Geografic-Information-System/gui/wxpython/vdigit/driver_draw.cpp

/**
   \file driver_draw.cpp
   
   \brief Experimental C++ wxWidgets display driver

   This driver is designed for wxPython GRASS GUI (digitization tool).
   Draw vector map layer to PseudoDC.

   (C) by the GRASS Development Team
   This program is free software under the GNU General Public
   License (>=v2). Read the file COPYING that comes with GRASS
   for details.

   \author Martin Landa <landa.martin gmail.com>

   \date 2007-2008 
*/

#include <cmath>

#include "driver.h"

/**
   \brief Draw content of the vector map to device
   
   \return number of lines which were drawn
   \return -1 on error
 */
int DisplayDriver::DrawMap(bool force)
{
    if (!mapInfo || !dc)
	return -1;

    int nlines;
    BOUND_BOX mapBox;
    struct ilist *listLines;

    // ids.clear();
    listLines = Vect_new_list();

    ResetTopology();

    /* nlines = Vect_get_num_lines(mapInfo); */

    Vect_get_map_box(mapInfo, &mapBox);

    // draw lines inside of current display region
    nlines = Vect_select_lines_by_box(mapInfo, &(region.box),
     				      GV_POINTS | GV_LINES, // fixme
				      listLines);

    G_debug(3, "wxDriver.DrawMap(): region: w=%f, e=%f, s=%f, n=%f",
	    region.box.W, region.box.E, region.box.S, region.box.N);

    dc->BeginDrawing();

    if (settings.area.enabled) {
	/* draw area fills first */
	int area, centroid, isle;
	int num_isles;
	bool draw;
	struct ilist *listAreas, *listCentroids;
	struct line_pnts *points, *ipoints, **isles;

	wxBrush *fillArea, *fillAreaSelected, *fillIsle;

	fillArea = new wxBrush(settings.area.color);
	fillAreaSelected = new wxBrush(settings.highlight);
	fillIsle = new wxBrush(*wxWHITE_BRUSH);
	
	listAreas = Vect_new_list();
	listCentroids = Vect_new_list();
	
	points = Vect_new_line_struct();
	ipoints = NULL;

	Vect_select_areas_by_box(mapInfo, &region.box,
				 listAreas);

	for (int i = 0; i < listAreas->n_values; i++) {
	    area = listAreas->value[i];
	    
	    if (!Vect_area_alive (mapInfo, area))
		return -1;

	    /* check for other centroids -- only area with one centroid is valid */
	    centroid = Vect_get_area_centroid(mapInfo, area);

	    if(centroid > 0) {
		/* check for isles */
		num_isles = Vect_get_area_num_isles(mapInfo, area); /* TODO */
		if (num_isles < 1)
		    isles = NULL;
		else
		    isles = (struct line_pnts **) G_malloc(num_isles * sizeof(struct line_pnts *));
		for (int j = 0; j < num_isles; j++) {
		    ipoints = Vect_new_line_struct();
		    isle = Vect_get_area_isle(mapInfo, area, j);

		    if (!Vect_isle_alive (mapInfo, isle))
			return -1;

		    Vect_get_isle_points(mapInfo, isle, ipoints);
		    isles[j] = ipoints;
		}

		Vect_get_area_points(mapInfo, area, points);

		/* avoid processing areas with large number of polygon points (ugly) */
		if (points->n_points < 5000) {
		    Vect_select_lines_by_polygon(mapInfo, points,
						 num_isles, isles, GV_CENTROID, listCentroids);
		}
		else {
		    Vect_reset_list(listCentroids);
		}

		draw = true;
		for (int c = 0; c < listCentroids->n_values; c++) {
		    if(Vect_get_centroid_area(mapInfo, listCentroids->value[c]) < 0) {
			draw = false;
			break;
		    }
		}
		
