Exemplo n.º 1
0
///////////////////////////////////////////////////////////////////////////////
// Called when applying an area style on a feature geometry.  Area styles can
// can only be applied to polygon feature geometry types.
void SE_Renderer::ProcessArea(SE_ApplyContext* ctx, SE_RenderAreaStyle* style)
{
    // the feature geometry we're applying the style on...
    LineBuffer* featGeom = ctx->geometry;

    // can't apply an area style to point and linestring geometry types
    switch (featGeom->geom_type())
    {
        case GeometryType_Point:
        case GeometryType_MultiPoint:
        case GeometryType_LineString:
        case GeometryType_MultiLineString:
        case GeometryType_CurveString:
        case GeometryType_MultiCurveString:
            return;
    }

    SE_Matrix w2s;
    GetWorldToScreenTransform(w2s);

    //--------------------------------------------------------------
    // special code to handle simple solid fill styles
    //--------------------------------------------------------------

    if (style->solidFill)
    {
        // just draw it and bail out of the layout function
        SE_RenderPolygon* rp = (SE_RenderPolygon*)style->symbol[0];

        if (m_bSelectionMode)
            DrawScreenPolygon(featGeom, &w2s, m_selFillColor);
        else
            DrawScreenPolygon(featGeom, &w2s, rp->fill);
        return;
    }

    // transform the feature geometry to rendering space
    LineBuffer* xfgeom = LineBufferPool::NewLineBuffer(m_pPool, featGeom->point_count());
    std::auto_ptr<LineBuffer> spLB(xfgeom);
    *xfgeom = *featGeom;

    int size = featGeom->point_count();
    for (int i=0; i<size; ++i)
        w2s.transform(xfgeom->x_coord(i), xfgeom->y_coord(i));

    // recompute the bounds
    RS_Bounds& bounds = const_cast<RS_Bounds&>(xfgeom->bounds());
    bounds.minx = bounds.miny = bounds.minz = +DBL_MAX;
    bounds.maxx = bounds.maxy = bounds.maxz = -DBL_MAX;
    xfgeom->ComputeBounds(bounds);

    // account for any viewport rotation
    SE_AreaPositioning ap(xfgeom, style, GetWorldToScreenRotation());
    double baserot = ap.PatternRotation();

    SE_Matrix xform;
    SE_Matrix xformbase = *ctx->xform;
    xformbase.rotate(baserot);

    for (const Point2D* pos = ap.NextLocation(); pos != NULL; pos = ap.NextLocation())
    {
        xform = xformbase;
        xform.translate(pos->x, pos->y);
        DrawSymbol(style->symbol, xform, baserot, style->addToExclusionRegion);
    }

    LineBufferPool::FreeLineBuffer(m_pPool, spLB.release());
}
Exemplo n.º 2
0
///////////////////////////////////////////////////////////////////////////////
// Called when applying a point style on a feature geometry.  Point styles can
// be applied to all feature geometry types.
void SE_Renderer::ProcessPoint(SE_ApplyContext* ctx, SE_RenderPointStyle* style, RS_Bounds* bounds)
{
    // the feature geometry we're applying the style on...
    LineBuffer* featGeom = ctx->geometry;

    double angleRad = 0.0;
    if (style->angleControl == SE_AngleControl_FromGeometry)
    {
        switch (featGeom->geom_type())
        {
            case GeometryType_LineString:
            case GeometryType_MultiLineString:
            case GeometryType_Polygon:
            case GeometryType_MultiPolygon:
            {
                double x0, y0;
                featGeom->Centroid(LineBuffer::ctLine, &x0, &y0, &angleRad);
                break;
            }
        }
    }

    angleRad += style->angleRad;

    // also account for any viewport rotation
    angleRad += GetWorldToScreenRotation();

    SE_Matrix xform;
    bool yUp = YPointsUp();

    // see StylizationEngine::Stylize for a detailed explanation of these transforms
    SE_Matrix xformbase;
    xformbase.translate(style->offset[0], style->offset[1]);
    xformbase.rotate(yUp? angleRad : -angleRad);
    xformbase.premultiply(*ctx->xform);

    // render the points
    for (int i=0; i<featGeom->point_count(); ++i)
    {
        double x, y;
        featGeom->get_point(i, x, y);

