
m_widgetFocalPoint = centeredWidgetFocalPoint();
m_pixmapFocalPoint = m_virtualToImage.map(virtualDisplayRect().center());
m_timer.setSingleShot(true);
m_timer.setInterval(150); // msec
connect(
&m_timer, SIGNAL(timeout()),
this, SLOT(initiateBuildingHqVersion())
);
updateWidgetTransformAndFixFocalPoint(CENTER_IF_FITS);
interactionState().setDefaultStatusTip(
tr("Use the mouse wheel or +/- to zoom. When zoomed, dragging is possible.")
);
ensureStatusTip(interactionState().statusTip());
connect(horizontalScrollBar(), SIGNAL(sliderReleased()), SLOT(updateScrollBars()));
connect(verticalScrollBar(), SIGNAL(sliderReleased()), SLOT(updateScrollBars()));
connect(horizontalScrollBar(), SIGNAL(valueChanged(int)), SLOT(reactToScrollBars()));
connect(verticalScrollBar(), SIGNAL(valueChanged(int)), SLOT(reactToScrollBars()));
}
ImageViewBase::~ImageViewBase()
{
}
void
ImageViewBase::hqTransformSetEnabled(bool const enabled)
{
if (!enabled && m_hqTransformEnabled) {
// Turning off.
m_hqTransformEnabled = false;
if (m_ptrHqTransformTask.get()) {
m_ptrHqTransformTask->cancel();
m_ptrHqTransformTask.reset();
}
if (!m_hqPixmap.isNull()) {
m_hqPixmap = QPixmap();
update();
}
} else if (enabled && !m_hqTransformEnabled) {
// Turning on.
m_hqTransformEnabled = true;
update();
}
}
QImage
ImageViewBase::createDownscaledImage(QImage const& image)
{
assert(!image.isNull());
// Original and downscaled DPM.
Dpm const o_dpm(image);
Dpm const d_dpm(Dpi(300, 300));
int const o_w = image.width();
int const o_h = image.height();
int d_w = o_w * d_dpm.horizontal() / o_dpm.horizontal();
int d_h = o_h * d_dpm.vertical() / o_dpm.vertical();
d_w = qBound(1, d_w, o_w);
d_h = qBound(1, d_h, o_h);
if (d_w * 1.2 > o_w || d_h * 1.2 > o_h) {
// Sizes are close - no point in downscaling.
return image;
}
QTransform xform;
xform.scale((double)d_w / o_w, (double)d_h / o_h);
return transform(
image, xform, QRect(0, 0, d_w, d_h),
OutsidePixels::assumeColor(Qt::white)
);
}
QRectF
ImageViewBase::maxViewportRect() const
{
QRectF const viewport_rect(QPointF(0, 0), maximumViewportSize());
QRectF r(viewport_rect);
r.adjust(
m_margins.left(), m_margins.top(),
-m_margins.right(), -m_margins.bottom()
);
if (r.isEmpty()) {
return QRectF(viewport_rect.center(), viewport_rect.center());
}
return r;
}
QRectF
ImageViewBase::dynamicViewportRect() const
{
QRectF const viewport_rect(viewport()->rect());
QRectF r(viewport_rect);
r.adjust(
m_margins.left(), m_margins.top(),
-m_margins.right(), -m_margins.bottom()
);
if (r.isEmpty()) {
return QRectF(viewport_rect.center(), viewport_rect.center());
}
return r;
}
QRectF
ImageViewBase::getOccupiedWidgetRect() const
{
QRectF const widget_rect(m_virtualToWidget.mapRect(virtualDisplayRect()));
return widget_rect.intersected(dynamicViewportRect());
}
void
ImageViewBase::setWidgetFocalPoint(QPointF const& widget_fp)
{
setNewWidgetFP(widget_fp, /*update =*/true);
}
void
ImageViewBase::adjustAndSetWidgetFocalPoint(QPointF const& widget_fp)
{
adjustAndSetNewWidgetFP(widget_fp, /*update=*/true);
}
void
ImageViewBase::setZoomLevel(double zoom)
{
if (m_zoom != zoom) {
m_zoom = zoom;
updateWidgetTransform();
update();
}
}
void
ImageViewBase::moveTowardsIdealPosition(double const pixel_length)
{
if (pixel_length <= 0) {
// The name implies we are moving *towards* the ideal position.
