src/gldraw.cpp

/*
 *  LDForge: LDraw parts authoring CAD
 *  Copyright (C) 2013 Santeri Piippo
 *
 *  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 <QGLWidget>
#include <QWheelEvent>
#include <QMouseEvent>
#include <QContextMenuEvent>
#include <QInputDialog>
#include <QToolTip>
#include <QTimer>
#include <GL/glu.h>

#include "common.h"
#include "config.h"
#include "file.h"
#include "gldraw.h"
#include "colors.h"
#include "gui.h"
#include "misc.h"
#include "history.h"
#include "dialogs.h"
#include "addObjectDialog.h"
#include "messagelog.h"
#include "moc_gldraw.cpp"

static const LDFixedCameraInfo g_FixedCameras[6] =
{	{{  1,  0, 0 }, X, Z, false, false },
	{{  0,  0, 0 }, X, Y, false,  true },
	{{  0,  1, 0 }, Z, Y,  true,  true },
	{{ -1,  0, 0 }, X, Z, false,  true },
	{{  0,  0, 0 }, X, Y,  true,  true },
	{{  0, -1, 0 }, Z, Y, false,  true },
};

static const matrix g_circleDrawTransforms[3] =
{	{ 2, 0, 0, 0, 1, 0, 0, 0, 2 },
	{ 2, 0, 0, 0, 0, 2, 0, 1, 0 },
	{ 0, 1, 0, 2, 0, 0, 0, 0, 2 },
};

cfg (String, gl_bgcolor, "#CCCCD9");
cfg (String, gl_maincolor, "#707078");
cfg (Float, gl_maincolor_alpha, 1.0);
cfg (Int, gl_linethickness, 2);
cfg (Bool, gl_colorbfc, false);
cfg (Int, gl_camera, GLRenderer::Free);
cfg (Bool, gl_blackedges, false);
cfg (Bool, gl_axes, false);
cfg (Bool, gl_wireframe, false);
cfg (Bool, gl_logostuds, false);

// argh
const char* g_CameraNames[7] =
{	QT_TRANSLATE_NOOP ("GLRenderer",  "Top"),
	QT_TRANSLATE_NOOP ("GLRenderer",  "Front"),
	QT_TRANSLATE_NOOP ("GLRenderer",  "Left"),
	QT_TRANSLATE_NOOP ("GLRenderer",  "Bottom"),
	QT_TRANSLATE_NOOP ("GLRenderer",  "Back"),
	QT_TRANSLATE_NOOP ("GLRenderer",  "Right"),
	QT_TRANSLATE_NOOP ("GLRenderer",  "Free")
};

const GL::Camera g_Cameras[7] =
{	GL::Top,
	GL::Front,
	GL::Left,
	GL::Bottom,
	GL::Back,
	GL::Right,
	GL::Free
};

const struct LDGLAxis
{	const QColor col;
	const vertex vert;
} g_GLAxes[3] =
{	{ QColor (255,   0,   0), vertex (10000, 0, 0) },
	{ QColor (80,  192,   0), vertex (0, 10000, 0) },
	{ QColor (0,   160, 192), vertex (0, 0, 10000) },
};

static bool g_glInvert = false;
static List<short> g_warnedColors;

// =============================================================================
// -----------------------------------------------------------------------------
GLRenderer::GLRenderer (QWidget* parent) : QGLWidget (parent)
{	m_picking = m_rangepick = false;
	m_camera = (GL::Camera) gl_camera.value;
	m_drawToolTip = false;
	m_editMode = Select;
	m_rectdraw = false;
	m_panning = false;
	setFile (null);
	setDrawOnly (false);
	resetAngles();
	setMessageLog (null);

	m_toolTipTimer = new QTimer (this);
	m_toolTipTimer->setSingleShot (true);
	connect (m_toolTipTimer, SIGNAL (timeout()), this, SLOT (slot_toolTipTimer()));

	m_thickBorderPen = QPen (QColor (0, 0, 0, 208), 2, Qt::SolidLine, Qt::RoundCap, Qt::RoundJoin);
	m_thinBorderPen = m_thickBorderPen;
	m_thinBorderPen.setWidth (1);

	// Init camera icons
	for (const GL::Camera cam : g_Cameras)
	{	str iconname = fmt ("camera-%1", tr (g_CameraNames[cam]).toLower());

		CameraIcon* info = &m_cameraIcons[cam];
		info->img = new QPixmap (getIcon (iconname));
		info->cam = cam;
	}

	for (int i = 0; i < 6; ++i)
	{	m_overlays[i].img = null;
		m_depthValues[i] = 0.0f;
	}

	calcCameraIcons();
}

// =============================================================================
// -----------------------------------------------------------------------------
GLRenderer::~GLRenderer()
{	for (int i = 0; i < 6; ++i)
		delete m_overlays[i].img;

	for (CameraIcon& info : m_cameraIcons)
		delete info.img;
}

// =============================================================================
// Calculates the "hitboxes" of the camera icons so that we can tell when the
// cursor is pointing at the camera icon.
// -----------------------------------------------------------------------------
void GLRenderer::calcCameraIcons()
{	int i = 0;

	for (CameraIcon& info : m_cameraIcons)
	{	// MATH
		const long x1 = (m_width - (info.cam != Free ? 48 : 16)) + ((i % 3) * 16) - 1,
			y1 = ((i / 3) * 16) + 1;

		info.srcRect = QRect (0, 0, 16, 16);
		info.destRect = QRect (x1, y1, 16, 16);
		info.selRect = QRect (
			info.destRect.x(),
			info.destRect.y(),
			info.destRect.width() + 1,
			info.destRect.height() + 1
		);

		++i;
	}
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::initGLData()
{	glEnable (GL_BLEND);
	glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
	glEnable (GL_POLYGON_OFFSET_FILL);
	glPolygonOffset (1.0f, 1.0f);

	glEnable (GL_DEPTH_TEST);
	glShadeModel (GL_SMOOTH);
	glEnable (GL_MULTISAMPLE);

	glEnable (GL_LINE_SMOOTH);
	glHint (GL_LINE_SMOOTH_HINT, GL_NICEST);
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::resetAngles()
{	m_rotX = 30.0f;
	m_rotY = 325.f;
	m_panX = m_panY = m_rotZ = 0.0f;
	zoomToFit();
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::initializeGL()
{	setBackground();

	glLineWidth (gl_linethickness);

	setAutoFillBackground (false);
	setMouseTracking (true);
	setFocusPolicy (Qt::WheelFocus);
	compileAllObjects();
}