		if (draw) {
		    int cat;
		    cat = Vect_get_area_cat(mapInfo, area, 1); /* TODO: field */
		    if (cat > -1 && IsSelected(cat, true)) {
			dc->SetBrush(*fillAreaSelected);
		    }
		    else {
			dc->SetBrush(*fillArea);
		    }
		    dc->SetPen(*wxTRANSPARENT_PEN);
		    DrawArea(points);

		    for (int j = 0; j < num_isles; j++) {
			/* draw isles in white */
			dc->SetBrush(*fillIsle);
			dc->SetPen(*wxTRANSPARENT_PEN);
			DrawArea(isles[j]);
		    }
		}

		if(isles) {
		    for (int j = 0; j < num_isles; j++) {
			Vect_destroy_line_struct(isles[j]);
			isles[j] = NULL;
		    }
		    G_free((void *) isles);
		}
	    }
	}

	delete fillArea;
	delete fillIsle;

	Vect_destroy_line_struct(points);

	Vect_destroy_list(listAreas);
	Vect_destroy_list(listCentroids);
    }

    for (int i = 0; i < listLines->n_values; i++) {
	DrawLine(listLines->value[i]);
    }
    dc->EndDrawing();

    // PrintIds();
    
    Vect_destroy_list(listLines);

    return listLines->n_values;
}	

/**
   \brief Draw area fill

   \param area boundary points

   \return 1 on success
   \return -1 on failure (vector object is dead, etc.)
*/
int DisplayDriver::DrawArea(const line_pnts* points)
{
    double x, y, z;

    // convert EN -> xy
    wxPoint wxPoints[points->n_points];

    for (int i = 0; i < points->n_points; i++) {
	Cell2Pixel(points->x[i], points->y[i], points->z[i],
		   &x, &y, &z);
	wxPoints[i] = wxPoint((int) x, (int) y);
    }

    // draw polygon
    dc->DrawPolygon(points->n_points, wxPoints);

    return 1;
}

/**
   \brief Draw selected vector objects to the device
 
   \param[in] line id

   \return 1 on success
   \return -1 on failure (vector object is dead, etc.)
*/
int DisplayDriver::DrawLine(int line)
{
    int dcId;       // 0 | 1 | segment id
    int type;       // line type
    double x, y, z; // screen coordinates
    bool draw;      // draw object ?
    wxPen *pen;
    
    pen = NULL;
    draw = false;

    if (!dc || !Vect_line_alive (mapInfo, line))
	return -1;

    // read line
    type = Vect_read_line (mapInfo, points, cats, line);

    // add ids
    // -> node1, line1, vertex1, line2, ..., node2
    // struct lineDesc desc = {points->n_points, dcId};
    // ids[line] = desc;
    // update id for next line
    // dcId += points->n_points * 2 - 1;