return;
}
QPointF const ideal_widget_fp(getIdealWidgetFocalPoint(CENTER_IF_FITS));
if (ideal_widget_fp == m_widgetFocalPoint) {
return;
}
QPointF vec(ideal_widget_fp - m_widgetFocalPoint);
double const max_length = sqrt(vec.x() * vec.x() + vec.y() * vec.y());
if (pixel_length >= max_length) {
m_widgetFocalPoint = ideal_widget_fp;
} else {
vec *= pixel_length / max_length;
m_widgetFocalPoint += vec;
}
updateWidgetTransform();
update();
}
void
ImageViewBase::updateTransform(ImagePresentation const& presentation)
{
TransformChangeWatcher const watcher(*this);
TempFocalPointAdjuster const temp_fp(*this);
m_imageToVirtual = presentation.transform();
m_virtualToImage = m_imageToVirtual.inverted();
m_virtualImageCropArea = presentation.cropArea();
m_virtualDisplayArea = presentation.displayArea();
updateWidgetTransform();
update();
}
void
ImageViewBase::updateTransformAndFixFocalPoint(
ImagePresentation const& presentation, FocalPointMode const mode)
{
TransformChangeWatcher const watcher(*this);
TempFocalPointAdjuster const temp_fp(*this);
m_imageToVirtual = presentation.transform();
m_virtualToImage = m_imageToVirtual.inverted();
m_virtualImageCropArea = presentation.cropArea();
m_virtualDisplayArea = presentation.displayArea();
updateWidgetTransformAndFixFocalPoint(mode);
update();
}
void
ImageViewBase::updateTransformPreservingScale(ImagePresentation const& presentation)
{
TransformChangeWatcher const watcher(*this);
TempFocalPointAdjuster const temp_fp(*this);
// An arbitrary line in image coordinates.
QLineF const image_line(0.0, 0.0, 1.0, 1.0);
QLineF const widget_line_before(
(m_imageToVirtual * m_virtualToWidget).map(image_line)
);
m_imageToVirtual = presentation.transform();
m_virtualToImage = m_imageToVirtual.inverted();
m_virtualImageCropArea = presentation.cropArea();
m_virtualDisplayArea = presentation.displayArea();
updateWidgetTransform();
QLineF const widget_line_after(
(m_imageToVirtual * m_virtualToWidget).map(image_line)
);
m_zoom *= widget_line_before.length() / widget_line_after.length();
updateWidgetTransform();
update();
}
void
ImageViewBase::ensureStatusTip(QString const& status_tip)
{
QString const cur_status_tip(statusTip());
if (cur_status_tip.constData() == status_tip.constData()) {
return;
}
if (cur_status_tip == status_tip) {
return;
}
viewport()->setStatusTip(status_tip);
if (viewport()->underMouse()) {
// Note that setStatusTip() alone is not enough,
// as it's only taken into account when the mouse
// enters the widget.
// Also note that we use postEvent() rather than sendEvent(),
// because sendEvent() may immediately process other events.
QApplication::postEvent(viewport(), new QStatusTipEvent(status_tip));
}
}
void
ImageViewBase::paintEvent(QPaintEvent* event)
{
QPainter painter(viewport());
painter.save();
// On X11 (except with OpenGL), SmoothPixmapTransform is too slow, so don't enable it.
bool smooth_pixmap_ok = true;
#if defined(Q_WS_X11)
smooth_pixmap_ok = viewport()->inherits("QGLWidget");
#endif
if (smooth_pixmap_ok) {
double const xscale = m_virtualToWidget.m11();
// Width of a source pixel in mm, as it's displayed on screen.
double const pixel_width = widthMM() * xscale / width();
// Disable antialiasing for large zoom levels.
painter.setRenderHint(QPainter::SmoothPixmapTransform, pixel_width < 0.5);
}
if (validateHqPixmap()) {
// HQ pixmap maps one to one to screen pixels, so antialiasing is not necessary.
painter.setRenderHint(QPainter::SmoothPixmapTransform, false);
painter.drawPixmap(m_hqPixmapPos, m_hqPixmap);
} else {
scheduleHqVersionRebuild();
painter.setWorldTransform(
m_pixmapToImage * m_imageToVirtual * m_virtualToWidget
);
PixmapRenderer::drawPixmap(painter, m_pixmap);
}
painter.setRenderHints(QPainter::Antialiasing, true);
painter.setWorldMatrixEnabled(false);
// Cover parts of the image that should not be visible with background.