// =============================================================================
// -----------------------------------------------------------------------------
QColor GLRenderer::getMainColor()
{	QColor col (gl_maincolor);

	if (!col.isValid())
		return QColor (0, 0, 0);

	col.setAlpha (gl_maincolor_alpha * 255.f);
	return col;
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::setBackground()
{	QColor col (gl_bgcolor);

	if (!col.isValid())
		return;

	col.setAlpha (255);

	m_darkbg = luma (col) < 80;
	m_bgcolor = col;
	qglClearColor (col);
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::setObjectColor (LDObject* obj, const ListType list)
{	QColor qcol;

	if (!obj->isColored())
		return;

	if (list == GL::PickList)
	{	// Make the color by the object's ID if we're picking, so we can make the
		// ID again from the color we get from the picking results. Be sure to use
		// the top level parent's index since we want a subfile's children point
		// to the subfile itself.
		long i = obj->topLevelParent()->id();

		// Calculate a color based from this index. This method caters for
		// 16777216 objects. I don't think that'll be exceeded anytime soon. :)
		// ATM biggest is 53588.dat with 12600 lines.
		double r = (i / (256 * 256)) % 256,
			   g = (i / 256) % 256,
			   b = i % 256;

		qglColor (QColor (r, g, b));
		return;
	}

	if ( (list == BFCFrontList || list == BFCBackList) &&
			obj->getType() != LDObject::Line &&
			obj->getType() != LDObject::CndLine)
	{

		if (list == GL::BFCFrontList)
			qcol = QColor (40, 192, 0);
		else
			qcol = QColor (224, 0, 0);
	}
	else
	{	if (obj->color() == maincolor)
			qcol = getMainColor();
		else
		{	LDColor* col = getColor (obj->color());

			if (col)
				qcol = col->faceColor;
		}

		if (obj->color() == edgecolor)
		{	qcol = luma (m_bgcolor) < 40 ? QColor (64, 64, 64) : Qt::black;
			LDColor* col;

			if (!gl_blackedges && obj->parent() && (col = getColor (obj->parent()->color())))
				qcol = col->edgeColor;
		}

		if (qcol.isValid() == false)
		{	// The color was unknown. Use main color to make the object at least
			// not appear pitch-black.
			if (obj->color() != edgecolor)
				qcol = getMainColor();

			// Warn about the unknown colors, but only once.
			for (short i : g_warnedColors)
				if (obj->color() == i)
					return;

			print ("%1: Unknown color %2!\n", __func__, obj->color());
			g_warnedColors << obj->color();
			return;
		}
	}

	long r = qcol.red(),
		 g = qcol.green(),
		 b = qcol.blue(),
		 a = qcol.alpha();

	if (obj->topLevelParent()->selected())
	{	// Brighten it up for the select list.
		const uchar add = 51;

		r = min (r + add, 255l);
		g = min (g + add, 255l);
		b = min (b + add, 255l);
	}

	glColor4f (
		((double) r) / 255.0f,
		((double) g) / 255.0f,
		((double) b) / 255.0f,
		((double) a) / 255.0f);
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::refresh()
{	update();
	swapBuffers();
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::hardRefresh()
{	compileAllObjects();
	refresh();

	glLineWidth (gl_linethickness);
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::resizeGL (int w, int h)
{	m_width = w;
	m_height = h;

	calcCameraIcons();

	glViewport (0, 0, w, h);
	glMatrixMode (GL_PROJECTION);
	glLoadIdentity();
	gluPerspective (45.0f, (double) w / (double) h, 1.0f, 10000.0f);
	glMatrixMode (GL_MODELVIEW);
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::drawGLScene()
{	if (file() == null)
		return;

	if (gl_wireframe && !picking())
		glPolygonMode (GL_FRONT_AND_BACK, GL_LINE);

	glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	glEnable (GL_DEPTH_TEST);

	if (m_camera != Free)
	{	glMatrixMode (GL_PROJECTION);
		glPushMatrix();

		glLoadIdentity();
		glOrtho (-m_virtWidth, m_virtWidth, -m_virtHeight, m_virtHeight, -100.0f, 100.0f);
		glTranslatef (m_panX, m_panY, 0.0f);

		if (m_camera != Front && m_camera != Back)
		{	glRotatef (90.0f, g_FixedCameras[m_camera].glrotate[0],
					   g_FixedCameras[m_camera].glrotate[1],
					   g_FixedCameras[m_camera].glrotate[2]);
		}

		// Back camera needs to be handled differently
		if (m_camera == GLRenderer::Back)
		{	glRotatef (180.0f, 1.0f, 0.0f, 0.0f);
			glRotatef (180.0f, 0.0f, 0.0f, 1.0f);
		}
	}
	else
	{	glMatrixMode (GL_MODELVIEW);
		glPushMatrix();
		glLoadIdentity();

		glTranslatef (0.0f, 0.0f, -2.0f);
		glTranslatef (m_panX, m_panY, -zoom());
		glRotatef (m_rotX, 1.0f, 0.0f, 0.0f);
		glRotatef (m_rotY, 0.0f, 1.0f, 0.0f);
		glRotatef (m_rotZ, 0.0f, 0.0f, 1.0f);
	}

	const GL::ListType list = (!drawOnly() && m_picking) ? PickList : NormalList;

	if (gl_colorbfc && !m_picking && !drawOnly())
	{	glEnable (GL_CULL_FACE);

		for (LDObject* obj : file()->objects())
		{	if (obj->hidden())
				continue;

			glCullFace (GL_BACK);
			glCallList (obj->glLists[BFCFrontList]);

			glCullFace (GL_FRONT);
			glCallList (obj->glLists[BFCBackList]);
		}

		glDisable (GL_CULL_FACE);
	}
	else
	{	for (LDObject* obj : file()->objects())
		{	if (obj->hidden())
				continue;

			glCallList (obj->glLists[list]);
		}
	}

	if (gl_axes && !m_picking && !drawOnly())
		glCallList (m_axeslist);

	glPopMatrix();
	glMatrixMode (GL_MODELVIEW);
	glPolygonMode (GL_FRONT_AND_BACK, GL_FILL);
}

// =============================================================================
// -----------------------------------------------------------------------------
// This converts a 2D point on the screen to a 3D point in the model. If 'snap'
// is true, the 3D point will snap to the current grid.
// -----------------------------------------------------------------------------
vertex GLRenderer::coordconv2_3 (const QPoint& pos2d, bool snap) const
{	assert (camera() != Free);

	vertex pos3d;
	const LDFixedCameraInfo* cam = &g_FixedCameras[m_camera];
	const Axis axisX = cam->axisX;
	const Axis axisY = cam->axisY;
	const short negXFac = cam->negX ? -1 : 1,
				negYFac = cam->negY ? -1 : 1;