    if (IsSelected(line)) { // line selected ?
	if (settings.highlightDupl.enabled && IsDuplicated(line)) {
	    pen = new wxPen(settings.highlightDupl.color, settings.lineWidth, wxSOLID);
	}
	else {
	    pen = new wxPen(settings.highlight, settings.lineWidth, wxSOLID);
	}
	if (drawSelected) {
	    draw = true;
	}
	else {
	    draw = false;
	}
	dcId = 1;
	topology.highlight++;
    }
    else {
	dcId = 0;
	if (type & GV_LINES) {
	    switch (type) {
	    case GV_LINE:
		pen = new wxPen(settings.line.color, settings.lineWidth, wxSOLID);
		topology.line++;
		draw = settings.line.enabled;
		break;
	    case GV_BOUNDARY:
		int left, right;
		Vect_get_line_areas(mapInfo, line,
				    &left, &right);
		if (left == 0 && right == 0) {
		    pen = new wxPen(settings.boundaryNo.color, settings.lineWidth, wxSOLID);
		    topology.boundaryNo++;
		    draw = settings.boundaryNo.enabled;
		}
		else if (left > 0 && right > 0) {
		    pen = new wxPen(settings.boundaryTwo.color, settings.lineWidth, wxSOLID);
		    topology.boundaryTwo++;
		    draw = settings.boundaryTwo.enabled;
		}
		else {
		    pen = new wxPen(settings.boundaryOne.color, settings.lineWidth, wxSOLID);
		    topology.boundaryOne++;
		    draw = settings.boundaryOne.enabled;
		}
		break;
	    default:
		draw = false;
		break;
	    }
	}
	else if (type & GV_POINTS) {
	    if (type == GV_POINT && settings.point.enabled) {
		pen = new wxPen(settings.point.color, settings.lineWidth, wxSOLID);
		topology.point++;
		draw = settings.point.enabled;
	    }
	    else if (type == GV_CENTROID) {
		int cret = Vect_get_centroid_area(mapInfo, line);
		if (cret > 0) { // -> area
		    draw = settings.centroidIn.enabled;
		    pen = new wxPen(settings.centroidIn.color, settings.lineWidth, wxSOLID);
		    topology.centroidIn++;
		}
		else if (cret == 0) {
		    draw = settings.centroidOut.enabled;
		    pen = new wxPen(settings.centroidOut.color, settings.lineWidth, wxSOLID);
		    topology.centroidOut++;
		}
		else {
		    draw = settings.centroidDup.enabled;
		    pen = new wxPen(settings.centroidDup.color, settings.lineWidth, wxSOLID);
		    topology.centroidDup++;
		}
	    }
	}
    }
    
    // clear screen points & convert EN -> xy
    pointsScreen->Clear();
    for (int i = 0; i < points->n_points; i++) {
	Cell2Pixel(points->x[i], points->y[i], points->z[i],
		   &x, &y, &z);
	pointsScreen->Append((wxObject*) new wxPoint((int) x, (int) y)); /* TODO: 3D */
    }
    
    dc->SetId(dcId); /* 0 | 1 (selected) */
   
    if (draw) {
	dc->SetPen(*pen);
	if (type & GV_POINTS) {
	    DrawCross(line, (const wxPoint *) pointsScreen->GetFirst()->GetData());
	}
	else {
	    // long int startId = ids[line].startId + 1;
	    if (dcId > 0 && drawSegments) {
		dcId = 2; // first segment
		for (size_t i = 0; i < pointsScreen->GetCount() - 1; dcId += 2) {
		    wxPoint *point_beg = (wxPoint *) pointsScreen->Item(i)->GetData();
		    wxPoint *point_end = (wxPoint *) pointsScreen->Item(++i)->GetData();
		    
		    // set bounds for line
		    // wxRect rect (*point_beg, *point_end);
		    // dc->SetIdBounds(startId, rect);
		    
		    dc->SetId(dcId); // set unique id & set bbox for each segment
		    dc->SetPen(*pen);
		    wxRect rect (*point_beg, *point_end);
		    dc->SetIdBounds(dcId, rect);
		    dc->DrawLine(point_beg->x, point_beg->y,
				 point_end->x, point_end->y);
		}
	    }
	    else {
		wxPoint wxPoints[pointsScreen->GetCount()];
		for (size_t i = 0; i < pointsScreen->GetCount(); i++) {
		    wxPoint *point_beg = (wxPoint *) pointsScreen->Item(i)->GetData();
		    wxPoints[i] = *point_beg;
		}
		
		dc->DrawLines(pointsScreen->GetCount(), wxPoints);

		if (!IsSelected(line) && settings.direction.enabled) {
		    DrawDirectionArrow();
		    // restore pen
		    dc->SetPen(*pen);
		}
	    }
	}
    }

    if (type & GV_LINES) {
	DrawLineVerteces(line); // draw vertices
	DrawLineNodes(line);    // draw nodes
    }

    delete pen;

    return 1;
}

/**
   \brief Draw line verteces to the device
 
   Except of first and last vertex, see DrawLineNodes().