        // transform to screen space - feature geometry is in [the original] mapping space
        WorldToScreenPoint(x, y, x, y);

        xform = xformbase;
        xform.translate(x, y);

        if (style->drawLast)
            AddLabel(featGeom, style, xform, angleRad);
        else
            DrawSymbol(style->symbol, xform, angleRad, style->addToExclusionRegion);
    }

    if (bounds)
    {
        // get the symbol bounds after applying the transforms
        bounds->minx = bounds->miny = +DBL_MAX;
        bounds->maxx = bounds->maxy = -DBL_MAX;
        for (int i=0; i<4; ++i)
        {
            RS_F_Point xfpt;
            xformbase.transform(style->bounds[i].x, style->bounds[i].y, xfpt.x, xfpt.y);
            bounds->add_point(xfpt);
        }
    }
}
void SE_PositioningAlgorithms::MultipleHighwaysShields(SE_ApplyContext*  applyCtx,
                                                       SE_RenderStyle*   rstyle,
                                                       double            mm2su,
                                                       RS_FeatureReader* featureReader,
                                                       SE_SymbolManager* symbolManager)
{
    if (featureReader == NULL)
        return;

    SE_Renderer* se_renderer = applyCtx->renderer;
    LineBuffer* geometry = applyCtx->geometry;

    // this placement algorithm only applies to line styles
    if (rstyle->type != SE_RenderStyle_Line)
        return;

    SE_RenderLineStyle* rlStyle = (SE_RenderLineStyle*)rstyle;

    // ... and the units control must be absolute
    if (rlStyle->unitsControl != SE_UnitsControl_Absolute)
        return;

    // highway info format:  countryCode|type1|num1|type2|num2|type3|num3|...
    // example:              US|2|101|3|1
    StringOfTokens highwayInfo(featureReader->GetString(L"Url"), L"|");

    int shieldCount = (highwayInfo.getTokenCount() - 1) / 2;
    if (shieldCount < 1)
        return;

    double startOffset = rlStyle->startOffset;
    double increment = rlStyle->repeat;

    // the endOffset is used in this context as the increment between multiple shields in one group
//  double incrementS = 10.0 * mm2su;
    double incrementS = rlStyle->endOffset;

    // calc the overall length of this geometry
    double totalLen = 0.0;
    for (int i=0; i<geometry->cntr_count(); ++i)
    {
        int pt = geometry->contour_start_point(i);
        int last = geometry->contour_end_point(i);
        while (pt < last)
        {
            // transform the point to screen space
            double  cx1, cy1, cx2, cy2;
            se_renderer->WorldToScreenPoint(geometry->x_coord(pt), geometry->y_coord(pt), cx1, cy1);
            pt++;
            se_renderer->WorldToScreenPoint(geometry->x_coord(pt), geometry->y_coord(pt), cx2, cy2);

            // calc length
            double dx = cx2 - cx1;
            double dy = cy2 - cy1;
            totalLen += sqrt(dx*dx + dy*dy);
        }
    }

    if (startOffset >= 0.0)
    {
        // calc optimal start offset (with rlStyle->startOffset taken as a minimum)
        // to co-locate shield groups placed on two-line highways where the two
        // parallel lines are processed from opposit ends.
        // this avoids a problem with perceived irregular placement when overposting
        // removes just some of the duplicate shields

        double shieldGroupLen = (shieldCount - 1) * incrementS;

        // length in excess of the required length to place one group with startOffset on each side
        double availLen = totalLen - (shieldGroupLen + 2.0 * startOffset);

        if (availLen < 0.0)
        {
            // there is no room to 'properly' place even one group, nothing to do but cry about it
            return;
        }

        int numAdditionalGroups = (int) (availLen / (shieldGroupLen + increment));

        double additionalOffset = (availLen - numAdditionalGroups * (shieldGroupLen + increment)) / 2;

        startOffset += additionalOffset;
    }
    else
    {
        // negative startOffset value disables the optimization
        // use absolute value as the offset
        startOffset = -startOffset;
    }

    SE_RenderPrimitiveList* symbolVectors = new SE_RenderPrimitiveList[shieldCount];

    std::wstring countryCode = highwayInfo.getFirstToken();

    int shieldIndex;
    for (shieldIndex=0; shieldIndex<shieldCount; ++shieldIndex)
    {
        std::wstring shieldType = highwayInfo.getNextToken();
        std::wstring highwayNum = highwayInfo.getNextToken();

