Rotating some points , seems slow

[slenkar]

I was going to make a vector graphics game like asteroids but different
I rotated some points around an origin but even that seems too slow

I was going to draw lines between the points

Code:

#include <FSin.bas>


Dim trishipx(12) as UByte
Dim trishipy(12) as UByte
Dim drawtrishipx(12) as UByte
dim drawtrishipy(12) as UByte


trishipx(0)=62
trishipy(0)=58

trishipx(1)=58
trishipy(1)=58

trishipx(2)=58
trishipy(2)=62

trishipx(3)=58
trishipy(3)=54

trishipx(4)=60
trishipy(4)=58

trishipx(5)=60
trishipy(5)=62

Dim trishipangle as Integer

Function rotate(degrees as Integer) as Integer
dim transformedX as Ubyte=0
dim transformedY as ubyte=0
dim pointx as Ubyte=54
dim pointy as Ubyte=54
  for  x=0 to 5
'Local theta:Float=1
transformedX= fCos(degrees) * (trishipx(x)-pointx) - fSin(degrees) * (trishipy(x)-pointy) + pointx
transformedY = fSin(degrees) * (trishipx(x)-pointx) + fCos(degrees) * (trishipy(x)-pointy) + pointy
drawtrishipx(x) = transformedX
drawtrishipy(x) = transformedY
Next
return 1
End Function

Function drawship() as Integer


for x=0 to 5
plotPoint(drawtrishipx(x),drawtrishipy(x))
next

return 1
End Function

While 1


trishipangle=trishipangle+1
if trishipangle>360 then
trishipangle=0
end if


rotate(trishipangle)

drawship()

Wend



SUB plotPoint (x as uByte, y as uByte)
ASM
ld d,(IX+5) ;'X
ld e,(IX+7) ;'Y

    ld a, 191
   sub e  
   ret c  
   ld e, a  
   and a  
  
    rra      
   scf      
   rra      
   and a  
   rra      
   xor e        
   and 248
   xor e
   ld h, a
   ld a, d
   rlca
   rlca
   rlca
   xor e
   and 199
   xor e
   rlca
   rlca
   ld l, a
  
    ld a, d
   and 7
   ld b, a
   inc b
   ld a, 1
  
    plotPoint_loop:
        rrca
   djnz plotPoint_loop  
   ;cpl
    ld b, a  
   ld a, (hl)
   or b  
   ld (hl), a
  
END ASM
END SUB