It looks like you forgot to copy the vital parts of the code here in your post. But anyway, what you wanna do is just trace below the player and check the texture (there are possible more alternatives but this works fine). First you need to go to your block and change the texture name of it in MED or whatever to e.g. water_tex or something else suiting, than use this code:
Code:
if (every_blabla_frame_this_reduces_fps) //optionally
{
if (c_trace(my.x, vector(my.x, my.y, my.z - 1000), IGNORE_CONTENT | IGNORE_ME | SCAN_TEXTURE) > 0)
{
if (str_cmpi(hit.texname, "water_tex") == 1)
{
//do your thing
}
}
}
