mirror of https://github.com/bsnes-emu/bsnes.git
89 lines
2.0 KiB
C++
89 lines
2.0 KiB
C++
auto VDP::Sprite::write(uint9 address, uint16 data) -> void {
|
|
if(address > 320) return;
|
|
|
|
auto& object = oam[address >> 2];
|
|
switch(address.bits(0,1)) {
|
|
|
|
case 0: {
|
|
object.y = data.bits(0,8);
|
|
break;
|
|
}
|
|
|
|
case 1: {
|
|
object.link = data.bits(0,6);
|
|
object.height = 1 + data.bits(8,9) << 3;
|
|
object.width = 1 + data.bits(10,11) << 3;
|
|
break;
|
|
}
|
|
|
|
case 2: {
|
|
object.address = data.bits(0,10) << 4;
|
|
object.horizontalFlip = data.bit(11);
|
|
object.verticalFlip = data.bit(12);
|
|
object.palette = data.bits(13,14);
|
|
object.priority = data.bit(15);
|
|
break;
|
|
}
|
|
|
|
case 3: {
|
|
object.x = data.bits(0,8);
|
|
break;
|
|
}
|
|
|
|
}
|
|
}
|
|
|
|
auto VDP::Sprite::scanline(uint y) -> void {
|
|
objects.reset();
|
|
|
|
uint7 link = 0;
|
|
uint tiles = 0;
|
|
uint count = 0;
|
|
do {
|
|
auto& object = oam[link];
|
|
link = object.link;
|
|
|
|
if(128 + y < object.y) continue;
|
|
if(128 + y >= object.y + object.height) continue;
|
|
if(object.x == 0) break;
|
|
|
|
objects.append(object);
|
|
tiles += object.width >> 3;
|
|
} while(link && link < 80 && objects.size() < 20 && tiles < 40 && ++count < 80);
|
|
}
|
|
|
|
auto VDP::Sprite::run(uint x, uint y) -> void {
|
|
output.priority = 0;
|
|
output.color = 0;
|
|
|
|
for(auto& o : objects) {
|
|
if(128 + x < o.x) continue;
|
|
if(128 + x >= o.x + o.width) continue;
|
|
|
|
uint objectX = 128 + x - o.x;
|
|
uint objectY = 128 + y - o.y;
|
|
if(o.horizontalFlip) objectX = (o.width - 1) - objectX;
|
|
if(o.verticalFlip) objectY = (o.height - 1) - objectY;
|
|
|
|
uint tileX = objectX >> 3;
|
|
uint tileY = objectY >> 3;
|
|
uint tileNumber = tileX * (o.height >> 3) + tileY;
|
|
uint15 tileAddress = o.address + (tileNumber << 4);
|
|
uint pixelX = objectX & 7;
|
|
uint pixelY = objectY & 7;
|
|
tileAddress += pixelY << 1 | pixelX >> 2;
|
|
|
|
uint16 tileData = vdp.vram.read(tileAddress);
|
|
uint4 color = tileData >> (((pixelX & 3) ^ 3) << 2);
|
|
if(color) {
|
|
output.color = o.palette << 4 | color;
|
|
output.priority = o.priority;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
auto VDP::Sprite::power() -> void {
|
|
memory::fill(&io, sizeof(IO));
|
|
}
|