Segment Query (raycasting) API requests

[ShiftZ]

Yes, i've found that bug and fixed. But problem decribed above still present. Try demo modification, if it will work for ?

[slembcke]

Hmm. I remember that coming up and thought I added the change to trunk. Apparently I didn't.

[ShiftZ]

[ShiftZ]

Also, you do not checking last cell while traverse.

while(next_h < 1.0f || next_v < 1.0f)

this prevent performing quering when next_h and next_v is out of range. But they should be out of range in last cell. And if first is last , then we miss quering totally.

Adding

int index = hash_func(cell_x, cell_y, n);
query(hash, hash->table[index], obj, func, data);

after while block fixes this problem.

[ShiftZ]

With these two fixes it works fine.

[slembcke]

Very good catch. I actually did know that from working on some procedural noise code once. I guess I never put the two together though.

I commited those changes and am still able to get it to miss raycasts:
http://files.slembcke.net/temp/screensh ... 154204.png

I know there were some bugs that caused it to miss raycasts that happened along the x and y axis before, but haven't had the time to figure out why.

Thank you very much for your help so far. I know that this is a feature that other people really want, but I just haven't had the time with contracting work and trying to develop our own games lately to finish it properly.

[ShiftZ]

Implemented bullets with raycasting, and it works fine for me, no misses.
I can share a file to you.

[slembcke]

Fixed the missed raycasts that I was talking about. It was only an issue when the start point was on a grid point and the direction was very close to horizontal or vertical but biased in the positive direction of the minor direction axis... If that made any sense. Ultimately it just came down to replacing a ceil(value) with a floor(value + 1). I think the raycasting code is functionally complete and hopefully mostly bug free!

The next item to do is implement an early exit when you only want the first object hit along a long ray. Right now it finds all hits and returns only the earliest one.

[slembcke]

[slembcke]

Hah. I had thought I simplified the terminating condition for the grid traversal, but I ended up just re-adding the bug that ShiftZ pointed out. It's actually fixed and simplified now. Whoops.