	// Calculate cx and cy - these are the LDraw unit coords the cursor is at.
	double cx = (-m_virtWidth + ( (2 * pos2d.x() * m_virtWidth) / m_width) - m_panX);
	double cy = (m_virtHeight - ( (2 * pos2d.y() * m_virtHeight) / m_height) - m_panY);

	if (snap)
	{	cx = Grid::snap (cx, (Grid::Config) axisX);
		cy = Grid::snap (cy, (Grid::Config) axisY);
	}

	cx *= negXFac;
	cy *= negYFac;

	str tmp;
	// Create the vertex from the coordinates
	pos3d[axisX] = tmp.sprintf ("%.3f", cx).toDouble();
	pos3d[axisY] = tmp.sprintf ("%.3f", cy).toDouble();
	pos3d[3 - axisX - axisY] = depthValue();
	return pos3d;
}

// =============================================================================
// -----------------------------------------------------------------------------
// Inverse operation for the above - convert a 3D position to a 2D screen
// position
// -----------------------------------------------------------------------------
QPoint GLRenderer::coordconv3_2 (const vertex& pos3d) const
{	GLfloat m[16];
	const LDFixedCameraInfo* cam = &g_FixedCameras[m_camera];
	const Axis axisX = cam->axisX;
	const Axis axisY = cam->axisY;
	const short negXFac = cam->negX ? -1 : 1,
				negYFac = cam->negY ? -1 : 1;

	glGetFloatv (GL_MODELVIEW_MATRIX, m);

	const double x = pos3d.x();
	const double y = pos3d.y();
	const double z = pos3d.z();

	vertex transformed;
	transformed[X] = (m[0] * x) + (m[1] * y) + (m[2] * z) + m[3];
	transformed[Y] = (m[4] * x) + (m[5] * y) + (m[6] * z) + m[7];
	transformed[Z] = (m[8] * x) + (m[9] * y) + (m[10] * z) + m[11];

	double rx = ( ( (transformed[axisX] * negXFac) + m_virtWidth + m_panX) * m_width) / (2 * m_virtWidth);
	double ry = ( ( (transformed[axisY] * negYFac) - m_virtHeight + m_panY) * m_height) / (2 * m_virtHeight);

	return QPoint (rx, -ry);
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::paintEvent (QPaintEvent* ev)
{	Q_UNUSED (ev)

	makeCurrent();
	m_virtWidth = zoom();
	m_virtHeight = (m_height * m_virtWidth) / m_width;

	initGLData();
	drawGLScene();

	const QPen textpen = getTextPen();
	const QBrush polybrush (QColor (64, 192, 0, 128));
	QPainter paint (this);
	QFontMetrics metrics = QFontMetrics (QFont());
	paint.setRenderHint (QPainter::HighQualityAntialiasing);

	// If we wish to only draw the brick, stop here
	if (drawOnly())
		return;

	if (m_camera != Free && !picking())
	{	// Paint the overlay image if we have one
		const LDGLOverlay& overlay = m_overlays[m_camera];

		if (overlay.img != null)
		{	QPoint v0 = coordconv3_2 (m_overlays[m_camera].v0),
					   v1 = coordconv3_2 (m_overlays[m_camera].v1);

			QRect targRect (v0.x(), v0.y(), abs (v1.x() - v0.x()), abs (v1.y() - v0.y())),
				  srcRect (0, 0, overlay.img->width(), overlay.img->height());
			paint.drawImage (targRect, *overlay.img, srcRect);
		}

		// Paint the coordinates onto the screen.
		str text = fmt (tr ("X: %1, Y: %2, Z: %3"), m_hoverpos[X], m_hoverpos[Y], m_hoverpos[Z]);

		QFontMetrics metrics = QFontMetrics (font());
		QRect textSize = metrics.boundingRect (0, 0, m_width, m_height, Qt::AlignCenter, text);

		paint.setPen (getTextPen());
		paint.drawText (m_width - textSize.width(), m_height - 16, textSize.width(),
			textSize.height(), Qt::AlignCenter, text);

		QPen linepen = m_thinBorderPen;
		linepen.setWidth (2);
		linepen.setColor (luma (m_bgcolor) < 40 ? Qt::white : Qt::black);

		// If we're drawing, draw the vertices onto the screen.
		if (editMode() == Draw)
		{	int numverts = 4;

			if (!m_rectdraw)
				numverts = m_drawedVerts.size() + 1;

			if (numverts > 0)
			{	QPoint poly[4];
				vertex polyverts[4];

				if (!m_rectdraw)
				{	uchar i = 0;

				for (vertex & vert : m_drawedVerts)
					{	poly[i] = coordconv3_2 (vert);
						polyverts[i] = vert;
						++i;
					}

					// Draw the cursor vertex as the last one in the list.
					if (numverts <= 4)
					{	poly[i] = coordconv3_2 (m_hoverpos);
						polyverts[i] = m_hoverpos;
					}
					else
					{	numverts = 4;
					}
				}
				else
				{	if (m_drawedVerts.size() > 0)
					{	// Get vertex information from m_rectverts
						for (int i = 0; i < numverts; ++i)
						{	polyverts[i] = m_rectverts[i];
							poly[i] = coordconv3_2 (polyverts[i]);
						}
					}
					else
					{	poly[0] = coordconv3_2 (m_hoverpos);
						polyverts[0] = m_hoverpos;
					}
				}

				// Draw the polygon-to-be
				paint.setPen (linepen);
				paint.setBrush (polybrush);
				paint.drawPolygon (poly, numverts);

				// Draw vertex blips
				for (int i = 0; i < numverts; ++i)
				{	QPoint& blip = poly[i];
					drawBlip (paint, blip);

					// Draw their coordinates
					paint.drawText (blip.x(), blip.y() - 8, polyverts[i].stringRep (true));
				}
			}
		}
		elif (editMode() == CircleMode)
		{	// If we have not specified the center point of the circle yet, preview it on the screen.
			if (m_drawedVerts.size() == 0)
				drawBlip (paint, coordconv3_2 (m_hoverpos));
			else
			{	QVector<vertex> verts, verts2;
				const double dist0 = circleDrawDist(0),
					dist1 = (m_drawedVerts.size() >= 2) ? circleDrawDist (1) : -1;
				const int segs = lores;
				const double angleUnit = (2 * pi) / segs;
				Axis relX, relY;
				QVector<QPoint> points,
					points2;

				getRelativeAxes (relX, relY);

				for (int i = 0; i < segs; ++i)
				{	vertex v = g_origin;
					v[relX] = m_drawedVerts[0][relX] + (cos (i * angleUnit) * dist0);
					v[relY] = m_drawedVerts[0][relY] + (sin (i * angleUnit) * dist0);
					verts << v;

					if (dist1 != -1)
					{	v[relX] = m_drawedVerts[0][relX] + (cos (i * angleUnit) * dist1);
						v[relY] = m_drawedVerts[0][relY] + (sin (i * angleUnit) * dist1);
						verts2 << v;
					}
				}

				for (const vertex& v : verts + verts2)
				{	QPoint point = coordconv3_2 (v);
					drawBlip (paint, point);
					points << point;
				}

