Re-implement grow from start refinement algorithm #224
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…igure_collides_with() I've hit a block: sxbp_walk_figure() currently doesn't return the line ID or pointer to the line that it's on -we kind of need this. I will add this to sxbp_walk_figure(), as it is an internal-only private-use function.
Now using this in sxbp_figure_collides_with()
Also added in a check in the walk() callback to make it stop once it plots the last line we want it to plot so far
Remove silencing of unused-parameter warnings in function
This isn't really working out, so I'm going to manually unwind this recursion iteratively, using the original implementation in solve.c for guidance
… sxbp_figure_collides_with_callback() For some reason, on line 155, we only have to quit when the line ID is GREATER than the max line requested This confused me a lot, until I realised that otherwise it was only ever plotting the first bit of the last line, so never catching collisions properly!
Once I figured out the source of my woes and corrected it, I've since been able to refactor that function nicer
Have achieved the latter by mutilating the sxbp_resolve_collision() method a little bit, but it's going to refactored anyway.
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| sxbp_line_t* line, | ||
| sxbp_co_ord_t location, | ||
| void* callback_data | ||
| ), |
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The woes experienced in sxbp_suggest_previous_length_callback() can be better alleviated by adding an additional parameter to this function which will instruct the function on whether it needs to call the callback for every single-unit step of the figure's line (i.e. every single pixel when plotting a bitmap), or if it need only call the callback for the vertices of the figure's line (i.e. every time there is a direction change). This will make it much easier for the origin coördinates of a line of a given index to be found and therefore help fix the aforementioned function. This will also allow for more optimised SVG images to be produced by the library, as an SVG rendering need only know the vertices of the figure's line, however currently a separate line segment for each 'pixel' is generated, which is very inefficient and redundant SVG.
This PR adds a new figure refinement method, a re-implementation of the original method from v0.27.0 of libsxbp, which tries extending all lines from length 1 until the shape doesn't collide.
This PR is not complete! The heavily commented sections detail the remaining work that needs to be done.
Broadly speaking, the remaining work involves completely implementing the optimisation code (currently written but unused) which allows smarter line extensions to be made in certain collision situations. This is currently blocked pending a correction of an oversight in one of its dependent functions.
The function that needs correcting is
sxbp_suggest_previous_length_callback(). Once this is done, thensxbp_suggest_previous_length()can be updated to use the actual value returned bysxbp_resolve_collision(), which it currently ignores.