        // first the shield graphic

        SE_RenderRaster* rr = new SE_RenderRaster();

        std::wstring imgName = HIGWAY_SHIELD_SYMBOLS_PREFIX + countryCode + L"_" + shieldType + L".png";

        symbolManager->GetImageData(HIGWAY_SHIELD_SYMBOLS_RESOURCE.c_str(), imgName.c_str(), rr->imageData);

        if (rr->imageData.size == 0)
        {
            // could not find the image or resource

            // we could fall back and try to pick up the image from a disk file like this:
            //  std::wstring imgPathName = HIGWAY_SHIELD_SYMBOLS_LOCATION + imgName;
            //  rr->pngPtr = symbolManager->GetImageData(L"", imgPathName.c_str(), rr->pngSize);
            // but let's not do that unless really necessary

            // cannot just leave this shield empty, that causes exceptions later, so bail out
            // TODO: find a better way to handle this condition
            return;
        }

        rr->position[0] = 0.0;
        rr->position[1] = 0.0;
        rr->extent[0] = 20.0;
        rr->extent[1] = 20.0;
        rr->angleRad = 0.0;

        if (highwayNum.length() == 1)
            rr->extent[0] = ((shieldType == L"3")? 25.0 : 20.0);
        else if (highwayNum.length() == 2)
            rr->extent[0] = 25.0;
        else
            rr->extent[0] = 30.0;

        double w = 0.5 * rr->extent[0];
        double h = 0.5 * rr->extent[1];

        rr->bounds[0].x = -w;
        rr->bounds[0].y = -h;
        rr->bounds[1].x =  w;
        rr->bounds[1].y = -h;
        rr->bounds[2].x =  w;
        rr->bounds[2].y =  h;
        rr->bounds[3].x = -w;
        rr->bounds[3].y =  h;

        // the shield graphic is ready
        symbolVectors[shieldIndex].push_back(rr);

        // now symbol for the highway number
        SE_RenderText* rt = new SE_RenderText();

        rt->content = highwayNum;
        rt->position[0] = 0.0;
        rt->position[1] = 0.0;
        rt->tdef.font().name() = L"Arial";
        rt->tdef.font().height() = 10.0*0.001 / mm2su; // convert mm to meters
        rt->tdef.rotation() = 0.0;

        rt->tdef.halign() = RS_HAlignment_Center;
        rt->tdef.valign() = RS_VAlignment_Half;

        if (shieldType == L"1")
        {
            rt->tdef.textcolor() = RS_Color(255, 255, 255, 255);
        }
        else
        {
            rt->tdef.textcolor() = RS_Color(0, 0, 0, 255);
        }

        rt->tdef.textbg() = RS_TextBackground_None;
        rt->tdef.font().style() = RS_FontStyle_Bold;

        // the number graphic is ready
        symbolVectors[shieldIndex].push_back(rt);
    }

    SE_Matrix symxf;
    shieldIndex = 0;

    // account for any viewport rotation
    double angleRad = se_renderer->GetWorldToScreenRotation();

    // init position along the whole geometry to the start offset
    double drawpos = startOffset;

    for (int j=0; j<geometry->cntr_count(); ++j)
    {
        // current polyline
        int pt = geometry->contour_start_point(j);
        int last = geometry->contour_end_point(j);

        while (pt < last)
        {
            symxf.setIdentity();
            symxf.rotate(angleRad);

            // current line segment

            // transform the point to screen space
            double  cx1, cy1, cx2, cy2;
            se_renderer->WorldToScreenPoint(geometry->x_coord(pt), geometry->y_coord(pt), cx1, cy1);
            pt++;
            se_renderer->WorldToScreenPoint(geometry->x_coord(pt), geometry->y_coord(pt), cx2, cy2);

            // calc length
            double dx = cx2 - cx1;
            double dy = cy2 - cy1;
            double len = sqrt(dx*dx + dy*dy);