				// Insert the first point as the seventeenth one so that
				// the ring polygon is closed properly.
				if (points.size() >= 16)
					points.insert (16, points[0]);

				// Same for the outer ring. Note that the indices are offset by 1
				// because of the insertion done above bumps the values.
				if (points.size() >= 33)
					points.insert (33, points[17]);

				{ // Draw the current radius in the middle of the circle.
					QPoint origin = coordconv3_2 (m_drawedVerts[0]);
					str label = str::number (dist0);
					paint.setPen (textpen);
					paint.drawText (origin.x() - (metrics.width (label) / 2), origin.y(), label);

					if (m_drawedVerts.size() >= 2)
					{	label = str::number (dist1);
						paint.drawText (origin.x() - (metrics.width (label) / 2), origin.y() + metrics.height(), label);
					}
				}

				// Draw the circle/ring
				paint.setPen (linepen);
				paint.setBrush ((m_drawedVerts.size() >= 2) ? polybrush : Qt::NoBrush);
				paint.drawPolygon (QPolygon (points));
			}
		}
	}

	// Camera icons
	if (!m_picking)
	{	// Draw a background for the selected camera
		paint.setPen (m_thinBorderPen);
		paint.setBrush (QBrush (QColor (0, 128, 160, 128)));
		paint.drawRect (m_cameraIcons[camera()].selRect);

		// Draw the actual icons
		for (CameraIcon& info : m_cameraIcons)
		{	// Don't draw the free camera icon when in draw mode
			if (&info == &m_cameraIcons[GL::Free] && editMode() != Select)
				continue;

			paint.drawPixmap (info.destRect, *info.img, info.srcRect);
		}

		str fmtstr = tr ("%1 Camera");

		// Draw a label for the current camera in the bottom left corner
		{	const int margin = 4;

			str label;
			label = fmt (fmtstr, tr (g_CameraNames[camera()]));
			paint.setPen (textpen);
			paint.drawText (QPoint (margin, height() - (margin + metrics.descent())), label);
		}

		// Tool tips
		if (m_drawToolTip)
		{	if (m_cameraIcons[m_toolTipCamera].destRect.contains (m_pos) == false)
				m_drawToolTip = false;
			else
			{	str label = fmt (fmtstr, tr (g_CameraNames[m_toolTipCamera]));
				QToolTip::showText (m_globalpos, label);
			}
		}
	}

	// Message log
	if (msglog())
	{	int y = 0;
		const int margin = 2;
		QColor penColor = getTextPen();

		for (const MessageManager::Line& line : msglog()->getLines())
		{	penColor.setAlphaF (line.alpha);
			paint.setPen (penColor);
			paint.drawText (QPoint (margin, y + margin + metrics.ascent()), line.text);
			y += metrics.height();
		}
	}

	// If we're range-picking, draw a rectangle encompassing the selection area.
	if (m_rangepick && !m_picking && m_totalmove >= 10)
	{	int x0 = m_rangeStart.x(),
			y0 = m_rangeStart.y(),
			x1 = m_pos.x(),
			y1 = m_pos.y();

		QRect rect (x0, y0, x1 - x0, y1 - y0);
		QColor fillColor = (m_addpick ? "#40FF00" : "#00CCFF");
		fillColor.setAlphaF (0.2f);

		paint.setPen (m_thickBorderPen);
		paint.setBrush (QBrush (fillColor));
		paint.drawRect (rect);
	}
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::drawBlip (QPainter& paint, QPoint pos) const
{	QPen pen = m_thinBorderPen;
	const int blipsize = 8;
	pen.setWidth (1);
	paint.setPen (pen);
	paint.setBrush (QColor (64, 192, 0));
	paint.drawEllipse (pos.x() - blipsize / 2, pos.y() - blipsize / 2, blipsize, blipsize);
}

// =============================================================================
// -----------------------------------------------------------------------------
QColor GLRenderer::getTextPen () const
{	return m_darkbg ? Qt::white : Qt::black;
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::compileAllObjects()
{	if (!file())
		return;

	// Compiling all is a big job, use a busy cursor
	setCursor (Qt::BusyCursor);

	m_knownVerts.clear();

for (LDObject * obj : file()->objects())
		compileObject (obj);

	// Compile axes
	glDeleteLists (m_axeslist, 1);
	m_axeslist = glGenLists (1);
	glNewList (m_axeslist, GL_COMPILE);
	glBegin (GL_LINES);

for (const LDGLAxis & ax : g_GLAxes)
	{	qglColor (ax.col);
		compileVertex (ax.vert);
		compileVertex (-ax.vert);
	}

	glEnd();
	glEndList();

	setCursor (Qt::ArrowCursor);
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::compileSubObject (LDObject* obj, const GLenum gltype)
{	glBegin (gltype);

	const short numverts = (obj->getType() != LDObject::CndLine) ? obj->vertices() : 2;

	if (g_glInvert == false)
		for (short i = 0; i < numverts; ++i)
			compileVertex (obj->m_coords[i]);
	else
		for (short i = numverts - 1; i >= 0; --i)
			compileVertex (obj->m_coords[i]);

	glEnd();
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::compileList (LDObject* obj, const GLRenderer::ListType list)
{	setObjectColor (obj, list);

	switch (obj->getType())
	{	case LDObject::Line:
			compileSubObject (obj, GL_LINES);
			break;

		case LDObject::CndLine:

			// Draw conditional lines with a dash pattern - however, use a full
			// line when drawing a pick list to make selecting them easier.
			if (list != GL::PickList)
			{	glLineStipple (1, 0x6666);
				glEnable (GL_LINE_STIPPLE);
			}

			compileSubObject (obj, GL_LINES);

			glDisable (GL_LINE_STIPPLE);
			break;

		case LDObject::Triangle:
			compileSubObject (obj, GL_TRIANGLES);
			break;

		case LDObject::Quad:
			compileSubObject (obj, GL_QUADS);
			break;

		case LDObject::Subfile:
		{	LDSubfile* ref = static_cast<LDSubfile*> (obj);
			List<LDObject*> objs;

			objs = ref->inlineContents (
					   LDSubfile::DeepInline |
					   LDSubfile::CacheInline |
					   LDSubfile::RendererInline);
			bool oldinvert = g_glInvert;

			if (ref->transform().determinant() < 0)
				g_glInvert = !g_glInvert;

