static int _crossTwoCircles(point_t& pt1, point_t& pt2,
const point_t& c1, double r1,
const point_t& c2, double r2)
{
double d, a, b, c, p, q, r;
double cos_value[2], sin_value[2];
if (mgEquals(c1.x, c2.x) && mgEquals(c1.y, c2.y) && mgEquals(r1, r2)) {
return -1;
}
d = c1.distanceTo(c2);
if (d > r1 + r2 || d < fabs(r1 - r2)) {
return 0;
}
a = 2.0 * r1 * (c1.x - c2.x);
b = 2.0 * r1 * (c1.y - c2.y);
c = r2 * r2 - r1 * r1 - c1.distanceSquare(c2);
p = a * a + b * b;
q = -2.0 * a * c;
if (mgEquals(d, r1 + r2) || mgEquals(d, fabs(r1 - r2))) {
cos_value[0] = -q / p / 2.0;
sin_value[0] = sqrt(1 - cos_value[0] * cos_value[0]);
pt1.x = r1 * cos_value[0] + c1.x;
pt1.y = r1 * sin_value[0] + c1.y;
if (!mgEquals(pt1.distanceSquare(c2), r2 * r2)) {
pt1.y = c1.y - r1 * sin_value[0];
}
return 1;
}
r = c * c - b * b;
cos_value[0] = (sqrt(q * q - 4.0 * p * r) - q) / p / 2.0;
cos_value[1] = (-sqrt(q * q - 4.0 * p * r) - q) / p / 2.0;
sin_value[0] = sqrt(1 - cos_value[0] * cos_value[0]);
sin_value[1] = sqrt(1 - cos_value[1] * cos_value[1]);
pt1.x = r1 * cos_value[0] + c1.x;
pt2.x = r1 * cos_value[1] + c1.x;
pt1.y = r1 * sin_value[0] + c1.y;
pt2.y = r1 * sin_value[1] + c1.y;
if (!mgEquals(pt1.distanceSquare(c2), r2 * r2)) {
pt1.y = c1.y - r1 * sin_value[0];
}
if (!mgEquals(pt2.distanceSquare(c2), r2 * r2)) {
pt2.y = c1.y - r1 * sin_value[1];
}
if (mgEquals(pt1.y, pt2.y) && mgEquals(pt1.x, pt2.x)) {
if (pt1.y > 0) {
pt2.y = -pt2.y;
} else {
pt1.y = -pt1.y;
}
}
return 2;
}
float mglnrel::ptToBeeline2(
const Point2d& a, const Point2d& b, const Point2d& pt, Point2d& ptPerp)
{
// 两点重合
if (a == b)
{
ptPerp = a;
return a.distanceTo(pt);
}
// 竖直线
else if (mgEquals(a.x, b.x))
{
ptPerp.set(a.x, pt.y);
return fabsf(a.x - pt.x);
}
// 水平线
else if (mgEquals(a.y, b.y))
{
ptPerp.set(pt.x, a.y);
return fabsf(a.y - pt.y);
}
else
{
float t1 = ( b.y - a.y ) / ( b.x - a.x );
float t2 = -1.f / t1;
ptPerp.x = ( pt.y - a.y + a.x * t1 - pt.x * t2 ) / ( t1 - t2 );
ptPerp.y = a.y + (ptPerp.x - a.x) * t1;
return pt.distanceTo(ptPerp);
}
}
float MgArc::getSweepAngle() const
{
if (!mgIsZero(_sweepAngle)) {
return _sweepAngle;
}
const float midAngle = (getMidPoint() - getCenter()).angle2();
const float startAngle = getStartAngle();
const float endAngle = getEndAngle();
if (mgEquals(midAngle, startAngle) && mgEquals(startAngle, endAngle)) {
return endAngle - startAngle;
}
Tol tol(getRadius() * 1e-3f, 1e-4f);
if (getStartPoint().isEqualTo(getEndPoint(), tol)
&& (getMidPoint() + (getStartPoint() + getEndPoint()) / 2).isEqualTo(2 * getCenter(), tol)) {
return _M_2PI;
}
float startAngle2 = startAngle;
float midAngle2 = midAngle;
float endAngle2 = endAngle;
// 先尝试看是否为逆时针方向：endAngle2 > midAngle2 > startAngle2 >= 0
if (startAngle2 < 0)
startAngle2 += _M_2PI;
while (midAngle2 < startAngle2)
midAngle2 += _M_2PI;
while (endAngle2 < midAngle2)
endAngle2 += _M_2PI;
if (fabsf(startAngle2 + endAngle2 - 2 * midAngle2) < _M_PI_6
&& endAngle2 - startAngle2 < _M_2PI) {
return endAngle2 - startAngle2;
}
// 再尝试看是否为顺时针方向：endAngle2 < midAngle2 < startAngle2 <= 0
startAngle2 = startAngle;
midAngle2 = midAngle;
endAngle2 = endAngle;
if (startAngle2 > 0)
startAngle2 -= _M_2PI;
while (midAngle2 > startAngle2)
midAngle2 -= _M_2PI;
while (endAngle2 > midAngle2)
endAngle2 -= _M_2PI;
if (fabsf(startAngle2 + endAngle2 - 2 * midAngle2) < _M_PI_6) {