// Note that because of Qt::WA_OpaquePaintEvent attribute, we need
// to paint the whole widget, which we do here.
QPolygonF const image_area(
PolygonUtils::round(
m_virtualToWidget.map(
m_imageToVirtual.map(QRectF(m_image.rect()))
)
)
);
QPolygonF const crop_area(
PolygonUtils::round(m_virtualToWidget.map(m_virtualImageCropArea))
);
QPolygonF const intersected_area(
PolygonUtils::round(image_area.intersected(crop_area))
);
QPainterPath intersected_path;
intersected_path.addPolygon(intersected_area);
QPainterPath containing_path;
containing_path.addRect(viewport()->rect());
QBrush const brush(palette().color(QPalette::Window));
QPen pen(brush, 1.0);
pen.setCosmetic(true);
// By using a pen with the same color as the brush, we essentially
// expanding the area we are going to draw. It's necessary because
// XRender doesn't provide subpixel accuracy.
painter.setPen(pen);
painter.setBrush(brush);
painter.drawPath(containing_path.subtracted(intersected_path));
painter.restore();
painter.setWorldTransform(m_virtualToWidget);
m_interactionState.resetProximity();
if (!m_interactionState.captured()) {
m_rootInteractionHandler.proximityUpdate(
QPointF(0.5, 0.5) + mapFromGlobal(QCursor::pos()), m_interactionState
);
updateStatusTipAndCursor();
}
m_rootInteractionHandler.paint(painter, m_interactionState);
maybeQueueRedraw();
}
void
ImageViewBase::keyPressEvent(QKeyEvent* event)
{
event->setAccepted(false);
m_rootInteractionHandler.keyPressEvent(event, m_interactionState);
event->setAccepted(true);
updateStatusTipAndCursor();
maybeQueueRedraw();
}
void
ImageViewBase::keyReleaseEvent(QKeyEvent* event)
{
event->setAccepted(false);
m_rootInteractionHandler.keyReleaseEvent(event, m_interactionState);
event->setAccepted(true);
updateStatusTipAndCursor();
maybeQueueRedraw();
}
void
ImageViewBase::mousePressEvent(QMouseEvent* event)
{
m_interactionState.resetProximity();
if (!m_interactionState.captured()) {
m_rootInteractionHandler.proximityUpdate(
QPointF(0.5, 0.5) + event->pos(), m_interactionState
);
}
event->setAccepted(false);
m_rootInteractionHandler.mousePressEvent(event, m_interactionState);
event->setAccepted(true);
updateStatusTipAndCursor();
void maybeQueueRedraw();
}
void
ImageViewBase::mouseReleaseEvent(QMouseEvent* event)
{
m_interactionState.resetProximity();
if (!m_interactionState.captured()) {
m_rootInteractionHandler.proximityUpdate(
QPointF(0.5, 0.5) + event->pos(), m_interactionState
);
}
event->setAccepted(false);
m_rootInteractionHandler.mouseReleaseEvent(event, m_interactionState);
event->setAccepted(true);
updateStatusTipAndCursor();
maybeQueueRedraw();
}
void
ImageViewBase::mouseMoveEvent(QMouseEvent* event)
{
m_interactionState.resetProximity();
if (!m_interactionState.captured()) {
m_rootInteractionHandler.proximityUpdate(
QPointF(0.5, 0.5) + event->pos(), m_interactionState
);
}
event->setAccepted(false);
m_rootInteractionHandler.mouseMoveEvent(event, m_interactionState);
event->setAccepted(true);
updateStatusTipAndCursor();
maybeQueueRedraw();
}
void
ImageViewBase::wheelEvent(QWheelEvent* event)
{
event->setAccepted(false);
m_rootInteractionHandler.wheelEvent(event, m_interactionState);
event->setAccepted(true);
updateStatusTipAndCursor();
maybeQueueRedraw();
}
void
ImageViewBase::contextMenuEvent(QContextMenuEvent* event)
{
event->setAccepted(false);