			LDObject* prev = ref->prev();

			if (prev && prev->getType() == LDObject::BFC && static_cast<LDBFC*> (prev)->type == LDBFC::InvertNext)
				g_glInvert = !g_glInvert;

		for (LDObject * obj : objs)
			{	compileList (obj, list);
				delete obj;
			}

			g_glInvert = oldinvert;
		}
		break;

		default:
			break;
	}
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::compileVertex (const vertex& vrt)
{	glVertex3d (vrt[X], -vrt[Y], -vrt[Z]);
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::clampAngle (double& angle) const
{	while (angle < 0)
		angle += 360.0;

	while (angle > 360.0)
		angle -= 360.0;
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::addDrawnVertex (vertex pos)
{	// If we picked an already-existing vertex, stop drawing
for (vertex & vert : m_drawedVerts)
	{	if (vert == pos)
		{	endDraw (true);
			return;
		}
	}

	m_drawedVerts << pos;
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::mouseReleaseEvent (QMouseEvent* ev)
{	const bool wasLeft = (m_lastButtons & Qt::LeftButton) && ! (ev->buttons() & Qt::LeftButton),
				   wasRight = (m_lastButtons & Qt::RightButton) && ! (ev->buttons() & Qt::RightButton),
				   wasMid = (m_lastButtons & Qt::MidButton) && ! (ev->buttons() & Qt::MidButton);

	if (m_panning)
		m_panning = false;

	if (wasLeft)
	{	// Check if we selected a camera icon
		if (!m_rangepick)
		{	for (CameraIcon & info : m_cameraIcons)
			{	if (info.destRect.contains (ev->pos()))
				{	setCamera (info.cam);
					goto end;
				}
			}
		}

		switch (editMode())
		{
			case Draw:
			{	if (m_rectdraw)
				{	if (m_drawedVerts.size() == 2)
					{	endDraw (true);
						return;
					}
				}
				else
				{	// If we have 4 verts, stop drawing.
					if (m_drawedVerts.size() >= 4)
					{	endDraw (true);
						return;
					}

					if (m_drawedVerts.size() == 0 && ev->modifiers() & Qt::ShiftModifier)
					{	m_rectdraw = true;
						updateRectVerts();
					}
				}

				addDrawnVertex (m_hoverpos);
			} break;

			case CircleMode:
			{	if (m_drawedVerts.size() == 3)
				{	endDraw (true);
					return;
				}

				addDrawnVertex (m_hoverpos);
			} break;

			case Select:
			{	if (!drawOnly())
				{	if (m_totalmove < 10)
						m_rangepick = false;

					if (!m_rangepick)
						m_addpick = (m_keymods & Qt::ControlModifier);

					if (m_totalmove < 10 || m_rangepick)
						pick (ev->x(), ev->y());
				}
			} break;
		}

		m_rangepick = false;
	}

	if (wasMid && editMode() != Select && m_drawedVerts.size() < 4 && m_totalmove < 10)
	{	// Find the closest vertex to our cursor
		double mindist = 1024.0f;
		vertex closest;
		bool valid = false;

		QPoint curspos = coordconv3_2 (m_hoverpos);

		for (const vertex& pos3d: m_knownVerts)
		{	QPoint pos2d = coordconv3_2 (pos3d);

			// Measure squared distance
			const double dx = abs (pos2d.x() - curspos.x()),
						 dy = abs (pos2d.y() - curspos.y()),
						 distsq = (dx * dx) + (dy * dy);

			if (distsq >= 1024.0f) // 32.0f ** 2
				continue; // too far away

			if (distsq < mindist)
			{	mindist = distsq;
				closest = pos3d;
				valid = true;

				// If it's only 4 pixels away, I think we found our vertex now.
				if (distsq <= 16.0f) // 4.0f ** 2
					break;
			}
		}

		if (valid)
			addDrawnVertex (closest);
	}

	if (wasRight && m_drawedVerts.size() > 0)
	{	// Remove the last vertex
		m_drawedVerts.erase (m_drawedVerts.size() - 1);

		if (m_drawedVerts.size() == 0)
			m_rectdraw = false;
	}

end:
	update();
	m_totalmove = 0;
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::mousePressEvent (QMouseEvent* ev)
{	m_totalmove = 0;

	if (ev->modifiers() & Qt::ControlModifier)
	{	m_rangepick = true;
		m_rangeStart.setX (ev->x());
		m_rangeStart.setY (ev->y());
		m_addpick = (m_keymods & Qt::AltModifier);
		ev->accept();
	}

	m_lastButtons = ev->buttons();
}

// =============================================================================
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
// =============================================================================
void GLRenderer::mouseMoveEvent (QMouseEvent* ev)
{	int dx = ev->x() - m_pos.x();
	int dy = ev->y() - m_pos.y();
	m_totalmove += abs (dx) + abs (dy);

	const bool left = ev->buttons() & Qt::LeftButton,
			   mid = ev->buttons() & Qt::MidButton,
			   shift = ev->modifiers() & Qt::ShiftModifier;

	if (mid || (left && shift))
	{	m_panX += 0.03f * dx * (zoom() / 7.5f);
		m_panY -= 0.03f * dy * (zoom() / 7.5f);
		m_panning = true;
	} elif (left && !m_rangepick && camera() == Free)

	{	m_rotX = m_rotX + (dy);
		m_rotY = m_rotY + (dx);

		clampAngle (m_rotX);
		clampAngle (m_rotY);
	}

	// Start the tool tip timer
	if (!m_drawToolTip)
		m_toolTipTimer->start (500);

	// Update 2d position
	m_pos = ev->pos();
	m_globalpos = ev->globalPos();

	// Calculate 3d position of the cursor
	m_hoverpos = (camera() != Free) ? coordconv2_3 (m_pos, true) : g_origin;

	// Update rect vertices since m_hoverpos may have changed
	updateRectVerts();

	update();
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::keyPressEvent (QKeyEvent* ev)
{	m_keymods = ev->modifiers();
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::keyReleaseEvent (QKeyEvent* ev)
{	m_keymods = ev->modifiers();
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::wheelEvent (QWheelEvent* ev)
{	makeCurrent();

	zoomNotch (ev->delta() > 0);
	setZoom (clamp<double> (zoom(), 0.01f, 10000.0f));

	update();
	ev->accept();
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::leaveEvent (QEvent* ev)
{	(void) ev;
	m_drawToolTip = false;
	m_toolTipTimer->stop();
	update();
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::contextMenuEvent (QContextMenuEvent* ev)
{	g_win->spawnContextMenu (ev->globalPos());
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::setCamera (const GL::Camera cam)
{	m_camera = cam;
	gl_camera = (int) cam;
	g_win->updateEditModeActions();
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::pick (int mouseX, int mouseY)
{	GLint viewport[4];
	makeCurrent();

	// Use particularly thick lines while picking ease up selecting lines.
	glLineWidth (max<double> (gl_linethickness, 6.5f));

