From d55361ae3ab117da99d953aa76117cb6630ddf05 Mon Sep 17 00:00:00 2001
From: gered <gered@blarg.ca>
Date: Wed, 3 Jul 2013 18:31:17 -0400
Subject: [PATCH] add AutoGridTextureAtlas

---
 .../gdx/graphics/AutoGridTextureAtlas.java    | 57 +++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 src/com/blarg/gdx/graphics/AutoGridTextureAtlas.java

diff --git a/src/com/blarg/gdx/graphics/AutoGridTextureAtlas.java b/src/com/blarg/gdx/graphics/AutoGridTextureAtlas.java
new file mode 100644
index 0000000..1dec1eb
--- /dev/null
+++ b/src/com/blarg/gdx/graphics/AutoGridTextureAtlas.java
@@ -0,0 +1,57 @@
+package com.blarg.gdx.graphics;
+
+import com.badlogic.gdx.graphics.Texture;
+import com.badlogic.gdx.graphics.g2d.TextureRegion;
+
+public class AutoGridTextureAtlas extends TextureAtlas {
+	public final int tileWidth;
+	public final int tileHeight;
+	public final int tileBorder;
+
+	public AutoGridTextureAtlas(Texture texture, int tileWidth, int tileHeight, int tileBorder) {
+		this(texture, tileWidth, tileHeight, tileBorder, TEXCOORD_EDGE_BLEED_OFFSET);
+	}
+
+	public AutoGridTextureAtlas(Texture texture, int tileWidth, int tileHeight, int tileBorder, float edgeCoordOffset) {
+		super(texture, edgeCoordOffset);
+		this.tileWidth = tileWidth;
+		this.tileHeight = tileHeight;
+		this.tileBorder = tileBorder;
+
+		generateGrid();
+	}
+
+	private void generateGrid() {
+		int actualTileWidth = tileWidth + tileBorder;
+		int actualTileHeight = tileHeight + tileBorder;
+
+		int tilesX = (texture.getWidth() - tileBorder) / (tileWidth + tileBorder);
+		int tilesY = (texture.getHeight() - tileBorder) / (tileHeight + tileBorder);
+
+		for (int y = 0; y < tilesY; ++y)
+		{
+			for (int x = 0; x < tilesX; ++x)
+			{
+				// pixel location/dimensions
+				int left = tileBorder + x * actualTileWidth;
+				int top = tileBorder + y * actualTileHeight;
+				int right = left + actualTileWidth - tileBorder;
+				int bottom = top + actualTileHeight - tileBorder;
+
+				// texture coordinates
+				// HACK: subtract edgeCoordOffset from the bottom right edges to
+				//       get around floating point rounding errors (adjacent tiles will
+				//       slightly bleed in otherwise)
+				float u = (left - tileBorder + edgeCoordOffset) / (float)texture.getWidth();
+				float v = (top - tileBorder + edgeCoordOffset) / (float)texture.getHeight();
+				float u2 = ((float)right + tileBorder - edgeCoordOffset) / (float)texture.getWidth();
+				float v2 = ((float)bottom + tileBorder - edgeCoordOffset) / (float)texture.getHeight();
+
+				TextureRegion tile = new TextureRegion();
+				tile.setTexture(texture);
+				tile.setRegion(u, v, u2, v2);
+				tiles.add(tile);
+			}
+		}
+	}
+}