C++ FloatPoint类代码示例

void Path::moveTo(const FloatPoint& point)
{
    CGPathMoveToPoint(m_path, 0, point.x(), point.y());
}

void Path::addQuadCurveTo(const FloatPoint& cp, const FloatPoint& p)
{
    CGPathAddQuadCurveToPoint(m_path, 0, cp.x(), cp.y(), p.x(), p.y());
}

void SVGDocument::startPan(const FloatPoint& start)
{
    if (rootElement())
        m_translate = FloatPoint(start.x() - rootElement()->currentTranslate().x(), rootElement()->currentTranslate().y() + start.y());
}

static PassOwnPtr<Shape> createEllipseShape(const FloatPoint& center, const FloatSize& radii)
{
    ASSERT(radii.width() >= 0 && radii.height() >= 0);
    return adoptPtr(new RectangleShape(FloatRect(center.x() - radii.width(), center.y() - radii.height(), radii.width()*2, radii.height()*2), radii));
}

void Path::addArc(const FloatPoint& p, float r, float sa, float ea, bool clockwise)
{
    // Workaround for <rdar://problem/5189233> CGPathAddArc hangs or crashes when passed inf as start or end angle
    if (isfinite(sa) && isfinite(ea))
        CGPathAddArc(m_path, 0, p.x(), p.y(), r, sa, ea, clockwise);
}

void Path::addLineTo(const FloatPoint& p)
{
    m_path->lineTo(SkFloatToScalar(p.x()), SkFloatToScalar(p.y()));
}

void Path::addQuadCurveTo(const FloatPoint& cp, const FloatPoint& ep)
{
    m_path->quadTo( SkFloatToScalar(cp.x()), SkFloatToScalar(cp.y()),
                    SkFloatToScalar(ep.x()), SkFloatToScalar(ep.y()));
}

void Path::moveTo(const FloatPoint& point)
{
    m_path->moveTo(SkFloatToScalar(point.x()), SkFloatToScalar(point.y()));
}

void drawTextWithSpacing(GraphicsContext* graphicsContext, const SimpleFontData* font, const wxColour& color, const GlyphBuffer& glyphBuffer, int from, int numGlyphs, const FloatPoint& point)
{
    graphicsContext->save();
    
    wxGCDC* dc = static_cast<wxGCDC*>(graphicsContext->platformContext());

    wxFont* wxfont = font->getWxFont();
    graphicsContext->setFillColor(graphicsContext->fillColor());

    CGContextRef cgContext = static_cast<CGContextRef>(dc->GetGraphicsContext()->GetNativeContext());

    CGFontRef cgFont;

#ifdef wxOSX_USE_CORE_TEXT && wxOSX_USE_CORE_TEXT
    cgFont = CTFontCopyGraphicsFont((CTFontRef)font->OSXGetCTFont(), NULL);
#else
    ATSFontRef fontRef;
    
    fontRef = FMGetATSFontRefFromFont(wxfont->MacGetATSUFontID());
    
    if (fontRef)
        cgFont = CGFontCreateWithPlatformFont((void*)&fontRef);
#endif
    
    CGContextSetFont(cgContext, cgFont);

    CGContextSetFontSize(cgContext, wxfont->GetPointSize());

    CGFloat red, green, blue, alpha;
    graphicsContext->fillColor().getRGBA(red, green, blue, alpha);
    CGContextSetRGBFillColor(cgContext, red, green, blue, alpha);

    CGAffineTransform matrix = CGAffineTransformIdentity;
    matrix.b = -matrix.b;
    matrix.d = -matrix.d;
    
    CGContextSetTextMatrix(cgContext, matrix);

    CGContextSetTextPosition(cgContext, point.x(), point.y());
    
    const FloatSize* advanceSizes = static_cast<const FloatSize*>(glyphBuffer.advances(from));
    int size = glyphBuffer.size() - from;
    CGSize sizes[size];
    CGGlyph glyphs[numGlyphs];
    
    // if the function doesn't exist, we're probably on tiger and need to grab the
    // function under its old name, CGFontGetGlyphsForUnicodes
    if (!CGFontGetGlyphsForUnichars)
        CGFontGetGlyphsForUnichars = (CGFontGetGlyphsForUnicharsPtr)dlsym(RTLD_DEFAULT, "CGFontGetGlyphsForUnicodes");
    
    // Let's make sure we got the function under one name or another!
    ASSERT(CGFontGetGlyphsForUnichars);
    CGFontGetGlyphsForUnichars(cgFont, glyphBuffer.glyphs(from), glyphs, numGlyphs);
    
    for (int i = 0; i < size; i++) {
        FloatSize fsize = advanceSizes[i];
        sizes[i] = CGSizeMake(fsize.width(), fsize.height());
    }
    
    CGContextShowGlyphsWithAdvances(cgContext, glyphs, sizes, numGlyphs);
    
    if (cgFont)
        CGFontRelease(cgFont);
    graphicsContext->restore();
}

void Path::addArcTo(const FloatPoint& p1, const FloatPoint& p2, float radius)
{
    if (isEmpty())
        return;

    cairo_t* cr = platformPath()->context();

    double x0, y0;
    cairo_get_current_point(cr, &x0, &y0);
    FloatPoint p0(x0, y0);

    // Draw only a straight line to p1 if any of the points are equal or the radius is zero
    // or the points are collinear (triangle that the points form has area of zero value).
    if ((p1.x() == p0.x() && p1.y() == p0.y()) || (p1.x() == p2.x() && p1.y() == p2.y()) || !radius
        || !areaOfTriangleFormedByPoints(p0, p1, p2)) {
        cairo_line_to(cr, p1.x(), p1.y());
        return;
    }

