I believe that there may be differences in some of the entries in the left-right movement table (the equivalent of the table at #8421 in JSW1) in the JSW2 game engine, which have the result that if Willy is facing rightwards and you press left (or vice versa), then he doesn't just turn around but his animation-frame is also incremented at the same time.
This allows him to jump leftwards and then rightwards in quick succession (whereas in JSW1 if you try to do that, he will turn around upon landing but do a vertical jump before performing the jump back the way he came from).
One way to get around this effect in the 'Priest's Hole' scenario is to have Willy standing on the edge of the platform facing away
from the direction he is about to jump, and then press the 'opposite left-right' key and Jump key simultaneously. Then he will turn around and jump without
falling off his precarious perch!
However, this 'turn around and move at the same time' effect doesn't
explain what is going on in my 'JSW2 New Quirky Feature' test file. If you move Willy into the bottom-right corner, facing right, then press Left+Jump simultaneously (so that he turns around but starts the jump from as far right a position as possible), then he still jumps all the way over the pillar and falls down into the hole on the other side.
Conversely, in the test file based on the JSW1 game engine, you can walk Willy all the way up to the two-high Earth block pillar (facing it and touching it), and then jump up onto it without
him falling down into the hole on the far side - he lands on top of the pillar, one animation-frame short of falling past it.
During my earlier experimentation, playing around with the jumping routine in JSW1, I managed to recreate the bahaviour seen in JSW2, in my 'Jump Code rewrite' test file (http://jswmm.co.uk/t...ge-20#entry8311
). In fact, I came up with that test file, and discovered the 'different' jumping outcomes, before
I spotted the similar behaviour manifesting itself in JSW2.
I believe that the difference in the JSW2 jumping behaviour may arise because in each time-frame of a jump, the check for a solid underfoot platform (to curtail the descent phase of a jump) takes place before
Willy's y-coordinate is incremented downwards.*
Whereas in the JSW1 game engine, he is moved downwards during a jump before
the check for underfoot behaviour takes place. That, I believe, is the fundamental reason why Willy can jump into supposedly solid blocks.
So really, it is the JSW1 jumping that is the illogical and quirky behaviour - Willy shouldn't
be able to jump up onto a two-block high wall (such as you get in 'Banyan Tree') unless he takes several steps back from it before taking the jump. I'll try to create a few frame-by-frame screenshots later to illustrate exactly why that is the case.
(*EDIT: Either that, or both vertical AND horizontal incrementations of Willy are performed in JSW2 before a check for underfoot platforms is made - actually, that might explain why Willy is able to jump into the slots in 'Wine Cellar' without his head entering an Earth block on the way down.)