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bilerp collision height

Joe Groff 2009-05-09 11:36:24 -05:00
parent 89ee4b1f40
commit e12a050563
1 changed files with 18 additions and 6 deletions
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extra/terrain/terrain.factor
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@ -137,12 +137,25 @@ TUPLE: terrain-world < world
: apply-gravity ( velocity -- velocity' ) : apply-gravity ( velocity -- velocity' )
1 over [ GRAVITY - ] change-nth ; 1 over [ GRAVITY - ] change-nth ;
: pixel ( coords dim -- index ) :: pixel-indices ( coords dim -- indices )
[ drop first ] [ [ second ] [ first ] bi* * ] 2bi + ; coords vfloor [ >integer ] map :> floor-coords
floor-coords first2 dim first * + :> base-index
base-index dim first + :> next-row-index
: terrain-height-at ( segment point -- height ) base-index
over dim>> [ v* vfloor ] [ pixel >integer ] bi base-index 1 +
swap bitmap>> 4 <groups> nth COMPONENT-SCALE v. 255.0 / ; next-row-index
next-row-index 1 + 4array ;
:: terrain-height-at ( segment point -- height )
segment dim>> :> dim
dim point v* :> pixel
pixel dup vfloor v- :> pixel-mantissa
segment bitmap>> 4 <groups> :> pixels
pixel dim pixel-indices :> indices
indices [ pixels nth COMPONENT-SCALE v. 255.0 / ] map
first4 [ pixel-mantissa first lerp ] 2bi@ pixel-mantissa second lerp ;
: collide ( segment location -- location' ) : collide ( segment location -- location' )
[ [ first ] [ third ] bi 2array terrain-height-at PLAYER-HEIGHT + ] [ [ first ] [ third ] bi 2array terrain-height-at PLAYER-HEIGHT + ]
@ -152,7 +165,6 @@ TUPLE: terrain-world < world
: tick-player ( world player -- ) : tick-player ( world player -- )
[ apply-friction apply-gravity ] change-velocity [ apply-friction apply-gravity ] change-velocity
dup velocity>> [ v+ [ terrain-segment>> ] dip collide ] curry with change-location dup velocity>> [ v+ [ terrain-segment>> ] dip collide ] curry with change-location
P
drop ; drop ;
M: terrain-world tick* M: terrain-world tick*