    FloatPoint p1p0((p0.x() - p1.x()),(p0.y() - p1.y()));
    FloatPoint p1p2((p2.x() - p1.x()),(p2.y() - p1.y()));
    float p1p0_length = sqrtf(p1p0.x() * p1p0.x() + p1p0.y() * p1p0.y());
    float p1p2_length = sqrtf(p1p2.x() * p1p2.x() + p1p2.y() * p1p2.y());

    double cos_phi = (p1p0.x() * p1p2.x() + p1p0.y() * p1p2.y()) / (p1p0_length * p1p2_length);
    // all points on a line logic
    if (cos_phi == -1) {
        cairo_line_to(cr, p1.x(), p1.y());
        return;
    }
    if (cos_phi == 1) {
        // add infinite far away point
        unsigned int max_length = 65535;
        double factor_max = max_length / p1p0_length;
        FloatPoint ep((p0.x() + factor_max * p1p0.x()), (p0.y() + factor_max * p1p0.y()));
        cairo_line_to(cr, ep.x(), ep.y());
        return;
    }

    float tangent = radius / tan(acos(cos_phi) / 2);
    float factor_p1p0 = tangent / p1p0_length;
    FloatPoint t_p1p0((p1.x() + factor_p1p0 * p1p0.x()), (p1.y() + factor_p1p0 * p1p0.y()));

    FloatPoint orth_p1p0(p1p0.y(), -p1p0.x());
    float orth_p1p0_length = sqrt(orth_p1p0.x() * orth_p1p0.x() + orth_p1p0.y() * orth_p1p0.y());
    float factor_ra = radius / orth_p1p0_length;

    // angle between orth_p1p0 and p1p2 to get the right vector orthographic to p1p0
    double cos_alpha = (orth_p1p0.x() * p1p2.x() + orth_p1p0.y() * p1p2.y()) / (orth_p1p0_length * p1p2_length);
    if (cos_alpha < 0.f)
        orth_p1p0 = FloatPoint(-orth_p1p0.x(), -orth_p1p0.y());

    FloatPoint p((t_p1p0.x() + factor_ra * orth_p1p0.x()), (t_p1p0.y() + factor_ra * orth_p1p0.y()));

    // calculate angles for addArc
    orth_p1p0 = FloatPoint(-orth_p1p0.x(), -orth_p1p0.y());
    float sa = acos(orth_p1p0.x() / orth_p1p0_length);
    if (orth_p1p0.y() < 0.f)
        sa = 2 * piDouble - sa;

    // anticlockwise logic
    bool anticlockwise = false;

    float factor_p1p2 = tangent / p1p2_length;
    FloatPoint t_p1p2((p1.x() + factor_p1p2 * p1p2.x()), (p1.y() + factor_p1p2 * p1p2.y()));
    FloatPoint orth_p1p2((t_p1p2.x() - p.x()),(t_p1p2.y() - p.y()));
    float orth_p1p2_length = sqrtf(orth_p1p2.x() * orth_p1p2.x() + orth_p1p2.y() * orth_p1p2.y());
    float ea = acos(orth_p1p2.x() / orth_p1p2_length);
    if (orth_p1p2.y() < 0)
        ea = 2 * piDouble - ea;
    if ((sa > ea) && ((sa - ea) < piDouble))
        anticlockwise = true;
    if ((sa < ea) && ((ea - sa) > piDouble))
        anticlockwise = true;

    cairo_line_to(cr, t_p1p0.x(), t_p1p0.y());

    addArc(p, radius, sa, ea, anticlockwise);
}

void Path::addBezierCurveTo(const FloatPoint& p1, const FloatPoint& p2, const FloatPoint& ep)
{
    m_path->cubicTo(SkFloatToScalar(p1.x()), SkFloatToScalar(p1.y()),
                    SkFloatToScalar(p2.x()), SkFloatToScalar(p2.y()),
                    SkFloatToScalar(ep.x()), SkFloatToScalar(ep.y()));
}

static PassOwnPtr<Shape> createCircleShape(const FloatPoint& center, float radius)
{
    ASSERT(radius >= 0);
    return adoptPtr(new RectangleShape(FloatRect(center.x() - radius, center.y() - radius, radius*2, radius*2), FloatSize(radius, radius)));
}

void Path::addArcTo(const FloatPoint& p1, const FloatPoint& p2, float radius)
{
    m_path->arcTo(SkFloatToScalar(p1.x()), SkFloatToScalar(p1.y()),
                  SkFloatToScalar(p2.x()), SkFloatToScalar(p2.y()),
                  SkFloatToScalar(radius));
}

void Path::addArcTo(const FloatPoint& p1, const FloatPoint& p2, float radius)
{
    CGPathAddArcToPoint(m_path, 0, p1.x(), p1.y(), p2.x(), p2.y(), radius);
}

bool findIntersection(const FloatPoint& p1, const FloatPoint& p2, const FloatPoint& d1, const FloatPoint& d2, FloatPoint& intersection) 
{
    float pOffset = 0;
    float pSlope = findSlope(p1, p2, pOffset);

    float dOffset = 0;
    float dSlope = findSlope(d1, d2, dOffset);

    if (dSlope == pSlope)
        return false;
    
    if (pSlope == std::numeric_limits<float>::infinity()) {
        intersection.setX(p1.x());
        intersection.setY(dSlope * intersection.x() + dOffset);
        return true;
    }
    if (dSlope == std::numeric_limits<float>::infinity()) {
        intersection.setX(d1.x());
        intersection.setY(pSlope * intersection.x() + pOffset);
        return true;
    }
    
    // Find x at intersection, where ys overlap; x = (c' - c) / (m - m')
    intersection.setX((dOffset - pOffset) / (pSlope - dSlope));
    intersection.setY(pSlope * intersection.x() + pOffset);
    return true;
}