FloatRect GraphicsContext::roundToDevicePixels(const FloatRect& rect)
{
// It is not enough just to round to pixels in device space. The rotation part of the
// affine transform matrix to device space can mess with this conversion if we have a
// rotating image like the hands of the world clock widget. We just need the scale, so
// we get the affine transform matrix and extract the scale.
CGAffineTransform deviceMatrix = CGContextGetUserSpaceToDeviceSpaceTransform(platformContext());
float deviceScaleX = sqrtf(deviceMatrix.a * deviceMatrix.a + deviceMatrix.b * deviceMatrix.b);
float deviceScaleY = sqrtf(deviceMatrix.c * deviceMatrix.c + deviceMatrix.d * deviceMatrix.d);
CGPoint deviceOrigin = CGPointMake(rect.x() * deviceScaleX, rect.y() * deviceScaleY);
CGPoint deviceLowerRight = CGPointMake((rect.x() + rect.width()) * deviceScaleX,
(rect.y() + rect.height()) * deviceScaleY);
deviceOrigin.x = roundf(deviceOrigin.x);
deviceOrigin.y = roundf(deviceOrigin.y);
deviceLowerRight.x = roundf(deviceLowerRight.x);
deviceLowerRight.y = roundf(deviceLowerRight.y);
// Don't let the height or width round to 0 unless either was originally 0
if (deviceOrigin.y == deviceLowerRight.y && rect.height() != 0)
deviceLowerRight.y += 1;
if (deviceOrigin.x == deviceLowerRight.x && rect.width() != 0)
deviceLowerRight.x += 1;
FloatPoint roundedOrigin = FloatPoint(deviceOrigin.x / deviceScaleX, deviceOrigin.y / deviceScaleY);
FloatPoint roundedLowerRight = FloatPoint(deviceLowerRight.x / deviceScaleX, deviceLowerRight.y / deviceScaleY);
return FloatRect(roundedOrigin, roundedLowerRight - roundedOrigin);
}
oop CGContextGetUserSpaceToDeviceSpaceTransform_wrap(CGContextRef c) {
CGAffineTransform ctm = CGContextGetUserSpaceToDeviceSpaceTransform(c);
objVectorOop r = Memory->objVectorObj->cloneSize(6);
r->obj_at_put(0, as_floatOop(ctm.a ), false);
r->obj_at_put(1, as_floatOop(ctm.b ), false);
r->obj_at_put(2, as_floatOop(ctm.c ), false);
r->obj_at_put(3, as_floatOop(ctm.d ), false);
r->obj_at_put(4, as_floatOop(ctm.tx), false);
r->obj_at_put(5, as_floatOop(ctm.ty), false);
return r;
}