if (endAngle2 - startAngle2 > -_M_2PI)
return endAngle2 - startAngle2;
return mgbase::toRange(endAngle2 - startAngle2, -_M_2PI, 0);
}
return endAngle - startAngle; // error
}
static bool PtInArea_Edge(int &odd, const Point2d& pt, const Point2d& p1,
const Point2d& p2, const Point2d& p0)
{
// 如果从X方向上P不在边[P1,P2)上，则没有交点. 竖直边也没有
if (!((p2.x > p1.x) && (pt.x >= p1.x) && (pt.x < p2.x)) &&
!((p1.x > p2.x) && (pt.x <= p1.x) && (pt.x > p2.x)) )
{
return false;
}
// 求从Y负无穷大向上到P的射线和该边的交点(pt.x, yy)
float yy = p1.y + (pt.x - p1.x) * (p2.y - p1.y) / (p2.x - p1.x);
if (pt.y > yy) // 相交
{
if (mgEquals(pt.x, p1.x)) // 交点是顶点, 则比较P[i+1]和P[i-1]是否在pt.x同侧
{
if (((p0.x > pt.x) && (p2.x > pt.x)) ||
((p0.x < pt.x) && (p2.x < pt.x)) ) // 同侧
{
return false;
}
}
odd = 1 - odd; // 增加一个交点, 奇偶切换
}
return true;
}
bool GiGraphics::setPen(const GiContext* ctx)
{
bool changed = !(m_impl->ctxused & 1);
if (m_impl->canvas) {
if (ctx && (!mgEquals(ctx->getLineWidth(), m_impl->ctx.getLineWidth())
|| ctx->isAutoScale() != m_impl->ctx.isAutoScale())) {
m_impl->ctx.setLineWidth(ctx->getLineWidth(), ctx->isAutoScale());
changed = true;
}
if (ctx && ctx->getLineColor() != m_impl->ctx.getLineColor()) {
m_impl->ctx.setLineColor(ctx->getLineColor());
changed = true;
}
if (ctx && ctx->getLineStyle() != m_impl->ctx.getLineStyle()) {
m_impl->ctx.setLineStyle(ctx->getLineStyle());
changed = true;
}
}
ctx = &(m_impl->ctx);
if (m_impl->canvas && changed) {
m_impl->ctxused &= 1;
m_impl->canvas->setPen(calcPenColor(ctx->getLineColor()).getARGB(),
calcPenWidth(ctx->getLineWidth(), ctx->isAutoScale()),
ctx->getLineStyle(), 0);
}
return !ctx->isNullLine();
}
bool mgcurv::cubicSplines(
int n, const Point2d* knots, Vector2d* knotvs,
int flag, float tension)
{
bool ret = false;
if (!knots || !knotvs || n < 2)
return false;
if ((flag & cubicLoop) && n <= 512) {
float* a = new float[n * n];
ret = a && CalcCubicClosed(n, a, knotvs, knots);
delete[] a;
}
else {
float* a = new float[n * 3];
ret = a && CalcCubicUnclosed(flag, n, knots,
a, a+n, a+2*n, knotvs);
delete[] a;
}
if (!mgEquals(tension, 1.f)) {
for (int i = 0; i < n; i++) {
knotvs[i].x *= tension;
knotvs[i].y *= tension;
}
}
return ret;
}
float MgArc::getSweepAngle() const
{
const float midAngle = (getMidPoint() - getCenter()).angle2();
const float startAngle = getStartAngle();
const float endAngle = getEndAngle();
if (mgEquals(midAngle, startAngle) && mgEquals(startAngle, endAngle)) {
return endAngle - startAngle;
}
float startAngle2 = startAngle;
float midAngle2 = midAngle;
float endAngle2 = endAngle;
// 先尝试看是否为逆时针方向：endAngle2 > midAngle2 > startAngle2 >= 0
if (startAngle2 < 0)
startAngle2 += _M_2PI;
while (midAngle2 < startAngle2)
midAngle2 += _M_2PI;
while (endAngle2 < midAngle2)
endAngle2 += _M_2PI;
if (fabsf(startAngle2 + endAngle2 - 2 * midAngle2) < _M_PI_6
&& endAngle2 - startAngle2 < _M_2PI) {
return endAngle2 - startAngle2;
}
// 再尝试看是否为顺时针方向：endAngle2 < midAngle2 < startAngle2 <= 0
startAngle2 = startAngle;
midAngle2 = midAngle;
endAngle2 = endAngle;
if (startAngle2 > 0)
startAngle2 -= _M_2PI;
while (midAngle2 > startAngle2)
midAngle2 -= _M_2PI;
while (endAngle2 > midAngle2)
endAngle2 -= _M_2PI;
if (fabsf(startAngle2 + endAngle2 - 2 * midAngle2) < _M_PI_6) {
if (endAngle2 - startAngle2 > -_M_2PI)
return endAngle2 - startAngle2;
return mgToRange(endAngle2 - startAngle2, -_M_2PI, 0);
