* LineVirtualIterator
Proposal of LineVirtualIterator, an alternative to "LineIterator not attached to any mat".
This is basically the same implementation, replacing the address difference by a single "offset" variable. elemsize becomes irrelevant and considered to be 1. "step" is thus equal to size.width since no stride is expected.
* Update drawing.cpp
fixed warning
* improvement of LineVirtualIterator
instead of being too conservative, the new implementation gets rid of "offset/step" and only keeps a "Point currentPos" up to date.
left_to_right is renamed to forceLeftToRight as suggested (even for the old LineIterator)
assert() replaced by CV_Assert() (even for the old LineIterator)
* fixed implementation
+fixed last commit so that LineVirtualIterator gives at least the same results as LineIterator
+added a new constructor that does not require any Size, so that no clipping is done and iteration occurs from pt1 to pt2. This is done by adding a spatial offset to pt1 and pt2 so that the same implementation is used, the size being in that case the spatial size between pt1 and pt2
* Update imgproc.hpp
fixed warnings
* Update drawing.cpp
fixed whitespace
* Update drawing.cpp
trailing whitespace
* Update imgproc.hpp
+added a new constructor that takes a Rect rather than a Size. It computes the line pt1->pt2 that clips that rect.
Yet again, this is still based on the same implementation, thanks to the Size and the currentPosOffset that can artifically consider the origin of the rect at (0,0)
* revert changes
revert changes on original LineIterator implementation, that will be superseded by the new LineVirtualIterator anyway
* added test of LineVirtualIterator
* More tests
* refactoring
Use C++11 chained constructors
Improved code style
* improve test
Added offset as random test data.
* fixed order of initialization
* merged LineIterator and VirtualLineIterator
* merged LineIterator & VirtualLineIterator
* merged LineIterator & VirtualLineIterator
* merged LineIterator & VirtualLineIterator
* made LineIterator::operator ++() more efficient
added one perfectly predictable check; in theory, since ptmode is set in the end of the constructor in the header file, the compiler can figure out that it's always true/false and eliminate the check from the inline `LineIterator::operator++()` completely
* optimized Line() function
in the most common case (CV_8UC3) eliminated the check from the loop
Co-authored-by: Vadim Pisarevsky <vadim.pisarevsky@gmail.com>
* LineIterator witout a Mat
cv::LineIterator can be used without being attached to any cv::Mat, it only needs the size and type of data. An alternative constructor has been defined for that.
In that case, a LineIterator can no more be dereferenced with the * operator, but pos() still returns valid pixel positions.
It can be useful when LineIterator is just used to compute positions of pixels on a line, without requiring to build a Mat just for that.
Use case : with a dataset that would represent a huge image, pixel positions can be pre-computed before querying the dataset API.
* Update imgproc.hpp
removed trailing spaces
* Update drawing.cpp
fixed warning
added 64b optimization for 3 channels case
not added 64b optimization for 4 channels case since timings did not
show any improvement
split ICV_HLINE cases into inline functions instead of macro for code
size reduction, without significand speed drawback at first sight