m_rootInteractionHandler.contextMenuEvent(event, m_interactionState);
event->setAccepted(true);
updateStatusTipAndCursor();
maybeQueueRedraw();
}
void
ImageViewBase::resizeEvent(QResizeEvent* event)
{
QAbstractScrollArea::resizeEvent(event);
if (m_ignoreResizeEvents) {
return;
}
ScopedIncDec<int> const guard(m_ignoreScrollEvents);
if (maximumViewportSize() != m_lastMaximumViewportSize) {
m_lastMaximumViewportSize = maximumViewportSize();
m_widgetFocalPoint = centeredWidgetFocalPoint();
updateWidgetTransform();
} else {
TransformChangeWatcher const watcher(*this);
TempFocalPointAdjuster const temp_fp(*this, QPointF(0, 0));
updateTransformPreservingScale(
ImagePresentation(m_imageToVirtual, m_virtualImageCropArea, m_virtualDisplayArea)
);
}
}
void
ImageViewBase::enterEvent(QEvent* event)
{
viewport()->setFocus();
QAbstractScrollArea::enterEvent(event);
}
/**
* Called when any of the transformations change.
*/
void
ImageViewBase::transformChanged()
{
updateScrollBars();
}
void
ImageViewBase::updateScrollBars()
{
if (verticalScrollBar()->isSliderDown() || horizontalScrollBar()->isSliderDown()) {
return;
}
ScopedIncDec<int> const guard1(m_ignoreScrollEvents);
ScopedIncDec<int> const guard2(m_ignoreResizeEvents);
QRectF const picture(m_virtualToWidget.mapRect(virtualDisplayRect()));
QPointF const viewport_center(maxViewportRect().center());
QPointF const picture_center(picture.center());
QRectF viewport(maxViewportRect());
// Introduction of one scrollbar will decrease the available size in
// another direction, which may cause a scrollbar in that direction
// to become necessary. For this reason, we have a loop here.
for (int i = 0; i < 2; ++i) {
double const xval = picture_center.x();
double xmin, xmax; // Minimum and maximum positions for picture center.
if (picture_center.x() < viewport_center.x()) {
xmin = std::min<double>(xval, viewport.right() - 0.5 * picture.width());
xmax = std::max<double>(viewport_center.x(), viewport.left() + 0.5 * picture.width());
} else {
xmax = std::max<double>(xval, viewport.left() + 0.5 * picture.width());
xmin = std::min<double>(viewport_center.x(), viewport.right() - 0.5 * picture.width());
}
double const yval = picture_center.y();
double ymin, ymax; // Minimum and maximum positions for picture center.
if (picture_center.y() < viewport_center.y()) {
ymin = std::min<double>(yval, viewport.bottom() - 0.5 * picture.height());
ymax = std::max<double>(viewport_center.y(), viewport.top() + 0.5 * picture.height());
} else {
ymax = std::max<double>(yval, viewport.top() + 0.5 * picture.height());
ymin = std::min<double>(viewport_center.y(), viewport.bottom() - 0.5 * picture.height());
}
int const xrange = (int)ceil(xmax - xmin);
int const yrange = (int)ceil(ymax - ymin);
int const xfirst = 0;
int const xlast = xrange - 1;
int const yfirst = 0;
int const ylast = yrange - 1;
// We are going to map scrollbar coordinates to widget coordinates
// of the central point of the display area using a linear function.
// f(x) = ax + b
// xmin = xa * xlast + xb
// xmax = xa * xfirst + xb
double const xa = (xfirst == xlast) ? 1 : (xmax - xmin) / (xfirst - xlast);
double const xb = xmax - xa * xfirst;
double const ya = (yfirst == ylast) ? 1 : (ymax - ymin) / (yfirst - ylast);
double const yb = ymax - ya * yfirst;
// Inverse transformation.