}
return endAngle - startAngle; // error
}
bool GiGraphics::_drawPolygon(const GiContext* ctx, int count, const Point2d* points,
bool m2d, bool fill, bool edge, bool modelUnit)
{
GiContext context (ctx ? *ctx : m_impl->ctx);
if (!edge)
context.setNullLine();
if (!fill)
context.setNoFillColor();
if (context.isNullLine() && !context.hasFillColor())
return false;
vector<Point2d> pxpoints;
Point2d pt1, pt2;
Matrix2d matD(S2D(xf(), modelUnit));
pxpoints.resize(count);
Point2d *pxs = &pxpoints.front();
int n = 0;
for (int i = 0; i < count; i++) {
pt2 = points[i];
if (m2d)
pt2 *= matD;
if (i == 0 || count <= 4
|| fabsf(pt1.x - pt2.x) > 2
|| fabsf(pt1.y - pt2.y) > 2) {
pt1 = pt2;
pxs[n++] = pt1;
}
}
if (n == 4 && m2d
&& mgEquals(pxs[0].x, pxs[3].x) && mgEquals(pxs[1].x, pxs[2].x)
&& mgEquals(pxs[0].y, pxs[1].y) && mgEquals(pxs[2].y, pxs[3].y))
{
Box2d rc(pxs[0].x, pxs[0].y, pxs[2].x, pxs[2].y, true);
return rawRect(&context, rc.xmin, rc.ymin, rc.width(), rc.height());
}
return rawPolygon(&context, pxs, n);
}
bool GiGraphics::setPen(const GiContext* ctx)
{
bool changed = !(m_impl->ctxused & 1);
if (m_impl->canvas) {
if (ctx && (!mgEquals(ctx->getLineWidth(), m_impl->ctx.getLineWidth())
|| ctx->isAutoScale() != m_impl->ctx.isAutoScale())) {
m_impl->ctx.setLineWidth(ctx->getLineWidth(), ctx->isAutoScale());
changed = true;
}
if (ctx && !mgEquals(ctx->getExtraWidth(), m_impl->ctx.getExtraWidth())) {
m_impl->ctx.setExtraWidth(ctx->getExtraWidth());
changed = true;
}
if (ctx && ctx->getLineColor() != m_impl->ctx.getLineColor()) {
m_impl->ctx.setLineColor(ctx->getLineColor());
changed = true;
}
if (ctx && ctx->getLineStyleEx() != m_impl->ctx.getLineStyleEx()) {
m_impl->ctx.setLineStyle(ctx->getLineStyleEx(), true);
changed = true;
}
}
ctx = &(m_impl->ctx);
if (m_impl->canvas && changed) {
m_impl->ctxused &= 1;
float w = calcPenWidth(ctx->getLineWidth(), ctx->isAutoScale());
float orgw = ctx->getLineWidth();
orgw = (orgw < -0.1f && ctx->isAutoScale()) ? orgw - 1e4f : orgw;
m_impl->canvas->setPen(calcPenColor(ctx->getLineColor()).getARGB(),
w + ctx->getExtraWidth(),
ctx->getLineStyleEx(),
mgMax(m_impl->phase, 0.f), orgw);
}
return !ctx->isNullLine();
}
bool GiTransform::zoomByFactor(float factor, const Point2d* pxAt, bool adjust)
{
float scale = m_impl->viewScale;
if (factor > 0)
scale *= (1.f + fabsf(factor));
else
scale /= (1.f + fabsf(factor));
if (adjust) {
scale = mgMax(scale, m_impl->minViewScale);
scale = mgMin(scale, m_impl->maxViewScale);
}
if (mgEquals(scale, m_impl->viewScale))
return false;
return zoomScale(scale, pxAt, adjust);
}
bool zoomNoAdjust(const Point2d& pnt, float scale, bool* changed = NULL)
{
bool bChanged = false;
if (pnt != centerW || !mgEquals(scale, viewScale))
{
tmpCenterW = pnt;
tmpViewScale = scale;
bChanged = true;
if (zoomEnabled) {
centerW = pnt;
viewScale = scale;
updateTransforms();
zoomChanged();
}
}
if (changed != NULL)
*changed = bChanged;
return bChanged;
}
bool Matrix2d::isIdentity() const
{
return mgEquals(m11, 1.f) && mgIsZero(m12)
&& mgEquals(m22, 1.f) && mgIsZero(m21)
&& mgIsZero(dx) && mgIsZero(dy);
}
bool MgBaseRect::isOrtho() const
{
return mgEquals(_points[1].y, _points[0].y);
}
bool MgRoundRect::_equals(const MgRoundRect& src) const
{
return mgEquals(_rx, src._rx)
&& mgEquals(_ry, src._ry)
&& __super::_equals(src);
}