diff options
| author | Jérémy Zurcher <jeremy@asynk.ch> | 2020-06-02 16:49:22 +0200 |
|---|---|---|
| committer | Jérémy Zurcher <jeremy@asynk.ch> | 2020-06-02 16:49:22 +0200 |
| commit | cc2414cf7c4d94160addbc46399e3586d6eb0845 (patch) | |
| tree | da03e1c03bcd696b66987b5440573373e8d2153b | |
| parent | 783bfb7a8b085f4373cdcc28fbbac53063ccf68d (diff) | |
| download | gdx-boardgame-cc2414cf7c4d94160addbc46399e3586d6eb0845.zip gdx-boardgame-cc2414cf7c4d94160addbc46399e3586d6eb0845.tar.gz | |
HexBoard : add comments to lineOfSight
| -rw-r--r-- | core/src/ch/asynk/gdx/boardgame/boards/HexBoard.java | 37 |
1 files changed, 23 insertions, 14 deletions
diff --git a/core/src/ch/asynk/gdx/boardgame/boards/HexBoard.java b/core/src/ch/asynk/gdx/boardgame/boards/HexBoard.java index 7c3febb..4afe951 100644 --- a/core/src/ch/asynk/gdx/boardgame/boards/HexBoard.java +++ b/core/src/ch/asynk/gdx/boardgame/boards/HexBoard.java @@ -262,6 +262,8 @@ public class HexBoard implements Board } } + // http://zvold.blogspot.com/2010/01/bresenhams-line-drawing-algorithm-on_26.html + // http://zvold.blogspot.com/2010/02/line-of-sight-on-hexagonal-grid.html @Override public boolean lineOfSight(int x0, int y0, int x1, int y1, Collection<Tile> tiles) { tiles.clear(); @@ -272,8 +274,8 @@ public class HexBoard implements Board int dy = y1 - y0; int dx = ox1 - ox0; - // same sign - boolean sig = !(((dx < 0) && (dy >= 0)) || ((dx >= 0) && (dy < 0))); + // quadrant I && III + boolean q13 = (((dx >= 0) && (dy >= 0)) || ((dx < 0) && (dy < 0))); // is positive int xs = 1; @@ -301,7 +303,7 @@ public class HexBoard implements Board if (dx == dy3) return diagonalLineOfSight(x0, y0, x1, y1, tiles); - // angle is smaller than diagonal + // angle is less than 45° boolean flat = (dx > dy3); int x = x0; @@ -312,25 +314,31 @@ public class HexBoard implements Board Tile to = getTile(x1, y1); tiles.add(from); boolean losBlocked = false; + while ((x != x1) || (y != y1)) { if (e > 0) { + // quadrant I : up left e -= (dy3 + dx3); y += ys; - if (!sig) + if (!q13) { x -= xs; + } } else { e += dy3; if ((e > -dx) || (!flat && (e == -dx))) { + // quadrant I : up right e -= dx3; y += ys; - if (sig) + if (q13) x += xs; } else if (e < -dx3) { + // quadrant I : down right e += dx3; y -= ys; - if (!sig) + if (!q13) x += xs; } else { + // quadrant I : right e += dy3; x += xs; } @@ -358,7 +366,7 @@ public class HexBoard implements Board while ((x != x1) || (y != y1)) { boolean blocked = losBlocked; - y += d; + y += d; // up left Tile t = getTile(x, y); if (t.isOnMap()) { tiles.add(t); @@ -366,7 +374,7 @@ public class HexBoard implements Board blocked = (blocked || t.blockLos(from, to)); } - x += d; + x += d; // up right t = getTile(x, y); if (t.isOnMap()) { tiles.add(t); @@ -374,7 +382,7 @@ public class HexBoard implements Board blocked = (blocked && t.blockLos(from, to)); } - y += d; + y += d; // vertical t = getTile(x, y); if (t.isOnMap()) { tiles.add(t); @@ -390,7 +398,8 @@ public class HexBoard implements Board { int dy = ( (y1 > y0) ? 1 : -1); int dx = ( (x1 > x0) ? 1 : -1); - boolean sig = !(((dx < 0) && (dy >= 0)) || ((dx >= 0) && (dy < 0))); + // quadrant I && III + boolean q13 = (((dx >= 0) && (dy >= 0)) || ((dx < 0) && (dy < 0))); int x = x0; int y = y0; @@ -402,7 +411,7 @@ public class HexBoard implements Board while ((x != x1) || (y != y1)) { boolean blocked = losBlocked; - x += dx; + x += dx; // right Tile t = getTile(x, y); if (t.isOnMap()) { tiles.add(t); @@ -410,8 +419,8 @@ public class HexBoard implements Board blocked = (blocked || t.blockLos(from, to)); } - y += dy; - if (!sig) + y += dy; // up right + if (!q13) x -= dx; t = getTile(x, y); if (t.isOnMap()) { @@ -420,7 +429,7 @@ public class HexBoard implements Board blocked = (blocked && t.blockLos(from, to)); } - x += dx; + x += dx; // diagonal t = getTile(x, y); if (t.isOnMap()) { tiles.add(t); |