spr

spr(id, x, y, [colorkey=-1], [scale=1], [flip=0], [rotate=0], [w=1], [h=1])

Parameters

• id : index of the sprite (0..511)
• x, y : screen coordinates of top left corner of sprite.
• colorkey : index (or array of indexes) of the color in the sprite that will be used as transparent color. Use -1 if you want an opaque sprite.
• scale : scale factor applied to sprite.
• flip : flip the sprite vertically or horizontally or both.
• rotate : rotate the sprite by 0, 90, 180 or 270 degrees.
• w : width of composite sprite
• h : height of composite sprite

Description

Draws the sprite number index at the x and y coordinate.

You can specify a colorkey in the palette which will be used as the transparent color or use a value of -1 for an opaque sprite.

The sprite can be scaled up by a desired factor. For example, a scale factor of 2 means an 8x8 pixel sprite is drawn to a 16x16 area of the screen. Fractional factors are floored to integers, and both a factor of 0 and negative factors cause the sprite to not get drawn.

You can flip the sprite where:

• 0 = No Flip
• 1 = Flip horizontally
• 2 = Flip vertically
• 3 = Flip both vertically and horizontally

When you rotate the sprite, it's rotated clockwise in 90° steps:

• 0 = No rotation
• 1 = 90° rotation
• 2 = 180° rotation
• 3 = 270° rotation

Important: If you combine flip and rotate in the same sprite, take into account that rotate is applied prior to flip (the order matters).

You can draw a composite sprite (consisting of a rectangular region of sprites from the sprite sheet) by specifying the w and h parameters (which default to 1).

Example

-- spr demo

--Build sprite from text
data = "D000000D" .. "D0C00C0D" ..
  "DDDDDDDD" .. "DDCDDD2D" ..
  "DCCCDDDD" .. "DDcdd2dd" ..
  "DDDDDDDD" .. "EEEEEEEE"
for i=0,64 do
 poke4(0x4000*2+64+i,
  tonumber(string.sub(
  data,i+1,i+1),16))
end

p={
 x={val=100,min=0,max=240},
 y={val=68,min=0,max=136},
 colorkey={val=0,min=-1,max=15},
 scale={val=1,min=0,max=256},
 flip={val=0,min=0,max=3},
 rotate={val=0,min=0,max=3},
}
sel=next(p,nil)


function TIC()

 --Keys
 if btnp(0,30,6) then
  for n=0,4 do
   sel=next(p,sel) or next(p,nil)
  end
 end
 if btnp(1,30,6) then
  sel=next(p,sel) or next(p,nil)
 end

 if btnp(2,30,6) then
  p[sel].val=p[sel].val-1
 end
 if btnp(3,30,6) then
  p[sel].val=p[sel].val+1
 end

 --Clamp
 if p[sel].val>p[sel].max then
   p[sel].val=p[sel].max
 end
 if p[sel].val<p[sel].min then
   p[sel].val=p[sel].min
 end

 cls(0)
 print("Use up/down  to select parameter",0,0)
 print("left/right to change its value:",0,10)

 --Build menu with cursor
 r=0
 for k,v in pairs(p) do
  cur=(k==sel) and '>' or ' '
  print(cur..k..':'..v.val,0,30+10*r)
  r=r+1
 end

 --Draw Sprite
 spr(1,
    p.x.val,
    p.y.val,
    p.colorkey.val,
    p.scale.val,
    p.flip.val,
    p.rotate.val)

end

Color Swapping Sprites

You can substitute one color of the palette for another to use an alternative version of a sprite or tile.

Tip

Make sure to set the palette back to how it was afterwards.

initial_color=12 --initial color of your sprite you want to change
new_color=3 --color you want to use
poke4(0x3FF0*2+initial_color,new_color) -- set new_color in place of initial_color
spr(...)
poke4(0x3FF0*2+initial_color,initial_color) -- change it back