            // check if completely skipping current segment since it is smaller than the increment
            if (drawpos < len)
            {
                double invlen = 1.0 / len;
                double dx_fact = dx * invlen;
                double dy_fact = dy * invlen;

                double tx = cx1 + dx_fact * drawpos;
                double ty = cy1 + dy_fact * drawpos;
                symxf.translate(tx, ty);

                double dx_incr = dx_fact * increment;      // x/y incr between groups of shields
                double dy_incr = dy_fact * increment;

                double dx_incS = dx_fact * incrementS;     // x/y incr between shields in a group
                double dy_incS = dy_fact * incrementS;

                // follow the segment and place the shield symbols alternated via shieldIndex
                while (drawpos < len)
                {
                    if (rlStyle->drawLast)
                    {
                        rlStyle->symbol = symbolVectors[shieldIndex];
                        memcpy(rlStyle->bounds, symbolVectors[shieldIndex].front()->bounds, sizeof(rlStyle->bounds));
                        SE_RenderStyle* clonedStyle = se_renderer->CloneRenderStyle(rlStyle);

                        SE_LabelInfo info(symxf.x2, symxf.y2, RS_Units_Device, angleRad, clonedStyle);
                        RS_OverpostType overpostType = rlStyle->checkExclusionRegion? RS_OverpostType_AllFit : RS_OverpostType_All;
                        se_renderer->ProcessSELabelGroup(&info, 1, overpostType, rlStyle->addToExclusionRegion, geometry);
                    }
                    else
                    {
                        se_renderer->DrawSymbol(symbolVectors[shieldIndex], symxf, angleRad);

                        // TODO: if this is ever needed ...
//                      if (rlStyle->addToExclusionRegion)
//                          se_renderer->AddExclusionRegion(style, symxf, 0.0);
                    }

                    // move on to the next shield, if beyond the last one go back to the first
                    shieldIndex++;
                    if (shieldIndex < shieldCount)
                    {
                        symxf.translate(dx_incS, dy_incS);
                        drawpos += incrementS;
                    }
                    else
                    {
                        // finished with one group
                        // go back to the first symbol and advance using the full increment

                        shieldIndex = 0;
                        symxf.translate(dx_incr, dy_incr);
                        drawpos += increment;
                    }
                }
            }

            drawpos -= len;
        }
    }

    // cleanup time

    // the rlStyle->symbol has been assigned various values from the 'symbolVectors',
    // 'un-assign' it, so that we can clean them up
    rlStyle->symbol.clear();

    for (shieldIndex=0; shieldIndex<shieldCount; ++shieldIndex)
    {
        for (SE_RenderPrimitiveList::iterator iter = symbolVectors[shieldIndex].begin();
             iter != symbolVectors[shieldIndex].end(); ++iter)
        {
            // necessary since destructor of SE_RenderPrimitive is not virtual
            switch ((*iter)->type)
            {
                case SE_RenderPrimitive_Polyline:
                    delete (SE_RenderPolyline*)(*iter);
                    break;

                case SE_RenderPrimitive_Polygon:
                    delete (SE_RenderPolygon*)(*iter);
                    break;

                case SE_RenderPrimitive_Raster:
                    delete (SE_RenderRaster*)(*iter);
                    break;

                case SE_RenderPrimitive_Text:
                    delete (SE_RenderText*)(*iter);
                    break;

                default:
                    throw; // means there is a bug
            }
        }
    }

    delete [] symbolVectors;
}
void SE_PositioningAlgorithms::Default(SE_ApplyContext* applyCtx,
                                       SE_RenderStyle*  rstyle)
{
    // the style needs to contain at least one primitive
    SE_RenderPrimitiveList& prims = rstyle->symbol;
    if (prims.size() == 0)
        return;

    SE_Renderer* se_renderer = applyCtx->renderer;
    LineBuffer* geometry = applyCtx->geometry;
    SE_Matrix& xform = *applyCtx->xform;

    double cx = 0.0;
    double cy = 0.0;
    double offsetX = 0.0;
    double offsetY = 0.0;
    double angleRad = 0.0;

    switch (rstyle->type)
    {
        case SE_RenderStyle_Point:
        {
            SE_RenderPointStyle* rpStyle = (SE_RenderPointStyle*)rstyle;

            // get the feature centroid (no angle for point centroids)
            geometry->Centroid(LineBuffer::ctPoint, &cx, &cy, NULL);

