diff options
| -rw-r--r-- | core/src/ch/asynk/tankontank/engine/SearchBoard.java | 106 |
1 files changed, 105 insertions, 1 deletions
diff --git a/core/src/ch/asynk/tankontank/engine/SearchBoard.java b/core/src/ch/asynk/tankontank/engine/SearchBoard.java index 6131a69..bd1ce2b 100644 --- a/core/src/ch/asynk/tankontank/engine/SearchBoard.java +++ b/core/src/ch/asynk/tankontank/engine/SearchBoard.java @@ -283,5 +283,109 @@ public class SearchBoard return result; } -} + public List<Node> lineOfSight(int x0, int y0, int x1, int y1) + { + return lineOfSight(x0, y0, x1, y1, true); + } + + public List<Node> lineOfSight(int x0, int y0, int x1, int y1, boolean check) + { + result.clear(); + + // orthogonal axis + int ox0 = x0 - ((y0 +1) / 2); + int ox1 = x1 - ((y1 +1) / 2); + + int dy = y1 - y0; + int dx = ox1 - ox0; + + int xs = 1; + int ys = 1; + if (dx < 0) xs = -1; + if (dy < 0) ys = -1; + boolean sig = !(((dx < 0) && (dy >= 0)) || ((dx >= 0) && (dy < 0))); + + dy = Math.abs(dy); + dx = Math.abs(2 * dx); + if ((dy % 2) == 1) { + if ((y0 % 2) == 0) dx += xs; + else { + dx -= xs; + Math.abs(dx); + } + } + if (dx == 0) + return verticalLineOfSight(x0, y0, x1, y1, check); + + int dx3 = 3 * dx; + int dy3 = 3 * dy; + + int x = x0; + int y = y0; + int e = -2 * dx; + + boolean vert = (dx == 0); + boolean flat = (dx > (3 * dy)); + boolean diag = (dx == (3 * dy)); + + int step = 0; + result.add(getNode(x, y)); + while((x != x1) || (y != y1)) { + if (e > 0) { + e -= (dy3 + dx3); + y += ys; + if (!sig) + x -= xs; + } else { + e += dy3; + if ((e > -dx) || (!flat && (e == -dx))) { + e -= dx3; + y += ys; + if (sig) + x += xs; + } else if ((e < -dx3) || (diag && (e == -dx3))) { + e += dx3; + y -= ys; + if (!sig) + x += xs; + } else { + e += dy3; + x += xs; + } + } + result.add(getNode(x, y)); + step += 1; + if (step > 20) { + return result; + } + } + + return result; + } + + private List<Node> verticalLineOfSight(int x0, int y0, int x1, int y1, boolean check) + { + int d = ( (y1 > y0) ? 1 : -1); + int x = x0; + int y = y0; + + Tile t = null; + result.add(getNode(x, y)); + while((x != x1) || (y != y1)) { + y += d; + t = board.getTile(x, y); + if (!t.isOffMap()) result.add(getNode(x, y)); + + x += d; + t = board.getTile(x, y); + if (!t.isOffMap()) result.add(getNode(x, y)); + + y += d; + t = board.getTile(x, y); + if (!t.isOffMap()) result.add(getNode(x, y)); + } + + return result; + } +} |