1 files changed, 146 insertions, 0 deletions
diff --git a/src/gui/tikzview.cpp b/src/gui/tikzview.cpp
new file mode 100644
index 0000000..52a32cf
--- /dev/null
+++ b/src/gui/tikzview.cpp
@@ -0,0 +1,146 @@
+/*
+    TikZiT - a GUI diagram editor for TikZ
+    Copyright (C) 2018 Aleks Kissinger
+
+    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 <https://www.gnu.org/licenses/>.
+*/
+
+#include "tikzview.h"
+#include "tikzit.h"
+
+#include <QDebug>
+#include <QScrollBar>
+
+TikzView::TikzView(QWidget *parent) : QGraphicsView(parent)
+{
+    setRenderHint(QPainter::Antialiasing);
+    setResizeAnchor(QGraphicsView::AnchorViewCenter);
+    //setDragMode(QGraphicsView::RubberBandDrag);
+
+    setBackgroundBrush(QBrush(Qt::white));
+
+    _scale = 1.0f;
+}
+
+void TikzView::zoomIn()
+{
+    _scale *= 1.6f;
+    scale(1.6,1.6);
+}
+
+void TikzView::zoomOut()
+{
+    _scale *= 0.625f;
+    scale(0.625,0.625);
+}
+
+void TikzView::setScene(QGraphicsScene *scene)
+{
+    QGraphicsView::setScene(scene);
+    centerOn(QPointF(0.0f,0.0f));
+}
+
+void TikzView::drawBackground(QPainter *painter, const QRectF &rect)
+{
+    QGraphicsView::drawBackground(painter, rect);
+    // draw a gray background if disabled
+    TikzScene *sc = static_cast<TikzScene*>(scene());
+    if (!sc->enabled()) painter->fillRect(rect, QBrush(QColor(240,240,240)));
+
+    // draw the grid
+
+    QPen pen1;
+    //pen1.setWidthF(0.5);
+    pen1.setCosmetic(true);
+    pen1.setColor(QColor(250,250,255));
+
+    QPen pen2 = pen1;
+    pen2.setColor(QColor(240,240,250));
+
+    QPen pen3 = pen1;
+    pen3.setColor(QColor(220,220,240));
+
+    painter->setPen(pen1);
+
+    if (_scale > 0.2f) {
+        for (int x = -GRID_SEP; x > rect.left(); x -= GRID_SEP) {
+            if (x % (GRID_SEP * GRID_N) != 0) {
+                qreal xf = (qreal)x;
+                painter->drawLine(xf, rect.top(), xf, rect.bottom());
+            }
+        }
+
+        for (int x = GRID_SEP; x < rect.right(); x += GRID_SEP) {
+            if (x % (GRID_SEP * GRID_N) != 0) {
+                qreal xf = (qreal)x;
+                painter->drawLine(xf, rect.top(), xf, rect.bottom());
+            }
+        }
+
+        for (int y = -GRID_SEP; y > rect.top(); y -= GRID_SEP) {
+            if (y % (GRID_SEP * GRID_N) != 0) {
+                qreal yf = (qreal)y;
+                painter->drawLine(rect.left(), yf, rect.right(), yf);
+            }
+        }
+
+        for (int y = GRID_SEP; y < rect.bottom(); y += GRID_SEP) {
+            if (y % (GRID_SEP * GRID_N) != 0) {
+                qreal yf = (qreal)y;
+                painter->drawLine(rect.left(), yf, rect.right(), yf);
+            }
+        }
+    }
+
+    painter->setPen(pen2);
+
+    for (int x = -GRID_SEP*GRID_N; x > rect.left(); x -= GRID_SEP*GRID_N) {
+        qreal xf = (qreal)x;
+        painter->drawLine(xf, rect.top(), xf, rect.bottom());
+    }
+
+    for (int x = GRID_SEP*GRID_N; x < rect.right(); x += GRID_SEP*GRID_N) {
+        qreal xf = (qreal)x;
+        painter->drawLine(xf, rect.top(), xf, rect.bottom());
+    }
+
+    for (int y = -GRID_SEP*GRID_N; y > rect.top(); y -= GRID_SEP*GRID_N) {
+        qreal yf = (qreal)y;
+        painter->drawLine(rect.left(), yf, rect.right(), yf);
+    }
+
+    for (int y = GRID_SEP*GRID_N; y < rect.bottom(); y += GRID_SEP*GRID_N) {
+        qreal yf = (qreal)y;
+        painter->drawLine(rect.left(), yf, rect.right(), yf);
+    }
+
+    painter->setPen(pen3);
+    painter->drawLine(rect.left(), 0, rect.right(), 0);
+    painter->drawLine(0, rect.top(), 0, rect.bottom());
+}
+
+void TikzView::wheelEvent(QWheelEvent *event)
+{
+    if (event->modifiers() & Qt::ShiftModifier) {
+        event->setModifiers(Qt::NoModifier);
+        QGraphicsView::wheelEvent(event);
+    } else if (event->modifiers() & Qt::ControlModifier) {
+        if (event->angleDelta().y() > 0) {
+            zoomIn();
+        } else if (event->angleDelta().y() < 0) {
+            zoomOut();
+        }
+    }
+}
+