            // account for the point usage angle control and offset
            angleRad = rpStyle->angleRad;
            offsetX  = rpStyle->offset[0];
            offsetY  = rpStyle->offset[1];

            break;
        }

        case SE_RenderStyle_Line:
        {
            SE_RenderLineStyle* rlStyle = (SE_RenderLineStyle*)rstyle;

            // get the feature centroid and angle
            double fAngleRad;
            geometry->Centroid(LineBuffer::ctLine, &cx, &cy, &fAngleRad);

            // account for the angle control
            angleRad = rlStyle->angleRad;
            if (rlStyle->angleControl == SE_AngleControl_FromGeometry)
                angleRad += fAngleRad;

            break;
        }

        case SE_RenderStyle_Area:
        {
            SE_RenderAreaStyle* raStyle = (SE_RenderAreaStyle*)rstyle;

            // get the feature centroid (no angle for area centroids)
            geometry->Centroid(LineBuffer::ctArea, &cx, &cy, NULL);

            // account for the angle control
            angleRad = raStyle->angleRad;

            break;
        }
    }

    // don't add a label if we can't compute the centroid
    if (_isnan(cx) || _isnan(cy))
        return;

    // need to convert centroid to screen units
    se_renderer->WorldToScreenPoint(cx, cy, cx, cy);

    // also account for any viewport rotation
    angleRad += se_renderer->GetWorldToScreenRotation();

    // see StylizationEngine::Stylize for a detailed explanation of these transforms
    bool yUp = se_renderer->YPointsUp();
    SE_Matrix xformLabel;
    xformLabel.translate(offsetX, offsetY);
    xformLabel.rotate(yUp? angleRad : -angleRad);
    xformLabel.premultiply(xform);
    xformLabel.translate(cx, cy);

    se_renderer->AddLabel(geometry, rstyle, xformLabel, angleRad);
}
void SE_PositioningAlgorithms::EightSurrounding(SE_ApplyContext* applyCtx,
                                                SE_RenderStyle*  rstyle,
                                                double           mm2su)
{
    SE_Renderer* se_renderer = applyCtx->renderer;
    LineBuffer* geometry = applyCtx->geometry;

    // eight surrounding labeling only applies to point feature geometry
    switch (geometry->geom_type())
    {
        case GeometryType_Point:
        case GeometryType_MultiPoint:
            break;

        default:
            return;
    }

    // eight surrounding labeling only works with point styles
    if (rstyle->type != SE_RenderStyle_Point)
        return;

    // the style needs to contain at least one primitive
    SE_RenderPrimitiveList& prims = rstyle->symbol;
    if (prims.size() == 0)
        return;

    SE_RenderPointStyle* rpstyle = (SE_RenderPointStyle*)rstyle;

    // get actual feature point and transform to screen space
    // TODO: in the case of a multi-point feature we get the average of all the points;
    //       generating candidate labels around this point doesn't make a whole lot of
    //       sense
    double cx = 0.0;
    double cy = 0.0;
    geometry->Centroid(LineBuffer::ctPoint, &cx, &cy, NULL);

    // don't add a label if we can't compute the centroid
    if (_isnan(cx) || _isnan(cy))
        return;

    se_renderer->WorldToScreenPoint(cx, cy, cx, cy);

    // Get the extent of the last drawn point symbol so that we know how much to offset
    // the label.  This call assumes the symbol draws right before the label.
    // TODO: remove this assumption
    const RS_F_Point* cfpts = se_renderer->GetLastSymbolExtent();
    RS_F_Point fpts[4];
    if(cfpts[0].x == 0 && cfpts[0].y == 0 &&
        cfpts[1].x == 0 && cfpts[1].y == 0 &&
        cfpts[2].x == 0 && cfpts[2].y == 0 &&
        cfpts[3].x == 0 && cfpts[3].y == 0)
    {
        for (int i=0; i<4; ++i)
        {
            fpts[i].x = cx;
            fpts[i].y = cy;
        }
    }
    else
        memcpy(fpts, cfpts, 4*sizeof(RS_F_Point));

    double dx = fpts[1].x - fpts[0].x;
    double dy = fpts[1].y - fpts[0].y;
    double symbol_rot_rad = atan2(dy, dx);

