If you are using a shallow ramp (say, a change in height of 1/2 the icon_height), it is possible to fall through one of the ramp pieces.
Numbered Steps to Reproduce Problem:
1. Create two ramps at ~25 degree inclination, one from 0 to 1/2 icon_height, and the second from 1/2 icon_height to 1 icon_height
2. Place ramps next to eachother
3. Slowly walk along these ramps in both directions and both ramp directions (upwards towards left and upwards towards right)
Code Snippet (if applicable) to Reproduce Problem:
Your mob does not fall through the higher ramp
Your mob interacts with both ramps, and if the lower ramp is the last one to be iterated through in the ramp check, the lower ramp's height will override the higher ramp's height, causing your mob to fall through the higher ramp.
Does the problem occur:
Every time? Or how often?
In other games?
In other user accounts?
On other computers?
When does the problem NOT occur?
In certain map layouts where the lower ramp is iterated through before the higher ramp.
Did the problem NOT occur in any earlier versions? If so, what was the last version that worked? (Visit http://www.byond.com/download/build to download old versions for testing.)
Replacing line 294 in pixel-movement.dm with
move_y = max(move_y,h - py)
This may cause other problems with interacting ramps.