Option explicit
Option default integer

Option console serial
CLS
Dim trans%=9,cutoff%=20
Sprite set transparent 9
drawboard
Const a=1,b=2,c=3,d=4,e=5,f=6,g=7,h=8
Const movedistance=2
Const whiteking= 1
Const whitequeen= 2
Const whiterook= 3
Const whiterook2= 4
Const whitebishop= 5
Const whitebishop2= 6
Const whiteknight= 7
Const whiteknight2= 8
Const whitepawn= 9
Const whitepawn2= 10
Const whitepawn3= 11
Const whitepawn4= 12
Const whitepawn5= 13
Const whitepawn6= 14
Const whitepawn7= 15
Const whitepawn8= 16
Const blackking= 21
Const blackqueen= 22
Const blackrook= 23
Const blackrook2= 24
Const blackbishop= 25
Const blackbishop2= 26
Const blackknight= 27
Const blackknight2= 28
Const blackpawn= 29
Const blackpawn2= 30
Const blackpawn3= 31
Const blackpawn4= 32
Const blackpawn5= 33
Const blackpawn6= 34
Const blackpawn7= 35
Const blackpawn8= 36
Data whiterook,whiteknight,whitebishop,whitequeen,whiteking,whitebishop2,whiteknight2,whiterook2
Data whitepawn,whitepawn2,whitepawn3,whitepawn4,whitepawn5,whitepawn6,whitepawn7,whitepawn8
Data 0,0,0,0,0,0,0,0
Data 0,0,0,0,0,0,0,0
Data 0,0,0,0,0,0,0,0
Data 0,0,0,0,0,0,0,0
Data blackpawn,blackpawn2,blackpawn3,blackpawn4,blackpawn5,blackpawn6,blackpawn7,blackpawn8
Data blackrook,blackknight,blackbishop,blackqueen,blackking,blackbishop2,blackknight2,blackrook2
Dim board(8,8)
Dim x,y
For y=1 To 8
 For x=1 To 8
   Read board(x,y)
 Next x
Next y
Const leftedge=(MM.HRes-MM.VRes)/2,square=48
'Load jpg "fpgJx",100,0
Sprite loadpng whitequeen,"whitequeen48",trans%,cutoff%
Sprite loadpng whiteking,"whiteking48",trans%,cutoff%
Sprite loadpng whitebishop,"whitebishop48",trans%,cutoff%
Sprite copy whitebishop,whitebishop2,1
Sprite loadpng whiterook,"whiterook48",trans%,cutoff%
Sprite copy whiterook, whiterook2,1
Sprite loadpng whiteknight,"whiteknight48",trans%,cutoff%
Sprite copy whiteknight,whiteknight2,1
Sprite loadpng whitepawn,"whitepawn48",trans%,cutoff%
Sprite copy whitepawn, whitepawn2,7
Sprite loadpng blackqueen,"blackqueen48",trans%,cutoff%
Sprite loadpng blackking,"blackking48",trans%,cutoff%
Sprite loadpng blackbishop,"blackbishop48",trans%,cutoff%
Sprite copy blackbishop,blackbishop2,1
Sprite loadpng blackrook,"blackrook48",trans%,cutoff%
Sprite copy blackrook,blackrook2,1
Sprite loadpng blackknight,"blackknight48",trans%,cutoff%
Sprite copy blackknight,blackknight2,1
Sprite loadpng blackpawn,"blackpawn48",trans%,cutoff%
Sprite copy blackpawn,blackpawn2,7
For y=1 To 8
 For x=1 To 8
   If board(x,y) Then place board(x,y),x,y
 Next x
Next y


movepiece e,2,e,4
movepiece c,7,c,5
movepiece g,1,f,3
movepiece d,7,d,6
movepiece d,2,d,4
movepiece c,5,d,4
movepiece f,3,d,4
movepiece g,8,f,6
movepiece b,1,c,3
movepiece b,8,c,6
movepiece c,1,g,5
movepiece e,7,e,6
movepiece d,1,d,2
movepiece a,7,a,6
movepiece e,1,c,1
movepiece h,7,h,6
movepiece g,5,f,6
movepiece d,8,f,6
movepiece f,1,c,4
movepiece f,8,e,7
movepiece d,4,c,6
movepiece b,7,c,6
movepiece f,2,f,4
movepiece e,8,g,8
movepiece c,4,d,3
movepiece c,8,b,7
movepiece d,3,c,4
movepiece b,7,c,8
movepiece d,2,d,3