    // factor out position and rotation
    SE_Matrix ixform;
    ixform.translate(-cx, -cy);     // factor out point position
    ixform.rotate(-symbol_rot_rad); // factor out rotation
    for (int i=0; i<4; ++i)
        ixform.transform(fpts[i].x, fpts[i].y);

    bool yUp = se_renderer->YPointsUp();
    if (!yUp)
        symbol_rot_rad = -symbol_rot_rad;

    // unrotated bounds
    RS_Bounds symbol_bounds(fpts[0].x, fpts[0].y, fpts[2].x, fpts[2].y);
    double symbol_width  = symbol_bounds.width();   // symbol width in screen units
    double symbol_height = symbol_bounds.height();  // symbol height in screen units

    // offset the label from the symbol's edge
    double offset = POINT_LABEL_OFFSET_MM * mm2su;  // offset in screen units

    // make sure we have at least one pixel's worth of offset
    double screenUnitsPerPixel = MILLIMETERS_PER_INCH * se_renderer->GetScreenUnitsPerMillimeterDevice() / se_renderer->GetDpi();
    if (offset < screenUnitsPerPixel)
        offset = screenUnitsPerPixel;

    // compute how far label needs to be offset from center point of symbol
    double w2 = 0.5 * symbol_width;
    double h2 = 0.5 * symbol_height;
    double ch = 0.0;    // vertical center point
    double cw = 0.0;    // horizontal center point

    w2 += offset;
    h2 += offset;

    bool useBounds = symbol_bounds.IsValid();
    if (useBounds)
    {
        symbol_bounds.maxx += offset;    symbol_bounds.maxy += offset;
        symbol_bounds.minx -= offset;    symbol_bounds.miny -= offset;
        ch = 0.5*(symbol_bounds.maxy + symbol_bounds.miny);
        cw = 0.5*(symbol_bounds.maxx + symbol_bounds.minx);
    }

    // get the viewport rotation
    double w2sAngleRad = se_renderer->GetWorldToScreenRotation();

    // take into account rotation of the symbol - find increased extents
    // of the symbol bounds due to the rotation
    double op_pts[16];
    if (symbol_rot_rad != 0.0)
    {
        double cs = cos(symbol_rot_rad);
        double sn = sin(symbol_rot_rad);

        // check to see if the bounds have been set
        double wcs, nwcs, wsn, nwsn, hsn, nhsn, hcs, nhcs, cwsn, cwcs, chsn, chcs;
        if (useBounds)
        {
            wcs = symbol_bounds.maxx * cs;   nwcs = symbol_bounds.minx * cs;
            wsn = symbol_bounds.maxx * sn;   nwsn = symbol_bounds.minx * sn;
            hsn = symbol_bounds.maxy * sn;   nhsn = symbol_bounds.miny * sn;
            hcs = symbol_bounds.maxy * cs;   nhcs = symbol_bounds.miny * cs;
        }
        else
        {
            wcs = w2 * cs;   nwcs = -wcs;
            wsn = w2 * sn;   nwsn = -wsn;
            hsn = h2 * sn;   nhsn = -hsn;
            hcs = h2 * cs;   nhcs = -hcs;
        }

        cwsn = cw * sn;     chsn = ch * sn;
        cwcs = cw * cs;     chcs = ch * cs;

