1 USING: accessors alien.data.map byte-arrays combinators grouping
2 images kernel math math.matrices.simd math.order math.vectors
3 math.vectors.simd noise random sequences typed ;
4 FROM: alien.c-types => float uchar ;
7 CONSTANT: terrain-segment-size { 512 512 }
8 CONSTANT: terrain-segment-size-vector float-4{ 512.0 512.0 1.0 1.0 }
9 CONSTANT: terrain-big-noise-scale float-4{ 0.002 0.002 0.002 0.002 }
10 CONSTANT: terrain-small-noise-scale float-4{ 0.05 0.05 0.05 0.05 }
13 { big-noise-table byte-array }
14 { small-noise-table byte-array }
15 { tiny-noise-seed integer } ;
17 : <terrain> ( -- terrain )
18 <perlin-noise-table> <perlin-noise-table>
19 32 random-bits terrain boa ;
21 : seed-at ( seed at -- seed' )
22 first2 [ >integer ] bi@ [ + ] dip [ 32 random-bits + ] curry with-seed ;
24 : big-noise-segment ( terrain at -- bytes )
25 [ big-noise-table>> terrain-big-noise-scale scale-matrix4 ] dip
26 terrain-segment-size-vector v* translation-matrix4 m4.
27 terrain-segment-size perlin-noise-image bitmap>> ; inline
28 : small-noise-segment ( terrain at -- bytes )
29 [ small-noise-table>> terrain-small-noise-scale scale-matrix4 ] dip
30 terrain-segment-size-vector v* translation-matrix4 m4.
31 terrain-segment-size perlin-noise-image bitmap>> ; inline
32 : tiny-noise-segment ( terrain at -- bytes )
33 [ tiny-noise-seed>> ] dip seed-at
34 terrain-segment-size normal-noise-image bitmap>> ; inline
35 : padding ( terrain at -- padding )
36 2drop terrain-segment-size product 255 <repetition> >byte-array ; inline
38 TUPLE: segment image ;
40 : fold-rgba-planes ( r g b a -- rgba )
41 [ vmerge-transpose vmerge-transpose ]
42 data-map( uchar-16 uchar-16 uchar-16 uchar-16 -- uchar-16[4] ) ;
44 : <terrain-image> ( big small tiny padding -- image )
48 RGBA >>component-order
49 ubyte-components >>component-type
50 terrain-segment-size >>dim ;
52 TYPED: terrain-segment ( terrain: terrain at: float-4 -- image )
55 [ small-noise-segment ]
56 [ tiny-noise-segment ]
58 } 2cleave <terrain-image> ;
60 : 4max ( a b c d -- max )
63 : mipmap ( pixels quot: ( aa ab ba bb -- c ) -- pixels' )
64 [ [ 2 <groups> ] map 2 <groups> ] dip
65 '[ first2 [ [ first2 ] bi@ @ ] 2map ] map ; inline
67 : group-pixels ( bitmap dim -- scanlines )
68 [ 4 <groups> ] [ first <groups> ] bi* ;
70 : concat-pixels ( scanlines -- bitmap )
71 [ concat ] map concat ;
73 : segment-mipmap ( image -- image' )
74 [ clone ] [ bitmap>> ] [ dim>> ] tri
75 group-pixels [ 4max ] mipmap concat-pixels >>bitmap
76 [ 2 v/n ] change-dim ;