	// Clear the selection if we do not wish to add to it.
	if (!m_addpick)
	{	List<LDObject*> oldsel = g_win->sel();
		g_win->sel().clear();

	for (LDObject * obj : oldsel)
		{	obj->setSelected (false);
			compileObject (obj);
		}
	}

	m_picking = true;

	// Paint the picking scene
	glDisable (GL_DITHER);
	glClearColor (1.0f, 1.0f, 1.0f, 1.0f);

	drawGLScene();

	glGetIntegerv (GL_VIEWPORT, viewport);

	short x0 = mouseX,
		  y0 = mouseY;
	short x1, y1;

	// Determine how big an area to read - with range picking, we pick by
	// the area given, with single pixel picking, we use an 1 x 1 area.
	if (m_rangepick)
	{	x1 = m_rangeStart.x();
		y1 = m_rangeStart.y();
	}
	else
	{	x1 = x0 + 1;
		y1 = y0 + 1;
	}

	// x0 and y0 must be less than x1 and y1, respectively.
	if (x0 > x1)
		dataswap (x0, x1);

	if (y0 > y1)
		dataswap (y0, y1);

	// Clamp the values to ensure they're within bounds
	x0 = max<short> (0, x0);
	y0 = max<short> (0, y0);
	x1 = min<short> (x1, m_width);
	y1 = min<short> (y1, m_height);

	const short areawidth = (x1 - x0);
	const short areaheight = (y1 - y0);
	const long numpixels = areawidth * areaheight;

	// Allocate space for the pixel data.
	uchar* const pixeldata = new uchar[4 * numpixels];
	uchar* pixelptr = &pixeldata[0];

	assert (viewport[3] == m_height);

	// Read pixels from the color buffer.
	glReadPixels (x0, viewport[3] - y1, areawidth, areaheight, GL_RGBA, GL_UNSIGNED_BYTE, pixeldata);

	LDObject* removedObj = null;

	// Go through each pixel read and add them to the selection.
	for (long i = 0; i < numpixels; ++i)
	{	long idx =
			(* (pixelptr + 0) * 0x10000) +
			(* (pixelptr + 1) * 0x00100) +
			(* (pixelptr + 2) * 0x00001);
		pixelptr += 4;

		if (idx == 0xFFFFFF)
			continue; // White is background; skip

		LDObject* obj = LDObject::fromID (idx);

		// If this is an additive single pick and the object is currently selected,
		// we remove it from selection instead.
		if (!m_rangepick && m_addpick)
		{	bool removed = false;

			for (int i = 0; i < g_win->sel().size(); ++i)
			{	if (g_win->sel() [i] == obj)
				{	g_win->sel().erase (i);
					obj->setSelected (false);
					removed = true;
					removedObj = obj;
				}
			}

			if (removed)
				break;
		}

		g_win->sel() << obj;
	}

	delete[] pixeldata;

	// Remove duplicated entries
	g_win->sel().makeUnique();

	// Update everything now.
	g_win->updateSelection();

	// Recompile the objects now to update their color
for (LDObject * obj : g_win->sel())
		compileObject (obj);

	if (removedObj)
		compileObject (removedObj);

	// Restore line thickness
	glLineWidth (gl_linethickness);

	m_picking = false;
	m_rangepick = false;
	glEnable (GL_DITHER);

	setBackground();
	repaint();
}

// =============================================================================
// -----------------------------------------------------------------------------
READ_ACCESSOR (EditMode, GLRenderer::editMode)
{	return m_editMode;
}

// =============================================================================
// -----------------------------------------------------------------------------
SET_ACCESSOR (EditMode, GLRenderer::setEditMode)
{	m_editMode = val;

	switch (editMode())
	{	case Select:
		{	unsetCursor();
			setContextMenuPolicy (Qt::DefaultContextMenu);
		} break;

		case Draw:
		case CircleMode:
		{	// Cannot draw into the free camera - use top instead.
			if (m_camera == Free)
				setCamera (Top);

			// Disable the context menu - we need the right mouse button
			// for removing vertices.
			setContextMenuPolicy (Qt::NoContextMenu);

			// Use the crosshair cursor when drawing.
			setCursor (Qt::CrossCursor);

			// Clear the selection when beginning to draw.
			// FIXME: make the selection clearing stuff in ::pick a method and use it
			// here! This code doesn't update the GL lists.
			g_win->sel().clear();
			g_win->updateSelection();
			m_drawedVerts.clear();
		} break;
	}

	g_win->updateEditModeActions();
	update();
}

// =============================================================================
// -----------------------------------------------------------------------------
READ_ACCESSOR (LDFile*, GLRenderer::file)
{	return m_file;
}

// =============================================================================
// -----------------------------------------------------------------------------
SET_ACCESSOR (LDFile*, GLRenderer::setFile)
{	m_file = val;

	if (val != null)
		overlaysFromObjects();
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::endDraw (bool accept)
{	(void) accept;

	// Clean the selection and create the object
	List<vertex>& verts = m_drawedVerts;
	LDObject* obj = null;

	switch (editMode())
	{	case Draw:

			if (m_rectdraw)
			{	LDQuad* quad = new LDQuad;

				// Copy the vertices from m_rectverts
				updateRectVerts();

				for (int i = 0; i < quad->vertices(); ++i)
					quad->setVertex (i, m_rectverts[i]);

				quad->setColor (maincolor);
				obj = quad;
			}
			else
			{	switch (verts.size())
				{	case 1:
						// 1 vertex - add a vertex object
						obj = new LDVertex;
						static_cast<LDVertex*> (obj)->pos = verts[0];
						obj->setColor (maincolor);
						break;

					case 2:
						// 2 verts - make a line
						obj = new LDLine (verts[0], verts[1]);
						obj->setColor (edgecolor);
						break;

					case 3:
					case 4:
						obj = (verts.size() == 3) ?
							  static_cast<LDObject*> (new LDTriangle) :
							  static_cast<LDObject*> (new LDQuad);

						obj->setColor (maincolor);

						for (int i = 0; i < obj->vertices(); ++i)
							obj->setVertex (i, verts[i]);

						break;
				}
			}

			break;

		case CircleMode:
		{	const double dist = circleDrawDist (0);

			matrix transform = g_circleDrawTransforms[camera() % 3];

			for (int i = 0; i < 9; ++i)
			{	if (transform[i] == 2)
					transform[i] = dist;
				elif (transform[i] == 1 && camera() >= 3)
					transform[i] = -1;
			}