        // Find the octant that the symbol is rotated into, and shift the points accordingly.
        // This way the overpost points are still within 22.5 degrees of an axis-aligned box
        // (position 0 will always be the closest to Center-Right).
        // NOTE: The symbol rotation includes the viewport rotation.  We want to use the
        //       relative angle between these to compute the quadrant (it's the angle of
        //       the symbol relative to the viewport which matters).
        double relativeAngle = symbol_rot_rad - w2sAngleRad;
        double nangle = fmod(relativeAngle * M_180PI, 360.0);
        if (nangle < 0.0)
            nangle += 360.0;
        int i = (((int)((nangle/45.0) + 0.5)) << 1) & 0x0000000f; // i is 2 * the octant
        op_pts[i++] =  wcs - chsn;  op_pts[i++] =  wsn + chcs;  i &= 0x0000000f; // & 15 does (mod 16)
        op_pts[i++] =  wcs -  hsn;  op_pts[i++] =  wsn +  hcs;  i &= 0x0000000f;
        op_pts[i++] = cwcs -  hsn;  op_pts[i++] = cwsn +  hcs;  i &= 0x0000000f;
        op_pts[i++] = nwcs -  hsn;  op_pts[i++] = nwsn +  hcs;  i &= 0x0000000f;
        op_pts[i++] = nwcs - chsn;  op_pts[i++] = nwsn + chcs;  i &= 0x0000000f;
        op_pts[i++] = nwcs - nhsn;  op_pts[i++] = nwsn + nhcs;  i &= 0x0000000f;
        op_pts[i++] = cwcs - nhsn;  op_pts[i++] = cwsn + nhcs;  i &= 0x0000000f;
        op_pts[i++] =  wcs - nhsn;  op_pts[i  ] =  wsn + nhcs;
    }
    else
    {
        if (!useBounds)
        {
            symbol_bounds.maxx = w2; symbol_bounds.minx = -w2;
            symbol_bounds.maxy = h2; symbol_bounds.miny = -h2;
        }
        op_pts[0 ] = symbol_bounds.maxx; op_pts[1 ] = ch;
        op_pts[2 ] = symbol_bounds.maxx; op_pts[3 ] = symbol_bounds.maxy;
        op_pts[4 ] = cw;                 op_pts[5 ] = symbol_bounds.maxy;
        op_pts[6 ] = symbol_bounds.minx; op_pts[7 ] = symbol_bounds.maxy;
        op_pts[8 ] = symbol_bounds.minx; op_pts[9 ] = ch;
        op_pts[10] = symbol_bounds.minx; op_pts[11] = symbol_bounds.miny;
        op_pts[12] = cw;                 op_pts[13] = symbol_bounds.miny;
        op_pts[14] = symbol_bounds.maxx; op_pts[15] = symbol_bounds.miny;
    }

    // check if the incoming point style contains just a single text element
    bool foundSingleText = false;
    if (prims.size() == 1)
    {
        if (prims[0]->type == SE_RenderPrimitive_Text)
            foundSingleText = true;
    }

    // OK, who says I can't write bad code? Behold:
    SE_LabelInfo candidates[8];
    double yScale = yUp? 1.0 : -1.0; // which way does y go in the renderer?

    double angleRad = rpstyle->angleRad;

    // also account for the viewport rotation
    angleRad += w2sAngleRad;

    if (foundSingleText)
    {
        // In this case we set the appropriate alignments for the single text element
        // in each candidate label.  This allows us to draw the symbol directly at the
        // candidate points surrounding the feature point.

        SE_RenderStyle* st0 = se_renderer->CloneRenderStyle(rpstyle);
        ((SE_RenderText*)st0->symbol[0])->tdef.halign() = RS_HAlignment_Left;
        ((SE_RenderText*)st0->symbol[0])->tdef.valign() = RS_VAlignment_Half;
        UpdateStyleBounds(st0, se_renderer);
        candidates[0].Set(cx + op_pts[ 0], cy + op_pts[ 1]*yScale, RS_Units_Device, angleRad, st0);

        SE_RenderStyle* st1 = se_renderer->CloneRenderStyle(st0);
        ((SE_RenderText*)st1->symbol[0])->tdef.valign() = RS_VAlignment_Descent;
        UpdateStyleBounds(st1, se_renderer);
        candidates[1].Set(cx + op_pts[ 2], cy + op_pts[ 3]*yScale, RS_Units_Device, angleRad, st1);

        SE_RenderStyle* st2 = se_renderer->CloneRenderStyle(st1);
        ((SE_RenderText*)st2->symbol[0])->tdef.halign() = RS_HAlignment_Center;
        UpdateStyleBounds(st2, se_renderer);
        candidates[2].Set(cx + op_pts[ 4], cy + op_pts[ 5]*yScale, RS_Units_Device, angleRad, st2);

        SE_RenderStyle* st3 = se_renderer->CloneRenderStyle(st2);
        ((SE_RenderText*)st3->symbol[0])->tdef.halign() = RS_HAlignment_Right;
        UpdateStyleBounds(st3, se_renderer);
        candidates[3].Set(cx + op_pts[ 6], cy + op_pts[ 7]*yScale, RS_Units_Device, angleRad, st3);