   \param line id

   \return number of verteces which were drawn
   \return -1 if drawing vertices is disabled
*/
int DisplayDriver::DrawLineVerteces(int line)
{
    int dcId;
    wxPoint *point;
    wxPen *pen;

    if (!IsSelected(line) && !settings.vertex.enabled)
	return -1;

    // determine color
    if (!IsSelected(line)) {
	pen = new wxPen(settings.vertex.color, settings.lineWidth, wxSOLID);
	dcId = 0;
    }
    else {
	if (!drawSelected) {
	    return -1;
	}
	if (settings.highlightDupl.enabled && IsDuplicated(line)) {
	    pen = new wxPen(settings.highlightDupl.color, settings.lineWidth, wxSOLID);
	}
	else {
	    pen = new wxPen(settings.highlight, settings.lineWidth, wxSOLID);
	}
	if (drawSegments) {
	    dcId = 3; // first vertex
	}
	else {
	    dcId = 1;
	}
    }

    dc->SetId(dcId); /* 0 | 1 (selected) */
    dc->SetPen(*pen);

    for (size_t i = 1; i < pointsScreen->GetCount() - 1; i++, dcId += 2) {
	point = (wxPoint*) pointsScreen->Item(i)->GetData();

	if (IsSelected(line) && drawSegments) {
	    dc->SetId(dcId);
	    dc->SetPen(*pen);
	    wxRect rect (*point, *point);
	    dc->SetIdBounds(dcId, rect);
	}
	
	if (settings.vertex.enabled) {
	    DrawCross(line, (const wxPoint*) pointsScreen->Item(i)->GetData());
	    topology.vertex++;
	}
    }

    delete pen;

    return pointsScreen->GetCount() - 2;
}

/**
   \brief Draw line nodes to the device
 
   \param line id

   \return 1
   \return -1 if no nodes were drawn
*/
int DisplayDriver::DrawLineNodes(int line)
{
    int dcId;
    int node;
    double east, north, depth;
    double x, y, z;
    int nodes [2];
    bool draw;

    wxPen *pen;

    // draw nodes??
    if (!settings.nodeOne.enabled && !settings.nodeTwo.enabled)
	return -1;

    // get nodes
    Vect_get_line_nodes(mapInfo, line, &(nodes[0]), &(nodes[1]));
        
    for (size_t i = 0; i < sizeof(nodes) / sizeof(int); i++) {
	node = nodes[i];
	// get coordinates
	Vect_get_node_coor(mapInfo, node,
			   &east, &north, &depth);

	// convert EN->xy
	Cell2Pixel(east, north, depth,
		   &x, &y, &z);

	// determine color
	if (IsSelected(line)) {
	    if (!drawSelected) {
		return -1;
	    }
	    if (settings.highlightDupl.enabled && IsDuplicated(line)) {
		pen = new wxPen(settings.highlightDupl.color, settings.lineWidth, wxSOLID);
	    }
	    else {
		pen = new wxPen(settings.highlight, settings.lineWidth, wxSOLID);
	    }
	    draw = true;
	    if (!drawSegments) {
		dcId = 1;
	    }
	    else {
		// node1, line1, vertex1, line2, vertex2, ..., node2
		if (i == 0) // first node
		    dcId = 1; 
		else // last node
		    dcId = 2 * points->n_points - 1;
	    }
	}
	else {
	    dcId = 0;
	    if (Vect_get_node_n_lines(mapInfo, node) == 1) {
		pen = new wxPen(settings.nodeOne.color, settings.lineWidth, wxSOLID);
		topology.nodeOne++;
		draw = settings.nodeOne.enabled;
	    }
	    else {
		pen = new wxPen(settings.nodeTwo.color, settings.lineWidth, wxSOLID);
		topology.nodeTwo++;
		draw = settings.nodeTwo.enabled;
	    }
	}
	
	wxPoint point((int) x, (int) y);
	if (IsSelected(line) && drawSegments) {
	    wxRect rect (point, point);
	    dc->SetIdBounds(dcId, rect);
	}