End
'
Sub movepiece(x1,y1,x2,y2)
 If board(x1,y1)=0 Then Exit Sub
 Local w=sprite(W,board(x1,y1))
 Local xold=(x1-1)*square+leftedge+square\2-w\2
 Local yold=(8-y1)*square-3
 Local xnew=(x2-1)*square+leftedge+square\2-w\2
 Local ynew=(8-y2)*square-3
 Local float angle=Deg(Atan2(yold-ynew,xold-xnew))-90
 vector 0,angle,0,xold,yold
 Local float distancetomove=Sqr((xold-xnew)^2 + (yold-ynew)^2)
 Do While distancetomove>movedistance
   vector 0,angle,movedistance,xold,yold
   If board(x2,y2)<>0 And distancetomove<square Then
       Sprite hide board(x2,y2)
       board(x2,y2)=0
   EndIf
   FRAMEBUFFER wait
   Sprite show board(x1,y1),xold,yold,1
   distancetomove=distancetomove-movedistance
 Loop
 If Abs(x1-x2)=2 And (board(x1,y1)=blackking Or board(x1,y1)=whiteking) Then 'castle
   If x2=c Then movepiece a,y1,d,y1
   If x2=g Then movepiece h,y1,f,y1
 EndIf
 board(x2,y2)=board(x1,y1)
 board(x1,y1)=0
 place board(x2,y2),x2,y2
 FRAMEBUFFER wait
End Sub
'
Sub place(n,x,y)
 Local w=sprite(W,n)
 Local xoff=(x-1)*square+leftedge+square\2-w\2
 Local yoff=(8-y)*square-3
 Sprite show n,xoff,yoff,1
End Sub
'
Sub vector(obj As integer, angle As float, distance As float, x_new As integer, y_new As integer)
 Static float y_move(9), x_move(9)
 Static float x_last(9), y_last(9)
 Static float last_angle(9)=(-1,-1,-1,-1,-1,-1,-1,-1,-1,-1)
 If distance=0 Then
   x_last(obj)=x_new
   y_last(obj)=y_new
 EndIf
 If angle<>last_angle(obj) Then
   y_move(obj)=-Cos(Rad(angle))
   x_move(obj)=Sin(Rad(angle))
   last_angle(obj)=angle
 EndIf
 x_last(obj) = x_last(obj) + distance * x_move(obj)
 y_last(obj) = y_last(obj) + distance * y_move(obj)
 x_new=Cint(x_last(obj))
 y_new=Cint(y_last(obj))
End Sub

Sub drawboard
MODE 3
Map(14)=&HCFB095
Map(13)=&H7B3F00
Map set
Local x%,y%
Local left%=(MM.HRes-MM.VRes)/2
Local h%=MM.VRes\8

For x%=left%+h% To left%+h%*8-1 Step h%*2
 For y%=0 To left%+h%*8-1 Step h%*2
   Box x%,y%,h%,h%,0,Map(14),Map(14)
 Next y%
Next x%
For x%=left% To left%+h%*8-1 Step h%*2
 For y%=h% To left%+h%*8-1 Step h%*2
   Box x%,y%,h%,h%,0,Map(14),Map(14)
 Next y%
Next x%
For x%=left%+h% To left%+h%*8-1 Step h%*2
 For y%=h% To left%+h%*8-1 Step h%*2
   Box x%,y%,h%,h%,0,Map(13),Map(13)
 Next y%
Next x%
For x%=left% To left%+h%*8-1 Step h%*2
 For y%=0 To left%+h%*8-1 Step h%*2
   Box x%,y%,h%,h%,0,Map(13),Map(13)
 Next y%
Next x%
End Sub

#if !(PICO_DOUBLE_SUPPORT_ROM_V1 && PICO_RP2040_B0_SUPPORTED)
static __attribute__((noreturn)) void missing_double_func_shim(void) {
   panic("missing double function");
}
#endif