        SE_RenderStyle* st4 = se_renderer->CloneRenderStyle(st3);
        ((SE_RenderText*)st4->symbol[0])->tdef.valign() = RS_VAlignment_Half;
        UpdateStyleBounds(st4, se_renderer);
        candidates[4].Set(cx + op_pts[ 8], cy + op_pts[ 9]*yScale, RS_Units_Device, angleRad, st4);

        SE_RenderStyle* st5 = se_renderer->CloneRenderStyle(st4);
        ((SE_RenderText*)st5->symbol[0])->tdef.valign() = RS_VAlignment_Ascent;
        UpdateStyleBounds(st5, se_renderer);
        candidates[5].Set(cx + op_pts[10], cy + op_pts[11]*yScale, RS_Units_Device, angleRad, st5);

        SE_RenderStyle* st6 = se_renderer->CloneRenderStyle(st5);
        ((SE_RenderText*)st6->symbol[0])->tdef.halign() = RS_HAlignment_Center;
        UpdateStyleBounds(st6, se_renderer);
        candidates[6].Set(cx + op_pts[12], cy + op_pts[13]*yScale, RS_Units_Device, angleRad, st6);

        SE_RenderStyle* st7 = se_renderer->CloneRenderStyle(st6);
        ((SE_RenderText*)st7->symbol[0])->tdef.halign() = RS_HAlignment_Left;
        UpdateStyleBounds(st7, se_renderer);
        candidates[7].Set(cx + op_pts[14], cy + op_pts[15]*yScale, RS_Units_Device, angleRad, st7);
    }
    else
    {
        // In the general case we have to account for the label symbol's extents when we
        // position each candidate.  For example, for candidate 1 (top right) we adjust the
        // position so that the bottom left corner of the label symbol's extent ends up at
        // the top right candidate point.

        double labelMinX = rpstyle->bounds[0].x;
        double labelMinY = rpstyle->bounds[0].y;
        double labelMaxX = rpstyle->bounds[2].x;
        double labelMaxY = rpstyle->bounds[2].y;
        double labelCtrX = 0.5*(labelMinX + labelMaxX);
        double labelCtrY = 0.5*(labelMinY + labelMaxY);

        SE_RenderStyle* st0 = se_renderer->CloneRenderStyle(rpstyle);
        candidates[0].Set(cx + op_pts[ 0] - labelMinX, cy + (op_pts[ 1] - labelCtrY)*yScale, RS_Units_Device, angleRad, st0);

        SE_RenderStyle* st1 = se_renderer->CloneRenderStyle(st0);
        candidates[1].Set(cx + op_pts[ 2] - labelMinX, cy + (op_pts[ 3] - labelMinY)*yScale, RS_Units_Device, angleRad, st1);

        SE_RenderStyle* st2 = se_renderer->CloneRenderStyle(st1);
        candidates[2].Set(cx + op_pts[ 4] - labelCtrX, cy + (op_pts[ 5] - labelMinY)*yScale, RS_Units_Device, angleRad, st2);

        SE_RenderStyle* st3 = se_renderer->CloneRenderStyle(st2);
        candidates[3].Set(cx + op_pts[ 6] - labelMaxX, cy + (op_pts[ 7] - labelMinY)*yScale, RS_Units_Device, angleRad, st3);

        SE_RenderStyle* st4 = se_renderer->CloneRenderStyle(st3);
        candidates[4].Set(cx + op_pts[ 8] - labelMaxX, cy + (op_pts[ 9] - labelCtrY)*yScale, RS_Units_Device, angleRad, st4);

        SE_RenderStyle* st5 = se_renderer->CloneRenderStyle(st4);
        candidates[5].Set(cx + op_pts[10] - labelMaxX, cy + (op_pts[11] - labelMaxY)*yScale, RS_Units_Device, angleRad, st5);

        SE_RenderStyle* st6 = se_renderer->CloneRenderStyle(st5);
        candidates[6].Set(cx + op_pts[12] - labelCtrX, cy + (op_pts[13] - labelMaxY)*yScale, RS_Units_Device, angleRad, st6);

        SE_RenderStyle* st7 = se_renderer->CloneRenderStyle(st6);
        candidates[7].Set(cx + op_pts[14] - labelMinX, cy + (op_pts[15] - labelMaxY)*yScale, RS_Units_Device, angleRad, st7);
    }

    se_renderer->ProcessSELabelGroup(candidates, 8, RS_OverpostType_FirstFit, true, NULL);
}