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#include "config.h"

#include "AffineTransform.h"

#include "IntRect.h"

#include "FloatRect.h"

#include "cairo.h"

namespace WebCore {

static const double deg2rad = 0.017453292519943295769; // pi/180

AffineTransform::AffineTransform()

{

    cairo_matrix_init_identity(&m_transform);

}

AffineTransform::AffineTransform(double a, double b, double c, double d, double tx, double ty)

{

    cairo_matrix_init(&m_transform, a, c, b, d, tx, ty);

}

AffineTransform::AffineTransform(const cairo_matrix_t &matrix)

{

    m_transform = matrix;

}

void AffineTransform::setMatrix(double a, double b, double c, double d, double tx, double ty)

{

    cairo_matrix_init(&m_transform, a, c, b, d, tx, ty);

}

void AffineTransform::map(double x, double y, double* x2, double* y2) const

{

    *x2 = x;

    *y2 = y;

    cairo_matrix_transform_point(&m_transform, x2, y2);

}

IntRect AffineTransform::mapRect(const IntRect &rect) const

{

    FloatRect floatRect(rect);

    FloatRect enclosingFloatRect = this->mapRect(floatRect);

    return enclosingIntRect(enclosingFloatRect);

}

FloatRect AffineTransform::mapRect(const FloatRect &rect) const

{

    double rectMinX = rect.x();

    double rectMaxX = rect.x() + rect.width();

    double rectMinY = rect.y();

    double rectMaxY = rect.y() + rect.height();

    double px = rectMinX;

    double py = rectMinY;

    cairo_matrix_transform_point(&m_transform, &px, &py);

    double enclosingRectMinX = px;

    double enclosingRectMinY = py;

    double enclosingRectMaxX = px;

    double enclosingRectMaxY = py;

    px = rectMaxX;

    py = rectMinY;

    cairo_matrix_transform_point(&m_transform, &px, &py);

    if (px < enclosingRectMinX) 

        enclosingRectMinX = px;

    else if (px > enclosingRectMaxX) 

        enclosingRectMaxX = px;

    if (py < enclosingRectMinY) 

        enclosingRectMinY = py;

    else if (py > enclosingRectMaxY) 

        enclosingRectMaxY = py;

    px = rectMaxX;

    py = rectMaxY;

    cairo_matrix_transform_point(&m_transform, &px, &py);

    if (px < enclosingRectMinX) 

        enclosingRectMinX = px;

    else if (px > enclosingRectMaxX)

        enclosingRectMaxX = px;

    if (py < enclosingRectMinY) 

        enclosingRectMinY = py;

    else if (py > enclosingRectMaxY) 

        enclosingRectMaxY = py;

    px = rectMinX;

    py = rectMaxY;

    cairo_matrix_transform_point(&m_transform, &px, &py);

    if (px < enclosingRectMinX) 

        enclosingRectMinX = px;

    else if (px > enclosingRectMaxX) 

        enclosingRectMaxX = px;

    if (py < enclosingRectMinY) 

        enclosingRectMinY = py;

    else if (py > enclosingRectMaxY) 

        enclosingRectMaxY = py;

    double enclosingRectWidth = enclosingRectMaxX - enclosingRectMinX;

    double enclosingRectHeight = enclosingRectMaxY - enclosingRectMinY;

    return FloatRect(enclosingRectMinX, enclosingRectMinY, enclosingRectWidth, enclosingRectHeight);

}

bool AffineTransform::isIdentity() const

{

    return ((m_transform.xx == 1) && (m_transform.yy == 1) 

         && (m_transform.xy == 0) && (m_transform.yx == 0) 

         && (m_transform.x0 == 0) && (m_transform.y0 == 0));

}

double AffineTransform::a() const

{

    return m_transform.xx;

}

void AffineTransform::setA(double a)

{

    m_transform.xx = a;

}

double AffineTransform::b() const

{

    return m_transform.xy;

}

void AffineTransform::setB(double b)

{

    m_transform.xy = b;

}

double AffineTransform::c() const

{

    return m_transform.yx;

}

void AffineTransform::setC(double c)

{

    m_transform.yx = c;

}

double AffineTransform::d() const

{

    return m_transform.yy;

}

void AffineTransform::setD(double d)

{

    m_transform.yy = d;

}

double AffineTransform::e() const

{

    return m_transform.x0;

}

void AffineTransform::setE(double e)

{

    m_transform.x0 = e;

}

double AffineTransform::f() const

{

    return m_transform.y0;

}

void AffineTransform::setF(double f)

{

    m_transform.y0 = f;

}

void AffineTransform::reset()

{

    cairo_matrix_init_identity(&m_transform);

}

AffineTransform &AffineTransform::scale(double sx, double sy)

{

    cairo_matrix_scale(&m_transform, sx, sy);

    return *this;

}

AffineTransform &AffineTransform::rotate(double d)

{

    cairo_matrix_rotate(&m_transform, d * deg2rad);

    return *this;

}

AffineTransform &AffineTransform::translate(double tx, double ty)

{

    cairo_matrix_translate(&m_transform, tx, ty);

    return *this;

}

AffineTransform &AffineTransform::shear(double sx, double sy)

{

    cairo_matrix_t shear;

    cairo_matrix_init(&shear, 1, sy, sx, 1, 0, 0);

    cairo_matrix_t result;

    cairo_matrix_multiply(&result, &shear, &m_transform);

    m_transform = result;

    return *this;

}

double AffineTransform::det() const

{

    return m_transform.xx * m_transform.yy - m_transform.xy * m_transform.yx;

}

AffineTransform AffineTransform::inverse() const

{

    if (!isInvertible()) return AffineTransform();

    cairo_matrix_t result = m_transform;

    cairo_matrix_invert(&result);

    return AffineTransform(result);

}

AffineTransform::operator cairo_matrix_t() const

{

    return m_transform;

}

bool AffineTransform::operator== (const AffineTransform &m2) const

{

    return ((m_transform.xx == m2.m_transform.xx) 

         && (m_transform.yy == m2.m_transform.yy) 

         && (m_transform.xy == m2.m_transform.xy)

         && (m_transform.yx == m2.m_transform.yx) 

         && (m_transform.x0 == m2.m_transform.x0)

         && (m_transform.y0 == m2.m_transform.y0));

}

AffineTransform &AffineTransform::operator*= (const AffineTransform &m2)

{

    cairo_matrix_t result;

    cairo_matrix_multiply(&result, &m_transform, &m2.m_transform);

    m_transform = result;

    return *this;

}

AffineTransform AffineTransform::operator* (const AffineTransform &m2)

{

    cairo_matrix_t result;

    cairo_matrix_multiply(&result, &m_transform, &m2.m_transform);

    return result;

}

}

// vim: ts=4 sw=4 et