prog8/examples/cx16/sprites/dragons.p8

59 lines
2.3 KiB
Lua

%import diskio
%import textio
%import sprites
%zeropage basicsafe
%option no_sysinit
; an example that displays and then moves many sprites at once.
main {
; we choose arbitrary unused vram location for sprite data: $12000
const ubyte SPRITE_DATA_BANK = 1
const uword SPRITE_DATA_ADDR = $2000
const ubyte SPRITE_PALETTE_OFFSET = 1 ; sprite palette at color index 16
const ubyte NUM_DRAGONS = 25
word[NUM_DRAGONS*2] xpositions
word[NUM_DRAGONS*2] ypositions
sub start() {
txt.plot(30,30)
txt.print("there be many dragons!")
; load the sprite data and color palette directly into Vera ram
void diskio.vload_raw("dragonsprite.bin", SPRITE_DATA_BANK, SPRITE_DATA_ADDR)
void diskio.vload_raw("dragonsprite.pal", 1, $fa00 + SPRITE_PALETTE_OFFSET*16*2)
; initialize the dragon sprites (every dragon needs 2 sprites, top and bottom half)
ubyte sprite_num
for sprite_num in 0 to NUM_DRAGONS*2-2 step 2 {
sprites.init(sprite_num+1, SPRITE_DATA_BANK, SPRITE_DATA_ADDR, sprites.SIZE_64, sprites.SIZE_64, sprites.COLORS_16, SPRITE_PALETTE_OFFSET)
sprites.init(sprite_num+2, SPRITE_DATA_BANK, SPRITE_DATA_ADDR + 64*64/2, sprites.SIZE_64, sprites.SIZE_64, sprites.COLORS_16, SPRITE_PALETTE_OFFSET)
xpositions[sprite_num] = math.rndw() % (640-64) as word
xpositions[sprite_num+1] = xpositions[sprite_num]
ypositions[sprite_num] = sprite_num * $0008 as word
ypositions[sprite_num+1] = ypositions[sprite_num]+64
}
repeat {
; move all dragons (remember each one consists of a top and a bottom sprite)
for sprite_num in 0 to NUM_DRAGONS*2-2 step 2 {
xpositions[sprite_num]++
xpositions[sprite_num+1]++
if sprite_num & 2 !=0 {
xpositions[sprite_num]++
xpositions[sprite_num+1]++
}
if xpositions[sprite_num] >= 640
xpositions[sprite_num] = -64
if xpositions[sprite_num+1] >= 640
xpositions[sprite_num+1] = -64
}
sys.waitvsync()
sprites.pos_batch(1, NUM_DRAGONS*2, &xpositions, &ypositions)
}
}
}