// xlast = ixa * xmin + ixb
// xfirst = ixa * xmax + ixb
double const ixa = (xmax == xmin) ? 1 : (xfirst - xlast) / (xmax - xmin);
double const ixb = xfirst - ixa * xmax;
double const iya = (ymax == ymin) ? 1 : (yfirst - ylast) / (ymax - ymin);
double const iyb = yfirst - iya * ymax;
m_scrollTransform.setMatrix(xa, 0, 0, 0, ya, 0, xb, yb, 1);
int const xcur = qRound(ixa * xval + ixb);
int const ycur = qRound(iya * yval + iyb);
horizontalScrollBar()->setRange(xfirst, xlast);
verticalScrollBar()->setRange(yfirst, ylast);
horizontalScrollBar()->setValue(xcur);
verticalScrollBar()->setValue(ycur);
horizontalScrollBar()->setPageStep(qRound(viewport.width()));
verticalScrollBar()->setPageStep(qRound(viewport.height()));
// XXX: a hack to force immediate update of viewport()->rect(),
// which is used by dynamicViewportRect() below.
// Note that it involves a resize event being sent not only to
// the viewport, but for some reason also to the containing
// QAbstractScrollArea, that is to this object.
setHorizontalScrollBarPolicy(horizontalScrollBarPolicy());
QRectF const old_viewport(viewport);
viewport = dynamicViewportRect();
if (viewport == old_viewport) {
break;
}
}
}
void
ImageViewBase::reactToScrollBars()
{
if (m_ignoreScrollEvents) {
return;
}
TransformChangeWatcher const watcher(*this);
QPointF const raw_position(
horizontalScrollBar()->value(), verticalScrollBar()->value()
);
QPointF const new_fp(m_scrollTransform.map(raw_position));
QPointF const old_fp(getWidgetFocalPoint());
m_pixmapFocalPoint = m_virtualToImage.map(m_virtualDisplayArea.center());
m_widgetFocalPoint = new_fp;
updateWidgetTransform();
setWidgetFocalPointWithoutMoving(old_fp);
}
/**
* Updates m_virtualToWidget and m_widgetToVirtual.\n
* To be called whenever any of the following is modified:
* m_imageToVirt, m_widgetFocalPoint, m_pixmapFocalPoint, m_zoom.
* Modifying both m_widgetFocalPoint and m_pixmapFocalPoint in a way
* that doesn't cause image movement doesn't require calling this method.
*/
void
ImageViewBase::updateWidgetTransform()
{
TransformChangeWatcher const watcher(*this);
QRectF const virt_rect(virtualDisplayRect());
QPointF const virt_origin(m_imageToVirtual.map(m_pixmapFocalPoint));
QPointF const widget_origin(m_widgetFocalPoint);
QSizeF zoom1_widget_size(virt_rect.size());
zoom1_widget_size.scale(maxViewportRect().size(), Qt::KeepAspectRatio);
double const zoom1_x = zoom1_widget_size.width() / virt_rect.width();
double const zoom1_y = zoom1_widget_size.height() / virt_rect.height();
QTransform xform;
xform.translate(-virt_origin.x(), -virt_origin.y());
xform *= QTransform().scale(zoom1_x * m_zoom, zoom1_y * m_zoom);
xform *= QTransform().translate(widget_origin.x(), widget_origin.y());
m_virtualToWidget = xform;
m_widgetToVirtual = m_virtualToWidget.inverted();
}
/**
* Updates m_virtualToWidget and m_widgetToVirtual and adjusts
* the focal point if necessary.\n
* To be called whenever m_imageToVirt is modified in such a way that
* may invalidate the focal point.
*/
void
ImageViewBase::updateWidgetTransformAndFixFocalPoint(FocalPointMode const mode)
{
TransformChangeWatcher const watcher(*this);
// This must go before getIdealWidgetFocalPoint(), as it
// recalculates m_virtualToWidget, that is used by
// getIdealWidgetFocalPoint().
updateWidgetTransform();
QPointF const ideal_widget_fp(getIdealWidgetFocalPoint(mode));
if (ideal_widget_fp != m_widgetFocalPoint) {
m_widgetFocalPoint = ideal_widget_fp;
updateWidgetTransform();
}
}
/**
* Returns a proposed value for m_widgetFocalPoint to minimize the
* unused widget space. Unused widget space indicates one or both
* of the following:
* \li The image is smaller than the display area.