			LDSubfile* ref = new LDSubfile;
			ref->setFileInfo (findLoadedFile ("4-4edge.dat"));
			ref->setTransform (transform);
			ref->setPosition (m_drawedVerts[0]);
			ref->setColor (maincolor);
			obj = ref;
		}
		break;

		case Select:
			assert (false);
			return;
	}

	if (obj)
	{	g_win->beginAction (null);
		file()->addObject (obj);
		compileObject (obj);
		g_win->fullRefresh();
		g_win->endAction();
	}

	m_drawedVerts.clear();
	m_rectdraw = false;
}

// =============================================================================
// -----------------------------------------------------------------------------
double GLRenderer::circleDrawDist (int pos) const
{	assert (m_drawedVerts.size() >= pos + 1);
	const vertex& v1 = (m_drawedVerts.size() >= pos + 2) ? m_drawedVerts[pos + 1] : m_hoverpos;
	Axis relX, relY;
	getRelativeAxes (relX, relY);

	const double dx = m_drawedVerts[0][relX] - v1[relX];
	const double dy = m_drawedVerts[0][relY] - v1[relY];
	return sqrt ((dx * dx) + (dy * dy));
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::getRelativeAxes (Axis& relX, Axis& relY) const
{	const LDFixedCameraInfo* cam = &g_FixedCameras[m_camera];
	relX = cam->axisX;
	relY = cam->axisY;
}

// =============================================================================
// -----------------------------------------------------------------------------
static List<vertex> getVertices (LDObject* obj)
{	List<vertex> verts;

	if (obj->vertices() >= 2)
	{	for (int i = 0; i < obj->vertices(); ++i)
			verts << obj->getVertex (i);
	} elif (obj->getType() == LDObject::Subfile)

	{	LDSubfile* ref = static_cast<LDSubfile*> (obj);
		List<LDObject*> objs = ref->inlineContents (LDSubfile::DeepCacheInline);

	for (LDObject * obj : objs)
		{	verts << getVertices (obj);
			delete obj;
		}
	}

	return verts;
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::compileObject (LDObject* obj)
{	deleteLists (obj);

for (const GL::ListType listType : g_glListTypes)
	{	if (drawOnly() && listType != GL::NormalList)
			continue;

		GLuint list = glGenLists (1);
		glNewList (list, GL_COMPILE);

		obj->glLists[listType] = list;
		compileList (obj, listType);

		glEndList();
	}

	// Mark in known vertices of this object
	List<vertex> verts = getVertices (obj);
	m_knownVerts << verts;
	m_knownVerts.makeUnique();

	obj->m_glinit = true;
}

// =============================================================================
// -----------------------------------------------------------------------------
uchar* GLRenderer::screencap (int& w, int& h)
{	w = m_width;
	h = m_height;
	uchar* cap = new uchar[4 * w * h];

	m_screencap = true;
	update();
	m_screencap = false;

	// Capture the pixels
	glReadPixels (0, 0, w, h, GL_RGBA, GL_UNSIGNED_BYTE, cap);

	return cap;
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::slot_toolTipTimer()
{	// We come here if the cursor has stayed in one place for longer than a
	// a second. Check if we're holding it over a camera icon - if so, draw
	// a tooltip.
for (CameraIcon & icon : m_cameraIcons)
	{	if (icon.destRect.contains (m_pos))
		{	m_toolTipCamera = icon.cam;
			m_drawToolTip = true;
			update();
			break;
		}
	}
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::deleteLists (LDObject* obj)
{	// Delete the lists but only if they have been initialized
	if (!obj->m_glinit)
		return;

for (const GL::ListType listType : g_glListTypes)
		glDeleteLists (obj->glLists[listType], 1);

	obj->m_glinit = false;
}

// =============================================================================
// -----------------------------------------------------------------------------
Axis GLRenderer::cameraAxis (bool y, GL::Camera camid)
{	if (camid == (GL::Camera) - 1)
		camid = m_camera;

	const LDFixedCameraInfo* cam = &g_FixedCameras[camid];
	return (y) ? cam->axisY : cam->axisX;
}

// =============================================================================
// -----------------------------------------------------------------------------
bool GLRenderer::setupOverlay (GL::Camera cam, str file, int x, int y, int w, int h)
{	QImage* img = new QImage (file);
	LDGLOverlay& info = getOverlay (cam);

	if (img->isNull())
	{	critical (tr ("Failed to load overlay image!"));
		delete img;
		return false;
	}

	delete info.img; // delete the old image

	info.fname = file;
	info.lw = w;
	info.lh = h;
	info.ox = x;
	info.oy = y;
	info.img = img;

	if (info.lw == 0)
		info.lw = (info.lh * img->width()) / img->height();

	elif (info.lh == 0)
	info.lh = (info.lw * img->height()) / img->width();

	const Axis x2d = cameraAxis (false, cam),
			   y2d = cameraAxis (true, cam);

	double negXFac = g_FixedCameras[cam].negX ? -1 : 1,
		   negYFac = g_FixedCameras[cam].negY ? -1 : 1;

	info.v0 = info.v1 = g_origin;
	info.v0[x2d] = - (info.ox * info.lw * negXFac) / img->width();
	info.v0[y2d] = (info.oy * info.lh * negYFac) / img->height();
	info.v1[x2d] = info.v0[x2d] + info.lw;
	info.v1[y2d] = info.v0[y2d] + info.lh;

	// Set alpha of all pixels to 0.5
	for (long i = 0; i < img->width(); ++i)
		for (long j = 0; j < img->height(); ++j)
		{	uint32 pixel = img->pixel (i, j);
			img->setPixel (i, j, 0x80000000 | (pixel & 0x00FFFFFF));
		}

	updateOverlayObjects();
	return true;
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::clearOverlay()
{	if (camera() == Free)
		return;

	LDGLOverlay& info = m_overlays[camera()];
	delete info.img;
	info.img = null;

	updateOverlayObjects();
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::setDepthValue (double depth)
{	assert (camera() < Free);
	m_depthValues[camera()] = depth;
}

// =============================================================================
// -----------------------------------------------------------------------------
double GLRenderer::depthValue() const
{	assert (camera() < Free);
	return m_depthValues[camera()];
}

// =============================================================================
// -----------------------------------------------------------------------------
const char* GLRenderer::cameraName() const
{	return g_CameraNames[camera()];
}

// =============================================================================
// -----------------------------------------------------------------------------
LDGLOverlay& GLRenderer::getOverlay (int newcam)
{	return m_overlays[newcam];
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::zoomNotch (bool inward)
{	if (zoom() > 15)
		setZoom (zoom() * (inward ? 0.833f : 1.2f));
	else
		setZoom (zoom() + (inward ? -1.2f : 1.2f));
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::zoomToFit()
{	if (file() == null)
	{	setZoom (30.0f);
		return;
	}

	bool lastfilled = false;
	bool firstrun = true;
	const uint32 white = 0xFFFFFFFF;
	bool inward = true;
	int run = 0;
	const int w = m_width, h = m_height;

	glClearColor (1.0, 1.0, 1.0, 1.0);
	glDisable (GL_DITHER);

