mirror of
https://github.com/sehugg/8bitworkshop.git
synced 2024-11-28 23:49:20 +00:00
141 lines
3.0 KiB
Plaintext
141 lines
3.0 KiB
Plaintext
|
|
$include('ntsc.ice')
|
|
|
|
// SL 2020-04-22
|
|
// A rotating texture using BRAM
|
|
|
|
// -------------------------
|
|
|
|
algorithm frame_display(
|
|
input uint10 pix_x,
|
|
input uint10 pix_y,
|
|
input uint1 pix_active,
|
|
input uint1 pix_vblank,
|
|
output! uint$color_depth$ pix_r,
|
|
output! uint$color_depth$ pix_g,
|
|
output! uint$color_depth$ pix_b
|
|
) <autorun> {
|
|
|
|
uint8 frame = 0;
|
|
uint8 angle = 0;
|
|
int20 u = 0;
|
|
int20 v = 0;
|
|
int20 cos = 0;
|
|
int20 sin = 0;
|
|
int20 cornerx = 320;
|
|
int20 cornery = 240;
|
|
//int20 cornerx = -320;
|
|
//int20 cornery = -240;
|
|
int20 corneru = 0;
|
|
int20 cornerv = 0;
|
|
int20 deltau_x = 0;
|
|
int20 deltau_y = 0;
|
|
int20 deltav_x = 0;
|
|
int20 deltav_y = 0;
|
|
int8 scale = 128;
|
|
|
|
brom uint18 tbl[$32*32$] = {
|
|
$$write_image_in_table('tile.tga',6)
|
|
};
|
|
|
|
brom int10 cosine[256] = {
|
|
$$for i=0,255 do
|
|
$math.floor(511.0 * math.cos(2*math.pi*i/255))$,
|
|
$$end
|
|
};
|
|
|
|
pix_r := 0; pix_g := 0; pix_b := 0;
|
|
// ---------- show time!
|
|
while (1) {
|
|
// display frame
|
|
while (pix_vblank == 0) {
|
|
if (pix_active) {
|
|
pix_b = tbl.rdata[0,6]<<2;
|
|
pix_g = tbl.rdata[6,6]<<2;
|
|
pix_r = tbl.rdata[12,6]<<2;
|
|
// update u,v
|
|
if (pix_x == 0) {
|
|
u = corneru;
|
|
v = cornerv;
|
|
} else {
|
|
if (pix_x == 255) {
|
|
corneru = corneru + deltau_y;
|
|
cornerv = cornerv + deltav_y;
|
|
} else {
|
|
u = u + deltau_x;
|
|
v = v + deltav_x;
|
|
}
|
|
}
|
|
// tbl bram access
|
|
tbl.addr = ((u>>11)&31) + (((v>>11)&31)<<5);
|
|
// access during loop (one cycle to go back)
|
|
}
|
|
}
|
|
// prepare next (we are in vblank, there is time)
|
|
cosine.addr = frame;
|
|
frame = frame + 1;
|
|
++:
|
|
angle = ((512+cosine.rdata) >> 2);
|
|
cosine.addr = angle;
|
|
++: // sine bram access
|
|
cos = cosine.rdata;
|
|
cosine.addr = angle + 64;
|
|
++: // sine bram access
|
|
sin = cosine.rdata;
|
|
// prepare scanline with mapping
|
|
corneru = - ((cornerx * cos) - (cornery * sin));
|
|
cornerv = - ((cornerx * sin) + (cornery * cos));
|
|
deltau_x = cos;
|
|
deltau_y = - sin;
|
|
deltav_x = sin;
|
|
deltav_y = cos;
|
|
u = corneru;
|
|
v = cornerv;
|
|
// wait for sync
|
|
while (pix_vblank == 1) {}
|
|
}
|
|
|
|
}
|
|
|
|
|
|
// -------------------------
|
|
|
|
algorithm main(
|
|
output! uint$color_depth$ video_r,
|
|
output! uint$color_depth$ video_g,
|
|
output! uint$color_depth$ video_b,
|
|
output! uint1 video_hs,
|
|
output! uint1 video_vs
|
|
)
|
|
<@clock,!reset>
|
|
{
|
|
|
|
uint1 active = 0;
|
|
uint1 vblank = 0;
|
|
uint10 pix_x = 0;
|
|
uint10 pix_y = 0;
|
|
|
|
ntsc ntsc_driver (
|
|
ntsc_hs :> video_hs,
|
|
ntsc_vs :> video_vs,
|
|
active :> active,
|
|
vblank :> vblank,
|
|
ntsc_x :> pix_x,
|
|
ntsc_y :> pix_y
|
|
);
|
|
|
|
frame_display display (
|
|
pix_x <: pix_x,
|
|
pix_y <: pix_y,
|
|
pix_active <: active,
|
|
pix_vblank <: vblank,
|
|
pix_r :> video_r,
|
|
pix_g :> video_g,
|
|
pix_b :> video_b
|
|
);
|
|
|
|
// forever
|
|
while (1) {
|
|
}
|
|
}
|