* \li Parts of the image are outside of the display area.
*
* \param mode If set to CENTER_IF_FITS, then the returned focal point
* will center the image if it completely fits into the widget.
* This works in horizontal and vertical directions independently.\n
* If \p mode is set to DONT_CENTER and the image completely fits
* the widget, then the returned focal point will cause a minimal
* move to force the whole image to be visible.
*
* In case there is no unused widget space, the returned focal point
* is equal to the current focal point (m_widgetFocalPoint). This works
* in horizontal and vertical dimensions independently.
*/
QPointF
ImageViewBase::getIdealWidgetFocalPoint(FocalPointMode const mode) const
{
// Widget rect reduced by margins.
QRectF const display_area(maxViewportRect());
// The virtual image rectangle in widget coordinates.
QRectF const image_area(m_virtualToWidget.mapRect(virtualDisplayRect()));
// Unused display space from each side.
double const left_margin = image_area.left() - display_area.left();
double const right_margin = display_area.right() - image_area.right();
double const top_margin = image_area.top() - display_area.top();
double const bottom_margin = display_area.bottom() - image_area.bottom();
QPointF widget_focal_point(m_widgetFocalPoint);
if (mode == CENTER_IF_FITS && left_margin + right_margin >= 0.0) {
// Image fits horizontally, so center it in that direction
// by equalizing its left and right margins.
double const new_margins = 0.5 * (left_margin + right_margin);
widget_focal_point.rx() += new_margins - left_margin;
} else if (left_margin < 0.0 && right_margin > 0.0) {
// Move image to the right so that either left_margin or
// right_margin becomes zero, whichever requires less movement.
double const movement = std::min(fabs(left_margin), fabs(right_margin));
widget_focal_point.rx() += movement;
} else if (right_margin < 0.0 && left_margin > 0.0) {
// Move image to the left so that either left_margin or
// right_margin becomes zero, whichever requires less movement.
double const movement = std::min(fabs(left_margin), fabs(right_margin));
widget_focal_point.rx() -= movement;
}
if (mode == CENTER_IF_FITS && top_margin + bottom_margin >= 0.0) {
// Image fits vertically, so center it in that direction
// by equalizing its top and bottom margins.
double const new_margins = 0.5 * (top_margin + bottom_margin);
widget_focal_point.ry() += new_margins - top_margin;
} else if (top_margin < 0.0 && bottom_margin > 0.0) {
// Move image down so that either top_margin or bottom_margin
// becomes zero, whichever requires less movement.
double const movement = std::min(fabs(top_margin), fabs(bottom_margin));
widget_focal_point.ry() += movement;
} else if (bottom_margin < 0.0 && top_margin > 0.0) {
// Move image up so that either top_margin or bottom_margin
// becomes zero, whichever requires less movement.
double const movement = std::min(fabs(top_margin), fabs(bottom_margin));
widget_focal_point.ry() -= movement;
}
return widget_focal_point;
}
void
ImageViewBase::setNewWidgetFP(QPointF const widget_fp, bool const update)
{
if (widget_fp != m_widgetFocalPoint) {
m_widgetFocalPoint = widget_fp;
updateWidgetTransform();
if (update) {
this->update();
}
}
}
/**
* Used when dragging the image. It adjusts the movement to disallow
* dragging it away from the ideal position (determined by
* getIdealWidgetFocalPoint()). Movement towards the ideal position
* is permitted. This works independently in horizontal and vertical
* direction.
*
* \param proposed_widget_fp The proposed value for m_widgetFocalPoint.
* \param update Whether to call this->update() in case the focal point
* has changed.
*/
void
ImageViewBase::adjustAndSetNewWidgetFP(
QPointF const proposed_widget_fp, bool const update)
{
// We first apply the proposed focal point, and only then
// calculate the ideal one. That's done because
// the ideal focal point is the current focal point when
// no widget space is wasted (image covers the whole widget).