	// draw node if needed
	if (draw) {
	    dc->SetId(dcId);
	    dc->SetPen(*pen);
	    DrawCross(line, &point);
	}
    }
    
    delete pen;

    return 1;
}
/**
   \brief Draw cross symbol of given size to device content
   
   Used for points, nodes, vertices

   \param[in] point coordinates of center
   \param[in] size size of the cross symbol
   
   \return 1 on success
   \return -1 on failure
*/
int DisplayDriver::DrawCross(int line, const wxPoint* point, int size)
{
    if (!dc || !point)
	return -1;

    dc->DrawLine(point->x - size, point->y, point->x + size, point->y);
    dc->DrawLine(point->x, point->y - size, point->x, point->y + size);
    return 1;
}

/**
   \brief Draw selected features

   \param draw if true draw selected features
*/
void DisplayDriver::DrawSelected(bool draw)
{
    drawSelected = draw;

    return;
}

/**
   \brief Draw line direction arrow

   \return number of drawn arrows
*/
int DisplayDriver::DrawDirectionArrow()
{
    int narrows;
    int size; // arrow length in pixels
    int limit; // segment length limit for drawing symbol (in pixels)
    double dist, angle, pos;
    double e, n, d, x0, y0, z0, x1, y1, z1;
    struct line_pnts *points_seg;
    wxPen *pen_arrow;
    
    narrows = 0;
    size = 5;
    limit = 5; // 5px for line segment

    points_seg = Vect_new_line_struct();
    pen_arrow = new wxPen(settings.direction.color, settings.lineWidth, wxSOLID);

    dc->SetPen(*pen_arrow);

    dist = Vect_line_length(points);
    
    if (DistanceInPixels(dist) >= limit) {
	while (1) {
	    pos = (narrows + 1) * 8 * limit * region.map_res;

	    if (Vect_point_on_line(points, pos,
				   &e, &n, &d, NULL, NULL) < 1) {
		break;
	    }
	    
	    Cell2Pixel(e, n, d, &x0, &y0, &z0);
	    
	    if (Vect_point_on_line(points, pos - 3 * size * region.map_res,
				   &e, &n, &d, &angle, NULL) < 1) {
		break;
	    }
	    
	    Cell2Pixel(e, n, d, &x1, &y1, &z1);
	    
	    DrawArrow(x0, y0, x1, y1, angle, size);

	    if(narrows > 1e2) // low resolution, break
		break;

	    narrows++;
	}

	// draw at least one arrow in the middle of line
	if (narrows < 1) {
	    dist /= 2.;
	    if (Vect_point_on_line(points, dist,
				   &e, &n, &d, NULL, NULL) > 0) {
	    
		Cell2Pixel(e, n, d, &x0, &y0, &z0);
		
		if (Vect_point_on_line(points, dist - 3 * size * region.map_res,
				       &e, &n, &d, &angle, NULL) > 0) {
		    
		    Cell2Pixel(e, n, d, &x1, &y1, &z1);
		    
		    DrawArrow(x0, y0, x1, y1, angle, size);
		}
	    }
	}
    }

    Vect_destroy_line_struct(points_seg);
    
    return narrows;
}

/**
   \brief Draw arrow symbol on line

   \param x0,y0 arrow origin
   \param x1,x1 arrow ending point (on line)
   \param angle point ending point angle
   \param size arrow size

   \return 1
*/
int DisplayDriver::DrawArrow(double x0, double y0,
			     double x1, double y1, double angle,
			     int size)
{
    double x, y;
    double angle_symb;

    angle_symb = angle - M_PI / 2.;
    x = x1 + size * std::cos(angle_symb);
    y = y1 - size * std::sin(angle_symb);
    dc->DrawLine((wxCoord) x, (wxCoord) y, (wxCoord) x0, (wxCoord) y0);
    
    angle_symb = M_PI / 2. + angle;
    x = x1 + size * std::cos(angle_symb);
    y = y1 - size * std::sin(angle_symb);
    dc->DrawLine((wxCoord) x0, (wxCoord) y0, (wxCoord) x, (wxCoord) y);

    return 1;
}