	// Use the pick list while drawing the scene, this way we can tell whether borders
	// are background or not.
	m_picking = true;

	for (;;)
	{	if (zoom() > 10000.0f || zoom() < 0.0f)
		{	// Obviously, there's nothing to draw if we get here.
			// Default to 30.0f and break out.
			setZoom (30.0f);
			break;
		}

		zoomNotch (inward);

		uchar* cap = new uchar[4 * w * h];
		drawGLScene();
		glReadPixels (0, 0, w, h, GL_RGBA, GL_UNSIGNED_BYTE, cap);
		uint32* imgdata = reinterpret_cast<uint32*> (cap);
		bool filled = false;

		// Check the top and bottom rows
		for (int i = 0; i < w && !filled; ++i)
			if (imgdata[i] != white || imgdata[ ( (h - 1) * w) + i] != white)
				filled = true;

		// Left and right edges
		for (int i = 0; i < h && !filled; ++i)
			if (imgdata[i * w] != white || imgdata[ (i * w) + (w - 1)] != white)
				filled = true;

		if (firstrun)
		{	// If this is the first run, we don't know enough to determine
			// whether the zoom was to fit, so we mark in our knowledge so
			// far and start over.
			inward = !filled;
			firstrun = false;
		}
		else
		{	// If this run filled the screen and the last one did not, the
			// last run had ideal zoom - zoom a bit back and we should reach it.
			if (filled && !lastfilled)
			{	zoomNotch (false);
				break;
			}

			// If this run did not fill the screen and the last one did, we've
			// now reached ideal zoom so we're done here.
			if (!filled && lastfilled)
				break;

			inward = !filled;
		}

		delete[] cap;
		lastfilled = filled;
		++run;
	}

	setBackground();
	m_picking = false;
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::updateRectVerts()
{	if (!m_rectdraw)
		return;

	if (m_drawedVerts.size() == 0)
	{	for (int i = 0; i < 4; ++i)
			m_rectverts[i] = m_hoverpos;

		return;
	}

	vertex v0 = m_drawedVerts[0],
		   v1 = (m_drawedVerts.size() >= 2) ? m_drawedVerts[1] : m_hoverpos;

	const Axis ax = cameraAxis (false),
			   ay = cameraAxis (true),
			   az = (Axis) (3 - ax - ay);

	for (int i = 0; i < 4; ++i)
		m_rectverts[i][az] = depthValue();

	m_rectverts[0][ax] = v0[ax];
	m_rectverts[0][ay] = v0[ay];
	m_rectverts[1][ax] = v1[ax];
	m_rectverts[1][ay] = v0[ay];
	m_rectverts[2][ax] = v1[ax];
	m_rectverts[2][ay] = v1[ay];
	m_rectverts[3][ax] = v0[ax];
	m_rectverts[3][ay] = v1[ay];
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::mouseDoubleClickEvent (QMouseEvent* ev)
{	if (! (ev->buttons() & Qt::LeftButton) || editMode() != Select)
		return;

	pick (ev->x(), ev->y());

	if (g_win->sel().size() == 0)
		return;

	g_win->beginAction (null);
	LDObject* obj = g_win->sel() [0];
	AddObjectDialog::staticDialog (obj->getType(), obj);
	g_win->endAction();
	ev->accept();
}

// =============================================================================
// -----------------------------------------------------------------------------
LDOverlay* GLRenderer::findOverlayObject (GLRenderer::Camera cam)
{	LDOverlay* ovlobj = null;

for (LDObject * obj : file()->objects())
	{	if (obj->getType() == LDObject::Overlay && static_cast<LDOverlay*> (obj)->camera() == cam)
		{	ovlobj = static_cast<LDOverlay*> (obj);
			break;
		}
	}

	return ovlobj;
}

// =============================================================================
// -----------------------------------------------------------------------------
// Read in overlays from the current file and update overlay info accordingly.
// -----------------------------------------------------------------------------
void GLRenderer::overlaysFromObjects()
{	for (Camera cam : g_Cameras)
	{	if (cam == Free)
			continue;

		LDGLOverlay& meta = m_overlays[cam];
		LDOverlay* ovlobj = findOverlayObject (cam);

		if (!ovlobj && meta.img)
		{	delete meta.img;
			meta.img = null;
		} elif (ovlobj && (!meta.img || meta.fname != ovlobj->filename()))

		setupOverlay (cam, ovlobj->filename(), ovlobj->x(), ovlobj->y(), ovlobj->width(), ovlobj->height());
	}
}

// =============================================================================
// -----------------------------------------------------------------------------
void GLRenderer::updateOverlayObjects()
{	for (Camera cam : g_Cameras)
	{	if (cam == Free)
			continue;

		LDGLOverlay& meta = m_overlays[cam];
		LDOverlay* ovlobj = findOverlayObject (cam);

		if (!meta.img && ovlobj)
		{	// If this is the last overlay image, we need to remove the empty space after it as well.
			LDObject* nextobj = ovlobj->next();

			if (nextobj && nextobj->getType() == LDObject::Empty)
			{	m_file->forgetObject (nextobj);
				delete nextobj;
			}

			// If the overlay object was there and the overlay itself is
			// not, remove the object.
			m_file->forgetObject (ovlobj);
			delete ovlobj;
		} elif (meta.img && !ovlobj)

		{	// Inverse case: image is there but the overlay object is
			// not, thus create the object.
			ovlobj = new LDOverlay;

			// Find a suitable position to place this object. We want to place
			// this into the header, which is everything up to the first scemantic
			// object. If we find another overlay object, place this object after
			// the last one found. Otherwise, place it before the first schemantic
			// object and put an empty object after it (though don't do this if
			// there was no schemantic elements at all)
			int i, lastOverlay = -1;
			bool found = false;

			for (i = 0; i < file()->numObjs(); ++i)
			{	LDObject* obj = file()->obj (i);

				if (obj->isScemantic())
				{	found = true;
					break;
				}

				if (obj->getType() == LDObject::Overlay)
					lastOverlay = i;
			}

			if (lastOverlay != -1)
				file()->insertObj (lastOverlay + 1, ovlobj);
			else
			{	file()->insertObj (i, ovlobj);

				if (found)
					file()->insertObj (i + 1, new LDEmpty);
			}
		}

		if (meta.img && ovlobj)
		{	ovlobj->setCamera (cam);
			ovlobj->setFilename (meta.fname);
			ovlobj->setX (meta.ox);
			ovlobj->setY (meta.oy);
			ovlobj->setWidth (meta.lw);
			ovlobj->setHeight (meta.lh);
		}
	}

	if (g_win->R() == this)
		g_win->refresh();
}