public static List <Roller> Create(BitArray walls, int mapWidth, int x, int y, int dir, int startTime, int period, int speed = 0xC0)
{
Roller roller = new Roller();
dir *= 0x2000;
roller.vx = KuruMath.instance.sin(speed * 0x100, (short)dir);
roller.vy = -KuruMath.instance.cos(speed * 0x100, (short)dir);
roller.x = (short)(x * 8 + 16);
if ((dir & 0x2000) != 0)
{
roller.x -= 8;
}
roller.y = (short)(y * 8 + 16);
roller.startTime = (ushort)startTime;
// Roll through the level until it collides with something
int colxoffs = KuruMath.instance.sin(15, (short)dir);
int colyoffs = -KuruMath.instance.cos(15, (short)dir);
int xpos = roller.x << 16;
int ypos = roller.y << 16;
int t = 0;
bool isPixelInCollision(int xm, int ym)
{
int addr = xm + ym * mapWidth;
return(walls[addr]);
}
while (true)
{
xpos += roller.vx;
ypos += roller.vy;
if (isPixelInCollision((xpos >> 16) + colxoffs, (ypos >> 16) + colyoffs))
{
break;
}
t++;
}
int minx = Math.Min(roller.x, xpos >> 16) - 14;
int miny = Math.Min(roller.y, ypos >> 16) - 14;
int maxx = Math.Max(roller.x, xpos >> 16) + 14;
int maxy = Math.Max(roller.y, ypos >> 16) + 14;
roller.dangerArea = Rectangle.FromLTRB(minx, miny, maxx + 1, maxy + 1);
roller.endTime = (ushort)t;
period++;
int remainder = t % period;
if (remainder != 0)
{
t += period - remainder;
}
roller.period = (ushort)t;
List <Roller> res = new List <Roller>();
for (; t > 0; t -= period)
{
res.Add(roller);
roller = (Roller)roller.MemberwiseClone();
roller.startTime += (ushort)period;
//roller.endTime += (ushort)period;
}
return(res);
}