// We don't want the ideal focal point to be equal to the current
// one, as that would disallow any movements.
QPointF const old_widget_fp(m_widgetFocalPoint);
setNewWidgetFP(proposed_widget_fp, update);
QPointF const ideal_widget_fp(getIdealWidgetFocalPoint(CENTER_IF_FITS));
QPointF const towards_ideal(ideal_widget_fp - old_widget_fp);
QPointF const towards_proposed(proposed_widget_fp - old_widget_fp);
QPointF movement(towards_proposed);
// Horizontal movement.
if (towards_ideal.x() * towards_proposed.x() < 0.0) {
// Wrong direction - no movement at all.
movement.setX(0.0);
} else if (fabs(towards_proposed.x()) > fabs(towards_ideal.x())) {
// Too much movement - limit it.
movement.setX(towards_ideal.x());
}
// Vertical movement.
if (towards_ideal.y() * towards_proposed.y() < 0.0) {
// Wrong direction - no movement at all.
movement.setY(0.0);
} else if (fabs(towards_proposed.y()) > fabs(towards_ideal.y())) {
// Too much movement - limit it.
movement.setY(towards_ideal.y());
}
QPointF const adjusted_widget_fp(old_widget_fp + movement);
if (adjusted_widget_fp != m_widgetFocalPoint) {
m_widgetFocalPoint = adjusted_widget_fp;
updateWidgetTransform();
if (update) {
this->update();
}
}
}
/**
* Returns the center point of the available display area.
*/
QPointF
ImageViewBase::centeredWidgetFocalPoint() const
{
return maxViewportRect().center();
}
void
ImageViewBase::setWidgetFocalPointWithoutMoving(QPointF const new_widget_fp)
{
m_widgetFocalPoint = new_widget_fp;
m_pixmapFocalPoint = m_virtualToImage.map(
m_widgetToVirtual.map(m_widgetFocalPoint)
);
}
/**
* Returns true if m_hqPixmap is valid and up to date.
*/
bool
ImageViewBase::validateHqPixmap() const
{
if (!m_hqTransformEnabled) {
return false;
}
if (m_hqPixmap.isNull()) {
return false;
}
if (m_hqSourceId != m_image.cacheKey()) {
return false;
}
if (m_hqXform != m_imageToVirtual * m_virtualToWidget) {
return false;
}
return true;
}
void
ImageViewBase::scheduleHqVersionRebuild()
{
QTransform const xform(m_imageToVirtual * m_virtualToWidget);
if (!m_timer.isActive() || m_potentialHqXform != xform) {
if (m_ptrHqTransformTask.get()) {
m_ptrHqTransformTask->cancel();
m_ptrHqTransformTask.reset();
}
m_potentialHqXform = xform;
}
m_timer.start();
}
void
ImageViewBase::initiateBuildingHqVersion()
{
if (validateHqPixmap()) {
return;
}
m_hqPixmap = QPixmap();
if (m_ptrHqTransformTask.get()) {
m_ptrHqTransformTask->cancel();
m_ptrHqTransformTask.reset();
}
QTransform const xform(m_imageToVirtual * m_virtualToWidget);
IntrusivePtr<HqTransformTask> const task(
new HqTransformTask(this, m_image, xform, viewport()->size())
);
backgroundExecutor().enqueueTask(task);
m_ptrHqTransformTask = task;
m_hqXform = xform;
m_hqSourceId = m_image.cacheKey();
}
/**
* Gets called from HqTransformationTask::Result.
*/
void
ImageViewBase::hqVersionBuilt(
QPoint const& origin, QImage const& image)
{
if (!m_hqTransformEnabled) {
return;
}
m_hqPixmap = QPixmap::fromImage(image);
m_hqPixmapPos = origin;
m_ptrHqTransformTask.reset();
update();
}
void
ImageViewBase::updateStatusTipAndCursor()
{
updateStatusTip();
updateCursor();
}
void
ImageViewBase::updateStatusTip()
{
ensureStatusTip(m_interactionState.statusTip());
}
void
ImageViewBase::updateCursor()
{
viewport()->setCursor(m_interactionState.cursor());
}
void
ImageViewBase::maybeQueueRedraw()
{
if (m_interactionState.redrawRequested()) {
m_interactionState.setRedrawRequested(false);
update();
}
}
BackgroundExecutor&
ImageViewBase::backgroundExecutor()
{
static BackgroundExecutor executor;
return executor;
}
/*==================== ImageViewBase::HqTransformTask ======================*/
ImageViewBase::HqTransformTask::HqTransformTask(
ImageViewBase* image_view,
QImage const& image, QTransform const& xform,
QSize const& target_size)
: m_ptrResult(new Result(image_view)),
m_image(image),
m_xform(xform),
m_targetSize(target_size)
{
}
IntrusivePtr<AbstractCommand0<void> >
ImageViewBase::HqTransformTask::operator()()
{
if (isCancelled()) {
return IntrusivePtr<AbstractCommand0<void> >();
}
QRect const target_rect(
m_xform.map(
QRectF(m_image.rect())
).boundingRect().toRect().intersected(
QRect(QPoint(0, 0), m_targetSize)
)
);
QImage hq_image(
transform(
m_image, m_xform, target_rect,
OutsidePixels::assumeWeakColor(Qt::white), QSizeF(0.0, 0.0)
)
);
#if defined(Q_WS_X11)
// ARGB32_Premultiplied is an optimal format for X11 + XRender.
hq_image = hq_image.convertToFormat(QImage::Format_ARGB32_Premultiplied);
#endif
m_ptrResult->setData(target_rect.topLeft(), hq_image);
return m_ptrResult;
}
/*================ ImageViewBase::HqTransformTask::Result ================*/
ImageViewBase::HqTransformTask::Result::Result(
ImageViewBase* image_view)
: m_ptrImageView(image_view)
{
}
void
ImageViewBase::HqTransformTask::Result::setData(
QPoint const& origin, QImage const& hq_image)
{
m_hqImage = hq_image;
m_origin = origin;
}
void
ImageViewBase::HqTransformTask::Result::operator()()
{
if (m_ptrImageView && !isCancelled()) {
m_ptrImageView->hqVersionBuilt(m_origin, m_hqImage);
}
}
/*================= ImageViewBase::TempFocalPointAdjuster =================*/
ImageViewBase::TempFocalPointAdjuster::TempFocalPointAdjuster(ImageViewBase& obj)
: m_rObj(obj),
m_origWidgetFP(obj.getWidgetFocalPoint())
{
obj.setWidgetFocalPointWithoutMoving(obj.centeredWidgetFocalPoint());
}
ImageViewBase::TempFocalPointAdjuster::TempFocalPointAdjuster(
ImageViewBase& obj, QPointF const temp_widget_fp)
: m_rObj(obj),
m_origWidgetFP(obj.getWidgetFocalPoint())
{
obj.setWidgetFocalPointWithoutMoving(temp_widget_fp);
}
ImageViewBase::TempFocalPointAdjuster::~TempFocalPointAdjuster()
{
m_rObj.setWidgetFocalPointWithoutMoving(m_origWidgetFP);
}
/*================== ImageViewBase::TransformChangeWatcher ================*/
ImageViewBase::TransformChangeWatcher::TransformChangeWatcher(ImageViewBase& owner)
: m_rOwner(owner),
m_imageToVirtual(owner.m_imageToVirtual),
m_virtualToWidget(owner.m_virtualToWidget),
m_virtualDisplayArea(owner.m_virtualDisplayArea)
{
++m_rOwner.m_transformChangeWatchersActive;
}
ImageViewBase::TransformChangeWatcher::~TransformChangeWatcher()
{
if (--m_rOwner.m_transformChangeWatchersActive == 0) {
if (m_imageToVirtual != m_rOwner.m_imageToVirtual ||
m_virtualToWidget != m_rOwner.m_virtualToWidget ||
m_virtualDisplayArea != m_rOwner.m_virtualDisplayArea) {
m_rOwner.transformChanged();
}
}
}
|